The 36.4 million tons of brewers’ spent grain produced annually yield a potential feed stream for animal agriculture.
But unlike hogs and cattle, chickens cannot digest the fiber-rich ingredients.
A team of researchers at Cornell University set out to change this by finding a way to optimize the spent grain.
Elad Tako, corresponding author and associate professor in the department of food science, and doctoral student Melissa Huang, who helped lead the research, answered some questions about the project and brewers’ spent grain as a future chicken feed.
Their answers below are edited only for grammar and AP style specifications.
Summarize the research findings as to whether broilers can digest any part of brewers’ spent grain and, if so, which parts.
“Our work focused on a water-based extract of brewers’ spent grain and its impact on the broiler chicken gut. The reason we isolated an extract is based on previous reported issues with digestibility of the whole byproduct and that our chicken model (in ovo/intra amniotic administration method) necessitates a liquid sample.
“We employed a green, simple extraction technique and recovered polymeric tannins. Thus, our study does not speak to the digestibility of whole brewers’ spent grain but instead explores the benefits of a water-soluble fraction.
“We observed an improvement in small intestine tissue development as well as changes in the gut microbiome that point to potential benefits for broilers consuming brewers’ spent grain-derived compounds.”
What additional testing needs to be done on this topic?
“There are several interesting and necessary future studies to follow the current. One would be testing the same brewers’ spent grain extract at different doses in a long-term feeding trial. This would give us a true understanding of the functionality and health impact for farmers looking to include this upcycled material.
“Another could be comparing whole brewers’ spent grain and the current extract.
“Finally, depending on these studies, it would be interesting to assess whether the bioactivity of brewers’ spent grain compares to the recently banned antibiotic growth promoters in a long-term feeding trial.”
What percent of a chicken’s feed could be replaced by these spent grains?
“Since we are testing a brewers’ spent grain extract, we are not able to speak to the impact of brewers’ spent grain solids on broiler health.
“With that being said, previous studies suggest that 20% is the upper limit of feed inclusion before whole brewers’ spent grains start to negatively affect the bird’s health.
“A long-term study, like the ones described above, would provide the necessary data to answer this question.”
What are the benefits of feeding this spent grain? These could be economical, environmental or developmental for the birds.
“The benefit of feeding spent grain falls in all three of these categories.
“Since we saw positive changes in tissue development and the microbiota, we could propose a gut health benefit of brewers’ spent grain.
“Utilizing this byproduct of beer processing reduces waste accumulation in landfill and its downstream environmental effects.
“Finally, less waste for beer processors means less money devoted to removing waste from their plants. In addition, defining the value of the spent grains can be capitalized upon.”
What would the process be — both in terms of legislation and infrastructure — to make spent grains part of commercial chickens’ diets?
“Depending on the desired form of spent grain for poultry feed (whole, extract, etc.), processing plants would need to be furnished accordingly.
“Beer producers would need to implement storage infrastructure for the spent grain since its high moisture is a breeding ground for pathogenic and spoilage microorganisms.
“In terms of legislation, the FDA has recently included current good manufacturing practices as a part of the Food Safety Modernization Act for byproducts utilized in animal feed.”
How is the grape pomace as chicken feed study going?
“We have completed our first study looking into a Concord grape pomace sample and its anti-inflammatory effects (in review).
“We have just started a follow-up study with several different grape-derived products (skin, seed, pomace, phenolic extracts, etc.) to help determine what specific compounds in grape waste streams could be contributing to the observed bioactivity.
Is there anything else you would like to add?
“With the rise in poultry products consumption (meat and egg), the upcycling of spent grains (current industry by product) as a sustainable and bioactive dietary ingredient in poultry feed has great promise, and we are dedicated to continue and investigate this opportunity.”
Source: Lancaster Farming
