الفهرس 
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Abstract
Minimal processing of raw fruits and vegetables is intended for keeping the freshness of the product; yet supplying it in a convenient form to be ready-to-eat and ready-to-use without losing its nutritional quality is very much needed.
Fresh produce can be a vehicle for the transmission of bacterial, parasitic and viral pathogens capable of causing human illness and a number of reports refer to raw fruits and vegetables harbouring potential foodborne pathogens. The incidence of foodborne outbreaks caused by contaminated fresh fruit and vegetables has increased in recent years.
The marketing of the fruit processed in part seems to be limited due to the short validity period as a result of the speed of corruption due to increased respiration rates with and also the humidity contain is very high and the deterioration of tissue caused during processing
Therefore this work aimed to investigate the effect of minimal processing and decontamination treatment on apple, peach and grapes to maintain its quality and prolong shelf-life as possible.
The study was conducted during the 2009 season. Anna apples (Malus domestica, L.) were collected from a private farm near El-Sadat city. Florida peach (Prunus persica, L.) were brought from a private farm near Cairo-Alex desert road 75Km. Flame seedless grapes (Vitis vinifera, L.) were collected from a private farm near Cairo-Alex desert road 60 Km.
The fruits were harvested at maturity with the degree of color in the early morning. Damaged and non uniform fruits were removed and good fruits were matched by color and tissue to remove unripe and overripe fruits.
Then the fruits were put on the refrigerator for 6 hours at 4oC RH (90%-85%) as a precooling, and subdivided in to different 8 groups.
One group was packed without washing or any treatment (control treatment). Another group was washed and immersed in cold water at 4oC for 15 minutes and then left in one layer to drain in a refrigerator for 3-4 hours to remove the excessive water .Having drained, and simply packed in high density polyethylene (washing treatment).
The other six groups were treated as follows: 3 groups washed and treated with different concentration of chlorine solution (50 ppm, 100 ppm and 150 ppm). The last 3 groups washed and treated with different concentration of lactic acid buffer system (LABS) solution (0.25%, 0.50% and 1.00%).
All dipping at 4OC temperature for four minutes and then left in one layer to drain in a refrigerator for 3-4 hours in order to remove the excessive water. Having drained, then the fruits were packed in fume dishes (1/4 K.G) and wrapped with Low density polyethylene stretch (LDPE), then storage at 4 ⁰C.
Sensory (texture, taste, odor, color and appearance and overall acceptance), microbiological (counting of total psychotrophic aerobic bacteria, total yeasts and molds, total Enterobactriaceae bacteria and total of lactic acid bacteria) and chemical analysis (moisture, total soluble solids, acidity, pH, total sugars, reducing sugars, non-reducing sugars and vitamin C content) were preformed to access the quality of the tested fruits during storage at 4 ⁰C. The obtained results were statistically analyzed.
The most important results are summarized as follows:
1. The acceptance of control samples in apples were up to 35 days, in peaches up to 18 days and in grapes up to 12 days. The sample treated by double washing with cold water only was accepted in apples up to 95 days, in peaches up to 35 days and in grapes up to 12 days as the control sample.
2. Treatments that have been dipped in chlorine solution concentration (50 ppm and 100 ppm and 150 ppm) have been accepted in apples up to 120 days, in peaches up to 39 days and in grapes up to 30 days. That was the longest time to store the fresh fruits in the present study.
3. The treatments with (LABS) solution concentration (0.25%) have been accepted in apples up to 80 days, in peaches up to 35 days and in grapes up to 21 days. while the sample treated by (LABS) solution concentration (0.50%) have been accepted in apples up to 95 days, in peaches up to 35 days and in grapes up to 21 days. While the sample treated by (LABS) solution concentration (1.00%) have been accepted in apples up to 80 days, in peaches up to 30 days and in grapes up to 21 days.
4. The results of the sensory evaluation revealed that at day zero there was some different odor and taste on the treatments with high concentration of chlorine solution and high concentration of (LABS) solution, but completely disappeared in second period of the storage time of all fruits.
5. The results of the microbial analysis with all treatments showed an increase in total count of the psychotrophic aerobic bacteria, yeasts and molds, Enterobactriaceae bacteria and lactic acid bacteria but with in the permissible limits during the storage for all fruits under study.
6. The treatments with chlorine concentration at (50 ppm and 100 ppm and 150 ppm) exhibited the strongest inhibitory effect causing the least total count in all tested microorganisms in all kinds of fruits used in the study.
7. The results did not show yeast and molds or Enterobactriaceae bacteria except at the end of storage time for each treatment in apples and peaches.
8. In grapes the results showed yeast and molds count in all stages of storage, but not in the Enterobactriaceae bacteria count.
9. The results of chemical analysis showed a significant increase in total soluble solids, pH, total sugars, reducing sugars and non-reducing sugars content. However, a significantly decrease in vitamin C, acidity and moisture were detected in the all fruits but in the acceptable limits.