Cervantes-Ramirez Joel G, Vasquez-Lara Francisco, Sanchez-Estrada Alberto, Troncoso-Rojas Rosalba, Heredia-Olea Erick, Islas-Rubio Alma R
Coordinación de Tecnología de Alimentos de Origen Vegetal, Centro de Investigación en Alimentación y Desarrollo, A.C., Carretera Gustavo E. Astiazarán Rosas # 46, Colonia La Victoria, Hermosillo 83304, Mexico.
Centro de Biotecnología FEMSA, Instituto Tecnológico y de Estudios Superiores de Monterrey, Ave. Eugenio Garza Sada No. 2501, Monterrey 64849, Mexico.
Foods. 2022 May 13;11(10):1415. doi: 10.3390/foods11101415.
Brewers' spent grain (BSG) is the most abundant byproduct generated from the beer-brewing process. BSG is a material rich in hemicellulose, composed of arabinoxylans (AX). However, the high crosslinking of this material causes low availability of AX, for which it is necessary to apply different treatments. The objective of this research is to increase the release of arabinoxylans through solid-state fermentation with f. sp. using extruded brewery spent grain. First, the BSG is subjected to two types of physical treatments: extrusion at 20% moisture, 200 rpm and 50 °C (BSGe), and blade milling (BSGm). The chemical composition is determined for each sample (BSG, BSGe and BSGm). Subsequently, the solid-state fermentation process (SSF) is carried out on each sample. The fermentation kinetics at 30 °C are monitored for 7 days. Once the SSF concludes, AX are extracted, and the purity of AX is determined by the phloroglucinol colorimetric assay. Finally, the total phenolic compounds, phenolic acids and antioxidant capacity by DPPH are quantified. No significant differences ( ≥ 0.05) in the protein, lipid, ash or total dietary fiber contents are found among the samples. No significant difference ( ≥ 0.05) in the content of soluble fiber is found, although BSGe and BSGm have higher values than BSG. On the other hand, the yields of soluble AX exhibit significant differences ( ≤ 0.05) among nonfermented samples (BSG, 0.03%; BSGm, 0.53%; BSGe, 0.70%) and with SSF (BSG, 2.95%; BSGm, 6.24%; and BSGe, 9.58%). In addition, the contents of free phenolic compounds and free phenolic acids and the percent inhibition of free extracts by 2,2-diphenyl-1-picrylhydrazyl (DPPH) differ significantly ( ≤ 0.05) between samples subjected to SSF and nonfermented samples. Therefore, extrusion and SSF treatment increase AX release from BSG as well as the antioxidant capacity of the extracts.
啤酒糟是啤酒酿造过程中产生的最丰富的副产品。啤酒糟是一种富含半纤维素的物质，由阿拉伯木聚糖（AX）组成。然而，这种物质的高度交联导致AX的利用率较低，因此有必要采用不同的处理方法。本研究的目的是通过使用f. sp.对挤压后的啤酒糟进行固态发酵，增加阿拉伯木聚糖的释放量。首先，对啤酒糟进行两种物理处理：在20%湿度、200转/分钟和50°C条件下挤压（BSGe），以及刀片粉碎（BSGm）。测定每个样品（啤酒糟、BSGe和BSGm）的化学成分。随后，对每个样品进行固态发酵过程（SSF）。在30°C下监测发酵动力学7天。固态发酵结束后，提取AX，并通过间苯三酚比色法测定AX的纯度。最后，对总酚类化合物、酚酸和DPPH抗氧化能力进行定量。样品之间在蛋白质、脂质、灰分或总膳食纤维含量方面未发现显著差异（≥0.05）。在可溶性纤维含量方面未发现显著差异（≥0.05），尽管BSGe和BSGm的值高于啤酒糟。另一方面，未发酵样品（啤酒糟，0.03%；BSGm，0.53%；BSGe，0.70%）与经过固态发酵的样品（啤酒糟，2.95%；BSGm，6.24%；BSGe，9.58%）之间可溶性AX的产量存在显著差异（≤0.05）。此外，经过固态发酵的样品与未发酵样品之间，游离酚类化合物和游离酚酸的含量以及2,2-二苯基-1-苦基肼（DPPH）对游离提取物的抑制百分比存在显著差异（≤0.05）。因此，挤压和固态发酵处理增加了啤酒糟中AX的释放量以及提取物的抗氧化能力。
