Spray drying of whey products

01.04.2004 - 30.09.2004
Auftragsforschungsprojekt
Whey has been known for decades as a product of high nutritional value. Today, the development of markets using whey powder and fractions of whey as ingredients in foodstuffs for human and animal consumption have transformed the previously troublesome by-product whey into a valuable product for the food industries. All types of whey can be spray-dried. Each, however, requires its own handling techniques. Layouts for spray-dried whey can vary from the very simple to the sophisticated. Generally speaking, sweet (cheese) whey is easier to dry than acid whey. Ordinary whey powder obtained by this process is very fine, dusty, hygroscopic and therefore caking. Hygroscopicity and caking are influenced by the type of whey and by local climatic conditions. The hygroscopicity, caking and all the problems associated with the stickiness of ordinary whey powder are mainly due to lactose being present in an amorphous glassy state. In the spray drying of milk products, lactose is in an amorphous state and is not stable in atmospheric air or normal humidity. The only form of lactose that is stable to humidity is a-lactose monohydrate. Since the lactose content of whey powder comprises more than 70% of the total solids in comparison with 30% in whole milk the problem of the lactose content in whey powder is more severe. However, since the solubility of lactose is 17 g/100 cm3 H2O at 20°C, it is easy to guide the drying process in such a way that a great part of the lactose can be transformed to the stable α-lactose monohydrate form during the drying process. The influence of water content and glass transition temperature on the ¿stickiness¿ of the product is also part of the project. It was the goal of the work to improve the drying process of different kind of whey without using drying aids like malt dextrin.

Personen

Projektleiter_in

Institut

Contract/collaboration

  • Lactoprot AG

Schlagwörter

DeutschEnglisch
SprühtrocknungSpray drying
MolkeWhey
LactoseLactose
GlasübergangstemperaturGlass transition temperature

Externe Partner_innen

  • Lactoprot AG

Publikationen