Food Microbiology ( IF 5.3 ) Pub Date : 2020-10-17 , DOI: 10.1016/j.fm.2020.103663 V. Ruiz , R. Alonso , M. Salvador , S. Condón , S. Condón-Abanto
To date, heat is still the most used technology in food preservation. The calculus of heat treatments is usually based on Bigelow observations i.e. treatment time is an exponential function of the heat treatment temperature. However, a number of researchers have reported deviations from linearity in heat inactivation curves that caused errors in the calculus. This research was designed to evaluate the variability of shoulder length among different sporulated species, the impact of treatment temperature on these shoulders and the relationship between the traditional DT value and shoulder length. The heat inactivation kinetics of five bacterial spores of importance for the food industry was evaluated. B. weihenstephanensis and B. cereus did not show shoulders and DT values calculated ranged from 0.99 to 0.23 and from 1.33 to 0.56 respectively at temperatures from 100 to 102.5 °C. On the other side B. subtilis, B. licheniformis and G. stearothermophilus showed shoulders of 1.75–0.42, 1.92–0.43 and 3.22–0.78 and DT values of 1.52–0.32, 2.12–0.59 and 2.22–0.48 respectively in the range of temperatures tested. From the results obtained it was concluded that the presence and magnitude of shoulders depended on the bacterial spore species, the longest being those on the bacterial spores which showed greatest heat resistance. It has also been proved that shoulder lengths vary with treatment temperature in the same proportion of traditional DT values, with the relationship Sl/DT being constant. Thus, an equation which included the constant Sl/DT was proposed.
中文翻译:
肩膀对不同细菌孢子热灭菌处理的结石的影响
迄今为止,加热仍然是食品保存中最常用的技术。热处理的演算通常基于Bigelow观察,即处理时间是热处理温度的指数函数。但是,许多研究人员报告了热失活曲线中线性度的偏差,这导致了微积分的误差。本研究旨在评估不同孢子形成物种之间肩长的变异性,治疗温度对这些肩长的影响以及传统D T值与肩长之间的关系。评价了对食品工业重要的五个细菌孢子的热灭活动力学。魏henstephanensis和蜡状芽孢杆菌在100至102.5°C的温度下,未显示肩部和D T值分别在0.99至0.23和1.33至0.56范围内计算。在另一侧,枯草芽孢杆菌,地衣芽孢杆菌和嗜热脂肪芽孢杆菌显示出1.75–0.42、1.92–0.43和3.22–0.78的肩膀和D T在所测试的温度范围内,该值分别为1.52-0.32、2.12-0.59和2.22-0.48。从获得的结果可以得出结论,肩的存在和大小取决于细菌的孢子种类,最长的是表现出最大耐热性的细菌的孢子。还已经证明,肩长随治疗温度的变化而按传统D T值的相同比例变化,并且关系Sl / D T是恒定的。因此,提出了一个包含常数Sl / D T的方程。