Influence of the stretching temperature on the volatile compounds and odor intensity of high moisture mozzarella: a model study

The impact of the stretching phase on the volatile compounds (VOC) and odor intensity of high moisture mozzarella was investigated. Three trials were done using raw milk with different microbiological quality for the preparation of control and aseptic (sodium azide) cheeses at two different stretching temperatures. The SPME-GC/MS analysis showed that stretching caused a decrease of VOC from curd to cheese in the aseptic samples due to volatilization or solubilisation into the stretchwater. It was not observed in the control mozzarella due to the formation of microbial-derived VOC during the cooling phase. As to the effect of the temperature, the samples stretched at 70°C had the highest amount of VOC, except for those made from high quality milk. The formation of new VOC due to stretching remained doubtful. The control samples stretched at 70°C had the highest odor intensity, whereas stretching at 90°C resulted in a more intense odor in the aseptic cheeses.