Escuela de Tecnología de Alimentos, Universidad de Costa Rica (UCR), Ciudad Universitaria Rodrigo Facio, CP 11501-2060, San José, Costa Rica.
Department of Food Science, Cornell University, 665 West North Street, Geneva, New York 14456, USA.
J Food Prot. 2019 Oct;82(10):1736-1743. doi: 10.4315/0362-028X.JFP-19-071.
Consumption of spicy foods and hot sauces is currently a popular trend worldwide. Shelf-stable acidified sauces are commonly hot-filled to ensure commercial sterility, but cold-fill-hold processes might also be suitable if microbial safety and stability are ensured. For this study, model acidified hot pepper sauces were developed and characterized. The effects of sauce pH and of two different organic acids on the survival of and isolated from contaminated commercial hot sauces and on pathogenic O157:H7, and were assessed. Full factorial designs with three levels for pH (3.2, 3.5, and 3.9) and two for organic acid (citric and acetic) were used to determine the effects of these factors and their interactions on the survival of the microorganisms. Commercially sterile sauces were independently inoculated and kept at ambient temperature. Microbial counts were determined at different sampling times, depending on the treatment evaluated. Sauces acidified to pH 3.2 with citric or acetic acid were inoculated with cocktails of five strains or serotypes of the three pertinent pathogens, and inactivation curves were determined. Trials were performed in triplicate. A greater than 5-log reduction of and was achieved in less than 6 h in sauces adjusted to pH 3.2 with acetic acid. Greater than 5-log reductions of pathogenic bacteria were achieved 0.5 h after inoculation in sauces acidified to pH 3.2 with acetic acid. In contrast, at least 48 h was required to guarantee the same inactivation for the most tolerant pathogen when citric acid was used. Thus, a cold-fill-hold process may be a suitable alternative for acidified hot pepper sauces. Based on survival of the microorganisms evaluated in this study, microbial safety and stability can be achieved by adjusting the pH to 3.2 or less by the addition of acetic acid.
食用辛辣食物和辣椒酱目前在全球范围内是一种流行趋势。货架稳定酸化酱通常采用热填充以确保商业无菌，但如果确保微生物安全性和稳定性，冷填充-保持过程也可能适用。在本研究中，开发并表征了模型酸化辣椒酱。评估了酱汁 pH 值和两种不同有机酸对从受污染商业辣椒酱中分离出来的 和 以及食源性致病菌 O157:H7、 和 的生存能力的影响。采用 pH 值（3.2、3.5 和 3.9）和两种有机酸（柠檬酸和乙酸）的三水平完全因子设计来确定这些因素及其相互作用对微生物存活的影响。商业无菌酱汁被独立接种并在环境温度下保存。根据评估的处理方式，在不同的采样时间点测定微生物计数。将酸化至 pH 3.2 的酱汁用柠檬酸或乙酸接种含有三种相关病原体的五个菌株或血清型的鸡尾酒，并确定失活动力学曲线。试验重复进行了三次。用柠檬酸酸化至 pH 3.2 的酱汁中，在不到 6 小时内即可实现 和 的 5 个对数减少，而用乙酸酸化至 pH 3.2 的酱汁中，在接种后 0.5 小时内即可实现致病菌的 5 个对数减少。相比之下，在用柠檬酸时，至少需要 48 小时才能保证最耐受的病原体达到相同的失活效果。因此，冷填充-保持过程可能是酸化辣椒酱的一种合适替代方法。基于本研究中评估的微生物存活情况，通过将 pH 值调整至 3.2 或更低并添加乙酸，可以实现微生物安全性和稳定性。
