Effect of co-inoculation and sequential inoculation of Lactobacillus fermentum and Pichia kluyveri on pork hydrolysates fermentation

This is the first study on exploiting a LAB - Lactobacillus fermentum PCC and a yeast Pichia kluyveri (FrootZen) as starter cultures in meat-based sauce fermentation. An apparent antagonistic relationship was observed between these two cultures. P. kluyveri proliferated with an increased cell count of only 1.14 log CFU/mL and dropped to the original level (approx. 5.8 log CFU/mL), while the LAB growth was stimulated by increasing the cell count by 1.67 log CFU/mL in simultaneous inoculation. More pleasant fruity aromatic esters such as hexyl acetate and 2-phenylethyl acetate were detected in the sequential inoculation, while more acetic acid was detected in the simultaneous inoculation. However, there were no significant differences (P ≥ 0.05) in the glucose usage, production of organic acids, and amino acids in the fermented pork hydrolysates between these two inoculation methods.