The effect of probiotic crops and lipolytic enzymes on the properties of dairy products in the cheese biotechnology under development

This article aims to evaluate the influence of probiotic microorganisms and pregastric lipase on organoleptic and biochemical characteristics of soft cheese made from a mixture of milk and buttermilk. The study was designed to determine how the temperature and exposure at this temperature affect the growth and development of lactose and bifidobacteria, as well as their quantity in the finished product. In order to increase the biological and nutritional value of the developed soft cheese, protein-carbohydrate raw materials rich in vitamins A, B12, D, E, phosphate and minerals were introduced into the production mixture. The addition of buttermilk increased the biological value of the product and improved its consistency. The taste and consistency of cheese was improved by a pregastric lipase preparation, widely used in the cheesemaking industry for production of various cheeses with high and low temperatures of the second heating. As a result of directed lipolysis, the finished product accumulates free fatty acids and diacylglycerols, acting as plasticizers and affecting the texture and organoleptic characteristics of the cheese. The results show that combining buttermilk and milk in an optimal ratio and addition of lipase produce a product with the best physicochemical parameters and a maximum evaluation of organoleptic characteristics. In the presence of a probiotic starter culture (provided there is a ready-made substrate), an active synthesis of enzymes necessary for the complete hydrolysis of milk fat begins. This all creates a functional product.

Changes in lipid fractions and sensory properties of Idiazabal cheese induced by lipase addition

This work studied the addition of an adequate lipase to enhance lipolysis reactions and the development of piquant flavour and sharp odour in Idiazabal cheese, as an alternative to the use of lamb rennet paste. Cheeses were manufactured from bulk raw ewes' milk in 50 l vats with commercial bovine rennet and 80 lipase units of pregastric or 180 lipase units of fungal lipase and ripened for 180 days. A higher lipolytic activity was induced by lipase addition promoting strong changes in odour and flavour attributes. Both fungal and pregastric lipases increased the content of total free fatty acids (FFA), but the fungal lipase released mainly medium- and long-chain FFA. In contrast, the pregastric lipase preferably released short-chain FFA. Diglyceride (DG) content was considerably higher in cheeses made with added pregastric lipase compared with those made with fungal lipase or with no lipase. Monoglycerides (MG) were detected only in cheeses made with either lipase added, reaching comparable concentrations after ripening for 180 days. The cheeses made with pregastric lipase had the highest scores for odour and flavour intensity, and sharp and rennet odours, desirable attributes for the Idiazabal cheese made with lamb rennet paste. None of the texture attributes were significantly influenced by the concentrations of MG and DG in the cheeses made with either lipase. Thus, the pregastric lipase was more appropriate than the fungal lipase to develop a more traditionally-flavoured Idiazabal cheese.