Lactose-free Dulce de leche: compositional characterization, browning and texture profile

Produced and consumed in Latin America, mainly Brazil and Argentina, Dulce de leche (DL) is a product held in universal high regard for its flavor (Silva et al., 2015). In addition to flavor, it has a typical color and texture acquired during the process of product concentration due to non-enzymatic browning reactions (Francisquini et al., 2018). Although Brazilian legislation determines the mandatory and permitted components for the manufacture of DL (Brasil, 1997), the product can present different characteristics that vary significantly between processors and regions of the country (Gaze et al., 2015). Different treatment patterns, such as heating time and temperature, directly interfere with the final product's physico-chemical and sensory attributes (Stephani et al., 2018). These characteristics are strongly related to the nutritional and technological parameters as well as sensory quality of the DL, and as a consequence affect the consumer's purchase intention (Gaze et al., 2015).

There are some drawbacks associated with eating dairy products by those who are lactose intolerant or allergic to milk proteins (Suri et al., 2018). Lactose intolerance is the name given to the inability to digest milk's predominant sugar, which occurs in organisms that do not produce or insufficiently produce the digestive enzyme called lactase, or β-d-galactosidase. This enzyme breaks down lactose into two monosaccharides, glucose and galactose, allowing it to be absorbed through the intestinal mucosa (Garballo-Rubio et al., 2017; Suri et al., 2018).

Lactose intolerance is one of the most common food sensitivities in the world and it is estimated that 70% of the world's adult population has some level of intolerance to this sugar, with a higher incidence in individuals from South America, Africa, and Asia (Francisquini et al., 2019; Jansson-Knodell et al., 2020). Food industries have a role in keeping up with trends in the population's eating habits and needs, so the inclusion of lactose-free foods in the market is desirable. Consequently, the dairy market has continuously launched new products to fit this profile (Garballo-Rubio et al., 2017).

The process for removing lactose typically includes the addition of the enzyme β-D-galactosidase (lactase) to milk (Francisquini et al., 2019). In addition to the purpose of allowing lactose intolerants to consume the product,...