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Today, cheese is valued because of its high nutritional value and unique characteristics. Improving the texture and flavor of cheese by selecting suitable starter cultures is an important way to promote the development of cheese industry. The effect of starter cultures on the physicochemical and textural properties and volatile compounds during the ripening of semihard goat cheese were investigated in this work. Different starter cultures-mesophilic (M) and thermophilic starters (T), Lactobacillus plantarum ssp. plantarum ATCC 14917 (Lp), a mix of the M and T starters (M1), and mix of the M, T, and Lp starters (M2)-were used in the production of the goat cheeses. Volatile compounds were determined by a solid-phase microextraction/gas chromatography-mass spectrometric (SPME/GC-MS) method. The results showed that the moisture content of cheeses produced with the 5 kinds of starter cultures decreased after maturation, whereas ash content increased. The pH values of goat cheeses decreased first and then increased during maturity, and the pH value of M2 cheese was the lowest among the cheeses. The hardness and chewiness of the cheeses increased with increasing maturity, whereas cohesiveness, springiness, and resilience showed the opposite tendency. The 60-dold cheese made with Lp had the highest chewiness, cohesiveness, springiness, and resilience, whereas the 60-d-old cheese made with M2 had the highest hardness. A total of 53 volatile components were identified by SPME/GC-MS, and carboxylic acids, alcohols, ketones, and esters were the 4 major contributors to the characteristic flavors of the cheeses. Volatile components and their contents differed greatly among the produced cheeses. The M2 cheese contained the highest relative content of the main volatile compounds (90.10%), especially butanoic acid and acetoin. Through a comprehensive comparison of the results, we concluded that M2 cheese had a dense texture and milky flavor, and M2 is a potential starter culture candidate for the production of goat cheese.

The extraction of phenolics from jujube peel (PJP) was optimized using response surface methodology (RSM). A Box–Behnken design was utilized to analyze the effects of NaOH concentration, temperature, and extraction time on the total phenolic content (TPC). The results showed that RSM could be an adequate approach for modeling the extraction of PJP. The optimal extraction condition for the highest TPC was obtained with 3.4 M NaOH concentration for 67 min at 50 °C. Not only PJP but also phenolics from the jujube seed (PJS) contain considerable amounts of phenolics, particularly flavonoids. Quercetin and galangin were found to be the predominant phenolics. PJP markedly down-regulated the levels iNOS and COX-2 proteins in macrophages by inhibiting the activation of NF-κB through interfering with the MAPK signaling pathways. Compared to PJS, PJP presented higher anti-inflammatory activities, reflecting increased amounts of TPC and total flavonoid content (TFC). These findings suggest that PJP could be a potential source of anti-inflammatory agents.

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