Barley Value Chain
Description
Barley is an annual cereal of the grass family. It matures in a relatively short period of time and is therefore adapted to growing in a wide variety of environments. Barley species make up the genus Hordeum, which belongs to the family Poaceae, in the order Cyperales, class Liliopsida. Some of the wild species are weed like and have only a slight similarity in appearance to cultivated barley.
- vulgare,known as common barley, is cultivated in two- and six-rowed varieties, the small barley flowers (florets) occurring in groups of three on alternate sides of the plant’s head (spike). In six-rowed barley all of the florets are fertile and produce seeds, thus creating six rows of seeds along the spike. In the two-rowed plants (formerly classified as a separate species, H. distichon), the outer florets of each group of three are sterile, leaving only one row of seeds on each side of the spike.
Each barley seed is enclosed in a strong outer covering (hull), which remains intact even during threshing. The naked barley seed within this hull is similar in shape to a kernel of wheat. The kernels of important varieties of barley are white or blue, but black-, red-, and purple-seeded varieties also exist. https://hubpages.com/food/Barley-Types-and-Description
Land Preparation
Barley is adapted to a wide range of soils such as less fertile, fertile, sandy or soils. But to get a good crop stand and better crop yield soil preparation is an important step. To prepare soil for barley, plough field with a deep plough it twice with sub-soiler or chisel and then level the field by planking. To remove the stubbles of the previous Kharif crops such as rice or maize, use of rotavator or disc harrow is beneficial. Daab method of flooding the field for weed eradication followed by double ploughing and double planking is also good for preparation of seedbed. http://pakagrifarming.blogspot.com.ng/2013/02/production-technology-of-barley-hordeum.html
Climatic and Soil Requirement
Climatic requirements It requires a shorter growing period and needs an average temperature of 15 to 17 °C during flowering. The annual temperatures required range from 5 to 27 °C (low temperatures and high temperatures du ring ripening). It tolerates high temperatures.
Rainfall
The seasonal water requirement for barley depends on the variety, targeted yield and crop management. Barley is a drought resistant crop and requires 390 to 430 mm of rainfall for optimum yield. Maximum water use will occur for 21 to 28 days.
Soil requirements
Barley can be grown on a wide range of soil types; ranging from heavy clays to light or sandy loam soils. It grows well on fertile, deep loam soils with a pH of 6 to 7, 5. Soils with a pH lower than 6 may induce aluminium toxicity, leading to poor growth. Barley is more sensitive to very wet conditions but more tolerant to alkaline soil than the other small grains. http://www.daff.gov.za/Daffweb3/Portals/0/Brochures%20and%20Production%20guidelines/Brochure%20Barley.pdf
Variety
Barley Varieties and their Characteristics
Traditionally grown barley varieties are tall and weak stemmed and generally lodge even under relatively low soil fertility conditions. Therefore, researches on varietal improvement have restructured the plant type to take full advantage of higher level of soil fertility and irrigation. Some of the newly evolved varieties and their characteristics are described below.
- Ratna: Ratna variety was developed at IARI, New Delhi and released for rainfed areas of eastern Uttar Pradesh, Bihar and West Bengal. It is highly tolerant to saline, alkaline soil conditions. It yields about 150 q/ha of green fodder after 65 days of sowing and regeneration crop yielding 20 quintals of seed per hectare. If the green fodder is not taken, it yields about 25-30 quintals grain per hectare. It matures within 125-130 days and gives a fairly good yield even under unfavourable environmental conditions. Plants have good tillering ability. Ear size is 9.0-9.5cm.
- Azad (K.125): Azad variety has been developed at C.S.A. University of Agriculture and Technology, Kanpur. It is suitable for cultivation in areas of eastern Uttar Pradesh, Bihar and West Bengal. It is highly responsive to improved management practices. It has a fair degree of resistance to yellow rust disease. It does well under irrigated conditions. It is good for dual purpose like fodder and grain. It yields about 150 quintals of green fodder per hectare after 65 days of sowing and regenerates to produce a yield of 20 quintals per hectare of grain. It matures in 115-120 days. It has yield potential, of 35-38 quintals of grain per hectare under irrigated conditions.
- Vijaya: Vijaya variety has been developed at C.S.A University of Agriculture and Technology, Kanpur and released for rainfed areas of western Uttar Pradesh, I Delhi and Madhya Pradesh. It matures in 120-125 days. Plants of this variety are shorter in height as compared to other varieties. It does well in rainfed areas of Haryana and Punjab also. It has yield potential of 30-35 quintals of grains per hectare.
- Amber: This variety has also been developed at C.S.A. University of Agriculture and Technology, Kanpur. It matures in 130-133 days. Plants are 100-125cm in height. Ear size is 8.5-9.5 cm. It is suitable for growing in rainfed areas of eastern Uttar Pradesh. It is good for the production of malt for brewing. It has yield potential of 25-30 quintals of grains per hectare.
- RS-6: The variety RS-6 was developed in Rajasthan. It is suitable for cultivation under both rainfed as well as irrigated conditions. It has been recommended for central and eastern Rajasthan. It matures in 130-135 days. It has yield potential of 35 to 40 quintals of grain per hectare. It is very good for production of malt for brewing.
- Jyoti: Jyoti is a Six-row hulled variety. It has been developed at the C.S.A. University of Agriculture and Technology, Kanpur. It is suitable for growing in irrigated areas of Haryana, Punjab, Uttar Pradesh. Delhi, north-western Rajasthan, Bihar and West Bengal. Plant height is short. It has yield potential of about 35-40 quintals of grains per hectare. It matures in 120-125 days, under irrigated conditions, yielding 20-25 quintals of grains per hectare.
- Clipper: Clipper has been introduced from Australia. It is especially suitable for malt production and brewing. It matures in about 135-140 days. It is susceptible to yellow rust. It has yield potential of 28-30 quintals of grains per hectare under good management. However, this variety could not become popular among the farmers.
- PL-56: PL-56 is a six-row variety with broad and relatively upright leaves and a colour less leaf sheath. It has compact ears with well spread, barbed awns. It is moderately resistant to yellow rust. It is recommended for cultivation under rainfed conditions of Punjab. It has yield potential of30 quintals of grains per hectare.
- Ranjit (DL- 70): Ranjit variety of barley grows 75-85cm tall and is shorter by 15-20 cm than other varieties. It is six-row and heavy tillering variety, recommended for commercial cultivation in Punjab only. It is suitable for growing under irrigated conditions. It has yield potential of 30-35 quintals of grains per hectare. Due to its early maturity, it fits well in multiple crop rotations for late, I sowing after the harvest of crops such as potato, cotton or paddy.
- Karan-201, 231 and 264: Varieties Karan 201, 231 and 264 have been evolved under the All India Coordinated Barley Improvement Project. These are high yielding varieties and good for chappati making. All of them are huskless varieties. These varieties fit in well in the multiple and relay cropping systems. These can be grown in problem soils too, like dry lands, alkaline and saline soils, etc. They can also be grown on lands lying fallow after a paddy crop has been taken. These are suitable for cultivation in the eastern and Bundelkhand region of Madhya Pradesh, Rajasthan and Gurgaon and Mohindergarh district of Haryana. The average yield of Karan 201, 231 and 264 are 38, 42.5 and 46 quintals per hectare, respectively.
- C- l64: Variety C-164 is a tall, six-row variety with compact ears and long awns. Its grain is bold, bright and amber. It is resistant to yellow rust. It has stiff straw and is, therefore, more suitable for cultivation under irrigated conditions. It has yield potential of 30-32 quintals of grain per hectare.
- Kailash: Variety Kailash is a six-row hulled variety suitable for growing in rainfed areas of medium to low elevation of Himachal Pradesh hills. It matures in 145-150 days. It is resistant to yellow rust. It has yield potential of about 40 quintals of grain per hectare.
- Dolma:The variety Dolma is suitable for growing in rainfed areas of medium to high elevation of Himachal Pradesh and Uttar Pradesh hills. It matures in about 140-150 days. It is fairly resistant to yellow rust. It has yield potential of 35-40 quintals per hectare.
- Himani: Himani variety was developed at Simla. It is suitable for growing in the medium to lower hill-valley of Uttar Pradesh and Himachal Pradesh. It matures about one week earlier than Kailash. It has yield potential of 32-36 quintals of grains per hectare.
- LSB-2: LSB is a six-row naked type barley variety suitable for growing at higher altitude of Himachal Pradesh and Uttar Pradesh hills. It matures in 145-150 days. It has yield potential of 25-30 quintals of grain per hectare.
- RDB-1: RDB-1 has been developed by mutation. It is suitable for growing under irrigated conditions in Rajasthan. It is susceptible to yellow rust and is suitable for rust free areas of Rajasthan. It has yield potential of 30-35 quintals of grain per hectare.
- BG-25: This variety has been developed at Haryana Agricultural University, Hissar. It is suitable for normal sowing conditions in Haryana. It is resistant to yellow rust. It matures in about 120-130 days. It has yield potential of about 30 quintals of grain per hectare.
- BG-108: This variety has been developed at Haryana Agricultural University, Hissar for commercial cultivation under late sown conditions. It takes about 120-125 days to mature. It is fairly resistant to yellow rust. It has yield potential of 20-25 quintals per hectare under late sown conditions.
- Kedar: This high yielding variety of barley has been evolved by Indian Agricultural Research Institute, New Delhi. It is suitable for late sown conditions. Kedar is a dwarf variety with profuse tillering and resistant against yellow rust and insects.
- Neelam: This variety yields up to 50 quintals per hectare. Its grains are hulled and amber in colour. This variety has been evolved by Indian Agricultural Research Institute, New Delhi, and is recommended for cultivation in both irrigated and rain fed conditions of Punjab, Haryana, Uttar Pradesh, and Bihar. This variety has higher contents of protein and lysine.
http://agropedia.iitk.ac.in/content/barley-varieties-and-their-characteristics
Planting time
Barley is very versatile in its planting time as it has a slightly lower frost tolerance (1°C) than wheat and can be planted earlier in the season. It is also often a better option than wheat for late planting, especially if feed grain prices are good. Preferred planting times are from late April to June but this will vary for each region depending on frosts and seasonal effects. In the cooler areas of southern Queensland planting can occur into July.
Early planting will generally produce higher yields, larger grain size and lower protein levels making it more likely to achieve malt quality. However, early crops are more likely to have exposure to frost and growers should assess the frost risk for their area prior to sowing. Late plantings will often mature in hot dry weather which can reduce grain size, yield and malting quality.
Planting at the right time for your area:
Sowing at the right time is critical for optimising grain yield and can also influence grain quality.
Early planting may increase the frost risk, but has the highest yield potential and is more likely to make malt quality.
Planting too early can result in the crop running quickly to head if a warm late autumn or warm early winter occurs.
Later maturing and shorter stature varieties are preferred for early planting to avoid tall lush early growth.
At flowering barley can tolerate 1°C lower frost than wheat.
A frost of -4°C at head height during flowering can cause between 5-30% yield loss.
A frost of -5°C or lower at head height can cause 100% yield loss.
A strongly negative April/May Southern Oscillation Index (SOI) is a good indicator of late frosts.
Hot dry temperatures during spring can reduce grain fill period and affect yield and grain size.
Later planting and later flowering generally results in declining yield potential due to higher temperatures and moisture stress during flowering.
Plant populations
While barley can produce a large number of tillers, best yields will be achieved with an established plant stand of 800,000 to 1.2 million plants/ha (80-120 plants/square metre). While barley can tolerate quite high plant populations without significant yield reductions, if plant populations fall below 80 plants per square metre, yield can be reduced. Lower plant populations can also encourage excess or late tillering resulting in a less even crop and delayed harvest. Late tillers often have smaller seed which also affects the quality of the crop.
Planting rate
Planting rate is the kilograms of seed needed to plant in order to establish the target plant population. To determine planting rate you need to know the target plant population, the number of seeds per kg, the germination percentage of the seed and the likely field establishment.
The number of seed per kg will vary depending on variety and the season in which the seed was produced. This varies from season to season and to calculate this figure, count the number of seeds in a 20 g sample and multiply by 50. Newer varieties tend to have larger seed and it is important to take note of this in determining planting rate.
Field establishment
Field establishment refers to the number of viable seeds that produce established plants after planting. This can be affected by factors such as seedbed moisture, disease, soil insects, depth of planting, and the germination percentage of the seed. An establishment figure of 70% means that for every 10 seeds planted only seven will emerge to produce a viable plant.
It is important to check establishment after planting in order to evaluate the effectiveness of the planting technique and make adjustments if necessary.
A guide to likely field establishment, when good quality seed with a laboratory germination of 90% or better is planted at a depth of 5-7 cm and emerges without the assistance of post-planting rains, is set out below.
| Likely field establishment (%) | ||
| Soil type | No press wheels % | Press wheels % |
| Heavy clay | 45 | 60 |
| Brigalow clay | 55 | 70 |
| Red earth | 70 | 80 |
| Approximate seeding rates (kg/ha) assuming 90% germination from field establishments (%) | ||||
| Desired population (plants/ha) | 60 | 70 | 80 | 90 |
| 700,000 | 52 | 45 | 39 | 34 |
| 900,000 | 67 | 57 | 46 | 44 |
| 1,000,000 | 74 | 63 | 56 | 49 |
Use higher sowing rates for grazing crops and very early or late crops.
Planting rates can be calculated for any variety or situation by using the following formula:
Planting rate (kg/ha) = Desired population (pl/ha) ÷ (Seeds per kg x germination x establishment)
Note: germination and establishment figures are decimal e.g. 80%=0.8, 90%=0.9, etc.
Example:
Desired plant population of 900,000 pl/ha
Germination = 95%
Expected establishment = 85%
No of seeds/kg = 25,000
Planting rate (kg/ha) = 900,000 (pl/ha) ÷ (25,000 x 0.95 x 0.85)
Planting rate = 44.6 kg/ha
Row spacing
No yield reductions have been recorded for row spacing up to 36 cm. Rows wider than 36 cm have caused minor yield reductions, particularly in good seasons. Wider rows are more predisposed to lodging and will reduce the level of weed smothering due to canopy ground cover.
Planting depth
The ideal depth for planting barley is 50-75 mm. Plant emergence may be reduced if seed is sown deeper than 75 mm. Plant seed into moisture at the minimum depth possible. For successful establishment, the root must continue to grow into wet soil. Press wheels can improve the contact between seed and wet soil and reduce the rate of drying of soil above the seed. Particular care should be taken with planting depth if using seed with fungicidal dressing which may shorten the coleoptile length and make establishment from depth more difficult. Check the label before use.
The erratic nature of planting rains has resulted in some growers taking opportunities to sow barley at greater depths than the recommended 50-70mm. As a very vigorous seedling this has generally been successful for barley if good planting techniques are applied. In trials barley has emerged from as far as 15cm. A few tips to take into account include:
avoid the shorter coleoptile (dwarf) varieties
avoid seed dressings which contain triadimenol as these can shorten the coleoptile and make emerging from depth more difficult
try to minimise the amount of soil which is placed back over the top of the planting furrow.
ensure that the seed planted has good germination and vigour.
Nutrition Requirement
Nitrogen (N)
Management of nitrogen availability is vital to achieve optimal yields and quality in your barley crop. The level of nitrogen and plant available water will impact strongly on yield and protein having potentially a major impact on crop return. Unlike wheat where premiums are available for high protein barley premiums for malting require moderate proteins of 9-12%. If you target around 12% protein this will also be maximising yield potential for barley.
A large percentage of Queensland’s barley crop is classified as feed with protein levels above 12%. Older cultivation or double crop situations with lower soil N supplies can produce malt-grade barley especially in a good season, however, skill is required to balance the requirement for nitrogen to maximise yield without over fertilising and increasing the protein level.
A rule of thumb used by some is to grow malting barley, 0.4 kg of nitrogen is required for every mm of available soil moisture. Thus if there is 150 mm of available soil moisture, this will require 60 kg of nitrogen to produce a barley crop with protein between 8.5-12%. In high yielding years, grain protein can be reduced through nitrogen dilution as grain yield increases.
Nitrogen calculations for barley
Determining soil nitrogen status
Before a fertiliser program can be decided on it is important to gain an estimate of the existing soil nutrient status. Continuously low grain protein levels are indicative of a lower soil nitrogen supply. When barley protein levels are below 11.5% dry or below 10-11% (at 12.5% moisture) grain yield losses are likely.
Monitoring crop yields and protein over time can give a good indication of the nitrogen status of a paddock.
| Using grain protein of preceding barley and wheat crops as an indicator of paddock nitrogen status | ||
| Barley protein (dry basis) % |
Wheat protein (11% moisture) % |
Comments |
| Less than 8.5 | Less than 10 | Acutely nitrogen deficient. Potential yield loss may be in excess of 30%. Applied N should increase yield significantly. Grain protein would be increased only if a large amount of N was applied. |
| 8.5-11 | 10-11.5 | Moderately to slightly nitrogen deficient. At least 15% yield loss is likely because of low soil N. Yield would probably be increased by applying N if there were no other limiting factors (e.g. soil moisture). |
| 11-12 | 11.5-12.5 | Satisfactory nitrogen status for optimum yield. Additional N would probably not increase yield but would be likely to increase grain protein. |
| Greater than 12 | Greater than 12.5 | Nitrogen not deficient. Yield was most likely limited by water deficit. Additional N would not increase yield but would probably increase grain protein. If high protein and low yield occur, even in years of good rain, phosphorus may be deficient. |
| Indicative N fertiliser required (kg/ha) to produce the target yield (t/ha) of barley with 11.5% grain protein dry. | |||||
| Target yield (t/ha) at 11.5% protein (dry) | 2 | 3 | 4 | 5 | |
| Total N required (kg/ha) | 75 | 110 | 145 | 180 | |
| Cropping history | Estimated available soil N (kg/ha)* | Balance of N required as fertiliser (kg/ha) | |||
| Double-cropped from sorghum | 30 | 45 | 80 | 117 | 152 |
| Fallowed from winter cereal | 55 | 20 | 55 | 92 | 127 |
| Fallow from chickpeas (yielding 0.5-1.0 t/ha) | 65 | 10 | 45 | 82 | 117 |
| Fallow from chickpeas (yielding 1.0-1.5 t/ha) | 75 | 0 | 35 | 72 | 105 |
It is assumed that 30 kg N/ha will be released from the soil as the crop is growing and the difference in soil N up to the value indicated was present at sowing.
Calculating nitrogen requirement
Another way to calculate nitrogen requirement is by measuring existing soil nitrogen and estimating a target yield and protein.
Calculate available soil water e.g. using How Wet, stored soil moisture and estimated in-crop rainfall.
Estimate target grain yield and protein %. – based on available moisture (e.g. 3.5 t/ha @ 10.1 % protein). Crop simulations such as Whopper Cropper can generate yield probabilities for a range of starting soil moisture and sowing dates. Ideal malting barley grain protein is about 11.5% dry (optimum yield) or 10.1 % wet @ 12% grain moisture. Target for feed barley grain protein is about 12% dry (max yield) or 10.5% wet at 12.5% grain moisture.
Calculate how much nitrogen will be harvested in the grain. Grain N (kg/ha) = Yield (t/ha) x protein % x 1.6 (e.g. for the above target yield and protein 3.5 x 10.1 x 1.6 = 57 kg N/ha).
Calculate N required to grow the crop. Barley requires roughly twice the amount of N in the grain. N required for crop (kg/ha) = Grain N x 2 e.g. (3.5 x 10.1 x 1.6) x 2 = 113 kg N/ha.
# Estimate or measure the soil nitrogen e.g. use soil tests (including the soil profile to 90 or 120 cm), or previous crop yields and proteins. Include mineralisation (generally about 30kg N/ha).
Calculate the extra N required. Extra N required = N required to grow crop – soil N. For example, if there is 10 units of N in the soil and an estimated 30 units to be mineralised and a total of 113 units of N to grow your crop of 3.5 mt/ha @ 10.1 % protein.
The equation will be 113 (total N required) – 40 (total available or to be mineralised) = 73 kg/ha of N. If using a product such as urea which is 46% N you will need 158 kg/ha of urea. (73/0.46).
Phosphorus (P)
Phosphorus deficiency is widespread throughout the Darling Downs region with over 60% of all agricultural soils being responsive to phosphorus fertilisers. Low phosphorus levels in a high nitrogen situation can result in delayed flowering which affects the yield potential and grain filling time of the crop. For optimum performance it is recommended to use a starter fertiliser with phosphorus unless levels are very high.
| Phosphorus recommendations | |
| Bicarb P (mg/kg) | Recommendations (P/ha) |
| 0-10 | Response most likely. Apply 8 kg P |
| 11-15 | Response likely. Apply 6 kg P |
| 16-20 | Response possible. Test strip of 6 kg P |
| above 20 | Response unlikely |
The combination of the fungus and the crop root is known as Vesicular-Arbuscular-Mycorrhiza (VAM). Long fallowing can increase the response of deficient soils to phosphorus due to the absence of VAM. This should not be a major concern for barley as it has a low requirement for VAM.
Other Nutrients
Zinc (Zn)
Deficiency does occur in some of the alkaline brigalow soils and some of the heavy, alkaline flooded clay soils along the river systems, particularly following a long fallow. As zinc plays an important role in the efficient uptake of nitrogen for protein its significance should not be ignored and any suspected deficiencies should be addressed. Zinc deficiency can be corrected by applying a zinc fertiliser with the seed at planting or incorporating zinc sulfate monohydrate into the soil two to three months prior to planting.
Copper (Cu)
Deficiency has occurred in a band from Wandoan through Miles, Tara, and Moonie to Goondiwindi. The area affected, however, is patchy and small.
Sulfur (S)
Can be a problem in areas with a long history of cultivation. If sulphur deficiency is suspected, use a test strip to indicate potential response. It is more likely to occur after short fallow or double-crop situations, where soil sulphur levels have been depleted by the previous crop.
Irrigation of barley
Barley has a high water use efficiency rating. The plant can extract moisture from below 80 cm and given a good starting moisture profile, high yielding crops can be grown on limited irrigation. Yields of 7.3 mt/ha and higher have been recorded. Growers should target yields of 5-6 mt/ha and proteins of 10.1% (dry) or 11.5% wet basis to maximise yield and quality. Requirements for water will depend on winter rainfall and irrigation systems but one of the crucial times to apply water for achieving malt quality is grain fill. Adequate moisture during tillering and early jointing is important for maximising potential yield.
It is a good rotation crop to breaking disease and weed cycles, and providing high stubble levels. https://www.daf.qld.gov.au/plants/field-crops-and-pastures/broadacre-field-crops/barley/planting-nutrition-harvesting
Pest and Diseases Management
Diseases occur when a susceptible host is exposed to a virulent pathogen under favourable environmental conditions.
Control is best achieved by knowledge of the pathogens involved and manipulation of the interacting factors. Little can be done to modify the environment but growers can minimise the risk of diseases by sowing resistant varieties and adopting practices to reduce inoculum.
Resistant varieties provide the easiest and most effective option, yet few varieties possess adequate resistance to all major diseases. Alternative strategies are therefore required to reduce risk.
Rotate barley crops with non-hosts such as wheat (to control foliar pathogens), legumes or summer crops; avoid sowing barley on barley and maintain clean fallows. Sowing out of season favours disease development and can build up inoculum early in the season.
The main foliar diseases of barley are leaf spots, rusts and powdery mildew. Leaf spots and powdery mildew occur over season on crop residues while rusts (and to a lesser extent, powdery mildew) require living plants to carry them from one season to the next.
Growers should assess the disease risk of individual paddocks before sowing. Consider the recent history of a paddock, the incidence of diseases in recent barley crops and the amount of infected stubble in the target and neighbouring paddocks. Infected stubble can usually be recognised by the presence of small black ‘pimples’ on the straw.
Head and root diseases
Crown rot (Fusarium psuedograminearum)
Common in winter cereals. It is soil-borne and can be carried over from one season to the next on barley and wheat stubble. A barley variety with the same rating as a wheat variety will not suffer the same level of yield loss. However, yield losses as high as 28% have been recorded. Rotation with chickpeas or summer crops is currently the best method of controlling crown rot as there are no varieties which possess adequate field resistance.
Covered smut (Ustilago hordei)
A photo of covered smut in heads of barley
Recognised by the appearance of masses of spores (fungal seeds) enclosed in a semi-persistent membrane that covers the smutted spikelets. This is in contrast to loose smut of barley where there is no membrane and the head is a ragged mass of spores. Covered smut survives as teliospores (resting spores) on seed or in infested soil.
Spores geminate when the soil temperature range is 14-25ºC and soil moisture is low. Infection occurs as the seedlings emerge from the sprouting seed. The fungus enters the young seedling and grows within the growing point of the developing barley plant.
The greater the amount of infection on this tissue, the greater the number of tillers per plant infected.
In smut-infected plants, a smutted head emerges rather than a flowering barley head. The membrane covering the smutted tissues keeps the smut spores (teliospores) from being dispersed until harvest.
At harvest thin membranes that cover the sori are ruptured and the spores are released and mix with healthy seed or fall to the ground. When the membrane ruptures prior to harvest, spores are blown to healthy seed. Teliospores contaminate the exterior portion of the seed, especially the crevice.
Spores which land between the kernel and the hull germinate when adequate moisture is present. The mycelium arising from these spores goes dormant after it becomes established. Spores on the seed and dormant mycelium associated with hulls are responsible for most of the infection in the subsequent growing season.
If growers have any concerns about infection of their seed they should look at accessing seed from a clean source. The cost of treating seed is minimal in comparison to losing production or not being able to market the grain. As the disease can be soil borne as well as seed borne it is recommended that planting seed be treated every year regardless of cleanliness of the seed source.
Seed obtained through reputable seed companies should be treated, however farmer kept or farmer traded seed may not be treated and growers need to be wary.
Seed treatments are available for control of:
- covered and loose smuts
- seed borne net blotch (net form)
- seed borne spot blotch
- powdery mildew (up to eight weeks protection).
Common root rot (Cochliobolus sativus)
Also soil-borne. It is widespread in barley crops and may cause yield losses of up to 15%. As there are no varieties resistant to this disease, rotation with summer crops or winter legumes is the best method of control.
See the Barley variety characteristics table for information on variety resistance to diseases.
Black point in barley
Black point is a dark discolouration at the germ end of otherwise healthy barley grain. Yellowing of the germ end of the grain is probably also a variation of black point discolouration. The discolouration occurs in the glume tissue (palea and lemma) which remains adhered to the outer seed coat.
The conditions that cause high levels of black point in wheat often do not cause any discolouration in barley. The precise nature and timing of the environmental stresses that induce black point symptoms are not fully understood, however, yield, humidity and temperature are likely to be involved.
Black point causes a slight reduction in the rate of germination but without a significant effect on the malting process. However, in combination with shrivelling, field mould or disease, grain health may be affected and germination rates reduced.
Root-lesion Nematode (Pratylenchus thornei)
Barley is tolerant to root-lesion nematode infection and is therefore a good winter cropping option in infested areas. Although barley is more tolerant than many wheat varieties and most varieties are resistant to very resistant, nematode numbers in the soil may still increase under barley cropping. Rotations using resistant crops are encouraged.
Foliar diseases
The following table outlines the common foliar diseases and the basic information on survival dispersal infection times and control options.
| Barley foliar disease reference table | ||||||
| Disease | Survival mode | Optimal conditions | Dispersal | Growth stage when infected (Zadoks) | Pot. yield loss (%) | Control options |
| Leaf rust | Living barley plants | 15-22ºC; free moisture(dews) |
Airborne | 20-90 tillering to maturity |
30+ | Prevent green bridge Resistant varieties Fungicides Timely sowing |
| Stem rust | Living wheat, barley, rye, or rough wheat grass | 20-30ºC free moisture(dews) |
Airborne | >40 booting to maturity |
50+ | Prevent green bridge Resistant varieties Fungicides Timely sowing |
| Net blotch | Stubble, seed, volunteer plants | 15-25ºC free moisture |
Limited airborne | 10-90 emergence to maturity |
50+ | Crop rotation Stubble removal Treat seed Resistant varieties Foliar fungicides |
| Spot form net blotch | Stubble, volunteer plants | 15-25ºC free moisture |
Limited airborne | 11-90 first leaf to maturity |
30+ | Crop rotation Stubble removal Resistant varieties Foliar fungicides |
| Spot blotch | Stubble, seed, soil | 20-30ºC free moisture |
Limited airborne | 10-90 emergence to maturity |
50+ | Crop rotation Stubble removal Treat seed Resistant varieties Foliar fungicides |
| Powdery Mildew | Stubble, volunteer plants | 15-22ºC high humidity (85-100%) |
Airborne | 11-90 first leaf to maturity |
15 | Treat seed Resistant varieties Foliar fungicides |
Leaf rust (Puccinia hordei) and stem rust (Puccinia graminis tritici, secalis and tritici x secalis)
Traditionally the major airborne diseases of barley in Queensland. More likely to occur in wetter years or higher rainfall areas. Both can cause significant yield loss and quality downgrading. Grain yield can be reduced by up to 50% by stem rust and around 30% by leaf rust. As stem rust may infect barley and wheat, an epidemic could put both crops at risk.
The best protection from either disease is to plant resistant varieties and avoid planting very early or very late in the season. Barley occupies approximately 25% of the winter cereal area. As long as resistance levels of all winter cereals (especially wheat) remain high, it is not expected that major epidemics of stem rust will occur in barley. In emergencies timely application of fungicides can be effective.
Net blotch (Pyrenophora teres)
Has become the most significant disease of barley in the region and is likely to be a problem in wetter years and in stubble-retained situations.
It occurs in two forms: net form of net blotch (P teres f. teres) and spot form of net blotch (P. teres f. maculata).
The net form produces dark brown to black stripes on leaves and leaf sheaths of older plants and gives a characteristic netting pattern in juvenile leaves. The spot form of net blotch produces dark brown, round to elliptical spots on leaves and leaf sheaths that are often surrounded by yellowing.
High levels of either disease will kill leaves prematurely which may cause yield losses in excess of 30%. Growers are advised to avoid planting barley on barley where stubble is retained, as stubble-borne spores are the main source of infection for the new crop.
The net form of net blotch may be seed borne and grain from heavily diseased crops should not be retained for planting.
Net form of net blotch
Spot form of net blotch
Spot blotch (Cochliobolus sativus)
Favoured by warm wet conditions and is promoted by stubble retention. It can be seed-borne. Leaf symptoms are almost identical to the spot form of net blotch. Spot blotch may also cause discolouration of grains. This disease is more likely to be a problem in sub-coastal areas. Popular varieties are susceptible.
Spot blotch of barley
Barley Grass Stripe Rust (Puccinia striiformis)
Will infect some varieties of cultivated barley. Most current varieties grown in Queensland have good resistance and the disease is unlikely to be a major problem in the northern region in the near future.
Powdery mildew (Blumeria graminis hordei)
Often present in susceptible varieties, but generally causes only relatively small yield loss (usually less than 10%). Some seed treatments can give good early season control of powdery mildew but these may also shorten coleoptile length and cause emergence problems. Resistant varieties are the best means of control.
Some varieties may appear susceptible at the seedling stage but develop resistance to mildew during elongation. Where this occurs lower leaves of infected plants may take on a blotchy appearance which can be confused with other blotches caused by other diseases. Where powdery mildew is responsible fine mycelium is usually evident on the older leaves. https://www.daf.qld.gov.au/plants/field-crops-and-pastures/broadacre-field-crops/barley/diseases
Harvesting
Barley is generally harvested from October to late November. It can be expected to yield similar or better than wheat. The crop dries down well and desiccation is generally not necessary unless late weed growth needs to be controlled.
Barley is physiologically mature at between 30-50% moisture, which is well before it is ripe enough to mechanically harvest.
Mature barley does not stand weather damage as well as wheat. Therefore, it is important not to delay harvest. Lodging can be a problem and patches of unripe crop near headlands and low-lying areas should be avoided as they can contaminate the sample and downgrade it.
When ripe, winter cereals are easy to thresh, and harvest can begin at moisture as high as 20% although generally very little is harvested above 18% moisture. If harvested above 12.5% moisture, access to an adequate aeration or drying facility is necessary (see below for information on storing barley).
Suggested header setting adjustments for barley:
- Drum speed (rpm
- Conventional: 700-1000
- Rotary: 700-1000
- Concave clearance (mm)
- Front: 8
- Rear: 3
- Fan speed: high
As maintaining germination above 95% is vital, harvest and handling is of particular importance for malting barley. Even minor damage to the seed can affect the ability of the seed to germinate. Cracked grains, skinned or partially-skinned grains, and grains killed through damage to the germ, do not malt properly.
When examining a barley seed sample for damage, look at individual grains not just a mass of grain. Always examine grain’s back first and ignore the crease side. Severe cracking and germ damage are nearly always accompanied by a high degree of skinning. The most common causes for this are:
Drum speed too high – only use the slowest drum speed that will effectively thresh the grain from the barley head. A higher drum speed is needed when harvesting crops not properly ripe and can cause serious grain damage.
An incorrectly-adjusted or warped concave – the initial header settings should have the concave set one notch wider than for wheat. Check the setting frequently during the day. If the thresher drum speed is correct, concave adjustments should cope with the changes in temperature and other harvesting conditions met during the day.
The airflow may need to be increased slightly to obtain a clean sample.
The application of heat can also affect germination of grain and this should be carefully taken into account if artificial drying is intended for malting-quality barley.
Monitoring grain loss
Monitoring for grain loss should begin before harvest. A seed count on the ground of over 26 seeds in an area 10 x 100 cm means a loss of more than 100 kg/ha. After checking for any grain on the ground prior to harvest you should check after you begin harvest to determine any harvest loss. It is recommended that a minimum of 10 counts be taken and averaged.
Quality requirements
Most grain purchasers will base their quality requirements on NACM A standards. For feed barley grain is required to meet sceenings and hectolitre weight specifications. For malting barley, as well as screenings and hectorlitre weights there are requirements for retention (above the 2.5 mm screen) and protein.
Malting barley requires moderate protein levels of between 9-12% The malting industry reports protein content at 0% moisture (dry) which will be 1-1.5% greater than the ‘as is’ basis, commonly used for feed grain. In line with malting industry standards, Graincorp reports all protein figures at 0% moisture basis. Feedlots generally use the ‘as is’ figure.
Growers should confirm receival standards with Graincorp or their local grain merchant. Specification sheets are usually available from July each season and include all relevant information. Other purchasers of barley grain may use different specifications. Graincorp provides a grower harvest information kit, including local contacts, contract options, warehousing conditions, grain protection strategies and more. Other purchasers of barley grain may use different specifications.
Storage
Barley is more susceptible to insect damage than many grains. When storing malting barley it is important to be aware of a few specific issues that will ensure the grain maintains its malting qualities.
Firstly, and most importantly, maintaining germination of the grain at over 95% is vital for malting barley. Germination can be affected by grain temperature, grain moisture content and insect infestation. Any grains failing to germinate during malting will contribute to poor malt quality and brewing problems. Generally, high grain temperatures and high grain moisture content can be a cause of low germination (less than 95%). Insect infestation can have a similar effect. In an ideal world, malting barley would be kept free of insects, in aerated storage at grain temperatures of 10°C-20°C with a moisture content of less than 10.5%. However this is not generally practical and being aware of the interaction between moisture and temperature is important.
| An indication of the interaction between moisture and temperature. | ||
| Barley moisture % | Storage temperature | Potential storage period |
| <10.5 | 10oC-20oC | Very long 12-18 months |
| 20#C-30oC | Moderate 6 months | |
| > 30oC | Short 3 months | |
| 10.5 – >11.5 | 10oC-20oC | Long 12 months |
| 20#C-30oC | Moderate 6 months | |
| > 30oC | Short 3 months | |
| 11.5 – > 12.5 | 10#C-20oC | Moderate 6 months |
| 20#C-30oC | Short 3 months | |
| > 30oC | Very short < 3months | |
| > 12.5 | 10oC-20oC | Short 3 months |
| 20#C-30oC | Very short < 3 months | |
| > 30oC | Perhaps 1 month | |
Temperature
If possible, keep barley grain at between 10 and 20°C. Above this temperature germination and malt quality can become affected. Between 20°C and 30°C short to medium-term storage presents some risk but once temperature of the grain reaches over 30°C germination is likely to be affected. Temperatures significantly above 30°C will cause grain to become non-viable. Warning: This also applies for drying grain that needs to maintain its germination (malting or seed crops). It should be dried slowly at low temperatures.
Moisture
The moisture of grain in storage will affect its ability to maintain quality over time. The lower the grain moisture the more stable its storage ability. However, in practical terms it is more economical to store grain at around 12% moisture content.
Insects
Keeping the grain free from insect infestation is also another important aspect. As chemical residues can cause problems in some markets, treatment should be carefully considered. However, if treatment is warranted, and there is access to sealed silos or fumigation bins, fumigation with phosphine is the preferred treatment. Where fumigation is not possible, a combination of fenitrothion and methoprene (IGR or Diacon) is recommended. For rates and application methods it is important to follow the manufacturer’s recommendations but as a guide:
up to 6 months- 6 ml /tonne of fenitrothion plus 5 ml/tonne of methoprene (IGR 200g/L)
up to 9 months-12 ml/tonne fenitrothion* plus 5 ml /tonne of methoprene (IGR 200g/L)
*Note there is a 90-day withholding period applied when using 12ml/t fenitrothion
Any chemical treatment of grain should be declared at delivery. Use of Reldan and Carbaryl are specifically excluded for malting barley.
Importance of aeration
Aeration is important as it evens out the moisture, cools the grain and helps reduce hot spots. Cooling the grain can also help to reduce insect infestations.
Quality requirements
The minimum protein level acceptable for malt-grade barley is 9.0. Malt protein content is reported at 0% moisture (dry) which will be 1 to 1.5% greater than the ‘as is’ basis, commonly used for feed grain. In line with malting industry standards, Graincorp reports all protein figures at 0% moisture basis. Feedlots generally use the ‘as is’ figure.
Growers should check receival standards with Graincorp Australia or their local grain merchant. Specifications are updated each season and include all relevant information. Other purchasers of barley grain may use different specifications.
Post harvesting Handling
Among cereals, barley is most preferred for malt, as its husk protecting the coleoptiles (acrospire) during germination process and provides aid in filtration, firm texture of grains and its amylases activity makes it unique for malt recovery. In context of the nutritional values barley grains have higher soluble dietary fibre and lower low density lipoprotein (LDL) content than that of wheat. Soluble fibre has a cholesterol lowering property and LDL cholesterol is the fraction associated with increased risk of heart diseases.
Storage is an essential interim operation in the food pipeline that moves crops from producer to processor and foodstuffs from processor to consumer. In developed countries storages losses on an annual basis are usually less than 1% while in developing countries these have been estimated conservatively as 10-15%. Losses of biological origin such as grain or insect or limited drying due to aeration of grain in storage are common. These losses can be minimized by adopting good package and practices and proper post harvest handling of the grains. So the thorough knowledge of storage pest and other harmful agents in this regard is necessary. Storage pest and fungi of barley are given below-
Storage pests of barley
| Order | Scientific Name | Common Name |
| Coleoptera | Trogoderma granarium | Khapra beetle |
| Rhyzopertha dominica | Lesser grain borer | |
| Oryzaephilus surinamensis | Saw toothed grain beetle | |
| Tribolium castaneum | Red flour beetle | |
| Sitophilus oryzae | Rice weevil | |
| Sitophilus zeamais | Maize weevil | |
| Lepidoptera | Sitotroga cerealella | Angoumois grain moth |
| Plodia interpunctella | Indian meal moth | |
| Acarina | Acarus siro | Grain mite |
Storage fungi
The most important fungal species causing spoilage of barley in storage belong to the genus Aspergillus, Penicillium, Rhizopus, Mucor etc. Degree of infection and losses caused by these fungi largely depends on availability of free moisture, relative humidity and temperature etc.
Some of the practices for safe storage of barley grains are given below:
Better package and practices
Most of the storage micro-organism and pest favours low quality, shrivelled and broken grains because it is easily penetrable to them. So the better package and practices and proper harvesting procedure should be adopted to ensure the good quality seed with minimum breakage to the grains.
Drying
Many storage diseases and pests favour moist grains in storage. These include micro-organisms and other storage pests. So the barley grains must be dried before putting in granaries. For this purpose, harvested crop is left in open and sunny place for drying and appropriate care should be taken of aeration.
Cleaning
Barley grains are important for malting and feeding industries. During the cleaning process materials should be separated as stones, weed seeds and broken grains.
Safe storage
Farmers should keep the crop in closed areas in depots made by brick, cement, and wood etc. The storage facilities should have sufficient isolations and controllable atmosphere to create the most adverse conditions for the development and multiplication of micro-organisms and pests. Care should be taken of unbalanced humidity, temperature and O2 /CO2 levels which allow infestation of the stored grains by micro-organisms (as fungi), insect pests and rodents. Generally, barley is stored for a short period under shelter or in depots in order not to be affected by rainfall or other adverse climatic events. Horizontal type adobe depots are used by rural people as their economic status permits only this type of depots. The insect pests existing in the store can be destroyed before the grain is stored with the use of chemicals i.e. Malathion etc. Further, the modern silos can be a better option for storage of big quantities to be used for commercial purposes.
Rodenticides:
Proper care must be taken as not to leave any holes or cracks on the walls of storage. Mechanical traps with attractive food such as chapatti can be used to trap the rats in the rural areas and small farms. However, medium size farmers tend to use rodenticides in various formulations. For example, the rodents can be chemically controlled through placement of pellets of the poisonous rodenticides (Zinc phosphide 80-95%) in the grain stores.
Chemicals/ protectants:
Diatomaceous earths, silica aero gels, and activated clays in the form of inert dust act as toxic and repellent insecticide. The insecticides acting as effective grain protectants include Malathion 50% EC (1:100 with water @ 3 litres/100 sq.m) and Dichlorvos 100% EC (1:300 with water @ 3 litres/100 sq.m).
Fumigation:
It is necessary to fumigate the stores to destroy storage pest or decrease their population. Various agents can be used for fumigation for example Phosphine (@ 2 tablets/10 q) etc.
http://www.krishisewa.com/articles/33-postharvest/32-barley_postharvest.html
Processing
Milling of Barley
Barley is millet to make blocked barley, pearl barley, barley grots, barley flakes and barley flour for human consumption. Removal of the hull or husk of barley, which is largely indigestible is an important part of the milling process.
Intrinsic qualities:
The milling is done in barley to achieve:
- Absence of sprouting.
- Absence of discolouration due to weathering.
- Freedom from fungal attack and insect infestation or damage.
- Soundness of appearance.
- Absence of undesirable aroma or flavour.
The harder types of barley is best for milling purposes because the hull and bran can easily be removed from endosperm by superficial abrasion and yielding particle will retain the shape of the whole grain. The softer grains are not better because they would tend to fragments, leading to a reduction in the yield of first quality products.
Barley for milling should have as low as hull intent as possible. The presence of damaged grains lowers the quality of milling barley. Such grains frequently reveal areas of exposed endosperm where fungal attack may occur leading to discolouration and intrigues discoloured particles to the finished products. Thin grains also lower the milling quality with a higher hull content than normal they make a small contribution to the yield of milled products.
Operations
the sequence of operations in barley milling may be summarized as follows.
- Preliminary Cleaning: Barley is cleaned on machines similar to those used for wheat cleaning, viz. milling separators, drier cylinders or indented dishes, and aspirators. The sizes of sieve aspirators and indents are modified for the comparatively larger size of barley grains.
- Conditioning: Conditioning consists in adjustment of moisture content to about 15% by drying or damping and resting for 24 hour.
- Bleaching: Barley is used to bleach with moisture and sulphur dioxide. Blocked barley is fed into a vertical earthenware cylinder. Into which steam and sulphur dioxide are injected. The quantities used are 1-2% of moisture and about 0.04% of sulphur dioxide and solution of sulphurous acid (H2SO3) or of sodium disulphide (NaHSO3) can be. The treatment takes about 20-30 min time, after that the barley is binned for 12-24 hour for the bleaching to take effect. Excessive quantities of sulphur residues in the final product should be avoided.
- Blocking and Pealing: Both blocking and pearling of barley are abrasive scouring processes differing from each other merely in degree of removal of the superficial layers of the grain batch machines or the rate of throughput in continuous working machine.
- Aspiration: Aspiration of the pearled grain to removes the abraded portions and cutting of blocked barley into portions known as grits and it is similar to those methods done for aspiration of oatmeal. In Germany, the blocked barley is first cut into grits, the grits graded by size and then sounded in the pearling machine.
- Polishing:The pearl barley is polished on machines similar to those used for pearling but equipped with stones made of hard white sandstone instead of emery composition. The average yield of barley is 67% of the whole barley.
- Steam Cooking and Flaking:Barley flakes are made from pearl barley by steaming and flaking on large diameter smooth rolls.
- Drying: The flakes are dried to about 10.5% moisture content before packing. Barley flakes are made from pearled barley has been used as flavouring ingredients in specially breads in the USA.
Pearl barley is used for sups and dressings and for the manufacture of puffed barley, a read to eat breakfast cereal. Pearl barley blocking removes part of the husk, this process must be accomplished with the minimum of injury to the kernels. The pearling carried out in two stages, removes the remainder of the husk and part of the endosperm. The three processes remove about 5%, 15% and 11%, respectively to yield a final product representing about 67% of the grain.
Three types of blocking and pearling machine are in general use:
(i) A fetch machine consisting of a large circular stone, faced with energy cements composition and rotating on a horizontal axis within a perforated metal cage.
(ii) A continuous working machine consisting of a rotator faced with absorsive material rotating on a horizontal axis within a semi-circular stator lined with the same material, the distance between rotor and stator being adjustable.
(iii) A continuous working machine comprising a pile of small circular stones rotating on a vertical axis within a metal sleeve. The annular space between the stones and the sleeve occupied by the barley being strongly aspirated. The barley bolls between the rotator and the stationary part of each machine in bouncing from one surface to the other the husk is split or subbed off. The degree of treatments is governed by the abrasiveness of the stone flung by the distance between rotor, and station and by the time of treatment in is also a starting material for the manufacture of barley flour. Milled barley are also used for extruded food snacks as croutons and salad dressing as crunches for nut substitutes.
Barley Flour
Barley flour is milled from pearl barley, blocked barley or unpearled hull less barley. Optimum tempering conditions are 13% moisture content for 48 hours for pearl barley, 14% moisture content for 48 hours for unpearled hull less barley. The milling system uses solar mills with blunted and smooth rolls and plansitfers.
When blocked barley or whole barley is used for milling barley flour, due allowance must be made for the greatly increased quantity of by products, which would otherwise hope the system. Barley flour is also a by-products of the cutting, pearling and polishing processes.
| Barley Types | Extraction Rate |
| Pearl barley | 82% |
| Original whole grain | 55% |
| Blocked barley | 59% |
A blend of hull less barley and wheat can also be milled at the ratio of 10:90 to 20:80. When barley flour was blended with wheat flour in ratio of 10:90 to 30:70, bread characteristics were better with hull less barley flour than with hulled barley flour, but bread quality deteriorated as proportion of barley flour increased.
Barley flour is used in the manufacture of flat bread for infant food and for food specialties. It is also a component of composite flours used for making yeast raised bread.
Pre gelatinized barley flour which has high absorbent properties provides a good binder and thickener. Combining pre gelatinized barley flour with barley crunch makes barley breading.
The coarse by products from the blocking process are fragmented on a chamber mill and the ground product combined with the residues from the two peeling operations for use as animal feed.
Malted Barley Flour
Barley malt is ground or milled to make malted barley flour. Malt flour is used as a high diastatic supplement for bread flours, which are low in materials diastatic activity, as a flavour supplement in malt loaves and for various other food products.
Air Classification: Malted barley flour can be our classified to yield protein rich and protein poor fractions. The former used in the food industry, while the later is used to make unique beer.
Other products derived from malt include kibbled malt, malt extract and cereal syrups. The major food uses for malt products and cereal syrups are in bread, biscuits, crackers, crisp breads, breakfast cereals, infant and invalid foods, matted food drinks, pickles and sauces, sugar confectionary and vinegar.
Molting
Molting is a controlled natural process rather than a manufacturing operation. Essentially barley kernels are allowed to grow under precisely defined conditions in order to bring about specific, desirable changes in the physical and chemical properties of the kernel. Growth is then stopped by removal of water. Flavour components are developed by gently heating and curing the malt.
Finished malt resembles barley, but only superficially. Within the kernel, natural enzymes formed and stimulated by controlled moisture, aeration and temperature have:
- Broken down cell wall material in the endosperm,
- Rendered some of the protein soluble in water,
- Started to degrade some of the starch granules fermentable sugars.
Barley is cleaned, sized, segregated by variety and protein content and stored for several months to break any dormancy. The amount of water-soluble extract obtained from malt is dependent to a large extent on the amount of starch in the kernel. From this extract, brewers produce beer. Low protein (13% dry basis or lower), plump kernels have a higher proportion of starch and other factors being equal produce a higher quality brewer’s malt.
The following steps are involved :-
- Cleaning and Grading: On intake, barley is cleaned to remove dust, chaff, weed seeds, thin barley and other grains. Cleaned barley is graded according to size plump and medium grades of barley, retained in sieves with slots 2.5, 2.4, 2.2 and 2.0 mm wide or 2.2 mm sieve is too thin for malting and is sold as feed.
- Steeping: Growth is initiated by the absorption of water into the kernel in conical bottomed steep tanks. Water at 12-160C and air, respectively are provided to barley over a period of 40-48 hour. Water enters the embryo through the micropyle, a small opening, until the moisture content of the kernels rises to 44 to 46%. The water is changed every 6-8 hour and is never recycled. Molt houses create a significant volume of effluent with a high BOD. Compressed air bubbled through the steep agitates the barley to ensure all surfaces are washed.
Gibberellins, plant hormones, are synthesized by the embryo and diffuse to the aleurone layer of the barley kernel. Here they stimulate the production of the hydrolytic enzymes capable of degrading barley starch granules, protein and nucleic acids. Enzyme production also takes place in the embryo.
Later aerations remove the carbon dioxide from as a respiratory product of initial growth
- Germination: From the steep tank, the barley falls by gravity or is gently conveyed to the germination vessel. Over a period of four days at 13-160C and 100% humidity the barley grows. The bed is gently turned by machine to prevent the soot lets from malting and to promote uniform growth throughout the bed. Using large volumes of air and water sprays, the temperature is controlled and carbon dioxide removed. Germination is considered complete when the endosperm is fully modified which means:
(i) The cell walls are largely dissolved to expose the starchy interiors of the cells.
(ii) Those catabolic enzymes are formed which will convert high molecular weight carbohydrates to low molecular weight carbohydrates and sugars.
(iii) Degradation of some proteins to soluble peptides has begun. These peptides will nourish yeast in the fermentation process; some will remain in the finished beer giving it mouth feed and tenure. Fully germinated barley is called green malt. Germination is carried out in drums on rotating floors, in salad in boxes or the wonder houfen system
- Kilning: Kilning can be carried out in the same vessel as germination. To save energy, kilns are often arranged on two levels, one directly above the other. Initiate drying takes place in the upper kiln, using the residual moisture removing capacity in the warm air coming from the lower kiln. Air fully laden with moisture is then exhausted to the atmosphere.
To prevent denaturation of the enzymes required by the brewing process, green molt is gently dried. The drying air temperature is increased from 500C through various levels to a final temperature around 800C. Air forced through the fed gradually lowered the moisture content of the malt to 4%.
Later stages of kilning are referred to as the curing process, during which most of the flavour components of malt are generated. These are predominantly heat induced chemical compounds called maillard reaction products; they characteristically develop when amino acids and sugars are heated together. Following kilning the brittle rootlets are easily removed and role as a high protein (75% dry basis) feeds supplement for livestock.
The malt is stored, often for reversal weeks to regain homogeneity and equilibrium, prior to blending and shipment.
The yield of malt from barley is about 75% some typical losses consist of:
Cleanout from raw barley – 7-9%
Respiration during steeping and germination – 4-5%.
Drying (barley, 13.3%, malt 4%) – 9-10%
Malt rootlets and hulls – 3-4%
- Malt Analysis and Shipment: Control of all aspects of the steeping, germinating, and kilning process must be reliable and precise. Variances as small as 1% in the moisture level or 10C in the temperature have a significant effect on the analytical values of the final malt.
Use of Malt
Special malts such as caramel, black, amber roasted, and Munich malts impart colour and additive flavour to beer. They are produced by various degrees of roasting, to the concomitant detriment of the enzymes. Peat malt has the savor of peat smokes. Crystal malt is green malt rapidly heated. The interior is glassy and the taste is luscious.
Distiller’s malt with its high enzyme activity and less emphasis on flavour is produced by kilning at low temperatures. Hopped malt extracts are used in specially breweries and home brewing kits.
Other uses for malt are in baking, confectionary and breakfast foods. http://food-science-and-technology.blogspot.com.ng/2012/04/processing-of-barley.html
Export
Barley Exports by Country
Barley is a food ingredient used in soups, stews, breads and beverages. For example, this major cereal grain is a component for health foods. Barley also is used to ferment malt beer. A member of the grass family, barley has an additional food use serving as animal fodder.
Global sales from barley exports by country amounted to US$5.9 billion in 2016. Overall, the value of barley exports was down by an average -25.7% for all exporting countries since 2012 when barley shipments were valued at $7.9 billion. The most dramatic year over year decline was from 2015 to 2016 when the value of exported barley dipped by -25.4%.
Among continents, European countries accounted for the highest dollar worth of exported barley during 2016 with shipments valued at $3.7 billion or almost two-thirds (62.9%) of total barley exports. In second place were Oceania exporters (principally Australia) at 19.2% while 10.5% of worldwide barley shipments originated from Latin America. Smaller percentages originated from North America (5.4%), Asia (2%) and Africa (0.03%).
The 4-digit Harmonized Tariff System code prefix for raw barley is 1003 (which is the focus of this analysis). The HTS prefix for rolled, flaked, pearled or otherwise worked barley is 1104.
Barley Exports by Country
Below are the 15 countries that exported the highest dollar value worth of barley during 2016:
France: US$1.6 billion (20.3% of total barley exports)
Australia: $1.3 billion (17.1%)
Russia: $944.3 million (12.2%)
Ukraine: $653.4 million (8.5%)
Germany: $560.4 million (7.3%)
Canada: $353.7 million (4.6%)
Argentina: $348.8 million (4.5%)
Romania: $333.6 million (4.3%)
United Kingdom: $315 million (4.1%)
Denmark: $231.6 million (3%)
Hungary: $142.2 million (1.8%)
Kazakhstan: $104.4 million (1.4%)
Sweden: $99.7 million (1.29%)
Czech Republic: $99 million (1.28%)
United States: $79.2 million (1%)
The listed 15 countries shipped 94.1% of global barley exports in 2016 by value.
Five of these countries increased their barley exports since 2012: United Kingdom (up 80.5%), Kazakhstan (up 42.9%), Romania (up 12.2%) and Germany (up 11.5%) and Hungary (up 10.8%).
Those countries that posted declines in their exported barley sales were led by: Denmark (down -55.6%), Russia (down -52.7%), Ukraine (down -46.9%), Canada (down -39.5%) and Sweden (down -32.1%). http://www.worldstopexports.com/barley-exports-by-country/
Barley Specifications
