Non-aminobiogenic starter cultures in a model system of cucumber fermentation

Abstract

Liquid chromatography–mass spectrometry and 16S rDNA amplicon sequencing were applied for assessing the biogenic amine (BA) content and bacterial community profile in a model system of cucumber fermentation. The non-aminobiogenic strains Lacticaseibacillus casei KKP 3272 and Pediococcus pentosaceus KKP 3273 were used individually as starter cultures. The Biogenic Amine Index (BAI) was effectively reduced by both tested strains compared with that in the spontaneously fermented samples. After 6 months of storage, BAI was reduced by 78.18 and 90.12% following fermentation by L. casei and P. pentosaceus, respectively. Histamine and putrescine were reduced by over 90% regardless of the starter culture used, while P. pentosaceus KKP 3273 was more effective for reducing tyramine and cadaverine levels (96% and 51% decrease, respectively). Detailed analysis revealed that the bacterial community profile of the samples depended on the strain applied and number of inoculated cells. Addition of 107 CFU⋅mL−1P. pentosaceus KKP 3273 or L. casei KKP 3272 resulted in their predominance in the samples after storage (93.03% and 78.62%, respectively). In spontaneously fermented samples, Enterobacter (35.21%), Lactobacillus (22.41%), and Pediococcus (20.40%) prevailed. The application of an appropriate amount of well-characterised starter culture can effectively prevent the formation of high amounts of BAs and provide a safer product.