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This study investigates the aromatic composition of pea albumin and globulin fractions obtained through either fermentation or conventional acidification using hydrochloric acid (control) toward the isoelectric point of pea globulins. Different lactic acid bacteria were used including S. thermophilus (ST), L. plantarum (LP), and their coculture (STLP). The volatile compounds were extracted by solvent-assisted flavor evaporation technique and quantified by gas chromatography-mass spectrometry (GC-MS). Odor-active compounds (OAC) were further characterized by gas chromatography-olfactometry (GC-O). In total, 96 volatile and 36 OACs were identified by GC-MS and GC-O, respectively. The results indicated that the protein fractions obtained by conventional acidification were mainly described by green notes for the presence of different volatile compounds such as hexanal. However, the samples obtained by fermentation had a lower content of these volatile compounds. Moreover, protein fractions obtained by coculture fermentation were described by volatile compounds associated with fruity, floral, and lactic notes. PRACTICAL APPLICATION: The insights from this study on pea protein aroma could find practical use in the food industry to enhance the sensory qualities of plant-based products. By utilizing fermentation methods and specific lactic acid bacteria combinations, manufacturers may produce pea protein with reduced undesirable green notes, offering consumers food options with improved flavors. This research may contribute to the development of plant-based foods that not only provide nutritional benefits but also meet consumer preferences for a more appealing taste profile., (© 2024 The Author(s). Journal of Food Science published by Wiley Periodicals LLC on behalf of Institute of Food Technologists.)

This study conducted a seasonal analysis of bulk tank milk from 77 sheep farms to establish relationships between the concentration of major microbial groups and milk coagulation properties. The investigated milk traits included composition (pH, fat, casein, lactose), coagulation properties (curd firmness: A 60 -, rennet clotting time: RCT-, curd firming time: k 20 -, curd yield: CY-), and somatic cell score (SCS). The main microbial groups analyzed were total mesophilic bacteria (SPC), thermodurics (THERMO), psychrotrophs (PSYCHRO), Pseudomonas spp. (PSEUDO), lactic acid bacteria (LAB), catalase-negative gram-positive cocci (GPCNC), Escherichia coli (ECOLI), coliforms other than Escherichia coli (COLI), coagulase-positive staphylococci (CPS), coagulase-negative staphylococci (CNS), and spores of lactate-fermenting Clostridium (BAB). Mixed linear models were used to explore associations between coagulation properties and the aforementioned variables. Results demonstrated that incorporating microbial loads into the models improves their fit and the relative quality of the outcomes. An important seasonality is demonstrated by an increase in CY and A 60 , along with a decrease in RCT and k 20 during autumn and winter, contrasting with spring and summer. BAB concentration resulted in a reduction of A 60 and an increase in RCT, whereas SPC concentration led to an enhancement of A 60 and a reduction in RCT. An increase in GPCNC concentration was associated with an increase in k 20 and a decrease in CY.

Sheep milk from local breeds is important for the production of high-quality cheeses throughout the Mediterranean region, such as Manchego cheese in Spain. To maintain sustainable and efficient production, it is necessary to reach a better understanding of how the composition and hygiene of the milk affect the coagulation process, with the aim of optimizing production yield. This study implemented a stochastic production frontier function to estimate the potential production of curd and efficiency using data from the four seasons of a study of 77 Manchega sheep farms. The Cobb-Douglas production frontier model was estimated using the maximum likelihood estimation method. The results showed that the content of protein, lactose, and fat exhibited increasing returns to scale, with protein content being the most significant factor for curd production. Approximately half of the inefficiency was due to factors related to the technological properties and the hygiene of the milk. The pH, curd firmness, and concentration of lactic acid bacteria improved the efficiency of coagulation, while the concentration of spores of lactate-fermenting Clostridium spp., Pseudomonas spp., staphylococci, and catalase-negative gram-positive cocci favored the inefficiency of the coagulation process. To date, this is the first study to evaluate the effect of different factors, such as microbial groups, milk composition, and technological properties, on the efficiency of the coagulation process in dairy sheep.