Institut National de la Recherche Scientifique, Centre-Eau Terre Environnement, 490, Rue de la Couronne, Québec City, QC G1K 9A9, Canada.
Département de Génie Chimique et de Génie Biotechnologique, Faculté de Génie, Université de Sherbrooke, 2500 Boulevard de l'Université, Sherbrooke, QC J1K 2R1, Canada.
Molecules. 2023 Jul 20;28(14):5536. doi: 10.3390/molecules28145536.
Whey is a dairy residue generated during the production of cheese and yogurt. Whey contains mainly lactose and proteins, contributing to its high chemical oxygen demand (COD). Current environmental regulations request proper whey disposal to avoid environmental pollution. Whey components can be transformed by yeast into ethanol and biomolecules with aroma and flavor properties, for example, 2-phenyethanol (2PE), highly appreciated in the industry due to its organoleptic and biocidal properties. The present study aimed to valorize agri-food residues in 2PE by developing suitable bioprocess. Cheese whey was used as substrate source, whereas crab headshells, residual soy cake, and brewer's spent yeast (BSY) were used as renewable nitrogen sources for the yeasts and . The BSYs promoted the growth of both yeasts and the production of 2PE in flask fermentation. The bioprocess scale-up to 2 L bioreactor allowed for obtaining a 2PE productivity of 0.04 g/L·h, twofold better productivity results compared to the literature. The bioprocess can save a treatment unit because the whey COD decreased under the detection limit of the analytical method, which is lower than environmental requirements. In this way, the bioprocess prevents environmental contamination and contributes to the circular economy of the dairy industry.
乳清是奶酪和酸奶生产过程中产生的乳制品副产物。乳清主要含有乳糖和蛋白质，这导致其化学需氧量（COD）很高。当前的环境法规要求妥善处理乳清，以避免环境污染。酵母可以将乳清中的成分转化为乙醇和具有香气和风味特性的生物分子，例如 2-苯乙醇（2PE），由于其感官和杀菌特性，在工业界受到高度赞赏。本研究旨在通过开发合适的生物工艺来利用农业食品副产物生产 2PE。使用奶酪乳清作为底物来源，而蟹头壳、剩余的大豆饼和酿酒废酵母（BSY）则被用作酵母和的可再生氮源。BSY 促进了两种酵母的生长和 2PE 在摇瓶发酵中的生产。生物工艺放大到 2 L 生物反应器，可获得 0.04 g/L·h 的 2PE 生产率，比文献报道的生产率提高了一倍。该生物工艺可以节省一个处理单元，因为乳清 COD 降低到分析方法的检测限以下，低于环境要求。这样，该生物工艺可以防止环境污染，并有助于乳品行业的循环经济。
