Influence of a bacteriocin-producing lactic culture on the volatile compounds, odour and aroma of Hispánico cheese

The effect of milk inoculation with a bacteriocin-producing lactic culture on Hispánico cheese volatile compounds, odour and aroma was investigated in duplicate experiments, each consisting of two 50-L vats. Milk for experimental cheese was inoculated with 0.5% Lactococcus lactis subsp. lactis INIA 415, a bacteriocin-producing (Bac+) strain harbouring the structural genes of nisin Z and lacticin 481, 0.5% L. lactis subsp. lactis INIA 415-2, a Bac− mutant, and 2% TA052, a commercial Streptococcus thermophilus culture. Lactic cultures for control cheese were 1% L. lactis subsp. lactis INIA 415-2 and 2% TA052. Milk inoculation with bacteriocin-producing culture enhanced the formation of hexanal, 2-methyl-1-propanol, 3-methyl-1-butanol, acetone, 2-pentanone, 2-hexanone and 2-heptanone, but decreased the formation of acetaldehyde, ethanol, 3-methyl-3-buten-1-ol, 3-methyl-2-buten-1-ol, ethyl acetate, ethyl butanoate, ethyl hexanoate, 2-butanone, 2,3-butanedione, 2,3-pentanedione and 3-hydroxy-2-butanone. Experimental cheese received higher scores than control cheese for the odour descriptor “clean cheese” and for the aroma descriptor “sheepy”, but quality and intensity of odour and aroma were not significantly influenced by milk inoculation with the bacteriocin-producing culture.