Department of Chemical and Materials Engineering, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Department of Chemical Engineering, University of Riau, Pekanbaru 28293, Indonesia.
Department of Chemical and Materials Engineering, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
Int J Food Microbiol. 2015 Dec 2;214:129-136. doi: 10.1016/j.ijfoodmicro.2015.07.031. Epub 2015 Aug 1.
Byssochlamys nivea is a mold that can spoil processed fruit products and produce mycotoxins. In this work, high pressure processing (HPP, 600 MPa) and power ultrasound (24 kHz, 0.33 W/mL; TS) in combination with 75°C for the inactivation of four week old B. nivea ascospores in strawberry puree for up to 30 min was investigated and compared with 75°C thermal processing alone. TS and thermal processing can activate the mold ascospores, but HPP-75°C resulted in 2.0 log reductions after a 20 min process. For a 10 min process, HPP-75°C was better than 85°C alone in reducing B. nivea spores (1.4 vs. 0.2 log reduction), demonstrating that a lower temperature in combination with HPP is more effective for spore inactivation than heat alone at a higher temperature. The ascospore inactivation by HPP-thermal, TS and thermal processing was studied at different temperatures and modeled. Faster inactivation was achieved at higher temperatures for all the technologies tested, indicating the significant role of temperature in spore inactivation, alone or combined with other physical processes. The Weibull model described the spore inactivation by 600 MPa HPP-thermal (38, 50, 60, 75°C) and thermal (85, 90°C) processing, whereas the Lorentzian model was more appropriate for TS treatment (65, 70, 75°C). The models obtained provide a useful tool to design and predict pasteurization processes targeting B. nivea ascospores.
雪白丝衣霉是一种可以使加工水果产品变质并产生霉菌毒素的霉菌。在这项工作中，研究了高压处理（HPP，600 MPa）和功率超声（24 kHz，0.33 W/mL；TS）与 75°C 联合处理 4 周龄雪白丝衣霉子囊孢子在草莓泥中的效果，处理时间长达 30 分钟，并与单独的 75°C 热处理进行了比较。TS 和热处理可以激活霉菌子囊孢子，但 HPP-75°C 处理 20 分钟后可使孢子减少 2.0 对数级。对于 10 分钟的处理过程，HPP-75°C 比单独 85°C 更能有效减少雪白丝衣霉孢子（减少 1.4 对 0.2 对数级），这表明在较低温度下结合 HPP 比在较高温度下单独使用热更有效地灭活孢子。研究了 HPP-热处理、TS 和热处理在不同温度下对孢子的灭活作用，并对其进行了建模。所有测试的技术在较高温度下都能更快地灭活孢子，这表明温度单独或与其他物理过程结合在孢子灭活中起着重要作用。Weibull 模型描述了 600 MPa HPP-热处理（38、50、60、75°C）和热处理（85、90°C）对雪白丝衣霉子囊孢子的灭活作用，而 Lorentzian 模型更适合 TS 处理（65、70、75°C）。所获得的模型为设计和预测针对雪白丝衣霉子囊孢子的巴氏杀菌工艺提供了有用的工具。
