No abstract

Interference of lactose and sucrose in refrigerated storage of firm consistency yogurtsInterferência da lactose e sacarose no armazenamento refrigerado de iogurtes de consistência firme

Due to the large number of people with lactose maldigestion, the dairy industries have increased production and diversity of low lactose and lactose-free foods. Consequently, the need to control the lactose hydrolysis process has also risen. This study aimed to correlate freezing point depression (cryoscopy) and lactose concentration, quantified by high-performance liquid chromatography (HPLC), in UHT milk. To accomplish this, UHT milk samples were subjected to seven lactose hydrolysis treatments, using lactase enzyme, resulting in different lactose concentrations. All samples were subjected to HPLC analysis and freezing point measurement, using a cryoscope. The results were plotted on a graph and a linear regression was performed. There was a strong correlation between lactose concentration and freezing point (R = 0,9973) and the coefficient of determination (R2) was 0,9946, which means that 99,46% of the variability of the response data is explained by the linear regression model. Therefore, the results point to the feasibility of estimating the lactose concentration in milk during the hydrolysis process for the production of low lactose milk, by cryoscopy, a quick analysis, with lower cost compared to HPLC and that is already among the analyses commonly performed in dairy industries.

Microencapsulation of biological control agents by spray drying (SD) has been studied as a method for increasing product shelf life and stability to enable the application of microencapsulated agents in sustainable agriculture. In this study, the microencapsulation of Trichoderma asperellum conidia by spray drying was evaluated. The objective was to assess the influence of drying air temperature and wall material (maltodextrin DE20, MD20) concentration on the microencapsulation of Trichoderma asperellum conidia and to identify the optimum conditions to produce. Microparticles were characterized in terms of morphology, particle size, and shelf life. A central composite rotatable design (CCRD) was used to investigate the effect of operating parameters on drying yield (DY), moisture content, conidial viability (CV), and percentage of conidial survival (SP).Microencapsulation experiments were carried out under optimum conditions to validate the obtained model. The optimum temperature and MD20/conidia dry weight ratio were 80°C and 1:4.5, respectively, which afforded a drying yield of 63.85 ± 0.86%, a moisture content of 4.92 ± 0.07%, a conidial viability of 87.10 ± 1.16%, and a conidial survival of 85.78 ± 2.88%. Microencapsulation by spray drying using MD20 as wall material extended the viability of conidia stored at 29°C compared with the control.

Microencapsulation of biological control agents by spray drying (SD) has been studied as a method for increasing product shelf life and stability to enable the application of microencapsulated agents in sustainable agriculture. In this study, the microencapsulation of Trichoderma asperellum conidia by spray drying was evaluated. The objective was to assess the influence of drying air temperature and wall material (maltodextrin DE20, MD20) concentration on the microencapsulation of Trichoderma asperellum conidia and to identify the optimum conditions to produce. Microparticles were characterized in terms of morphology, particle size, and shelf life. A central composite rotatable design (CCRD) was used to investigate the effect of operating parameters on drying yield (DY), moisture content, conidial viability (CV), and percentage of conidial survival (SP). Microencapsulation experiments were carried out under optimum conditions to validate the obtained model. The optimum temperature and MD20/conidia dry weight ratio were 80°C and 1:4.5, respectively, which afforded a drying yield of 63.85 ± 0.86%, a moisture content of 4.92 ± 0.07%, a conidial viability of 87.10 ± 1.16%, and a conidial survival of 85.78 ± 2.88%. Microencapsulation by spray drying using MD20 as wall material extended the viability of conidia stored at 29°C compared with the control.