Functional, industrial and therapeutic applications of dairy waste materials

Dairy waste management to reduce environmental pollution through its utilization in various food and non-food products is a major concern of the dairy industry. Whey and buttermilk are regarded as the major waste materials of the dairy industry. Therefore, the current review aimed to summarize the various extraction methods and potential application of buttermilk and cheese whey in production of different products, i.e., microencapsulation matrix, beverages, baked products, microorganisms' cultivation, edible films, exopolysaccharides, organic acids, and essential fatty acids. These wasted components can be extracted from the dairy products by utilizing various extraction methods such as conventional homogenization, ultra-high-pressure homogenization, ultrafiltration, reverse osmosis, and nanofiltration. In microencapsulation technology, these have been used to encapsulate various essential oils, probiotics and several bioactive substances. Whey and buttermilk-based beverages have also been prepared to accentuate their application in the beverage industry. Whey and buttermilk-based microbial fermented products have a significant role in value-added food production. Edible coatings prepared from whey protein concentrate are more accessible, environmentally friendly, nontoxic, and low cost. In addition, several bioactive substances such as exopolysaccharides, bioactive peptides, essential fatty acids, and organic acids have been extracted from the whey and buttermilk. Moreover, these have the potential to improve the physicochemical, organoleptic, and rheological properties (i.e. water absorption, gelatinization temperature, dough development time) of baked goods in the bakery industry. In conclusion, utilization of dairy waste materials in various products can be proved beneficial in introducing various dairy-based healthy products, reduction of environmental pollution and economic growth of the country.