الفهرس 
MICROBIOLOGICAL STUDIES ON SOME FRESH JUICES IN ALEXANDRIAOnly 14 pages are availabe for public view
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Abstract
The aim of this study is examination of some juice samples, which are the most common and consumed juices sold in Alexandria City. These juice samples were sugarcane and orange juices which were collected from four different sources and regions. Five samples from each juice were collected from each shop during winter and summer in 2018.
The total fourty fresh juice samples from each juice has been conducted for several microbiological examinations, also determination and measuring of some physiochemical characteristics of these juices. The results of this study can be summarized as follows:
1. Determination of total viable count of bacteria, yeasts and molds:
Total viable count of bacterial counts were determined in sugarcane and orange juices during summer and winter seasons. The results showed that mean values of total viable bacterial counts in these juices during summer season were higher than that values during winter season. Also the overall mean of total viable bacterial counts in sugarcane juices increased about 9 folds during summer season compared with winter season. While the overall mean of bacterial counts in orange juices during summer season increased until 15 folds compared with winter season.
The results indicated no significant differences in mean values of bacterial counts between different sources of two types of juices during summer season as well as winter season. But there was significant differences between overall mean of bacterial counts in four shops during summer season compared with winter season.
Total counts of yeasts and molds were determined in each of the tested samples during summer and winter seasons. The results showed slightly in overall mean of yeasts and molds counts in both sugarcane and orange juices during summer compared with winter season. This increase was 1.4 and 1.1 folds, respectively.
The counts of bacteria, yeasts and molds in the samples of sugarcane and orange juices tested exceeded over the permitted loads recorded in the Egyptian Guideline Standard specified for juice.
2. Detection of coliform bacteria:
The presumptive test was conducted to detect the presence of coliform bacteria in both sugarcane and orange juices during summer and winter seasons. The results indicated positive samples for presence of coliform bacteria in both juices during summer and winter seasons. The results confirmed that all sugarcane juice samples collected from different shops in both seasons were contaminated with 100% of coliform bacteria. While the results showed during winter season, 20-80% of orange juice shops were contaminated with coliform bacteria but during summer season the percentage of polluted with these bacteria was 100%.