Combined Effect of Pretreatments and Packaging Materials on Quality Retention in Dried Cabbage (Brassica oleraceae var. capitata L.)

Abstract

Cabbage (Brassica oleracea L. var. capitata) is one of the most important vegetables grown worldwide and is store house of vitamins such as β-carotene, ascorbic acid, folic acid and riboflavin. The presence of high moisture content in leafy vegetables makes them more perishable as well as seasonal availability limits their availability all round the year. Drying of cabbage leaves with suitable additive treatment during blanching can retain good sensory and rehydration qualities during storage. Blanching treatment with additive treatment at 100 °C for 5 min resulted in minimum loss of 13.4% and 15.4% of chlorophyll a and chlorophyll b content as compared to 54.2% and 84.6% of chlorophyll a and chlorophyll b, respectively without additive treatment for blanching of cabbage leaves. The chemical additive in boiling water, microwave blanching treatment and chemical additive with microwave treatment for 2 and 4 min had significant effect (P < 0.05) on losses of β-carotene in cabbage leaves. The maximum increase (101.1%) of moisture content in dried cabbage leaves was obtained in PB while minimum increase (65.2%) was attained in PP pouches after 60 days of storage. The values for L*, a* and b* coordinates after drying were 55.12, − 6.86 and 14.87, respectively. Fresh cabbage leaves contained 621.1 mg GAE/100 g dm TPC which increased to 724.5 mg GAE/100 g dm after drying of cabbage leaves. However, TPC decreased during storage for 60 days in different packaging materials. The minimum decrease (54.9%) in antioxidant activity of dried cabbage leaves was obtained in PP pouches, whereas the decrease in antioxidant activity was 88.7% and 81.6% after 60 days of storage in PB and GB, respectively. There had been a strong relationship (r2 = 0.94) of phenolic content and antioxidant activity in dried cabbage leaves. Dried cabbage leaves packaged in polypropylene pouches exhibited maximum sensory attributes and nutritional quality while cabbage leaves packaged in plastic bottles had minimum sensory and nutritional quality after 60 days of ambient storage.