Evaluation of the biogenic amine composition of commercial mulberry fruit wines and improving its safety and quality by selected strain

Biogenic amines (BAs) are commonly found s in fruit wine, while there are few studies on BAs in mulberry fruit wine. Hence, the BAs composition of 28 commercial mulberry fruit wine samples was investigated. Among these samples, histamine, tyramine and tryptamine were detected in 28, 27 and 24 samples, respectively. Notably, histamine content exceeded the recommended limit (10mg/L). To control the histamine content of mulberry fruit wine, two malolactic fermentation (MLF) starter cultures with high histamine degradation ability and no BAs synthesis capacity were screened, which were identified as Lactobacillus kunkeei W96 and Lactiplantibacillus plantarum W155, respectively. However, in real mulberry fruit wine, only L. plantarum W155 could control its histamine content within 10mg/L. Meanwhile, compared with L. kunkeei W96 and control strain, the mulberry fruit wine fermented by L. plantarum W155 exhibited higher levels of total flavonoids (0.89g RE/L), cyanidin-3-O-glucoside (179.69mg/L), cyanidin-3-O-rutinoside (322.36mg/L) and resveratrol (154.73mg/L) coupled with lower concentrations of methanol (48.60mg/L) and higher alcohols (372.55mg/L), which was also confirmed by correlation analysis result. Therefore, it could be concluded that L. plantarum W155 could be used as a potential MLF starter culture for the production of high-safety and high-quality mulberry fruit wine.