Effect of different isolation sources of Lactococcus lactis subsp. lactis on volatile metabolites in fermented milk

Xia Yu; Yaru Sun; Xin Shen; Weicheng Li; Hongyu Cai; Shuai Guo; Zhihong Sun

doi:10.1016/j.fochx.2024.101224

Effect of different isolation sources of Lactococcus lactis subsp. lactis on volatile metabolites in fermented milk

Food Chem X. 2024 Feb 12:21:101224. doi: 10.1016/j.fochx.2024.101224. eCollection 2024 Mar 30.

Authors

Xia Yu¹, Yaru Sun¹, Xin Shen¹, Weicheng Li¹, Hongyu Cai¹, Shuai Guo¹, Zhihong Sun¹

Affiliation

¹ Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, China; Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot, China; Inner Mongolia Key Laboratory of Dairy Biotechnology and Engineering, Inner Mongolia Agricultural University, Hohhot 010018, China.

Abstract

Lactococcus lactis subsp. lactis (L. lactis subsp. lactis) is a commonly used starter cultures in fermented dairy products, contributing distinct flavor and texture characteristics with high application value. However, the strains from different isolates have different contributions to milk fermentation. Therefore, this study aimed to investigate the influence of L. lactis subsp. lactis isolated from various sources on the volatile metabolites present in fermented milk. In this study, L. lactis subsp. lactis from different isolation sources (yogurt, koumiss and goat yogurt) was utilized as a starter culture for fermentation. The volatile metabolites of fermented milk were subsequently analyzed by headspace solid phase microextraction gas chromatography-mass spectrography (HS-SPME-GC-MS). The results indicated significant differences in the structure and abundance of volatile metabolites in fermented milk produced with different isolates (R²Y = 0.96, Q² = 0.88). Notably, the strains isolated from goat yogurt appeared to enhance the accumulation of ketones (goat yogurt vs yogurt milk: 50 %; goat yogur vs koumiss: 27.3 %)and aldehydes (goat yogurt vs yogurt milk: 21.4 %; goat yogurt vs koumiss: 54.5 %) in fermented milk than strains isolated from koumiss and yogurt milk. It significantly promoted the production of 8 flavor substances (1 substance with OAV ≥ 1 and 6 substances with OAV > 0.1) and enhanced the biosynthesis of valine, leucine, and isoleucine. This study provides valuable insights for the application of Lactococcus lactis subsp. lactis isolated from different sources in fermented dairy production and screening of potential starter cultures.

Keywords: 2,3-Butanedione (PubChem CID: 650); 2-Heptanone (PubChem CID: 8051); 2-Nonanone (PubChem CID: 13187); 2-Undecanone (PubChem CID: 8163); 3-Methyl-1-butanol (PubChem CID: 31260); Acetic acid (PubChem CID: 176); Acetoin (PubChem CID: 179); Different naturally fermented milk isolates; Fermented milk; Heptanal (PubChem CID: 8130); Hexanal (PubChem CID: 6184); Lactococcus lactis subsp. lactis; Nonanal (PubChem CID: 31289); Volatile metabolites.