Research Unit of Cereal and Feed Technology, Department of Food Technology, Safety and Health, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium.
Laboratory of Applied Mycology (MYCOLAB), Department of Food Technology, Safety and Health, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium.
Food Sci Technol Int. 2024 Oct;30(7):636-645. doi: 10.1177/10820132231162170. Epub 2023 Mar 12.
The effect of UVC (254 nm) treatment on the mould-free shelf-life of par-baked wholemeal, rye and six-grain bread was examined. Currently, these breads are par-baked, wrapped in high-density polyethylene (HDPE)-foil and transported or stored at room temperature for a couple of days before being full-baked and sold/consumed. Generally, after five days, these breads show signs of mould spoilage. A shelf-life increase in one or more days would already offer immense economical and logistic benefits for the baker or retailer. In this study, the parameters fluence rate (irradiation intensity), fluence (UV dose), distance to the UV-lamp (DTL) and number of layers of a common wrapping HDPE-foil (20 µm) were diversified. The breads were subjected to a UVC treatment (0-2502 mJ/cm²), packed and stored at room temperature for a period of 15 days (21.5 ± 0.8 °C). Similar as for the breads, agar plates with mould spores of , and were UVC treated (0-1664 mJ/cm²) and checked daily for visible mould growth during 15 days (25 °C). showed the strongest resistance towards UVC, a fluence of 800 mJ/cm² was needed to inhibit growth during 15 days of storage, whereas for and , respectively, UV levels of 291 and 133 mJ/cm² were found sufficient. Furthermore, the shelf-life of wholemeal, rye and six-grain bread can be prolonged from 5 to 6, 8 and 9 days, respectively, using 2502 mJ/cm². The effect of higher UVC dosage on shelf-life reached a maximal level and was strongly impacted by the wide spread on data of mould-free shelf-life. The main factors influencing the potential of UV decontamination were the rough bread surface, differences in DTL, the possibility of post-contamination and UV permeability of packaging materials.
研究了 UVC（254nm）处理对未完全烘焙的全麦、黑麦和六谷面包防霉保质期的影响。目前，这些面包是半烘焙的，用高密度聚乙烯（HDPE）箔包装，在完全烘焙和销售/食用前，在室温下运输或储存几天。一般来说，五天后，这些面包就会出现霉变的迹象。保质期延长一天或更长时间，将为面包师或零售商带来巨大的经济和物流效益。在这项研究中，多样化了参数辐照强度（辐照强度）、辐照量（UV 剂量）、距 UV 灯的距离（DTL）和常见包装 HDPE 箔的层数（20μm）。将面包进行 UVC 处理（0-2502mJ/cm²），包装并在室温下储存 15 天（21.5±0.8°C）。与面包类似，含有 和 孢子的琼脂平板也接受了 UVC 处理（0-1664mJ/cm²），并在 15 天（25°C）的储存期间每天检查可见霉菌生长情况。 对 UVC 的抵抗力最强，需要 800mJ/cm²的辐照量才能抑制 15 天的储存期内的生长，而 和 则分别需要 291mJ/cm²和 133mJ/cm²的 UV 水平。此外，使用 2502mJ/cm²，全麦、黑麦和六谷面包的保质期可分别延长至 5 天、6 天、8 天和 9 天。更高的 UVC 剂量对保质期的影响达到了最大值，并且受到防霉保质期数据广泛波动的强烈影响。影响 UV 消毒潜力的主要因素是面包粗糙的表面、DTL 的差异、可能的再污染和包装材料的 UV 透过率。
