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Hexanal is an essential oil component which has quorum sensing (QS) inhibitor effect on vegetable spoilage bacteria such as Erwinia carotovora (E. carotovora) and Pseudomonas fluorescens (P. fluorescens). However, the QS inhibitory (QSI) effect of hexanal on Autoinducer‐2 (AI‐2), biofilm formation, and enzyme activity is not well understood. Our results showed that the contents of AI‐2 produced by E. carotovora were higher than P. fluorescens, and the 4,5‐Dihydroxy‐2,3‐pentanedione (DPD) concentrations were significantly (p <.05) inhibited by hexanal. Adding DPD exogenously could form more biofilm when inhibited by 1/2 of minimum inhibitory concentration (MIC) of hexanal, which showed that QSI effect of hexanal on biofilm was due to its inhibition on AI‐2. There was no significant increase in enzyme activity, which suggested that enzyme inhibition by hexanal may not due to AI‐2. Understanding the relationship between QSI effect of hexanal on AI‐2, biofilm formation, and enzyme activity can improve to suppress decomposition of vegetables after harvest. Practical applications: Hexanal is an EO component which has shown good QSI effect on biofilm formation and exoenzyme activities of P. fluorescens and E. carotovora. However, the reason for the QSI effect of hexanal was still unclear. In this study, hexanal as a QS inhibitor on these two vegetable spoilage bacteria was studied from the perspective of AI‐2 signal molecule. Understanding the QS inhibition of hexanal on AI‐2 signal molecule of spoilage bacteria and its relationship with biofilm formation and enzyme activity was necessary for the application of more EO components as QS inhibitor to suppress corruption of vegetables after harvest. [ABSTRACT FROM AUTHOR]

In this work, corn porous starch was used as a food grade polymer to microencapsulate essential oil (EO), the effects of temperature on adsorption of EO were investigated, and adsorption kinetics curves were plotted. Using this approach, the sustained‐release antibacterial effects of porous starch microcapsules containing EOs (PSM‐EOs) against Penicillium roqueforti and Aspergillus niger were explored under accelerated volatilization under high temperature conditions, and microencapsulation was successfully applied to bread preservation. The results showed that temperature had a significant effect on the adsorption capacity, and adsorption rate was controlled by both liquid film diffusion and intraparticle diffusion. The activation energy (Ea) of the adsorption process was 7.96 K J/mol as calculated using the Arrhenius equation. The results of antibacterial experiments showed that PSM‐EOs exhibited superior sustained‐release antibacterial effects and significantly prolonged the shelf life of bread, compared with controls. Practical applications: The spoilage caused by mold contamination is a serious challenge for the bread industry. At present, the main preservative used in baking products is calcium propionate, a chemical preservative. However, calcium propionate can be decomposed to produce propionic acid under the action of intestinal microorganisms. Propionic acid is an important factor in inducing diabetes mellitus. Therefore, it is necessary to explore new preservation techniques rather than bread with calcium propionate. In this paper, porous starch microcapsules containing essential oil were prepared, and the adsorption kinetics curve of porous starch to essential oil was plotted. On this basis, the inhibition effect of porous starch microcapsules containing essential oil in high temperature accelerated volatilization on the main mold (P. roqueforti and A. niger) causing bread corruption was investigated. The aim is to provide new ideas for bread preservation. [ABSTRACT FROM AUTHOR]

This work studied the ability of Bacillus subtilis and Bacillus natto to degrade zearalenone (ZEN) and analyzed the amounts of ZEN in cell residues. The effect of different processing conditions on the degradation capacity of the bacteria was then analyzed. Finally, B. subtilis and B. natto were applied to food. The results showed that at 48 hr, the degradation rates of the two taxa were 100% and 87%, and the amount of ZEN in the cell residues were 2.3% and 1.6%, respectively; no residual ZEN was found in the supernatant of B. subtilis. Acidification treatment showed a lower degradation effect compared with autoclaving. For liquid food, the two taxa had the best degradation effect in beer, 65% and 73%, respectively. In solid‐state fermentation (SSF), B. subtilis and B. natto had the strongest degradation effect in corn flour and soybean flour, respectively, and their degradation activities were 75% and 70%, respectively. Practical applications: The evaluation of the degradation potential of B. natto, an important probiotic, for ZEN has not been reported. It was found that B. natto and B. subtilis have a significant degradation effects on ZEN in food. When the two taxa were applied to liquid foods and SSFs, they were found to have a promising degradation effect on ZEN as well. This discovery is of great significance for the degradation of ZEN in food. [ABSTRACT FROM AUTHOR]