Department of Food Engineering, Sorocaba Engineering College (FACENS), Senador José Ermínio de Moraes Road, 1425, 18085-784 Sorocaba, SP, Brazil.
Department of Food Technology (DTA), School of Food Engineering (FEA), University of Campinas (UNICAMP), Monteiro Lobato, 80. PO Box 6121, 13083-862 Campinas, SP, Brazil.
Food Res Int. 2020 Apr;130:108856. doi: 10.1016/j.foodres.2019.108856. Epub 2019 Dec 3.
The aim of this study was to investigate the effects of high hydrostatic pressure (HHP) on the inactivation of Lactobacillus fructivorans, on the inactivation of Alicyclobacillus acidoterrestris spores and on the extraction of anthocyanins and total phenolics from açaí pulp. The tested conditions comprised pressures of 400-600 MPa, treatment times of 5-15 min, and temperatures of 25 °C and 65 °C. Results were compared to those of conventional thermal treatments (85 °C/1 min). Regarding A. acidoterrestris spores, applying HHP for 13.5 min, resulted in a value of four-decimal reduction. L. fructivorans presented considerable sensitivity to HHP treatment, achieving inactivation rates above 6.7 log cycles at process conditions at 600 MPa and 65 °C for 5 min. All samples of açaí pulp processed showed absence of thermotolerant coliforms during the 28 days of refrigerated storage (shelf life study). The açaí pulps processed by HHP (600 MPa/5 min/25 °C) had anthocyanin extraction increased by 37% on average. In contrast, conventional thermal treatment reduced anthocyanin content by 16.3%. For phenolic compounds, the process at 600 MPa/5 min/65 °C increases extraction by 10.25%. A combination of HHP treatment and moderate heat (65 °C) was shown to be an alternative to thermal pasteurization, leading to microbiologically safe products while preserving functional compounds.
本研究旨在探究高静压（HHP）对以下方面的影响：嗜酸耐热菌（Alicyclobacillus acidoterrestris）孢子的失活动能、Lactobacillus fructivorans 的失活动能，以及从中提取阿萨伊（açai）浆的花色苷和总酚类物质。测试条件涵盖压力 400-600 MPa、处理时间 5-15 分钟以及温度 25°C 和 65°C。结果与传统热处理（85°C/1 分钟）进行比较。对于嗜酸耐热菌孢子，经 13.5 分钟 HHP 处理，可实现四位有效数字的降低值。L. fructivorans 对 HHP 处理极为敏感，在 600 MPa 和 65°C 下处理 5 分钟，即可实现超过 6.7 个对数循环的失活动能。在冷藏储存（保质期研究）28 天期间，所有经 HHP 处理的阿萨伊浆样品均未检出耐热大肠菌群。经 HHP（600 MPa/5 分钟/25°C）处理的阿萨伊浆花色苷提取率平均提高了 37%。相比之下，传统热处理会降低 16.3%的花色苷含量。对于酚类化合物，600 MPa/5 分钟/65°C 的处理过程可使提取量增加 10.25%。HHP 处理与适度热（65°C）相结合，是巴氏杀菌的替代方法，可在保证产品微生物安全性的同时保留功能性化合物。
