关键词: 乳酸菌, 接种发酵, 大头菜, 品质, 硬度, 果胶

Abstract:

The effect of fermentation with a mixed starter culture of lactic acid bacteria on sensory, physicochemical
and microbial properties of kohlrabi pieces was examined, and the correlation between the hardness and pectin content
of fermented kohlrabi was discussed. Results showed that lactic acid bacterial fermentation had a significant impact on
sensory and microbial properties of kohlrabi as indicated by improved aroma and taste and effectively reduced coliform
group. The fermentation also had a significant influence on the contents of total acid and nitrite, chewiness, viscosity,
the contents of reducing sugar, amino acid nitrogen and VC, hardness and pectin content in kohlrabi, but exerted only
marginal effects on color, elasticity and cohesiveness. Moreover, after fermentation for 3 months, the sensory evaluation
score of the fermented product was 94.0, and nitrite content and the number of coliform bacteria were 1.43 mg/kg and
< 30 MPN/100 g, respectively. This strategy could significantly shorten the production cycle and improve the product
quality and safety. During fermentation, the hardness was significantly positively correlated with protopectin, and negatively
correlated with water-soluble pectin, indicating that the mechanism for the changes in textural properties became more
diverse and complicated.

Key words: lactic acid bacteria, inoculated fermentation, kohlrabi, quality, hardness, pectin