Bulk density is an important metric in many things such as bagging or conveying. Many websites and resources feature bulk densities of known products such as whole soybeans, ground soybeans, corn, etc, but what do you do if you’re trying to determine something new? There are several times when you may have to decide on a mixer or bin capacity that will contain several different products with different bulk densities. How would you calculate this? With some simple math and some patience, you’ll be able to determine these answers.
What You Need
To start, you will need to know some existing densities of products. As mentioned, there are several resources that have a good range of known products.
As an example, let’s assume we have a formula with the following blend percentage for 1 ton (2000 lbs) of final product:
– Coarse cracked corn: 70% (1400 lbs)
– Ground soybeans: 20% (400 lbs)
– Cracked wheat: 10% (200 lbs)
From various sources, we know the following estimates:
– Coarse cracked corn bulk density: 40 lbs/cubic foot
– Ground soy bulk density: 35 lbs/cubic foot
– Cracked wheat bulk density: 45 lbs/cubic foot
How to Calculate
An easy method is to multiply the bulk density by their respective percentages, then add everything together.
– Coarse cracked corn: 70% x 40 lbs = 28 lbs
– Ground soybeans: 20% x 35 lbs = 7 lbs
– Cracked wheat: 10% x 45 lbs = 4.5 lbs
Adding these together gives an estimated bulk density for the product of 39.5 lbs/cubic foot.
You can do this for as many ingredients as you have by using the same methods described above and then adding the values together.
If you are interested in an alternative method, you can do the following:
– Take the individual weight of each ingredient,
– Determine the total volume of all ingredients, and then
– Take the total weight divided by the volume
This will give a slightly different value, but the difference is negligible. If you have any questions regarding bulk density calculations, give us a call, we’re here to help!
Animals are driven to seek and consume food energy every day – this makes it possible for normal activities, such as growing and walking, to happen. Food energy is also critical in supporting “higher-performance” activities. When athletes engage in rigorous physical activity, their energy needs increase because of the extra work being done by their muscles.
The same is true for “higher-performance” livestock animals, such as dairy cows. To allow dairy cows to produce more milk, more food energy must be supplied. Larger cows require more energy at the same performance level, simply to maintain normal functions.
When considering that food energy is the largest cost of feeding livestock, on an absolute basis, two things become obvious:
Diets should be formulated to meet, but not exceed, the energy requirement.
Extracting energy from an ingredient is imperative (considering the economics of doing the extracting, of course).
Processing is one of the best ways to liberate energy. Extruders do this very thing – allow animals to extract more energy from the same unit mass of an ingredient.
So far, this all seems fairly simple. However, consider the following:
Reducing the extrusion temperature by 50oC has been shown to reduce the energy in soybeans available to poultry by about 7%.
So, processing without quality controls is asking for variation in energy values.
Experiments with animals to determine energy data are expensive and time-consuming, and so, nutritionists will formulate diets using prediction equations or table values, which may not reflect what is happening in the animal, or what is happening with a process.
Age of the animal, stage of production, individual animal variation, environmental factors – all affect energy needs and must be considered.
It must be clear how data is expressed and used – is the moisture content of the ingredient considered (dry matter vs. as-fed basis)? How is the energy value expressed (Gross energy versus metabolizable energy)? What energy use by animals cannot be accounted for accurately, or at all, and how is this uncertainty dealt with?
An example can be seen by going back to the chart on energy requirements of dairy cattle (above), and comparing these predicted energy requirements to published data on actual energy levels in the diet and milk production (Broderick, 2003). The prediction from the chart underestimated energy requirements, from 2.2 megacalories per day (at 69 lbs. milk production per day), to 0.32 megacalories per day (at 81 lbs. milk production per day). In this case, using a prediction energy equation would have limited milk production – although keep in mind that some estimations were used to formulate the diets, too.
In conclusion, using ingredients to supply energy to animals is an art, as well as a science. In the beginning, gather as much information as you can, and then, the animals will tell you a lot once you start feeding them.
We are living in an era where imitations and copycats are fact of life. Some of us are tempted to invest in a knockoff item if we perceive that it will function just like the original, but at lower cost to us.
Most of the time, we are disappointed with either the performance of the imitation or its durability. The main objective of a copycat entity is to make the item look like the original. In most cases, not much attention is paid to the functionality or the durability of the copy.
Our business of extrusion is not an exception, we hear sad stories from some customers who invested in knockoff extruders that did not deliver the quality of product they were anticipating and reached a conclusion that they need to go back to the original to keep their business alive.
Using genuine original wear parts for an extruder to achieve the followings:
Targeted quality of the finished product
To assure safety of operation
Reduce the cost and add to the bottom line savings.
The fact that many original brand extruders and their wear parts have been copied by companies in China, the Ukraine, South Africa and other countries. These copy extruders are offered to the market with a very attractive price and as if they are one and the same as the original.
A study conducted showing the hidden cost of using imitation parts as compared with the original. The study focused on an Extruder part’s durability.
The study documented the following facts about the imitation parts relative to the original:
North American competitor wore 33% faster
African competitor wore 167% faster
Asian competitor wore 633% faster
Latin American competitor wore 900% faster
Although the cost of the imitation parts is less than the cost of the original parts, the total cost to the end user is much higher due to:
Inferior quality of extruded products
Higher capital cost of frequently replaced imitation parts
More repair and maintenance
Lack of safety assurances
What was not measured here, is the quality of extruded products and their relative value. Having an extruder is one thing and producing the quality product is another. It is typical of an original extruder manufacturer to provide on demand guidance, recommendations, service and help from their engineers, nutritionists, technicians and sales force to advance the quality and value of the extruded products.
As we shop for prices, sometimes we come up winners and most of the time we get what we pay for.
As protein ingredient options become more and more expensive, alternative ingredients are sought to control feed cost. One option has been the use of Urea as a source of non-protein nitrogen (NPN) for ruminant micro flora.
Since the early history of its utilization, it became clear that some of the short-comings of feeding urea are:
Its rapid hydrolysis into ammonia.
The physical properties of the product when used in high protein supplements.
Toxicity can be an issue if urea is not mixed well.
And the failure to adapt animals to diet slowly, especially the first few days it is fed.
To overcome those limitations, a slow release ammonia product was developed where Urea and a grain such as corn, wheat, milo or barley are extruded in a high shear, dry extrusion. The heat generated by friction in the extruder results in the grain starch gelatinization while the urea melts and is encapsulated. After extrusion, the product is cooled, cured and ground to be used as a supplemental protein for all ruminants.
There is a product that has made it possible to utilize all non-protein nitrogen as a supplementary protein in a dry form that can be handled in a conventional feed mill and in conventional forms: pellets, blocks or cubes.
The gelatinized starch serves as an energy source as it is converted into fatty acids in the rumen while the nitrogen fraction is converted to ammonia for the production of microbial protein. The microbial protein is then transported to the abomasums where it becomes amino acids and is absorbed and utilized.
Although different ratios of starch bearing material and NPN can be successfully extruded, the protein equivalent of this product is 60%. Such a product can compete with many natural sources of protein for ruminants with an economical advantage.
Nigeria’s President, Goodluck Jonathan, is upbeat about the future of food production in his country, telling his compatriots “our future is bright”. He needs to be optimistic.
Nigeria spends $4 billion each year to import wheat, $2 billion on rice, $1.3 billion on sugar, and $600 million on fish imports.
Despite this, malnutrition is rife. According to UNICEF, one in every two children in the northern regions is stunted, a sure signal of malnutrition. One in five is zinc deficient, because their diets contain so little animal protein.
President Jonathan and his Minister of Agriculture, Akin Adesina, have a plan. First, they plan to STOP doing things, for example:
Stop treating agriculture as a development project
Stop funding isolated projects without strategic focus
Stop government crowding out the private sector
In place, they want to implement an Agricultural Transformation Agenda, to:
Focus on agriculture as a business
Use the agricultural sector to create jobs, create wealth and ensure food security
Focus on value chains where Nigeria has comparative advantage
Develop strategic partnerships to stimulate investments
Attract private sector agribusinesses to set up processing plants.
Rice, cassava, sorghum, cocoa and cotton have been singled out for value chain transformation.
The Sorghum Transformation Plan targets the northern regions of Nigeria, which tend to be poorer and more malnourished than the south. Because it is drought tolerant, sorghum does well in the arid North East and North West.
This year, Nigeria will grow almost 7 million tonnes of sorghum (compared to 9 million tonnes of maize). Yields are low, around 1.25 mt/ha. Sorghum hybrids can help push up yields to 4 mt/ha, and increase farmer income from $120/hectare to over $300/ha.
So what do you do with all this sorghum? For many people in Africa, sorghum = flour (for people who cannot afford wheat flour) and beer. There is little awareness that sorghum can be extruded with soybeans to make a smooth, pleasant-tasting and highly nutritious instant porridge for children and adults. Sorghum-Soy Blend is an excellent way of delivering vitamins and minerals, too.
It’s sad that sorghum tends to be regarded as poor man’s food in Africa. Over in the U.S., research teams at University of Nebraska, Kansas State University, University of Georgia, Texas A&M University and elsewhere, are spending millions of research dollars to unlock the nutritional secrets of sorghum.
Why? Anti-oxidants, principally. High-tannin sorghums, such as those grown and consumed in Africa, are very rich in anti-oxidants. A Georgia study found that “levels of polyphenolic compounds in the high-tannin sorghum varieties ranged from 23 to 62 mg of polyphenols per gram. For comparison, blueberries contain 5 mg of polyphenolics per gram, while pomegrante juice contains 2 to 3.5 mg per gram”.
Whether sorghum will make a dent in America’s bulging waistline and diet-related disease burden remains to be seen. But over in Africa, villagers in the Sorghum Belt are surrounded by super-healthy sorghum, and probably don’t even realize how nutritious it is.
In farming and agriculture in general, there are conditions that are beyond the control of the farmer or the producer. One of these conditions is weather.
It is not uncommon to encounter unpredictable weather such as the drought that the Midwest went through. Some years we are faced with an early frost where the soybeans for example don’t get the chance to be fully matured prior to the harvest. The soybeans are termed either immature, frost damaged or green.
The market value of such beans is very low and can translate into huge profit losses to the producers.
South Dakota State University swine scientists, Dr. Bob Thaler, has conducted studies in the early 1990’s demonstrating that you can recover the value of those beans via extruding and feeding them to swine thus eliminating huge profit losses by the producer.
Below is an article Dr. Robert Thaler dealing with this subject.
He wrote, “Due to a wet spring, late plantings, and a cooler growing season, the recent frost in the northern half of the region has resulted in some frost-damaged or green soybeans. Green beans are often severely docked at the elevator because the higher levels of chlorophyll in the bean will also end up in the soybean oil and soybean meal after they are processed, which will then be discounted in the market.”
“However, research at SDSU has shown that the swine industry is an excellent market for green, immature soybeans. Finishing pigs fed extruded green soybeans grew at the same rate but were more efficient than the pigs fed mature extruded soybeans. Also, there were no differences in carcass characteristics. Raw soybeans must be heat-treated to inactivate the anti-nutritional factors in soybeans before they can be fed to pigs, and if the soybean is fully developed but just green, it has the same feeding value as mature/yellow soybeans after they are extruded. Depending on the cost of the bean at the elevator and cost of extrusion, there can be significant feed cost savings by using frost-damaged soybeans as a protein source in pig diets. One of the benefits of feeding extruded or “full-fat” soybeans is that it’s a very easy way to add fat to a diet.”
In simple terms, shearing is what occurs when two forces act upon each other in opposite directions. The simplest example of this is when you rub your hands together. The “forces” are your hands and the “shear” is the friction in between them. You will also notice this creates heat. In terms of extrusion, we can use this to our advantage.
Why is this important to extrusion?
It’s because that is how an extruder works. As ingredients go through the barrel, screws and steamlocks, they are exposed to very high shear rates which create very high temperatures. This also creates a lot of pressure. In the case of soybeans, the temperature of the final meal can be as high as 330°F with no added heat!
What can we do with this?
This shear is what allows a product like full-fat soy to be made. The picture shows the cells of a raw soybean. Each cell contains the oil of the seed. During extrusion, the shear stress and pressure are so high that it actually ruptures and breaks these walls. The result is shown in the last picture. Since there are no more cell walls, the oil mixes with the meal to create full-fat soy.
We can expand on shear and use it to our advantage to create all sorts of products with nutritional advantages. The shearing action inside of an extruder is what allows us to make products such as cereals, pet foods, animal feeds and so on. With the right advice and expertise, this opens new possibilities for nutritional benefits and production capabilities.
Recently, the amount of methane emitted from production agriculture, and in particular, ruminant animals, has been greatly discussed. Methane is a potent greenhouse gas (more so than the typically-discussed carbon dioxide) that is getting more attention within the issue of human-induced climate change. Ruminants have a microbial fermentation vat, called the rumen, and emit a lot of methane with their normal digestive functions. And, there are a lot of cows on Earth.
This is where the open mindedness comes in. Regardless of your thoughts on the validity or scale of human effects on the global climate, methane emission from cattle is clearly one thing – lost production. Methane is a loss of dietary energy that would otherwise be used for productive purposes, such as increased milk production. Strategies that increase animal production and reduce methane often go together.
For example, feeding a ration with higher digestible carbohydrates, as in grains, will reduce methane production. Beef cattle will typically experience greater rates of gain and efficiency on these diets. The trouble with this approach, especially for highly-productive lactating dairy cattle, is that acidosis of the rumen can develop, causing performance to suffer. So, other options are needed.
Increasing dietary fat will also result in reduced methane production. A higher-quality ingredient, such as extruded/pressed soy meal, enhance rumen health and milk production while adding more fat to the diet. The addition of this soy oil (fat), as residual oil in the meal, to the diet should help reduce methane. Alternatively, an excellent source of certain fatty acids, like those found in flax, would reduce methane production even further while potentially creating a product with with improved nutrient content.
Strategies for reducing waste and pollution that often don’t stay on the farm are important challenges, and should be turned into opportunities that can used to improve the productivity of your operation. Most importantly, there are changes that you can choose to make by being open minded enough to listen.