Characterization of Brewers' Spent Grains (Major Brewery Waste) From Local Breweries Around Columbus, Ohio in the United States

ABSTRACT Brewers' spent grains (BSG), a major byproduct of the brewing industry, accounts for 85% of its total waste. Due to its high initial moisture content, BSG has a limited shelf life. However, once dried, BSG contains around 60% dietary fibers and 20% protein making them a promising high fiber and high‐protein ingredient to be incorporated in foods. Numerous studies have explored the potential use of BSG in food applications, where knowledge of their proximate composition becomes essential for product formulations development. Notably, the composition of BSG from local or craft breweries differs significantly from that of large scale national brands. Thus, this study was conducted to characterize the composition of BSG from 24 local breweries in the Columbus, Ohio area. Using approved standardized methods, moisture, ash, lipids, proteins, and carbohydrates contents were measured. While moisture and ash contents showed minimal variation, noticeable substantial differences were measured in the levels of carbohydrates (65%–70%), protein (18%–24%), and lipids (8%–14%). The variation is primarily attributed to changes in brewing practices and in ingredients used to produce beer styles unique to each brewery. The information about the composition of BSG from local breweries can be extremely useful for its potential application in food products. Instrument‐based techniques (like near infrared [NIR] or mid infrared [MIR] spectrometers) can be developed based on wet chemistry methods that can offer rapid and precise estimation of BSG composition for the future use. Such an approach will eliminate or greatly reduce the waste generated from the breweries.