The recent growing interest in lactose intolerance has resulted in the proliferation of lactose-free products by food manufacturing companies. Since updated papers about lactose and its uses are missing, the main purpose of this review is to investigate this sugar comprehensively. Firstly, its chemical and physical characteristics were studied, following its employment in the food and drug industries. The positive and negative health-related effects of lactose are reported, focusing on the condition of lactose intolerance, for which an adequate lactose-free diet has to be followed to avoid symptoms that impairs quality of life. Considering that EU legislation on lactose-free product labelling is still controversial, suitable options for producing and identifying lactose-free products are suggested, in order to meet lactose-intolerant people’s needs.

Lactose intolerance (LI) is the symptomatic condition that characterizes subjects unable to digest lactose. The main solution consists of reducing or eliminating lactose from one’s diet, and so dairy products, particularly cheeses, are often the first foods excluded. The purpose of this study is to contribute to this topic by creating an updated list of naturally lactose-free (NLF) cheeses. Twenty-five PDO (Protected Designation of Origin) cheeses were selected and analyzed to determine their lactose content. At the same time, interviews with the PDO quality control consortia were carried out to understand which parameters are involved in lactose reduction, based on the cheeses’ product specifications. The analytical techniques used here for lactose determination are the most sensitive (HPAEC-PAD and LC/MS-MS), given their low limit of quantification (LOQ) of less than 10 mg/kg. The majority of selected PDO cheeses resulted in a lactose content less than the LOQ. Because of the high variability allowed in PDO cheeses’ operative conditions, it would be better to case-by-case examine the PDO cheese specification and declare the product as NLF after repeated analysis. The results of the chemical determination of this research allowed to draw up a very useful list of PDO cheeses for both consumers and nutritionists that could be identified as NLF.