Extracts from fruit processing by-products usually present high amounts of bioactive compounds with several important activities such as antioxidant and antimicrobial capacities. In this work we studied (i) the cytotoxicity profile of pomegranate peel extract and (ii) safety and quality aspects after incorporating this extract in carrot juice - a beverage with low antioxidant potential and highly prone to microbial growth. The extract was obtained by high-pressure extraction and was non-cytotoxic towards the Caco-2 cell line after in vitro digestion. The non-cytotoxic pomegranate peel extract was added to carrot juice in a concentration of 5 mg mL-1. Fortified juices were processed by high-pressure and conventional heat and stored under refrigeration. On the 28th day of storage, microbial counts in PPE-fortified juices were reduced by 1.0 log10 CFU mL-1 and the pressurized juices showed significantly fewer counts than the thermal-treated ones. Just after processing, phenolic and flavonoid contents, as well as ABTS and FRAP antioxidant capacities, increased 3.6, 3.5, 8.2, and 9.4-fold, respectively in the fortified juices. The extract addition did not affect any colour parameter and all studied physicochemical parameters i.e. total soluble solids, pH, colour, total phenolics, flavonoids, hydrolysable tannins, and antioxidant capacity remained constant throughout storage. These findings could pave the way towards the development of safe beverages with improved bioactive properties.

中文翻译：

---

研究石榴皮高压提取物改善胡萝卜汁特性的可行性。

水果加工副产品中的提取物通常具有大量具有某些重要活性（例如抗氧化剂和抗菌能力）的生物活性化合物。在这项工作中，我们研究了（i）石榴皮提取物的细胞毒性特征，以及（ii）将这种提取物掺入胡萝卜汁中后的安全性和质量方面。胡萝卜汁是一种抗氧化剂含量低且极易发生微生物生长的饮料。提取物通过高压提取获得，并且在体外消化后对Caco-2细胞系无细胞毒性。将无细胞毒性的石榴皮提取物以5 mg mL-1的浓度添加到胡萝卜汁中。强化果汁通过高压和常规加热处理，并在冷藏条件下存储。在储存的第28天，PPE强化果汁中的微生物数量减少了1。0 log10 CFU mL-1和加压果汁显示的计数明显少于热处理果汁。刚加工后，强化果汁中的酚和类黄酮含量以及ABTS和FRAP抗氧化能力分别增加了3.6倍，3.5倍，8.2倍和9.4倍。提取物的添加不会影响任何颜色参数，所有已研究的理化参数，即总可溶性固形物，pH，颜色，总酚类，类黄酮，可水解单宁和抗氧化能力在整个存储过程中均保持不变。这些发现可能为开发具有改善的生物活性的安全饮料铺平道路。强化果汁分别增加了3.6倍，3.5倍，8.2倍和9.4倍。提取物的添加不会影响任何颜色参数，所有已研究的理化参数，即总可溶性固形物，pH，颜色，总酚类，类黄酮，可水解单宁和抗氧化能力在整个存储过程中均保持不变。这些发现可能为开发具有改善的生物活性的安全饮料铺平道路。强化果汁分别增加了3.6倍，3.5倍，8.2倍和9.4倍。提取物的添加不会影响任何颜色参数，所有已研究的理化参数，即总可溶性固形物，pH，颜色，总酚类，类黄酮，可水解单宁和抗氧化能力在整个存储过程中均保持不变。这些发现可能为开发具有改善的生物活性的安全饮料铺平道路。