Application, characterisation and economic assessment of brewers’ spent grain and liquor

Abstract

New value-adding applications of spent grain, a co-product of brewhouse operations, are considered in the context of a sustainable circular economy. Previous studies have focused on the compounds remaining in the solid phase of the spent grain. However, depending on the dewatering process, the separated water also contains relevant fractions of nutritionally and physiologically valuable compounds including proteins, carbohydrates and polyphenols. Accordingly, the work reported here considers the two fractions and presents a detailed view of relevant substances especially those from liquor. The reported mass balance is the result of these investigations, supplemented by values from the literature. The potential value of these compounds for industrial biotechnology is examined in an economic assessment. © 2022 The Authors. Journal of the Institute of Brewing published by John Wiley & Sons Ltd on behalf of The Institute of Brewing & Distilling.