Effects of pre-storage treatments (using brine and vinegar) and refrigerated storage on vitamin c, β carotene, microbial load and shelf-life of red pepper (Capsicum frutescens)

Abstract

This study was carried out to determine the effects of pre-storage treatments using antimicrobial agents such as vinegar, brine and refrigeration (4 o C) on concentrations of vitamin C, β-carotene, microbial load and shelf-life of red pepper (Capsicum frutescens). The freshly harvested red pepper (C. frutescens) samples were immersed in different concentrations of brine (10% and 15%) and vinegar (0.8% and 1.5%) for about 20 minutes, air dried and kept at room temperature (28 o C). Samples without treatments were also stored at room temperature (control) and refrigerated conditions for quality and shelf life studies. The results showed that the concentrations of vitamin C and β-carotene of the fresh untreated red pepper samples decreased considerably within the storage period of 39 days. Concentrations of vitamin C and β-carotene in samples treated with 0.8% vinegar (VI), 1.5% vinegar (V2), 10% brine (B1) and 15% brine (B2) also decreased considerably within the storage period of 42 days. However, refrigerated samples (R) showed a decreased in vitamin C concentration but an increase in β-carotene concentration within the storage period of within 48 days. The various pre-storage treatments caused significant decreases (P<0.05) in the microbial load (total coliforms and total plate counts) on day 0 (immediately after treatment) but increased gradually within the storage period except refrigeration which kept the microbial load stable within the storage period. It can be concluded from the results that essential nutrients (Vitamin C and β-carotene) were favourably maintained in the refrigerated conditions as compared to the other pre-storage treatments