Department of Chemical Engineering, Gebze Technical University, 41400 Gebze, Kocaeli, Turkey.
Department of Chemical Engineering, Gebze Technical University, 41400 Gebze, Kocaeli, Turkey.
Int J Food Microbiol. 2018 Feb 2;266:274-281. doi: 10.1016/j.ijfoodmicro.2017.12.017. Epub 2017 Dec 18.
The growth data of Pseudomonas spp. on sliced mushrooms (Agaricus bisporus) stored between 4 and 28°C were obtained and fitted to three different primary models, known as the modified Gompertz, logistic and Baranyi models. The goodness of fit of these models was compared by considering the mean squared error (MSE) and the coefficient of determination for nonlinear regression (pseudo-R). The Baranyi model yielded the lowest MSE and highest pseudo-R values. Therefore, the Baranyi model was selected as the best primary model. Maximum specific growth rate (r) and lag phase duration (λ) obtained from the Baranyi model were fitted to secondary models namely, the Ratkowsky and Arrhenius models. High pseudo-R and low MSE values indicated that the Arrhenius model has a high goodness of fit to determine the effect of temperature on r. Observed number of Pseudomonas spp. on sliced mushrooms from independent experiments was compared with the predicted number of Pseudomonas spp. with the models used by considering the B and A values. The B and A values were found to be 0.974 and 1.036, respectively. The correlation between the observed and predicted number of Pseudomonas spp. was high. Mushroom spoilage was simulated as a function of temperature with the models used. The models used for Pseudomonas spp. growth can provide a fast and cost-effective alternative to traditional microbiological techniques to determine the effect of storage temperature on product shelf-life. The models can be used to evaluate the growth behaviour of Pseudomonas spp. on sliced mushroom, set limits for the quantitative detection of the microbial spoilage and assess product shelf-life.
获得了在 4 至 28°C 之间储存的切片蘑菇（双孢蘑菇）上假单胞菌生长数据，并将其拟合到三种不同的基本模型中，即修正的 Gompertz、逻辑和 Baranyi 模型。通过考虑均方误差 (MSE) 和非线性回归的确定系数 (伪 R) 来比较这些模型的拟合优度。Baranyi 模型的 MSE 和伪 R 值最低。因此，选择 Baranyi 模型作为最佳基本模型。从 Baranyi 模型获得的最大比生长速率 (r) 和滞后期持续时间 (λ) 拟合到二次模型，即 Ratkowsky 和 Arrhenius 模型。高伪 R 和低 MSE 值表明 Arrhenius 模型具有很好的拟合度，可以确定温度对 r 的影响。通过考虑 B 和 A 值，将独立实验中观察到的切片蘑菇上假单胞菌数量与使用模型预测的假单胞菌数量进行比较。发现 B 和 A 值分别为 0.974 和 1.036。观察到的和预测的假单胞菌数量之间具有高度相关性。使用模型模拟了蘑菇变质与温度的关系。用于假单胞菌生长的模型可以为传统微生物技术提供快速且具有成本效益的替代方法，以确定储存温度对产品保质期的影响。这些模型可用于评估假单胞菌在切片蘑菇上的生长行为，为微生物腐败的定量检测设定限制，并评估产品的保质期。
