Departamento de Ciencia y Tecnología de Alimentos, CEBAS-CSIC, P.O. Box 164, E-30100, Espinardo, Murcia, Spain.
Food Chem. 2013 Dec 1;141(3):2122-9. doi: 10.1016/j.foodchem.2013.04.118. Epub 2013 May 9.
Juices prepared from arils of 'Mollar' pomegranates were analysed for naturally occurring microorganisms, CIE Lab colour parameters, total phenols, anthocyanins and punicalagins, ellagic acid content and antioxidant capacity before and after low-, mild- and high-temperature pasteurisations (LTPs, MTPs and HTPs): 65, 80 and 90 °C for 30 or 60s. Mean aerobic plate count (APC), yeast and mold count (YMC), and lactic acid bacteria (LAB) for fresh juices were 5.7, 5.36 and 4.0 log CFU/mL, respectively. MTPs and HTPs were sufficiently effective to decrease APCs to nil or negligible levels. An increase in CIE a values and decrease in CIE b values were the characteristic colour changes in heat-treated juices. The effect of pasteurisations showed that total phenols, punicalagins and ellagic acid were not much affected by thermal processing. Total anthocyanin content and antioxidant capacity were substantially and significantly influenced by the heat treatment applied. A linear relationship was observed between Trolox equivalent antioxidant capacity (TEAC) values and total anthocyanins, suggesting that they contributed strongly to the antioxidant capacity of pomegranate juice.
从“Mollar”石榴的种籽中制备的果汁，经过低温巴氏杀菌（LTPs）、中温巴氏杀菌（MTPs）和高温巴氏杀菌（HTPs）：65、80 和 90°C 下 30 或 60 秒，分别分析了其中的天然存在微生物、CIE Lab 颜色参数、总酚类、花青素和安石榴苷、鞣花酸含量和抗氧化能力。新鲜果汁的好氧平板计数（APC）、酵母和霉菌计数（YMC）和乳酸菌（LAB）平均值分别为 5.7、5.36 和 4.0 log CFU/mL。MTPs 和 HTPs 足以有效地将 APC 降低至零或可忽略的水平。热处理果汁的特征颜色变化是 CIE a 值增加和 CIE b 值降低。巴氏杀菌的影响表明，总酚类、安石榴苷和鞣花酸不受热加工的影响。总花青素含量和抗氧化能力受到所应用的热处理的显著影响。在 Trolox 当量抗氧化能力（TEAC）值和总花青素之间观察到线性关系，表明它们对石榴汁的抗氧化能力有很强的贡献。
