Probiotics are sensitive to phenolic antibacterial components and the extremely acidic environment of blueberry juices. Layer-by-layer (LbL) coating using whey protein isolate fibrils (WPIFs) and sodium alginate (ALG), carboxymethyl cellulose (CMC), or xanthan gum (XG) was developed to improve the survival rate of Lactobacillus plantarum 90 (LP90) in simulated digestion, storage, and fermented blueberry juices. The LbL-coated LP90 remained at 6.65 log CFU/mL after 48 h of fermentation. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) indicated that dense and rough wall networks were formed on the surface of LP90, maintaining the integrity of LP90 cells after the coating. Stability evaluation showed that the LbL-coated LP90 had a much higher survival rate in the processes of simulated gastrointestinal digestion and storage. The formation mechanism of the LbL coating process was further explored, which indicated that electrostatic interactions and hydrogen bonding were involved. The LbL coating approach has great potential to protect and deliver probiotics in food systems.

In this study we investigated the influence of rice wine (Jinbiao, Yinbiao, Wunianchen, Nv’erhong) on the activity of endogenous proteases, myofibrillar degradation and quality characteristics in topmouth culter muscle. Rice wines had pH of about 4.3, and micromolar level of calcium ions. Nv’erhong (NEH) had the highest total phenolics content, while Wunianchen (WNC) showed the strongest total antioxidant capacity. WNC showed the considerable inhibitory action on the endogenous proteases, and delayed the degradation of myosin heavy chain and α-actinin, which occurred more quickly in other groups, especially in blank and alcohol controls. Total volatile base nitrogen production and texture profile for the fish fillets confirmed the improvement role of rice wine on the quality. In general, rice wine can inhibit the endogenous proteases and reduce the extent of myofibrillar degradation on the combined role of acidic pH and antioxidative components, resulting in the maintaining of good quality of the fish.

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