Effect of polysaccharides on the gel characteristics of "Yu Dong" formed with fish (Cyprinus carpio L.) scale aqueous extract
FOOD CHEMISTRY
Authors: Li, Jun; Tang, Wenjiao; Lei, Zunguo; Wang, Zhenyu; Liu, Jia
Abstract
A novel protein-based gel named "Yu dong" prepared with fish (Cyprinus carpio L.) scale aqueous extract and enhanced by polysaccharides is described in this study. The effects of pectin, alginate, and sodium carboxyl methyl cellulose (CMC-Na) on FS gel formation, stability, textural characteristics, microstructure, and water distribution were evaluated. The results indicated the viscosity of the FS gels decreased and changed slowly as the addition of pectin. While, the addition of alginate enhanced the formation of FS gels. As pectin addition in FS gels, the transition temperature decreased. When alginate and CMC-Na was added to the FS gels, the transition temperature increased. The addition of pectin, alginate, and CMC-Na to the FS gels significantly increased G(r) from 44.5% to 71.99%, 61.86%, and 71.35%, respectively. Gel strength increased significantly as the addition of pectin, alginate, and CMC-Na. LF-NMR results showed that a moderate amount (0.2%) of polysaccharides bonded the protein and water more tightly, which was consistent with the SEM results showing gel structure with more uniform pores. This study provides a direct application of FS protein in preparing of gel food, which showing a better way to utilize the abandoned fish resource.
The outer influences the inner: Postharvest UV-B irradiation modulates peach flesh metabolome although shielded by the skin
FOOD CHEMISTRY
Authors: Santin, Marco; Ranieri, Annamaria; Hauser, Marie-Theres; Miras-Moreno, Begona; Rocchetti, Gabriele; Lucini, Luigi; Stride, Ake; Castagna, Antonella
Abstract
UV-B-driven modulation of secondary metabolism in peach fruit by enhancing the biosynthesis of specific phenolic subclasses, is attracting interest among consumers. However, current literature explored the UV-B-induced metabolic changes only in peach skin subjected to direct UV-B irradiation. Accordingly, this study aimed to understand whether UV-B radiation penetrates the fruit skin and is able to induce metabolic changes also within the inner flesh. Peaches were UV-B-irradiated either 10 or 60 min, and the flesh was sampled after 24 and 36 h. Non-targeted metabolomics revealed that UV-B has a strong impact on peach flesh metabolome, determining an initial decrease after 24 h, followed by an overall increase after 36 h, particularly for terpenoids, phenylpropanoids, phytoalexins and fatty acids in the 60 min UV-B-treated samples (+150.02, +99.14, +43.79 and +25.44 log(2)FC, respectively). Transmittance analysis indicated that UV-B radiation does not penetrate below the skin, suggesting a possible signalling pathway between tissues.