Prolonging the Shelf life of Orange Juice Via Lemongrass Extracts

Document Type : Original Article

Authors

1 Dept. Hort. Crops Res., Food Technol .Res. Inst., Agric. Res. Cent., Giza, Egypt.

2 Dept. Food and Dairy Sci. and Techol., Fac. Environ. Agric. Sci., Arish Univ., Egypt.

Abstract

Freshly squeezed, unpasteurized orange juice is very desirable for the consumer because of its fresh aroma and flavor, but the shelf life is less than 6 days at 4 °C. Microbiological quality is the bottleneck for safety and shelf life. So,this study aimed to extend the shelf life of orange juice by using lemongrass extracts as natural preservatives. The effect of adding lemongrass extracts of 0.1, 0.2, and 0.3% to orange juice on the physicochemical, microbial, and sensory properties during storage up to 6 months were studied. The most important findings showed that the highest content of antioxidants, phenols, and flavonoids were found in orange juice plus (0.3%) lemongrass aqueous and ethanolic extracts for treatments A3 and B3, compared to all treatments. As a result, orange juice fortified with lemongrass extracts could be considered a good source of antioxidant activity as a free radical scavenger and extending the product's shelf life. Furthermore, lemongrass extracts had the best way to minimize the total number of bacteria in juice samples compared with controls during the storage up to 6 months. Fractionation of phenolic and flavonoid compounds of dried and extracted lemongrass by HPLC method showed that pyrogallol was the predominant phenolic compound of lemongrass powder, aqueous, and ethanolic extracts, while rutin was the predominant flavonoid compound. Results indicated that orange juice fortified with lemongrass aqueous extracts was more favorable than that fortified with ethanolic extracts or with sodium benzoates. Generally, it could be concluded that using lemongrass aqueous and ethanolic extracts extended the shelf life and raised the nutritional and health value of orange juice.

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