Suchergebnisse

Yan yu is a traditional fermented fish product produced by the Dong people of Guizhou Province in southwestern China. However, despite its widespread regional consumption, little is known about the chemical characteristics and bacterial community changes involved during yan yu fermentation. Therefore, the present work assessed the changes in both the chemical and microbiota composition of yan yu during its fermentation. Glucose levels gradually decreased after an initial increase at the beginning of fermentation, whereas increase in lactic acid levels continued after 10 d of fermentation. A rapid increase in free amino acid levels was observed at the beginning, but either remained constant or slowly decreased later in the fermentation. In contrast, biogenic amine (BA), TVB-N, and TBARS levels remained low throughout the fermentation. Bacterial community analyses revealed that Lactiplantibacillus and Tetragenococcus dominated the bacterial community. Moreover, O2PLS-based correlation analysis indicated that these two genera significantly affected the chemical composition of yan yu. Furthermore, lactic acid and free amino acid contents (i.e., two major quality parameters of fermented products) were highly correlated with the occurrence of Lactiplantibacillus and Tetragenococcus. These results are expected to establish a basis for the quality improvement of traditional fermentation of yan yu.

To improve the preservation of strawberries during storage, an edible coating was prepared using a layer-by-layer self-assembly electrostatic deposition technology. Sodium polyacrylate (PAAS) was used as polyanion solution, and chitosan (CS) was used as polycation solution. The obtained coating was characterised to determine its self-repairing ability and its effect on the preservation of strawberries. The results showed that CS (9 mg/mL) and PAAS (5 mg/mL) could assemble, by hydrogen and ionic bonding, to form a new coating with no obvious pores and had a tight cross-sectional structure. The PAAS/CS self-assembled coating displayed high water resistance (water vapor transmission rate, 31.22 × 10-11 g• m/m2•s•Pa·), transparency (light transmittance, 87.5%), and excellent mechanical properties (tensile strength, 17.31 MPa; elongation at break, 13.72%). The self-repairing ability of the PAAS/CS coating upon scratching was manifested by the repair of the coating's morphology (repair rate, 81.05%), and the restoration of its mechanical properties. When compared with uncoated strawberries, PAAS/CS coating significantly reduced the weight loss rate, the rot rate during storage (p < 0.05), and the loss of anthocyanin and vitamin C. In conclusion, the PAAS/CS coating greatly improved the fresh-keeping of strawberries.

ABSTRACT: Limited resources and increasing environmental concerns have prompted calls to identify the critical questions that most need to be answered to advance conservation, thereby providing an agenda for scientific research priorities. Cetaceans are often keystone indicator species but also high profile, charismatic flagship taxa that capture public and media attention as well as political interest. A dedicated workshop was held at the conference of the Society for Marine Mammalogy (December 2013, New Zealand) to identify where lack of data was hindering cetacean conservation and which questions need to be addressed most urgently. This paper summarizes 15 themes and component questions prioritized during the workshop. We hope this list will encourage cetacean conservation-orientated research and help agencies and policy makers to prioritize funding and future activities. This will ultimately remove some of the current obstacles to science-based cetacean conservation.