Explore the vast range of titles available.

Essential oil blends (EOBs) have been increasingly studied for their multifunctional benefits in animal nutrition and food science. This study evaluates the impact of an EOB composed of eucalyptus and peppermint oil on the physicochemical, microbiological, and sensory characteristics of dairy products—milk, cream, and colonial cheese. Forty lactating cows were assigned to two groups: control and EOB addition (3.6 mL/cow/day) on the diet. Sensory analysis showed that the addition of EOB does not significantly alter milk or cream characteristics but enhances cheese texture perception. Fatty acid analysis revealed a higher proportion of SFA and lower UFA in cheese produced from the EOB group. Additionally, the EOB reduced lipid oxidation throughout the ripening process, with significantly lower TBARS values at 45 days of maturation (0.1300), compared to those from cows without supplementation of EOB (0.1585), suggesting improved oxidative stability. Microbiome analysis indicated that the bacterial community composition remained stable, with a slight reduction in Streptococcus spp. in EOB cheeses. No drastic shifts in microbial diversity were detected, and a lower overall abundance of bacterial taxa was observed in the EOB group. Results suggest that EOBs in dairy cow diets may positively modulate dairy product characteristics and alter the microbiota without compromising sensory quality. This study highlights the technological potential of EOB supplementation in dairy production.

The objective of this study was to evaluate yeast (Saccharomyces cerevisiae) from beer fermentation in its natural form (NY) and subjected to different processes of cellular ruptured [mechanical method using ultrasound (MRY) and modified autolysis using NaCl and ethanol (MAY)] regarding functional and digestibility properties, comparing them with textured soy protein (TSP). Ultrasound treatment resulted in 42% disruption efficiency and the micrographs obtained from scanning electron microscopy analysis showed important morphological modifications due to processes of cellular ruptured action. MRY cells presented more pronounced damage than LN, which suggests the rupture of the cell wall and exit of the internal material to the medium. NY, MRY, MAY, and TSP presented a very close composition concerning the protein content, ranging from 39.32 to 43.80% and moisture of 0.07–0.14%. In vitro digestibility of brewing yeast samples equated the digestibility of TSP (higher than 94%). Cellular disruption with ultrasound (MRY) caused an increase in foaming ability, stability and also oil retention capacity (8.82 mL of oil/g of protein). Modified autolysis (MAY) resulted in higher water holding capacity (14.50 g of water/g of protein) and index of water solubility (greater than 64%) with a decrease in their emulsifying properties. The highest water absorption capacity was presented by the TSP and NY. Therefore, in its different forms, yeast can be applied as a functional and technological ingredient in the food industry, with significant technological capabilities and potential applications.

The use of brewer`s yeast to replace textured soy protein (TSP) in burgers was investigated. Three formulations were made, corresponding to a control formulation with 4% TSP, a formulation containing 4% yeast cells in their natural state, and a formulation made with 4% mechanically ruptured yeast cells, which were characterized for the chemical, technological, and sensory properties. Significant differences were observed for pH and instrumental color between the formulations, with no changes in the visual color evaluation by the untrained assessors. The addition of yeast cells resulted in a higher cooking yield and lower reduction in diameter, contributing to maintaining the shape and juiciness of burgers, which is a positive aspect from the technological point of view. The TSP-based formulation presented higher overall appearance and flavor scores when compared with the other formulations, with no significant differences for the other sensory attributes. The results showed that debittering of yeast-cell biomass is required to remove hop resins and tannins before using in burgers, aimed to improve the product`s acceptance and the purchase intent. The debittered yeast cell biomass can be used in burger formulations with great potential to replace TSP, as an alternative to obtain a free allergen meat product.

Modification of the characteristics of polymeric membranes is regarded as an alternative to control the flux decline caused by the concentration polarization and the fouling in ultrafiltration (UF). This work investigated the use of dopamine (DA) and polyethyleneimine (PEI) to hydrophilize the surface and to improve the performance of a 50 kDa polyethersulfone UF membrane. The hydraulic permeance of membranes was investigated for the membranes modified using a DA solution with its concentration fixed at 2 mg·mL -1 and a PEI solution with its concentration varying from 0 to 16 mg·mL -1 . The membrane modified in a 16 mg·mL -1 solution of PEI presented the uppermost hydraulic permeance (33 L·h-1·m -2 ). This membrane and two other controls (unmodified and modified membranes with a 2 mg·mL -1 solution of DA) were further characterized for surface chemistry using Fourier transform infrared by attenuated reflectance (FTIR-ATR) and X-ray excited photoelectron spectroscopy (XPS) charge (zeta potential), morphology (field emission scanning electron microscopy (FESEM) and optical interferometry), water mass gain, and performance in bovine serum albumin (BSA) UF. XPS showed an increase in the nitrogen content and a decrease in the sulfur content indicating the membrane modification. Membrane modification with DA/PEI caused an increase in hydrophilicity, which could reduce the interaction of BSA with the membrane surface. The flux of protein solutions was improved by 400%, and there was a complete recovery of the water flux after chemical cleaning of the modified membrane.

Lipases are enzymes that can be secreted by several microorganisms, making interesting the biodiversity exploration for searching new microorganisms able to produce these enzymes. Many agro-industrial residues can be used as potential substrates for production of enzymes. The main objective of this work was the isolation and screening of microorganisms with potential to produce lipases. Among 24 fungi, five were selected as good lipase producers using tributyrin on agar plates and solid state fermentation of soybean bran. Two of them were isolated from soil samples, another two from soybean bran, and one from dairy products. These fungi were identified by microcultivation technique as from Penicillium and Aspergillus genera. Through random amplified polymorphic DNA technique, the most promising strains could be genetically discriminated, selecting two fungi as good lipase producers but genetically different. One isolated from soybean bran could hydrolyze efficiently triglycerides with fatty acids with different chain length. Another isolated from dairy products was only effective to hydrolyze triglycerides with long-chain fatty acids. Two distinct groups could be verified by means of this technique, comprising the most productive strains and the lowest or nonproductive ones in terms of hydrolytic activity.

Spent yeast biomass is one of the residues of brewing. It is specifically the second-largest residue from brewing industry. Most of the spent yeast is sold at low prices, or disposed as waste or used as animal feed. Spent yeast biomass is predominantly composed of proteins, and it has a high biological value, being an excellent source of high-quality protein, comparable in value with soy protein. Therefore, spent yeast biomass has great potential for use in foodstuffs for human consumption. The objective of this work was to evaluate the influence of cell rupture over the drying kinetics of spent yeast biomass using mathematical models (Lewis and Page). Also, to verify the influence of cell rupture method over the amount of protein. The cellular rupture was performed by two methods (chemical method and physical method: ultrasound). The drying process was performed by freeze-drying, and the parameters of the models were obtained using the non-linear regression (Generalized Reduced Gradient Nonlinear Optimization Code). Mathematical models of drying kinetics showed a strong correlation with the experimental data, R² > 0.96. The disruption process did not significantly affect the drying time and protein content. But the cellular autolysis improves the protein digestibility since the proteins will be totally available to the digestive enzymes and also increase the bioavailability of nutrients.

Constant monitoring of milk quality by the processing industries demands the use of methodologies that add agility and low-cost analysis, such as the use of electronic equipment based on infrared or ultrasonic spectroscopy. In the present study, quality of raw milk received by dairy farms from western region of Santa Catarina state, Brazil, was evaluated throughout two methodologies of analysis of chemical composition and compared, being that both equipment used standard procedures for calibration, considering as reference data from the classic analytical methods recommended in Brazilian legislation. Milk samples from 45 producers were analyzed for SCC, TBC and physicochemical analysis, performed at dairy’s laboratory and at the official laboratory. Infrared and ultrasound methodologies for chemical composition of fat, protein and lactose were compared and correlated. The comparison of the methods showed that there was no significant difference for the mean values of fat (P=0.06); however, they presented significant difference for protein (P=0.001), higher for IR (3.23 vs. 3.33), and lactose (P<0.0001), higher for US (4.47 vs. 4.83). Correlation was positive and significant for fat (r=0.73, P<0.0001), protein (r=0.47, P=0.001) and lactose (r=0.51, P=0.0003). Considering the minimal composition required, TBC and SCC levels, 95.5%, 84.1% and 64.4% of the milk producers met the current Brazilian legislation, respectively. It was concluded that the methodologies have affected results, which may have been influenced by the correction factor used for equipment calibration, specifically for analyzed samples during the study period. RESUMO: O monitoramento constante da qualidade do leite por parte das indústrias beneficiadoras demanda o uso de metodologias que agregam agilidade e baixo custo por análise, como a utilização de equipamentos eletrônicos que podem ter como princípio a espectroscopia por infravermelho ou por ultrassom. No presente estudo, avaliou-se a qualidade do leite recebido por um laticínio da região extremo oeste catarinense e comparou-se duas metodologias de análise de composição química desta matéria prima, sendo que ambos os equipamentos utilizaram procedimentos padrões para calibração, considerando como referência os dados oriundos dos métodos analíticos clássicos preconizados na legislação Brasileira. Foram comparadas amostras de leite de 45 produtores para análise físico-química, de CCS e CBT, realizadas no laboratório do laticínio e em laboratório oficial. As metodologias por infravermelho (IR) e ultrassom (US) foram comparadas e correlacionadas para composição química de gordura, proteína e lactose. Os resultados demonstraram que não houve diferença significativa para as médias de gordura (P=0,06), entretanto, apresentaram diferença para proteína (P=0,001), maior para IR (3,23 vs. 3,33), e lactose (P<0,0001), maior para US (4,47 vs. 4,83). A correlação foi positiva e significativa para gordura (r=0,73, P<0,0001), proteína (r=0,47, P=0,001) e lactose (r=0,51, P=0,0003). Os resultados das análises de qualidade, considerando composição, CBT e CCS, atenderam a legislação vigente em 95,5%, 84,1% e 64,4% dos produtores, respectivamente. Concluiu-se que as metodologias afetaram os resultados, e estes podem ter sido influenciados pelo fator de correção, utilizado para calibração, sendo específicos para as amostras analisadas durante o período do estudo.

Current studies about lipase production involve the use of agro-industrial residues and newly isolated microorganisms aimed at increasing economic attractiveness of the process. Based on these aspects, the main objective of this work is to perform the partial characterization of enzymatic extracts produced by a newly isolated Penicillium crustosum in solid-state fermentation. Lipase extract presented optimal temperature and pH of 37 °C and 9–10, respectively. The concentrated enzymatic extract showed more stability at 25 °C and pH 7. The enzymes kept 100% of their enzymatic activity until 60 days of storage at 4 and −10 °C. The stability under calcium salts indicated that the hydrolytic activity presented decay with the increase of calcium concentration. The specificity under several substrates indicated good enzyme activities in triglycerides from C4 to C18.

This study evaluated the production of cellulolytic enzymes from different agricultural residues. The crude enzyme extract produced was characterized and applied for saccharification of some agricultural residues. Maximum cellulolytic activities were obtained using soybean hulls. All enzymatic activities were highly stable at 40 °C at a pH range of 4.5–5.5. For stability at low temperatures, the enzyme extract was stored at freezing temperature and cooling for about 290 days without major loss of activity. The Km values found for total cellulase (FPase), endoglucanase (CMCase), and xylanase were 19.73 mg ml−1, 0.65 mg ml−1, and 22.64 mg ml−1, respectively, and Vmax values were 0.82 mol min−1 mg−1, 0.62 mol min−1 mg−1, and 104.17 mol min−1 mg−1 to cellulose, carboxymethyl cellulose, and xylan, respectively. In the saccharification tests, the total amount of total reducing sugars (TRS) released from 1 g of soybean hulls catalyzed by the enzymes present in the crude enzyme extract was 0.16 g g−1 dry substrate.

This work aimed to assess the effect of some variables on the lipase extraction from the fermented medium in order to establish the experimental conditions that maximize the yield of the enzyme obtained from solid-state fermentation of soybean meal and a newly isolated strain of Penicillium sp. The experimental design technique was used to investigate the effect of relevant variables on lipase activity. The factors investigated were solvent pH (5.5-8.5), stirring rate (50-150 rpm), temperature (25-49 °C) and solid/liquid ratio (1:20-5:20). The effect of time of contact was evaluated in a kinetic study. Higher lipase activities in the extraction study were obtained using phosphate buffer 100 mM pH 8.5, at 25 °C, 150 rpm, and solid/liquid ratio of 1:20. Extraction studies showed that maximum activity (186 U/g) was obtained in 15 min of extraction.