AKTIVITAS ANTIOKSIDAN DAN ANTIBAKTERI EKSTRAK KULIT JERUK MANIS (Citrus sinensis) DAN APLIKASINYA SEBAGAI PENGAWET PANGAN

Abstract

Microbial contamination may cause food poisoning and a decrease in food quality. Preservatives such as Citrus senensis sweet orange peel waste can be used to extend the shelf life of food. The purpose of this study was to measure the potential antioxidant and antibacterial activity of orange peel extract and its application to improve the quality of meatballs, wet noodles, and tofu. Meatballs, wet noodles, and tofu were soaked with the extract for 90 minutes prior to storage at room temperature (28±2°C) for 4 days. The results showed that the inhibition zone of the extract using disc diffusion assay was 17.67±0.58 mm against Escherichia coli, 16±1 mm against Staphylococcus aureus, and 12.67±1.15 mm against Salmonella Typhi. Sweet orange peel extract had an antioxidant activity of 66.41% with total phenol of 2,656.48±55.46 mg GAE/100g. The extract was able to reduce total bacteria between 0.5 and 1.0 log CFU/g in meatballs, wet noodles and tofu. The application of the extract on meatballs, wet noodles and tofu preserved aroma and color attribute until 4^th day of storage at room temperature (28±2°C). Decrease of texture attributes were observed starting from 3^rd day of storage at room temperature (28±2°C).