Department of Food Engineering, Faculty of Engineering, Adana Alparslan Türkeş Science and Technology University, Adana 01250, Turkey.
Department of Food Engineering, Faculty of Engineering, Ankara University, 50. Yıl Campus, Gölbaşı 06830, Ankara, Turkey.
Food Chem. 2021 Aug 1;352:129321. doi: 10.1016/j.foodchem.2021.129321. Epub 2021 Feb 19.
Low turbidity and low discolouration is targeted in clear red grape juice (RGJ) production. Depending on type of clarification agents, substantial discolouration may occur. Therefore, this study was undertaken to show effects of various clarification treatments (bentonite and chitosan, and combinations of "bentonite + gelatin (B + G)," "bentonite + casein (B + CA)," "bentonite + albumin (B + A)" and "bentonite + chitosan (B + CTS)" on turbidity, color (ACNs, color density-CD and polymeric color-PC), phenolics and antioxidant activity (AOA) during RGJ clarification. Casein alone (4.0 NTU and 9.1% ACN loss) and in combination with bentonite (4.4 NTU and 12.3% ACN loss), followed by B + A (5.7 NTU and 12.3% ACN loss) resulted in best clarity and was associated with least change in ACNs. These clarifications also resulted in high CD (intensive red color) and low PC (low browning). At all dosages, gelatin and albumin were associated with highest ACN losses, while casein in greatest retention. "Bentonite + casein," followed by "bentonite + albumin," achieved the best clarification of RGJ.
低浊度和低变色是澄清红葡萄汁（RGJ）生产的目标。根据澄清剂的类型，可能会发生明显的变色。因此，本研究旨在展示各种澄清处理（膨润土和壳聚糖，以及“膨润土+明胶（B+G）”、“膨润土+酪蛋白（B+CA）”、“膨润土+白蛋白（B+A）”和“膨润土+壳聚糖（B+CTS）”）对浊度、颜色（ACNs、颜色密度-CD 和聚合颜色-PC）、酚类物质和抗氧化活性（AOA）的影响，以澄清 RGJ。单独的酪蛋白（4.0 NTU 和 9.1% 的 ACN 损失）和与膨润土结合（4.4 NTU 和 12.3% 的 ACN 损失），其次是 B+A（5.7 NTU 和 12.3% 的 ACN 损失），可获得最佳的澄清度，并与 ACNs 的最小变化相关。这些澄清处理还导致高 CD（强烈的红色）和低 PC（低褐变）。在所有剂量下，明胶和白蛋白与最高的 ACN 损失相关，而酪蛋白的保留率最高。“膨润土+酪蛋白”，其次是“膨润土+白蛋白”，对 RGJ 的澄清效果最佳。
