Bourdoux Siméon, Li Dan, Rajkovic Andreja, Devlieghere Frank, Uyttendaele Mieke
Laboratory of Food Microbiology and Food Preservation, Dept. of Food Safety and Food Quality, Faculty of Bioscience Engineering, Ghent Univ, Coupure Links 653, 9000, Ghent, Belgium.
Compr Rev Food Sci Food Saf. 2016 Nov;15(6):1056-1066. doi: 10.1111/1541-4337.12224. Epub 2016 Sep 7.
Dried fruits, vegetables, herbs, and spices are produced in and sourced from many countries worldwide, but they have been increasingly reported to be involved in outbreaks and alerts due to the presence of foodborne pathogens such as Salmonella. These dried products are mainly produced by solar drying and conventional air drying, but a wide range of drying technologies are available. From a technological point of view the general trend is to optimize and standardize the drying process to ensure high-quality products to be offered. Drying technologies are mainly evaluated for their performance to reduce water activity at low energy cost while maintaining good sensorial quality of the dried product. However, as low water activity foods are increasingly recognized to support microbial survival and dried products are often consumed as they are, or are used as ingredients in many ready-to-eat foods, there is increasing attention to the microbiological quality and safety aspects of these products. This review presents traditional and emerging technologies to dry fruits, vegetables, herbs, and spices and discusses their potential to inactivate bacteria and viruses throughout the drying process. Overall, the microbial inactivation effect of the presented technologies has not yet been thoroughly assessed, even for traditional methods like solar drying, conventional air drying, or freeze-drying. Emerging technologies such as dielectric (assisted) drying and low-pressure superheated steam drying have been shown to reduce microbial populations; however, the number of studies is still low. Very few studies have focused on viral inactivation during drying processes.
干制水果、蔬菜、药草和香料在全球许多国家生产并采购，但越来越多的报告显示，由于存在诸如沙门氏菌等食源性病原体，它们与疫情爆发和警报有关。这些干制品主要通过太阳能干燥和传统空气干燥生产，但有多种干燥技术可供选择。从技术角度来看，总体趋势是优化和规范干燥过程，以确保提供高质量的产品。干燥技术主要根据其在低能源成本下降低水分活度同时保持干制品良好感官品质的性能来评估。然而，由于低水分活度食品越来越被认为能支持微生物存活，而且干制品通常直接食用，或用作许多即食食品的原料，因此人们越来越关注这些产品的微生物质量和安全方面。本综述介绍了用于干燥水果、蔬菜、药草和香料的传统技术和新兴技术，并讨论了它们在整个干燥过程中灭活细菌和病毒的潜力。总体而言，即使对于太阳能干燥、传统空气干燥或冷冻干燥等传统方法，所介绍技术的微生物灭活效果尚未得到充分评估。介电（辅助）干燥和低压过热蒸汽干燥等新兴技术已被证明能减少微生物数量；然而，研究数量仍然很少。很少有研究关注干燥过程中的病毒灭活。
