Fruit Juice especially orange (Citrus Sinensis) juice is very desirable for the consumer because of its fresh aroma and flavor, but its shelf life is less than 6 days at 4°C in best conditions during preparation, packaging, storage, handling and distribution. Microbiological quality is the bottleneck for safety and shelf life .So, this study aimed to extend the shelf life of orange juice by using green tea extracts as natural preservatives. The effect of adding green tea extracts by 0.1%, 0.2%, 0.3% to orange juice on the physical, microbial, chemical and sensory properties during storage up to 6 months were evaluated. The most important findings showed that the highest content of antioxidants, phenols and flavonoids for juice with green tea extracts (0.1%, 0.2%, and 0.3%) compared to control sample. While, green tea extracts as the best way to minimize the total number of bacteria in orange juice samples compared with control during storage period up to 6 months. Generally, it could be conducted that using of green tea water and alcoholic extracts may extend the shelf life and raise the nutritional and health value of orange juice.

t is well known that orange is the most commonly and popular fruit grown not only in Egypt but allover the world. 75% of the total production of orange are consumed at the fresh form meanwhile 25% are utilized in production of different manufactured forms such as juices, concentrates, and jam. It is also established that the wastes remained after manufacture are 10-15% of the total production. Those wastes in case of being left without any utilization are considered to be very bad source for pollution, insects, and rats especially when they were inside the factories without removal. The wastes include seeds, fibers, and peels. Thus, it was logic and naturally to study the possibility of utilization of those wastes in producing new products. Thus, this study aims to investigate the possibility of utilization of those wastes in producing important products particularly. They were found to possess significant nutrients. In the current research, osmotic dehydration of orange peel using sucrose solution at mild temperature (35ºC) was investigated. Sucrose solution (40, 50 and 60% w/w) were employed for osmotic dehydration process. Responses of weight reduction (WR), solid gain (SG), water loss (WL), color (L*, a* and b*) and texture (hardness) and sensory analysis were evaluated. It was found that sucrose concentration significantly (p < 0.05) affected the mass transfer terms during osmosis process. Moisture continent was decreased from 33.64 % in fresh peel to be 16.25% on osmotic dried peels. The obtained results revealed an increase in yellowness (b*), decrease in lightness (L*) and redness (a*) as the sucrose concentration increased. Furthermore, osmotic ally dehydrated samples were considerably softer than untreated samples. Also increasing of sucrose concentration and dehydration time gave softer tissue of dehydrated product compared with the fresh orange peel.

No abstract

No abstract

No abstract