| Broccoli (Brassica oleacea) is a perishable vegetable. Postharvest storage disorders include loss of stem firmness, yellowing, soft rots and opening of florets. As a result, it has a short shelf life after minimally processing. The objectives of this study were to: (1) use ethanol vapor to inhibit the senescence of minimally processed broccoli and maintain the green color in the florets; (2) use a fresh-holding film consisting of exopolysaccharides produced by Aureobasidium pullulan and antimicrobial protein formed by Bacillus subtilis R21-4 to curb the main microorganisms isolated from minimally processed broccoli florets stored at 4°C or 10°C; (3) result in a technological system available for extending the shelf-life of the vegetable. The following are main results:1. Exposure of 6 mL/kg ethanol vapor to minimally processed broccoli florets for 5 h produced a positive influence on the weight loss, protein content and chlorophyll content in broccoli florets stored at 4°C or 10°C. The degradation of protein and chlorophyll in the ethanol-treated broccoli florets was significantly retarded. The loss in weight of broccoli florets was reduced during the whole storage period. It was proved that the yellowing of broccoli florets treated with ethanol vapor was slowed down.2. Exposure of 6 mL/kg ethanol vapor to minimally processed broccoli florets for 5 h affected significantly the activities of POD, CAT and SOD in broccoli florets stored at 4°C or 10°C. Ethylene release and respiratory intensity of broccoli florets were clearly inhibited.3. Antimicrobial protein extracted from the supernatant of B.subtilis R21-4 with 60 % saturated ammonium sulphate was conformed to have a good activity against microorganisms isolated from minimally processed broccoli florets stored at 4°C or 10°C.4. Use of the antimicrobial film composed of pullulan and antimicrobial protein from B.subtilis R21-4 inhibited microbial spoilage occurring in minimally processed broccoli... |
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