Effects of microwave heating on the chemical composition and bioactivity of orange juice-milk beverages.

The effect of microwave heating (MH, 65 and 75 °C for 15, 30, and 60 s) on the bioactive compounds, fatty acid profile, and volatile compounds of orange juice-milk beverage (OJMB) was evaluated during 28 days of refrigerated (4 °C) storage. Conventionally pasteurized (75 °C/15 s) and untreated beverages were used as controls. MH-OJMB presented a lower browning index and higher levels of ascorbic acid, total phenolics, and carotenoids, higher antioxidant activity, and greater α-amylase, α-glucosidase, and ACE inhibitory activity than the pasteurized product, similar to the untreated beverage.

Microwave Processing: Current Background and Effects on the Physicochemical and Microbiological Aspects of Dairy Products.

Overheating is still a major problem in the use of conventional heating for milk and various dairy products, because it leads to the lowering of quality and sensory and nutritional values. Microwave (MW) heating has been credited with providing superior-quality dairy-based products with extended shelf-life, representing a good alternative to conventional heat treatment. The main drawback of MW heating refers to nonuniform temperature distribution, resulting in hot and cold spots mainly in solid and semisolid products; however, MW heating has been shown to be suitable for liquid foods, especially in a continuous fluid system.