Grain & pulse samples
1. General Introduction
Grain is grown and processed for many different industries and end-uses. Livestock feeding, brewing, distilling & biofuel industries all have different processing requirements. Irrespective of the industry, the grain is processed to break the tough outer husk. This allows for the energy content of the seed to be harnessed and utilized.
In situations where the grain has not being correctly processed and the husk remains intact, its energy will not be fully released. Poor economic return is the net result of this.
By breaking the husk of the grain, digestion in livestock will be improved and fermentation in the alcohol industry will be maximised.
2. Specific Grain Processing Systems for Ruminant Farm Animals.
There are several methods of processing grain applied in the livestock feeding sector. Choosing a suitable method will depend on the type of grain, its moisture content, storage facilities and type of animals being fed. The main methods are:
• Dry Rolling (10-17% low moisture content). This produces a varying range of flattened samples. The husk is broken, releasing the endosperm or flour. End-samples will vary from flattened to finely broken depending on the moisture content and type of roller used. Water is sometimes added to reduce dust: In this situation, an additive may be necessary to ensure storage stability.
The recommended feed rate for a dairy cow in full production is 15-20% of their diet on a daily basis. For beef animals this feed rate can vary from 15-60% of total ration. Popular grains used are barley, wheat, oats and triticale. Corn Maize is also a popular animal feed.*
Alkaline / Acid Treatment (17-25% mid moisture content). Grain is lightly rolled or cracked and the additive, (either alkaline or acid-based) is accurately incorporated. Certain alkaline preservation systems can be chosen to enhance the protein content of the grain. Feed rates for a dairy cow are between 20-25% of the total ration. Beef animals feed rate vary between 15-80%. Popular grains used include barley, wheat and maize.*
• Crimping (25-45% high moisture content). In this situation grain is harvested at an immature stage and is lightly ‘crimped’ or ‘bruised’. A suitable additive is required to enhance fermentation, thus allowing for long term storage. Feed rates for a dairy cow range from 18-25% of total ration; while for a beef animal they can be between 15-60% of the feed. Popular grains used are barley and wheat.*
• Grinding (8-16% low moisture content). The grain is sheared, to varying degrees of fineness, producing a finely ground product from 0.2 – 2.0mm particle size .This method is widely used in the alcohol and pig & poultry industries. The finely ground grain allows for easy pelleting for the pig, poultry and cattle feeding sectors. For dairy cows the feed rate ranges from 10-15%; and for beef animals, 20-25% of total rations. Common grains used are barley, wheat and maize.*
• Flaking (20-22% mid moisture content). Preparation steps depend on the type of flaking process.
Cold rolling: steeping the grain for a period of time, and presenting them uniformly to the large diameter, slow rotating rolls.
Steam or infra-red heating: Grain is heated to temperatures of 100-120 degrees for a period of time, 10-20 minutes steam, 25-55 seconds for I/R. (The grain starch levels peak & are part-gelatinised): The grain is then presented uniformly to the large diameter, slow rotating rolls. Grain has being gelatinised or flaked with increased protein levels. Heat & moisture should be removed immediately to prevent retro-gradation. Feeding rates for dairy cows range between 15-25% and for beef cattle 15-55% of total rations. Most popular grains used are barley, wheat, maize and oats.*
• Kibbling (12-16% low moisture content). This method produces a ‘cut sample’ with no shear effect on the grain. It is generally fed to younger cattle where dust is a concern. Processed grain can be incorporated as part of a pelleted feed: This facilitates the inclusion of a higher percentage of grain compared with ground grain. Most popular grains used are barley and maize.*
In all cases where grain is being fed to ruminant animals, – particularly at higher rates, – it should be included in the total ration as part of a correctly balanced diet. Particular attention must be given to providing the correct levels of digestible and long fibre; plus crude protein, mineral & vitamin supplements.
3. Monogastric Farm Animals
Monogastric animals have a digestive system that requires their feed to be finely ground. Particle size is dependent on the animal being fed. If the processed grain is being fed directly to the pigs the average grist size is 600-800µm. If the feed is being pelleted the grain should be ground finer to 500-600 µm particle size. This aids the compression process.
Depending on the Pig’s age, the particle size can also vary. Piglets require finer grist, viz: 450-600 µm; while Sows thrive on a courser grist, viz: 800-1200 µm.
(Certain cereals tend to paste if processed too finely, particularly wheat).
Feeding grains to pigs that are correctly processed, – (and are part of a balanced ration), – will result in significantly improved feed conversion efficiencies.
Feeding grains to pigs that are too fine or too coarse for their age, will reduce feed conversion efficiency and daily live-weight gain. This may also lead to respiratory problems, gastric ulcers, increased feed processing costs.
[Ground soya bean, maize, barley and wheat are all excellent feed ingredients for pigs. But they must be included as component parts of a balanced ration].
4. Brewing and Distilling
Malting barley (though sometimes Rye) are the most popular grains used in the distilling and brewing industries.
Grain is steeped until it reaches 40-44% moisture content. It is then allowed to ‘sprout’, before being dried and roasted until it reaches 4-5 % moisture content
The grain grist size for producing alcohol varies from 600-800 µm to a coarsely broken particle size, Increased processing will improve extraction, but a finer grist can effect the run off process time.
** All the above will be relative to the Type of Larger,Ale,Stout being brewed or type of Malt being distilled.
5. Other Raw Materials
A large range of raw materials can be processed using Wakely Engineering Milling Technologies. Wakely Milling Machines can be adapted to process all varieties of feed grains; dry pelleted feeds; seaweeds; fish shells; minerals and wood pellets, etc.
Whatever industry you are in, – (farming, agricultural contracting, livestock feed milling, brewery, distillery or biomass sectors), – the Wakely Engineering Milling Machinery Range is the most comprehensive on the market. We have a renowned reputation for engineering quality of machinery; production efficiency; service, reliability, and end-product quality, etc.
Our active sound suppression system and ‘no roll-to roll-contact’ guarantee a quite & pleasant working environment where Wakely Mills operate. The Wakely Through-put Calculator and our wet / dry preservative applicators complement our unique range of Wakely Grain Mills.
With Wakely Engineering Milling Machinery Range processing Grain & Other Raw materials across the Continent of Europe, South Africa & Australasia, you can be confident that our knowledge in milling guarantees a Superior sample every time.
*Please Note! Our recommendations for feeding farm animals are essentially general and introductory in nature. Livestock Farmers should contact their Farm Advisor for specific instructions to suit their own particular conditions and requirements, etc.