Universitat de Lleida, Departamento de Ciencia y Tecnología de Alimentos, XaRTA-Postharvest, Centro Agrotecnio, Rovira Roure 191, 25198 Lleida, Spain.
Universitat de Lleida, Departamento de Ciencia y Tecnología de Alimentos, XaRTA-Postharvest, Centro Agrotecnio, Rovira Roure 191, 25198 Lleida, Spain.
Int J Food Microbiol. 2020 Feb 2;314:108392. doi: 10.1016/j.ijfoodmicro.2019.108392. Epub 2019 Oct 23.
Strawberry production and exports have been increasing in Spain in recent decades. However, little information is available about their microbiological quality. Due to the growing concern about the microbial safety of these fruits, the objective of this investigation was to study the microbiological quality and the prevalence of the main foodborne pathogens on strawberries sold in Spain. Fresh (n = 152) and frozen (n = 31) samples were obtained from marketplaces and fields in 2017 and 2018. The samples were assayed for total aerobic mesophilic microorganisms (TAM), moulds and yeasts (M&Y), total coliforms (TC), Escherichia coli, Salmonella spp., Listeria monocytogenes as well as Norovirus (NoV) GI and GII. The microbiological counts ranged from <1.70 (detection limit, dl) - 5.89 log CFU/g (mean 3.78 log CFU/g) for TAM; 2.10-5.86 log CFU/g (mean 3.80 log CFU/g) for M&Y; and <0.70 (dl) - 4.91 log CFU/g (mean 2.15 log CFU/g) for TC in fresh strawberries. In frozen strawberries, the counts were <1.70 (dl) - 3.66 log CFU/g (mean 2.30 log CFU/g) for TAM; <1.70 (dl) - 2.76 log CFU/g (mean 1.82 log CFU/g) for M&Y; and <0.70(dl) - 1.74 log CFU/g (mean 0.77 log CFU/g) for TC. All the samples in this study tested negative for Salmonella spp., L. monocytogenes. E. coli and NoV GI and GII genome. A global overview of all the data was executed using Principal Component Analysis (PCA), and the results showed that the scores and loadings according to principal components 1 (PC1) and 2 (PC2) accounted for 75.9% of the total variance, allowing a distinction between fresh and frozen samples. The presence of moulds was significantly higher in the supermarket samples whereas the presence of total coliforms was significantly higher in the field samples (p < 0.05). Although pathogenic microorganisms were not found, preventative measures and prerequisites in the strawberry production chain must be considered in order to avoid possible foodborne diseases related to the microbiological quality of the fruit.
草莓在过去几十年中在西班牙的产量和出口都有所增加。然而，关于其微生物质量的信息却很少。由于人们对这些水果的微生物安全性越来越关注，因此本研究的目的是研究西班牙市售草莓的微生物质量和主要食源性致病菌的流行情况。本研究于 2017 年和 2018 年从市场和田间采集了新鲜（n=152）和冷冻（n=31）草莓样本。对样本进行了总需氧中温微生物（TAM）、霉菌和酵母（M&Y）、总大肠菌群（TC）、大肠杆菌、沙门氏菌、李斯特菌以及诺如病毒（NoV）GI 和 GII 的检测。微生物计数范围为：新鲜草莓中 TAM 为 <1.70（检测限，dl）-5.89 log CFU/g（平均值 3.78 log CFU/g）；M&Y 为 2.10-5.86 log CFU/g（平均值 3.80 log CFU/g）；TC 为 <0.70（dl）-4.91 log CFU/g（平均值 2.15 log CFU/g）。在冷冻草莓中，TAM 的计数范围为 <1.70（dl）-3.66 log CFU/g（平均值 2.30 log CFU/g）；M&Y 为 <1.70（dl）-2.76 log CFU/g（平均值 1.82 log CFU/g）；TC 为 <0.70（dl）-1.74 log CFU/g（平均值 0.77 log CFU/g）。本研究中所有样本均未检测到沙门氏菌、李斯特菌、大肠杆菌和诺如病毒 GI 和 GII 基因组。使用主成分分析（PCA）对所有数据进行了全面分析，结果表明，根据主成分 1（PC1）和 2（PC2）的得分和载荷占总方差的 75.9%，可以区分新鲜和冷冻样本。超市样本中霉菌的存在显著高于田间样本，而田间样本中总大肠菌群的存在显著高于超市样本（p<0.05）。尽管未发现致病微生物，但必须考虑草莓生产链中的预防措施和前提条件，以避免与水果微生物质量相关的食源性疾病。
