HS-SPME-GC-MS method for shelf-life monitoring of lactose free dairy products

Shelf-life study is an important aspect in a food product development, especially during the lockdown phase of the COVID-19 emergency in which many companies faced production and supply chain challenges to make their products longer available on the shelf. Therefore, the right tools to correctly define the shelf-life and prevent problems related to safety and loss of quality are needed by the food industries. Lactose-free (LF) dairy products are increasing in popularity following the spread of lactose intolerance. Although some studies have shown that LF dairy products are less stable than a traditional one, due to the greater amount of reducing sugars and free amino acids, the same shelf-life is considered for both type of products, for ex. LF and traditional Mozzarella. In this study a Head-Space-Solid-Phase-Microextraction (HS-SPME) coupled with Gas-Chromatography-Mass-Spectrometry (GC-MS) method has been used to monitor volatile compounds during the shelf-life in Powdered Infant Formula (PIF) and high moisture Mozzarella both traditional and LF. As regards volatile compounds, particular attention has been given to those arising from Maillard reaction, lipid peroxidation and lactose metabolism. Statistically differences resulted between LF and traditional products suggesting that the method here developed, can provide useful information towards shelf-life definition, especially for LF dairy product, which have not been considered until now.