Department of Food Science and Technology , University of California, Davis , One Shields Avenue , Davis , California 95616 , United States.
J Agric Food Chem. 2018 Aug 1;66(30):8045-8053. doi: 10.1021/acs.jafc.8b02250. Epub 2018 Jul 18.
Red grape pomace (RGP), a byproduct of red wine production, is an abundant food processing waste stream in California, rich in both anthocyanins, a class of red-blue pigments, and lignocellulose. Extraction of anthocyanins and biofuel production from RGP have been investigated independently, but no research has examined employing both strategies together for maximal valorization. In this study, anthocyanins were most effectively extracted from RGP at 80 °C. Convection- and vacuum-oven drying of the pomace were found to decrease anthocyanin yield, whereas lyophilization did not significantly affect yield. Fermentable sugars were successfully separated from the crude extract via solid-phase extraction. Ionic liquid pretreatment of RGP was determined to be a nonviable option for application to anaerobic digestion. Extraction reduced biomethane output, but supplementation with the aqueous fraction of the extract mitigated much of this difference, indicating sequential extraction and fractionation of anthocyanins from RGP can minimize the impact on biofuel yields.
红葡萄渣（RGP）是葡萄酒生产的副产物，在加利福尼亚州是一种丰富的食品加工废料，富含花色苷和木质纤维素。人们已经分别研究了从 RGP 中提取花色苷和生产生物燃料，但没有研究考察同时采用这两种策略以实现最大价值。在这项研究中，最有效地在 80°C 下从 RGP 中提取花色苷。发现对流和真空烘箱干燥会降低花色苷的得率，而冻干则对产率没有显著影响。通过固相萃取成功地将可发酵糖从粗提取物中分离出来。离子液体预处理 RGP 被确定为不可行的选择，不适用于厌氧消化。提取会降低生物甲烷的产量，但用提取物的水相进行补充可以缓解大部分差异，这表明从 RGP 中顺序提取和分离花色苷可以最小化对生物燃料产量的影响。
