Produção e caracterização de produtos lácteos em pó de búfala com e sem hidrólise da lactose

Abstract

Buffalo milk is the second most consumed milk in the world, second only to cow's milk. It presents a very differentiated physical-chemical composition, which allows a better industrial performance in the production of derivatives. Although a large part of dairy production is converted into dairy products, buffalo powdered dairy products are poorly produced in the world today, thus generating few studies on the physical-chemical and microstructural characteristics of the powdered product. Thus, the objective of this work consists of the manufacture of buffalo milk powder products with and without lactose hydrolysis, in addition to studying how different storage conditions can interfere in several characteristics that are considered fundamental for a good product. Physicalchemical analyzes were carried out on the products after their production (water activity, moisture, free and total fat, sugar concentration), in order to understand the characteristics of the products formed. It was also studied how the temperature variation, in two different storage conditions (21 ° C and 50 ° C), could modify characteristics such as the rehydration of the powder, its color and its morphology. In addition, it was studied how the storage of the product in different relative humidity of the air (11.1%; 33.1%; 43.2%; 54.4%; 75.5%) could favor the crystallization of lactose through sorption isotherm, Raman spectroscopy and chemometry techniques. With the product characterization analyzes, it was possible to notice that the products present good results of water activity (0.1705; 0.1672; 0.1737 for T1, T2 and T3 respectively) and that the product that underwent lactose hydrolysis presented a higher humidity value of 4.52, while T1 presented 3.30 and T3 3.88. The treatment that underwent lactose hydrolysis and was added with maltodextrin, showed a lower concentration of fat (22.92%), and the traditional product showed a higher result of free fat (5.67%). It is also worth noting that lactose hydrolysis was around 98% in the two treatments that suffered the breakdown of this sugar. The treatment without lactose hydrolysis showed better color and rehydration results, compared to products that underwent lactose hydrolysis, followed by the hydrolyzate product that underwent the addition of maltodextrin. The results of products stored in storage conditions that suffered temperature variation, showed that products stored at 50 ° C showed greater color advancement, a fact that contributed to the results obtained in the analysis of free HMF, colorimetry and darkening index, in addition to presenting a worse rehydration capacity as observed by particle size analysis, when compared to products stored at a temperature of 21 ° C. It is also worth mentioning that the powder morphology did not change due to the temperature variation during storage. Analyzing the group that was stored in different relative humidity of the air, it is possible to conclude that the higher the humidity of the environment, the more easily the lactose crystallizes in the product, a fact confirmed by the techniques used of sorption isotherm and Raman spectroscopy accompanied by chemometric.