PDF(Pubmed)
Abstract：
Fresh-cut radishes are susceptible to quality loss and microbial contamination during storage, resulting in a short shelf life. This study investigated the effects of photodynamic technology (PDT) on fresh-cut radishes stored at 4 °C for 10 d and developed appropriate models to predict the shelf life. Results showed that curcumin-mediated PDT maintained sensory acceptability, color, and firmness, decreased weight loss, and increased ascorbic acid and total phenolics of samples by inactivating polyphenol oxidase and peroxidase, resulting in improved antioxidant capacity and quality. The total bacteria count in samples was significantly (p < 0.05) reduced by 2.01 log CFU g-1 after PDT and their shelf life was extended by 6 d compared to the control. To accurately predict the shelf life, the kinetic models based on microbial growth were established, while weight loss, b* value, firmness, and ascorbic acid were selected as representative attributes for developing quality-based prediction models through correlation analysis. Modeling results showed prediction models based on ascorbic acid best fitted PDT-treated samples, while the modified Gompertz model based on bacteria growth was the best for control and samples treated by sodium hypochlorite. This study suggests that PDT is promising in extending the shelf life of fresh-cut radishes, and using critical indexes to establish the prediction model can provide a more reliable shelf-life estimation.
摘要：
鲜切萝卜在储存过程中易受品质损失和微生物污染,导致保质期短。这项研究调查了光动力技术（PDT）对在4°C下储存10d的鲜切萝卜的影响，并开发了适当的模型来预测保质期。结果表明，姜黄素介导的PDT维持感官可接受性，颜色,和坚定，体重减轻,通过使多酚氧化酶和过氧化物酶失活来增加样品的抗坏血酸和总酚，从而提高抗氧化能力和质量。PDT后样品中的总细菌计数显著(p<0.05)减少了2.01logCFUg-1,并且与对照相比,它们的保质期延长了6天。为了准确预测保质期，建立了基于微生物生长的动力学模型，在减肥的同时，b*值，坚定,通过相关性分析，选择抗坏血酸作为开发基于质量的预测模型的代表性属性。建模结果表明，基于抗坏血酸的预测模型最适合PDT处理的样品，而基于细菌生长的改进的Gompertz模型对于对照和次氯酸钠处理的样品是最好的。这项研究表明，PDT有望延长鲜切萝卜的保质期，用关键指标建立预测模型可以提供更可靠的货架期估计。
