Focus on Artisanal Wheat & Ancient Grain Milling

Wheat – that grain used for our daily bread and descendant of the ancient grains originally grown and selected in the fertile crescent and the mainstay of the agricultural revolution, in modern times was the domain of large scale industrial mills, very often due to centralized government policies and bread subsidies to the masses. The village wheat flour mill practically disappeared.

Since the early 1990’s ABC Hansen Africa piloted the way for artisanal milling of flour in plants of 12 to 75 tons per day and focusses on high value, low volume, highly efficient milling.

Ordinary commercial wheat flour can broadly be classified as follows:?

• Cake Flour:
  • Protein 8-10%; Particle size < 160 micron; Ash < 0.65%. Colour – white with very few noticeable bran specks. Extraction 50-60%. Used for confectionery baking, often with baking powder rather than yeast due to lower protein. White Bread flour: Protein 10-12%; Particle size < 212 micron; Ash < 0.78% Colour white with some noticeable specks. Extraction 70- 78% Used for baking most yeast product where a good rise is required. Brown bread flour: Protein 9-11% Particle size 85%< 212 micron; 15%> 212 micron. Ash – not measured.
  • Colour white with large flakes of bran.
  • Used almost exclusively for brown yeast bread.
• Self-raising flour:
  • This is simply low protein (below 9%) cake flour with baking powder added to it to allow for easy baking of non-yeast products and is a home-bake, small package value adding product by industrial mill.
• Industrial flour:
  • Protein – not measured, Particle size < 300 micron. Ash – > 1%.
  • Off-white flour with many bran specks.
  • Used in brown bread mix as well as for biscuits and other confectionery products where its off-white colour and rise is not important. Also used as filler in foods and sweet meats, soups, gravy etc.
• Semolina
  • This type of flour is coarse – normally above 300 micron and below 1mm and is traditionally made from durum wheat – a wheat type with very low gluten (the protein in wheat that lends wheat its “stretchability” needed to expand in the fermentation process while retaining the “bubbles” intact. This is used in manufacturing pasta and cous-cous for instance and is separated from fine bran by air and vibration through a machine called a purifier.
• By-products:
  • Wheaten bran used in animal feeds and fillers. Pollard (very fine bran) used as fillers in food such as processed meats, biscuits etc. Screenings used as animal feeds.

Our focus however is on Stone Ground Artisanal Flour milling…..

StoneGround* artisanal flour:
As the name indicates, this can be virtually any flour that works for the application it is milled for, be that for confectionary, artisanal (rather than industrial) bread, flat breads, pita breads, pizza crust, sourdough breads etc. and is normally of higher ash value** than industrial white bread, has a colour varying between white, slightly creamy up to almost Khaki coloured and has the same particle size as cake flour and white bread flour, has the wheat germ (with its many nutrients) intact, is not chemically bleached and has many variations the miller can apply to make custom flour for his ultra discerning baker-customer.

Ancient grains such as spelt, Khorasan wheat (Kamut), freekeh, bulgur, farro, einkorn, emmer; barley, oats, rye and the pseudocereals quinoa, amaranth, buckwheat, and chia for which a limited upper end demand exist, can be profitably milled with a stone ground artisanal milling system.
** Ash content denotes the percentage of minerals, primarily originating in the bran, remaining after the flour has been incinerated, therefore providing an index as to the bran content in the flour and subsequently its “purity” in terms of advanced refined carbohydrates – nothing to be really proud of for those seeking healthier food products.

• Why an Artisanal StoneGround Mill?
  
  • Stone Ground* flour is known to absorb more water due to the higher starch damage millstones inflict on the grain which in turn provides a softer mouthfeel in the final product.
    It has more fine bran particles allowing better digestion and reducing the incidence of colon cancer for instance. It can be processed to have as low ash content as industrial white bread and cake flour but it defeats the object.
  • It has minimal contact with steel in die grinding process and in smaller plants specifically, steel roller mills need not be used at all. Rollers are primarily used to increase low ash content yield for those millers who still rely on having to be competitive with the large industrial mills.
    
  • It retains the wheat germ with its all wholesomeness.
    
  • It is never chemically bleached neither are chemicals and enzymes added to improve poor flour’s baking quality.
    
  • The artisanal miller can produce flours and flour blends that suit a variety of baked products and lend a special taste, appearance, and mouthfeel to such custom products.
    
  • An artisanal mill in your town encourages local industry, provides local employment and entrepreneurship, supports organic and high-quality grain growers, encourages healthy eating habits, and contributes to the community.
    
    
    

So, what equipment should be used to produce StoneGround artisanal flour?
To produce StoneGround* flour, a miller needs the following equipment:
An intake system for wheat as well as storage in at least 3 silos or bins, from which a grist is blended to ensure the same quality flour over a longer period and to optimize on raw material cost.
A day bin in which the grist is placed prior to milling is also important.
ABC Hansen Quail* II Cleaner and aspirator, dampener and conditioning bins where cleaned and moistured grain is detained for 24 – 36 hours prior to milling ensures high quality mature flour.
A scourer or polisher – in the case of ABC Hansen’s mills a Tempest* Stone Grain Polisher removes some of the outer bran and dirt collected on the grain kernels.
A Hurricane* roller mill with four roller passages may be used to remove all the bran from the endosperm providing for a whiter flour. Alternatively the wheat can be milled through several passes over StoneGround* stone mills until the endosperm is completely milled down.
If a roller mill us used, high capacity and a cleaner flour can be achieved. Once flour and bran is screened out, the middlings (coarse endosperm particles) are then introduced to the stone mill or several stone mills followed by sifting processes.
An ABC Hansen blender is always a requirement to blend bran and flour at the correct proportions or rye flour and wheat flour or any of the other ancient grains for specialty flour.

*StoneGround stone mills is a registered brand of ABC Hansen fitted with the world-famous Danish Engsko stones (circa 1900).

• Tempest grain polishers, Hurricane roller mills, Quail cleaners and Hippo hammer mills are all registered brands manufactured by ABC Hansen

OILSEEDS PROCESSING

Why pellet?

The most obvious reasons are:

•             Better digestibility;

•             Less waste during consumption and transportation & storage;

•             More assured intake of all elements;

•             Conversion of powdery / unpalatable ingredients to concentrated feed and ensuring separated mixed ingredients are all consumed;

•             Higher bulk density and therefore less storage & transportation space;

•             However, the most compelling reason for pelleting is that the gain per kilogram feed increases with pelleted feed vs mash.

•             It has been innumerable times proven that swine specifically gained on average 113 grams per day more weight being fed pellets than the same ration and amount of mash. Poultry, cattle and small stock likewise has similar gain advantages.

•             In the case of sheep and goats, which are notoriously picky eaters, the full ration and waste are also important reasons to pellet feed.

What is the cost of pelleting?

Pelleting should not add more than R103 (US$6-7)  per ton to your feed, which includes electricity, maintenance, wear and tear, and operator cost.

At one pig’s average consumption of 2.5kg feed per day, a ton of feed would last 400 days or would finish approximately 4 pigs to 80-90kg. With 113 grams additional weight per day on pelleted feed, the said pigs would gain 51 additional kilograms, being more than R1,200 higher income at slaughter at R24 per kg live weight.

Therefore a 1,165% gain over the additional operational cost.

Can cost be reduced & efficiency increased by adding steam?

Yes it can. Steam lubricates the product for faster production, the lubrication extends die life, it reduces energy costs and gelatinizes starch for higher nutritional value. Fines also bind better and less pellet breaking occurs.

Heating mash with steam to 75 degrees C will reduce friction heat no less than 30% and reduce motor amps by 20% while increasing capacity fourfold. The amount of roughage vs grain and protein, molasses content etc. would however play a role in these equations.

While steam addition at 50kg per hour or 5% on a 1,000kg/hour mill, an additional electricity cost on around 37kW can be expected. This however would be easily offset by the higher production and lower replacement cost of dies as well as lower electricity per kilogram produced on the pellet mill itself and a payback of less than 6 months.

An electric steam generator can be purchased from ABC Hansen for around R119,400 VAT Included. This steam generator will produce 50kg. of steam at working pressure of 101 PSIG (pounds per square inch guage) operating at 4 – 94 PSIG (or around 7 Bar) with 3 x 12kW = 36kW elements plus a 0.55kW pump and is a perfect match for our MPEL400  and one or two MPEL260 pellet mills.

What does a pelleting system consist of?

1. Supply bins and intake: With free flowing grain and other free flowing materials hopper bins are normally filled by elevator and conveyor from bulk trucks. Bagged free flowing materials may also be discharged into a reception bin and conveyed into a supply bin. Non-flowing items are normally offloaded in heaps and collected with front end loaders into reception bins on load cells prior to conveyance to the pre-blending bin. Should these non-free-flowing materials be loaded into a bin, a roto-flow vibrating device needs to be installed below the bin. The supply bins should have at least 5 times the capacity of the pre-blending bin.

2. A scalper fitted with magnets to screen out large particles and tramp steel should be part of the intake system in order to prevent damage to all equipment down-line.

3. Milling: It is preferable to grind down the raw materials to a size is at most equal to the pellet die aperture and preferably smaller. Particles any larger would imply that the pellet mill would be tasked to grinding these particles resulting in higher wear and tear, higher electricity use and lower capacity. A Hippo hammer mill should be selected in the correct capacity. This range of mills includes

4. Pre-blending bin: This is preferably located over the blender allowing the complete ration to be made up and dumped into the blender once the previous blend has been unloaded. This increases the number of batches to be mixed per hour.

5. The blender: The size of the blender together with the speed of conveyance into the pre-blending bin and the speed of unloading  determines the capacity of the mill. Blender capacity in liters would presume that the blender is filled only to the shaft and the density of the mix is then calculated to determine the kilogram capacity of the blender. A 3,000 liter blender filled to the shaft at around 1,500 liters, with a density of 0.6 would determine a mixing capacity of 900 kilograms per batch.

6.Post blending bin: Where the batch is immediately conveyed to subsequent to mixing, usually at the fastest capacity possible to ready the blender for the next mix and is at least two or three times the capacity of the blender and matching the capacity of the pellet mill times 3 to allow for the clearing of blockages, change of die and other non-scheduled and scheduled break in continuous production.

7. The conveyor feeding the pellet mil, allowing for minute speed selection to allow the mill to operate at most efficient capacity.

8. The steam generator with steam addition to the conveyor feeding the pellet mill or in a special conditioning chamber with feed, is normally in capacity of 5 – 7% of the normal production of the pellet mill without steam having been added. With 3 x the capacity of the pellet mill without steam, at least 2% moisture should be added to the mix containing a minimum of 12% moisture prior to steam addition. Wet molasses addition and further water addition may be used to bring the mix to +- 12% prior to steam addition. The pelleting process would remove around 2% moisture from the mix resulting in neither shrinkage nor gain. Higher moisture addition would result in higher gain but also in more pellet breakage – thus a 2% gain is generally accepted as optimal.

9. Pellet mill: The original pellet mills manufactured and patented in 1931 in California, had a stationary flat die. Today primarily cylindrical as well as flat revolving and stationary dies are used. Smaller mills up to +- 30 kw and 1 ton capacity per hour on dry basis are often flat dies due to its relatively simpler design, faster cleaning (when blockages occur), lower die-, roller- and maintenance cost and generally lower market entrance cost. Speed reduction may be either be V-belt with sprocket and chain and gearbox. Mills are generally driven by electric motors but diesel or petrol engines with gearboxes are often fitted. Ensure the supplier has sufficient dies and rollers and other spare parts in stock and is able to service the mill, before buying it. It is strongly advised not to try and import a pellet press yourself as end user as you will probably end up re-buying this machine several times over.

10 Pellet cooler and grader: Pellets need to be cooled with cold air to avoid sweating which produces cracking and disintegration. Broken pellets are screened out and may be used to either re-introduce into the pellet press or may be crumbled for small sized feed for poultry and birds. The preferred conveyance methods are bucket elevators and belt conveyors to avoid breaking of pellets

11. Crumbler: This is a roller mill through which pellets are run crumbled to the desired size for feeding chicks of various types.

12. Finished products bins are  filled with bucket elevators and  belt conveyors and unloaded the same way into bulk feeding trucks or bagged off for further distribution.

These and many more pelleting facts can be obtained by visiting www.abchansen.co.za.

Read More

By Dr André van der Vyver, University of Pretoria

Grain storage has been a politically sensitive issue since the beginning of the 20^th century. In the early 1900s there was hardly any grain storage available in South Africa and the few facilities that existed belonged to milling companies such as Premier Milling in Newtown, Johannesburg which erected some of the first, limited facilities to store flour, imported wheat and grain purchased from local farmers. It was only in the years that followed the promulgation of the South African Marketing Act in 1937, that storage was collectively built by farmer co-operatives who, as agents, stored grain on behalf of the agricultural Control Boards that was established under the same Act.

Read More

Insta Pro^® is constantly evaluating new and existing processing technologies at our Hanson & Said Research and Development Center and testing ingredients through multiple animal feeding trials throughout the year. In 2018, a study was conducted at the University of Illinois to update information on digestibility of amino acids and energy concentrations in ExPress® soymeal with respect to hexane-extracted soybean meal fed to growing pigs. ExPress® soymeal had an advantage of +3.6% improved digestibility of essential amino acids in comparison with the hexane-extracted soybean meal.

Digestibility of all amino acids is enhanced in ExPress® soymeal versus hexane-extracted soybean meals. This includes essential amino acids as well as less recognized amino acids like valine, which can limit production in certain situations like the nursery phase.

ExPress® soymeal contains less moisture (higher dry matter) than most ingredients. Less moisture equals concentrated nutrients and more room in the diet for other ingredients. 

Results from this study demonstrate the proper use of processing temperatures during high-shear dry extrusion (which is the cooking step of the ExPress® process) as a key factor to produce a high-quality feed ingredient and consequently, better digestibility of amino acids and increased energy concentration in one ingredient for proper diet formulations.

Furthermore, pigs not only need amino acids but also energy for normal activities, such as growth and meat production. In the same feeding trial it was shown that ExPress® soymeal has +609 kg/DM of metabolizable energy concentration in comparison to solvent-extracted soymeal which means more energy is available to be used by pigs for productive purposes.

This advantage is due to the nutritional value of ExPress® soymeal, which has more residual oil in the meal when compared to the solvent-extracted soymeal. More residual oil in the meal means no need to add fats or oils of questionable quality to swine diets to provide energy. Knowing the values of metabolizable energy and digestible amino acids of ExPress® soymeal allows more precise diet formulation to assure an adequate balance of amino acids and energy in pig diets.

As usual, the ABC Hansen with its Hippo Mills and Scanwood Solution division again has something special to offer our customers at Nampo.

This year our focus is on animal feed production through different routes. Our Danish sister company Cormall has, for many years focussed in straw, hay and silage processing mainly to the biomass energy market but also to the dairy and beef cattle sector. It’s very large spiral mixers in capacities 18m3, 22m3, 30m3, 42m3 and 50 m3 has been the cornerstone of its processing system and we have brought these magnificent mixers to Nampo this year.

The MX30 mixer can handle some 7.5 tons of straw, hay and a higher tonnage of silage in one mix and at 8-15 mixes per 8 hour day, some 60 – 120 tons can be processed in one day. The most remarkable feature however is the low power consumption of only 44kW on the 50 cubic meter mixer versus at least 240 kW on a similar vertical mixer, or just 18% of the vertical mixer’s power. And the high efficiency difference is obvious when considering the following comparative ratios:

1. Feed variation 16.1% in Cormall vs 41.9% in vertical mixers.
2. Mix variation 3.7% vs 9.4% in the verticals.
3. Mineral variation 2.4% in Cormall mixers vs 9.4% in vertical mixers.

The mixer is filled with front end loaders. Bales are added without shredding and the mixed product is overhead discharged on completion in bulk trailers with unload capacity and small tractor driven.

Poultry, swine and other feeds can be mixed with the same efficiency and is easily loaded without additional conveyors into bulk cars.

Hippo Mills exhibits its HayKing hammer mill with matching HayKing hammer mill and paddles mixer in 3,000liter capacity. The landmark silo at the site this year caters for a Fine Milling Accessories and Equipment exhibition inside, well worth having a look and picking up some bargains.

Scanwood will focus on chippers – with an amazingly low priced mobile chipper being a Grizzly 180 chipper converted in-house with petrol engine drive, displaying applied local technology saving our customers thousands with the same prime equipment they are used to. Bushgraze technology will also feature prominently with systems whereby drought stricken farmers can benefit greatly.

ABC Hansen Grain is still our main feature with the 750 ton silo on site, the 100 ton per hour grain pump and the new tractor driven 200 – 240 ton per hour bunker unloader on display.

Visit ABC Hansen and Scanwood Solutions at stands numbers C34A and C3. Looking forward to farm with you.