Influencing Factors and Regulation of Aroma Changes during Mozzarella Cheese Reprocessing

To explore the influence factors of aroma changes and develop mitigation strategies for flavor loss in processed Mozzarella cheese manufacturing, the effects of emulsifying salt concentration, citric acid levels, stabilizer dosage, emulsification temperature, emulsification time, and shear rate on the aroma profile of processed Mozzarella cheese were systematically investigated using gas chromatography-mass spectrometry, gas chromatography-olfaction, and electronic nose technology and sensory evaluation. On the basis of single factor experiments, response surface optimization was used to optimize the processing technology of processed Mozzarella cheese, and the aroma changes before and after processing were compared and analyzed. The optimal repreparation process parameters for processed Mozzarella cheese were emulsifying salt mass fraction 1%, stabilizer mass fraction 5.5%, emulsification time 5 min, and shear rate 200 r/min. A comparative analysis of cheese before and after processing showed that 3-methylbutanal and δ-dodecalactone were not detected after processing, which impaired the expression of sensory attributes such as nutty and peach-like flavours in cheese. As an important flavour compound in cheese, acetoin contributed creamy notes and other sensory properties, yet it suffered substantial losses after processing. Therefore, under optimised conditions, aroma compensation experiments were carried out on the processed Mozzarella cheese. After processing, the total number of volatile aroma substances of processed Mozzarella cheese were 38, and the total mass ratio of characteristic flavor substances was 26008.24 μg/kg, which was 12.49% higher than that before processing, indicating a good regulatory effect. It was hoped that this study could provide technical references for the production of processed Mozzarella cheese products.