Lactobacillus helveticus CNRZ 32: Attenuation and enzymatic properties for use as a secondary culture to produce cheese

Abstract

The viability and enzymatic behaviour (proteolytic, lipolytic and glycolytic) of Lactobacillus helveticus CNRZ 32 treated at high and low temperatures were studied. The treatments were carried out with the aim of reducing its glycolytic capacity while maintaining its proteolytic and lipolytic enzyme characteristics. These characteristics are necessary for it to be potentially used as a secondary culture to accelerate cheese ripening. The culture was attenuated at 68ºC for 18 s (A) or at -18ºC x 24 h (B), and the culture viability and remaining enzymatic capacity for proteolysis, lipolysis and glycolysis in milk were compared with those of the untreated culture.
The high heat treatment of the culture achieved the best relationship between reducing the strain glycolytic capacity while maintaining the proteolytic and glycolytic capacities. The culture L. helveticus CNRZ 32 following treatment appears to be a good potential secondary culture to accelerate the cheese ripening process.