Summary: | 碩士 === 國立臺灣海洋大學 === 食品科學系 === 105 === Recently, temperature management in the cold chains has receive attention. Broken cold chain caused serious problem to food safety and quality. In Taiwan, an increasing need for chilled and frozen food home delivery services has been observed because of growing demand for those products by consumers. This study aimed to evaluate temperature requirements in home delivery, by considering food safety risks to chilled foods and quality change to frozen foods. While quantitative microbial risk assessments of Vibrio parahaemolyticus in shrimp was performed to assess the food safety, a kinetic model was employed to describe the quality change in frozen white shrimp. The results showed the mean probability risk of illness due to ingestion of pathogenic Vibrio parahaemolyticus in raw shrimp distributed under chilled temperature was estimated to be 5.40 × 10-6 (Scenario I). Reducing the maximum temperature fluctuation to 15°C and 7 °C during transportation (Scenario II and III) could reduce the probability risk of becoming ill to 5.32 × 10-6 and 4.99 × 10-6 in chilled shrimp, respectively. Moreover, reducing the range of temperature fluctuation during transportation in Scenario IV, V, VI, and VII also reduced the probability risk of illness. Through simulation, a lower probability risk of illness was yielded in Scenario VII with temperature range of 7 ± 4°C. In frozen shrimp, abusive temperature during transportation induced the percentage loss of remaining shelf life higher than 90% (Scenario I). Reducing maximum temperature fluctuation as mentioned in Scenario II and III were found has a little impact on predicted remaining shelf life. Among the Scenario IV, V, VI, and VII, a better preservation on frozen shrimp quality was obtained in Scenario VII by reducing the range of temperature fluctuation to -18 ± 4°C. Therefore, reducing the maximum temperature in Scenario III and narrowing the temperature range in Scenario VII are recommended as an integral part of temperature management control in home delivery cold chain, given fact that these scenarios could lower the probability risk of illness in chilled shrimp and preserve the remaining shelf life of frozen shrimp. Furthermore, a sufficient equipment to produce a required temperature, temperature control during distribution, personnel training, and simple measurement in post-harvest level are suggested for both chilled and frozen transportation chain to ensure the safety and increase the shelf life of shrimp. These findings could help food authorities determine temperature management policies to prevent broken cold chains and reduce food safety risks.
|