Prediction in the Dynamics and Spoilage of <i>Shewanella putrefaciens</i> in Bigeye Tuna (<i>Thunnus obesus</i>) by Gas Sensors Stored at Different Refrigeration Temperatures

• Main Authors: Zhengkai Yi, Jing Xie
• Format: Article
• Language: English
• Published: MDPI AG 2021-09-01
• Series: Foods
• Subjects: electronic nose; <i>Shewanella putrefaciens</i>; dynamic growth; spoilage prediction; GC-MS
• Online Access: https://www.mdpi.com/2304-8158/10/9/2132

<i>Shewanella putrefaciens</i> have a faster growth rate and strong spoilage potential at low temperatures for aquatic products. This study developed a nondestructive method for predicting the kinetic growth and spoilage of <i>S. putrefaciens</i> in bigeye tuna during cold storage at 4, 7 and 10 °C by electronic nose. According to the responses of electronic nose sensor P30/2, the fitted primary kinetic models (Gompertz and logistic models) and secondary model (square root function model) were able to better simulate the dynamic growth of <i>S. putrefaciens</i>, with high R² and low RMSE values in the range of 0.96–0.99 and 0.021–0.061, respectively. A partial least squares (PLS) regression model based on both electronic nose sensor response values and electrical conductivity (EC) values predicted spoilage of <i>S. putrefaciens</i> in bigeye tuna more accurately than the PLS model based on sensor signal values only. In addition, SPME/GC-MS analysis suggested that 1-octen-3-ol, 2-nonanone, 2-heptanone, dimethyl disulfide and methylamine, N, N-dimethyl- are the key VOCs of tuna inoculated with <i>S. putrefaciens</i>.