121 Use of Fermentation Co-products in Pet Food and Animal Feeds

Fermentation is used to create foods and beverages that are enjoyed by people around the world. Similarly, fermentation creates direct opportunities for feed application such as fermented liquid feed or fermented feedstuffs. Other opportunities exist: fermentation followed by extraction of a main product for human or biofuel application also creates co-products that require application in petfood or animal feeds for valorization. Indeed, cereal grains are fermented to produce beer, distilled spirits, or bioethanol and their associated co-products can be fed either wet or dry. For example, traditional beer production using fermentation of barley grain produces abundant brewer’s spent grains and also brewer’s spent hops and yeast as co-products. Brewer’s spent grains are mostly fed wet to ruminants due to its greater fiber content than barley grain and avoiding the cost of its drying required for compound feed application. Wet brewer’s yeast can be used as feedstuff in liquid feed systems for swine. Dried brewer’s yeast can be considered for pet food application due to included nutrients, nucleotides, mannan oligosaccharides, and β-glucans. Other cereal grains such as corn and rice are also used for beer production. Whiskey is produced using fermentation of an array of cereal grains, and distiller’s co-products have traditionally been fed wet or dry mostly to cattle. For the last two decades, large-scale production of ethanol as biofuel has created the co-product distillers dried grains with solubles (DDGS) as commodity feedstuff. Subsequently, DDGS has been used in livestock feed and petfood as protein source. With animal feed application, dietary inclusion of fermentation co-products provides opportunities for circular agriculture whereby nutrients excreted by livestock will be applied to soil to support grain production. Finally, depending on price and quality, fermentation co-products may be part of pet food and livestock feed formulations to achieve competitive cost and functionality.