Zietsman Anscha J J, Moore John P, Fangel Jonatan U, Willats William G T, Vivier Melané A
Institute for Wine Biotechnology, Department of Viticulture and Oenology, Faculty of AgriSciences, Stellenbosch University, Matieland 7602, South Africa.
Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, DK-1001, Denmark.
Food Chem. 2017 Oct 1;232:340-350. doi: 10.1016/j.foodchem.2017.04.015. Epub 2017 Apr 6.
Chardonnay grape pomace was treated with pressurized heat followed by enzymatic hydrolysis, with commercial or pure enzymes, in buffered conditions. The pomace was unfermented as commonly found for white winemaking wastes and treatments aimed to simulate biovalorization processing. Cell wall profiling techniques showed that the pretreatment led to depectination of the outer layers thereby exposing xylan polymers and increasing the extractability of arabinans, galactans, arabinogalactan proteins and mannans. This higher extractability is believed to be linked with partial degradation and opening-up of cell wall networks. Pectinase-rich enzyme preparations were presumably able to access the inner rhamnogalacturonan I dominant coating layers due to the hydrothermal pretreatment. Patterns of epitope abundance and the sequential release of cell wall polymers with specific combinations of enzymes led to a working model of the hitherto, poorly understood innermost xyloglucan-rich hemicellulose layers of unfermented grape pomace.
霞多丽葡萄果渣在缓冲条件下先进行加压加热处理，然后用商业酶或纯酶进行酶解。该果渣未发酵，这是白葡萄酒酿造废弃物常见的情况，且处理旨在模拟生物转化过程。细胞壁分析技术表明，预处理导致外层果胶去除，从而使木聚糖聚合物暴露，并提高阿拉伯聚糖、半乳聚糖、阿拉伯半乳聚糖蛋白和甘露聚糖的可提取性。据信，这种更高的可提取性与细胞壁网络的部分降解和开放有关。由于水热预处理，富含果胶酶的酶制剂大概能够进入内部以鼠李糖半乳糖醛酸聚糖I为主的包被层。表位丰度模式以及特定酶组合导致细胞壁聚合物的顺序释放，从而形成了一个关于迄今尚未得到充分理解的未发酵葡萄果渣最内层富含木葡聚糖的半纤维素层的工作模型。
