Summary: | 碩士 === 大仁科技大學 === 食品科技研究所 === 106 === Abstract
Student ID: M05160001
Title of Thesis: Survey of hygienic qualities on ready to eat salads
Total Pages: 58
Name of Institute: Tajen University
Name of Department: Department of Food Science and Technology
Date of Graduation: Jul,2018 Degree Conferred: Master
Name of Student:Yi-Chen Jao Adviser:Dr.Tao-yi Zeng
Abstract:
In recent years, not only health awareness have risen up, but also the government set many policies of promotion concerning vegetable and fruit diets, the market demanding for fresh cut fruits and vegetables has gradually grown up and become more common. Since the cut fruits and vegetables is the kind of light processing products which have not been heated during processing, cleaning is the only method which can control the existence of microorganisms. Microbial contamination may caused from many possibilities, including the farm environment, post-harvest treatment, and the processing. During the processing process, the plant tissues might be damaged, which give the microorganisms chances to contaminate the products. This kind of products may cause many risks due to pathogen contamination, short shelf life and the difficulties to control the sanitary conditions. Food poisoning data shows that the cause of food poisoning identified by the cause of the disease is mainly caused by micro-organisms. The weather in Taiwan is subtropical, which is hot and humid especially in summer. This kind of climate pattern is more suitable for the growth and reproduction of microorganisms. The cases of food-borne pathogens cause food poisoning themoist is the most common one.
In this study, 100 samples were collected from all stations in Taiwan in 2016 to investigate whether the types of fruits and vegetables, sampling area, package type, and sales location caused microbiological quality problems or not. The results showed that there was a significant difference between the number of viable cells (p=0.003) and the test results of coliform bacteria (p=0.008) for different types of fruits and vegetables. Among them, the pollution-free rate of mycelium count was the highest percentage in fruits (54.29%), followed by bud root vegetables (40.63%) and leaf vegetables (15.15%). The passing rate of fruits was significantly higher than the rate of leaf vegetables (p< 0.05). The passing rate of coliform was the highest one in fruits (51.43%), followed by bud root vegetables (50.00%), and the leaf vegetables (18.18%) was the lowest. The passing rate of fruits and leaf vegetables was significantly higher than that of leaf vegetables (p< 0.05). There were significant differences in the number of fresh fruit and vegetables (p=0.000), coliform (p=0.000), and Staphylococcus aureus (p=0.002) in different selling locations. The pollution-free rate of the number of tested bacteria was the highest in supermarkets (63.64%), followed by restaurants (43.75%) with the minimum rate of 5.71%.
On the other hand, the passing rates of aerobic plate count, coliform and Staphylococcus aureus in the general stores and supermarkets was significantly higher than that in restaurants (p=0.000), the results indicated that the fresh cut fruits and vegetables obtained from the restaurants had a higher risk of microbial contamination. There were no significant differences in the results of microbiological quality inspections of fresh cut fruits and vegetables sampled in the north, central and southern parts of Taiwan, which representing the sampling area did not affect the microbiological quality of fresh cut fruits and vegetables (p< 0.05). The results of microbiological hygiene inspections of fresh cut fruits and vegetables in different packaging types showed that packaging types has a significant effect of aerobic plate count (p=0.008), coliform (p=0.04) and Staphylococcus aureus (p=0.004).
The pollution-free rate of aerobic plate count, coliform and Staphylococcus aureus for the fruits and vegetables which were complete packaged were significantly higher than which were incomplete packaged. The result represents that the complete packaging can effectively improve the microbiological quality of fresh cut fruits and vegetables.
Keywords:Ready to eat salads, Commercial survey, Hygienic indicator bacteria
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