Variability of volatile organic compounds during the manufacture of Swiss-typecheese using selected ion flow tube mass spectrometry

摘要

The determination of the volatile organic compound (VOC) profiles in Swiss cheese samples from four different stages of manufacture was achieved using static headspace sampling with selected ion flow tube-mass spectrometry (SIFT-MS). Ten cheese samples from two different batches of Swiss cheese manufactured from a single factory were obtained. The stages included: out-of-press, end of pre-cool, end of warm room and at time of cutting. Multivariate stage-level classification using SIMCA showed significant discrimination of VOC profiles among the four manufacturing stages. This suggests a varied VOC profile/behavior at each stage of manufacture. The VOC profile of samples from the end of warm room stage was highly discriminatory, relative to other stages. Key discriminating VOCs and the highest VOC concentration at each stage were identified. Significant variability of VOC profiles among the five vats within the same make-date and stage of manufacture was also observed. There was an increased inhomogeneity in VOC profiles between vats towards the final stages of manufacture. Variabilities were most probably related to varied fermentation activities, changes in microflora, biochemical factors, and physical and environmental conditions. These findingsprovide in-depth knowledge on the biochemistry and microbiology associated with VOC production. These would be beneficial, especially for effective/ efficient control in bringing consistency in texture, flavor and aroma of Swiss cheese, and couldpotentially shed light towards understanding and potentially minimizing split defect formation in Swiss cheese.