The effect of transglutaminase on the characterization of lactose-free skimmed milk powder

The development of hydrolyzed lactose powder products involves technological, sensory, and nutritional challenges (adhesion in the drying chamber, browning of the powder, and formation of Maillard reaction products). Recent studies have analyzed the use of transglutaminase (TGase) to reduce product adhesion in dryers and the intensity of the Maillard reaction. This study aimed to evaluate the application of TGase to powdered dairy products with and without hydrolyzed lactose. Skimmed milk powder was dried under four different treatments with three replicates resulting in 12 products (Treatment 1 skimmed milk powder; Treatment 2 skimmed milk powder with lactase; Treatment 3 skimmed milk powder with TGase; Treatment 4 skimmed milk powder with lactase and TGase). The product retention capacity in the equipment; compositional, physicochemical, and morphological attributes; particle size; and Maillard reaction markers were analyzed. The use of TGase did not affect drying conditions or powder processing. Transglutaminase increased the particle size of the products without altering their bimodal conformation. The color of the product was not modified regardless of whether TGase was added. In the hydrolyzed product with added TGase, the HMF value increased (6–21 times). The use of TGase did not affect the hydrolysis of lactose, and a decrease in the intensity of the casein bands (glutamine-lysine crosslinking) was observed by electrophoresis. This study led to new hypotheses and possibilities for future studies to elucidate the influence of TGase addition to powdered dairy products.