Instituto de Investigación de La Cadena Láctea (CONICET-INTA), 2300, Rafaela, Argentina.
Appl Microbiol Biotechnol. 2024 May 31;108(1):354. doi: 10.1007/s00253-024-13117-2.
Whey is a byproduct of dairy industries, the aqueous portion which separates from cheese during the coagulation of milk. It represents approximately 85-95% of milk's volume and retains much of its nutrients, including functional proteins and peptides, lipids, lactose, minerals, and vitamins. Due to its composition, mainly proteins and lactose, it can be considered a raw material for value-added products. Whey-derived products are often used to supplement food, as they have shown several physiological effects on the body. Whey protein hydrolysates are reported to have different activities, including antihypertensive, antioxidant, antithrombotic, opioid, antimicrobial, cytomodulatory, and immuno-modulatory. On the other hand, galactooligosaccharides obtained from lactose can be used as prebiotic for beneficial microorganisms for the human gastrointestinal tract. All these compounds can be obtained through physicochemical, microbial, or enzymatic treatments. Particularly, enzymatic processes have the advantage of being highly selective, more stable than chemical transformations, and less polluting, making that the global enzyme market grow at accelerated rates. The sources and different products associated with the most used enzymes are particularly highlighted in this review. Moreover, we discuss metagenomics as a tool to identify novel proteolytic enzymes, from both cultivable and uncultivable microorganisms, which are expected to have new interesting activities. Finally enzymes for the transformation of whey sugar are reviewed. In this sense, carbozymes with ß-galactosidase activity are capable of lactose hydrolysis, to obtain free monomers, and transgalactosylation for prebiotics production. KEY POINTS: • Whey can be used to obtain value-added products efficiently through enzymatic treatments • Proteases transform whey proteins into biopeptides with physiological activities • Lactose can be transformed into prebiotic compounds using ß-galactosidases.
乳清是乳制品工业的副产物，是牛奶凝固过程中从奶酪中分离出来的水相部分。它约占牛奶体积的 85-95%，保留了许多营养成分，包括功能性蛋白质和肽、脂肪、乳糖、矿物质和维生素。由于其组成主要是蛋白质和乳糖，因此可以被视为增值产品的原材料。乳清衍生产品常用于补充食品，因为它们对人体有多种生理作用。乳清蛋白水解物被报道具有不同的活性，包括降压、抗氧化、抗血栓、阿片样、抗菌、细胞调节和免疫调节。另一方面，从乳糖中获得的半乳糖低聚糖可用作对人类胃肠道有益微生物的益生元。所有这些化合物都可以通过物理化学、微生物或酶处理获得。特别是，酶处理具有高度选择性、比化学转化更稳定、污染更少的优势，这使得全球酶市场以加速的速度增长。本文特别强调了与最常用酶相关的来源和不同产品。此外，我们讨论了宏基因组学作为一种工具，用于从可培养和不可培养的微生物中鉴定新的蛋白水解酶，这些酶预计具有新的有趣的活性。最后，我们综述了用于转化乳清糖的酶。在这种情况下，具有β-半乳糖苷酶活性的碳水化合物酶能够水解乳糖，获得游离单体，并进行转半乳糖基化以生产益生元。要点：• 通过酶处理可以有效地从乳清中获得增值产品。• 蛋白酶将乳清蛋白转化为具有生理活性的生物肽。• β-半乳糖苷酶可将乳糖转化为益生元化合物。
