Lactose hydrolyzed whey: drying challenges

Abstract

The industry has diversified its range of products over the years to meet the demand of consumers for lactose-free or low-lactose products. Several lactose free dairy products are already well established in the market, such as UHT milk, yogurt and cheese. The latter has the whey as its derivative which is widely used as an ingredient in the food industry. However, the market of lactose-free products presents technological challenges in drying, transport and storage of some products such as whey. Technological problems like pavement and adhesion to the equipment can occur because traditional whey is a product of difficult maintenance of the glass transition. The lactose hydrolysis promotes the release of glucose and galactose in milk. These two sugars have a lower glass transition than lactose, causing a reduction of the glass transition in the lactose-free product. Therefore, the lactose-free whey becomes even more difficult to dry compared to whey with intact lactose. Thus, the industries have sought the best operating parameters for drying, combined with modificationsin the composition, favoring the maintenance of the vitreous state of the delactosed whey.