Spent Grain: A Functional Ingredient for Food Applications

Abstract

Spent grain is the solid fraction remaining after wort removal. It is nutritionally rich, composed of fibers—mainly hemicellulose, cellulose, and lignin—proteins, lipids, vitamins, and minerals, and must be managed properly. Spent grain is a by-product with high moisture, high protein and high fiber content and is susceptible to microbial contamination; thus, a suitable, cost-effective, and environmentally friendly valorization method of processing it is required. This by-product is used as a raw material in the production of many other food products—bakery products, pasta, cookies, muffins, wafers, snacks, yogurt or plant-based yogurt alternatives, Frankfurter sausages or fruit beverages—due to its nutritional values. The circular economy is built on waste reduction and the reuse of by-products, which find opportunities in the regeneration and recycling of waste materials and energy that become inputs in other processes and food products. Waste disposal in the food industry has become a major issue in recent years when attempting to maintain hygiene standards and avoid soil, air and water contamination. Fortifying food products with spent grain follows the precepts of the circular bio-economy and industrial symbiosis of strengthening sustainable development. The purpose of this review is to update information on the addition of spent grain to various foods and the influence of spent grain on these foods.

Exploiting Agri-Food Waste as Feed for Tenebrio molitor Larvae Rearing: A Review

“…Spent grains, apart from being available all year, constitute an economic by-product. Also, spent grains are a nutritious by-product as they are rich in fiber, protein, and minerals [107][108][109]. Presumably for the above reasons, Mancini et al [110] decided to implement these sub-products for the rearing of TM larvae and to test the effect on their nutritional value.…”

Toward Circular Economy: Potentials of Spent Coffee Grounds in Bioproducts and Chemical Production

“…SCGs typically contains approximately 37% mannose, 32% galactose and 7% arabinose [18]. When compared to other biomasses such as spent brewer grains that also contain hemicelluloses, SCGs possess a higher content of mannose and no xylose content, while BSG levels contain xylose and arabinose, but no mannose [25]. The presence of arabinoxylans in SCGs adds complexity to the matrix, influencing their texture and overall properties [26].…”

Microbial Fermentation of the Water-Soluble Fraction of Brewers’ Spent Grain for the Production of High-Value Fatty Acids

“…Overall, the valorization of BSG from a circular economy perspective contributes to reduce both the carbon footprint and disposal costs associated with brewing processes. Consequently, the number of scientific studies investigating BSG as a low-cost, renewable feedstock for the development of new processes has increased exponentially [3][4][5][6][7][8][9][10][11][12][13].…”

“…makes this material suitable for various applications, including as an ingredient in fu tional foods for human nutrition. These aspects suggest the potential of BSG as a sourc compounds to be used for the preparation of different products of commercial relevanc Overall, the valorization of BSG from a circular economy perspective contribute reduce both the carbon footprint and disposal costs associated with brewing proces Consequently, the number of scientific studies investigating BSG as a low-cost, renew feedstock for the development of new processes has increased exponentially [3][4][5][6][7][8][9][10][11][12][13].…”

“…Saturated fatty acids, with the percentage of the most relevant components of the mixture in brackets 4. Mono-unsaturated fatty acids, with the percentage of the most relevant components of the mixture in brackets 5. Polyunsaturated fatty acids, with the percentage of the most relevant components of the mixture in brackets: linoleic acid (LA), γ-linolenic acid (GLA), α-linolenic acid (ALA), arachidonic acid (ARA) and cis-5,8,11,14,17-eicosapentaenoic (EPA).…”