Incorporation of Fermented Brewers Spent Grain in the Production of Sourdough Bread

Frank Vriesekoop,Hao Liang,Niels Van Der Heijden,Antien Zuidberg,Annie Haynes,Paraskevi Paximada

doi:10.3390/fermentation7020096

Abstract

The utilisation of food production by-products back into food production within a circular food economy is one of the driving examples to improve sustainability within the food industry. Brewers spent grain is the most abundant by-product from the brewing industry, with currently most of it being used as animal feed. In this study, we utilised brewers spent grain as a substrate in a solid-state fermentation in order to produce a Type-3 sourdough culture. Sourdough bread is becoming increasingly popular throughout the western world. The use of fermented brewers spent grain in the production of sourdough bread yielded sourdough bread that was acceptable by consumers. We also investigated the production and presence of the main organic acids in sourdough during the proofing process and the baking process. The baking trials showed that there was a reduction in both lactic and acetic acid content during the actual baking process. The reduction in the concentration of both organic acids appears to be at the heart of the observation that for both organic acids, there is typically a lower concentration in the crust compared to the crumb of the sourdough breads, which was observed in our sourdough breads and those commercially available.

Highlights

IntroductionThe brewing industry in the United Kingdom (UK) produces approximately 0.5 million tons of brewers spent grains (BSG) annually as a by-product of beer production, which equates to 85% of the produced by-products [1,2]
Following the completion of the solid-state fermentation (SSF), the fermented BSG (FBSG) was dried at 60 ◦ C to aid in the preservation of the fermented spent grain while at the same time retaining a viable sourdough culture on the dried grains
The FBSG was used used in a series of experimental trials,which during wethat showed thatacid bothand lactic in a series of experimental baking baking trials, during wewhich showed both lactic acid and acetic acid productivity were during retained dough fermentation acetic acid productivity were retained theduring doughthe fermentation

Summary

Introduction

The brewing industry in the United Kingdom (UK) produces approximately 0.5 million tons of brewers spent grains (BSG) annually as a by-product of beer production, which equates to 85% of the produced by-products [1,2]. Utilising or disposing of BSG is a serious challenge and is driven mainly by environmental and business pressures [3], and by challenging distribution channels and lack of disposal outlets [4,5,6]. Larger breweries often sell it for animal feed at low costs [7,8], whereas smaller breweries often have a wider range of outlets e.g., research, animal feed, bakeries, etc., depending on location and demand [9]

Methods

Results

Conclusion