Strains of Lactobacillus curvatus, Leuconostoc mesenteroides, Lactobacillus plantarum and Weissella confusa were identified from raw red and yellowpeppers (RYPs) by partial 16S rRNA gene sequence and subjected to typing by Random Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR) analysis. L. plantarum PE21, L. curvatus PE4 and W. confusa PE36 were selected based on the kinetics of growth and acidification, and used as the autochthonous mixed starter for the fermentation of RYPs. A protocol which included blanching at 85 °C for 2 min, fermentation at 35 °C for 15 h in brine (1%, w/v), and heat treatment at 85 °C for 15 min, followed by storage at roomtemperature for 30 days with and without sunflower seeds oil was set up. Unstarted RYPs subjected to the same treatments were used as the control. Cell numbers of autochthonousstarter in the RYPs were ca. 1000 times higher than presumptive lactic acid bacteria in unstarted RYPs. As shown by RAPD-PCR analysis, all three autochthonous strains persisted during processing and storage. Presumptive lactic acid bacteria found in started RYPs progressively decreased during storage, leading to a microbiota mainly consisting of autochthonousstarters. Started RYPs showed rapid decrease of pH (< 3.7), marked consumption of fermentable carbohydrates, and inhibition of total enterobacteria and yeasts. Unstarted RYPs were subjected to slight acidification (pH ca. 4.87) and considerable contamination by total enterobacteria and yeasts throughout storage. After 30 days of storage, started RYPs had significantly (P < 0.05) higher firmness and colour indexes with respect to unstarted RYPs. The microbial and sensory features of started RYPs stored with sunflower seeds oil were almost similar to those of RYPs stored without suspending liquid.
Use of autochthonous starters to ferment red and yellow peppers (Capsicum annum L.) to be stored at room temperature / DI CAGNO, Raffaella; Surico, R. F.; Minervini, G.; DE ANGELIS, Maria; Rizzello, CARLO GIUSEPPE; Gobbetti, Marco. - 130:(2009), pp. 108-116. [10.1016/j.ijfoodmicro.2009.01.019]
Use of autochthonous starters to ferment red and yellow peppers (Capsicum annum L.) to be stored at room temperature
RIZZELLO, CARLO GIUSEPPE;
2009
Abstract
Strains of Lactobacillus curvatus, Leuconostoc mesenteroides, Lactobacillus plantarum and Weissella confusa were identified from raw red and yellowpeppers (RYPs) by partial 16S rRNA gene sequence and subjected to typing by Random Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR) analysis. L. plantarum PE21, L. curvatus PE4 and W. confusa PE36 were selected based on the kinetics of growth and acidification, and used as the autochthonous mixed starter for the fermentation of RYPs. A protocol which included blanching at 85 °C for 2 min, fermentation at 35 °C for 15 h in brine (1%, w/v), and heat treatment at 85 °C for 15 min, followed by storage at roomtemperature for 30 days with and without sunflower seeds oil was set up. Unstarted RYPs subjected to the same treatments were used as the control. Cell numbers of autochthonousstarter in the RYPs were ca. 1000 times higher than presumptive lactic acid bacteria in unstarted RYPs. As shown by RAPD-PCR analysis, all three autochthonous strains persisted during processing and storage. Presumptive lactic acid bacteria found in started RYPs progressively decreased during storage, leading to a microbiota mainly consisting of autochthonousstarters. Started RYPs showed rapid decrease of pH (< 3.7), marked consumption of fermentable carbohydrates, and inhibition of total enterobacteria and yeasts. Unstarted RYPs were subjected to slight acidification (pH ca. 4.87) and considerable contamination by total enterobacteria and yeasts throughout storage. After 30 days of storage, started RYPs had significantly (P < 0.05) higher firmness and colour indexes with respect to unstarted RYPs. The microbial and sensory features of started RYPs stored with sunflower seeds oil were almost similar to those of RYPs stored without suspending liquid.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.