Abstract:
In order to valorise winemaking grape stalks, subcritical water extraction at 160 and 180 °C has been carried out to obtain phenolic-rich extracts useful for developing active food packaging materials. Red (R) and white (W) varieties (from Requena, Spain) were used, and thus, four kinds of extracts were obtained. These were characterised as to their composition, thermal stability and antioxidant and antibacterial activity. The extracts were incorporated at 6 wt% into polylactic acid (PLA) films and their effect on the optical and barrier properties of the films and their protective effect against sunflower oil oxidation was analysed. Carbohydrates were the major compounds (25-38%) in the extracts that contained 3.5-6.6% of phenolic compounds, the R extracts being the richest, with higher radical scavenging capacity. Every extract exhibited antibacterial effect against Escherichia coli and Listeria innocua, while PLA films with extracts preserved sunflower oil against oxidation.
摘要:
为了使酿酒葡萄茎增值,已在160和180°C下进行了亚临界水提取,以获得可用于开发活性食品包装材料的富含酚的提取物。红色(R)和白色(W)品种(来自Requena,西班牙)被使用,因此,获得了四种提取物。这些被表征为它们的组成,热稳定性和抗氧化和抗菌活性。将提取物以6wt%的含量掺入聚乳酸(PLA)薄膜中,并分析了它们对薄膜的光学和阻隔性能的影响以及它们对向日葵油氧化的保护作用。碳水化合物是提取物中含有3.5-6.6%酚类化合物的主要化合物(25-38%),R提取物是最丰富的,具有较高的自由基清除能力。每种提取物都对大肠杆菌和无毒李斯特菌具有抗菌作用,而带有提取物的PLA膜保存了葵花籽油的抗氧化作用。