The influence of crystallization equipment on the crystallization of concentrated whey

Abstract

The main objectives of this project were to determine the effect of the crystallizer design on lactose crystallization efficiency in concentrated whey. Two different crystallizers were used, one presenting a central agitation (tank 1) and the other presenting a peripheral agitation (tank 2). All others crystallization parameters were kept constant such as cooling rate; temperature; stirring speed; crystallization time and concentration of soluble solids by treatment.The best rate for lactose crystallization in concentrated whey was obtained applying central stirring and 55 ºBrix [Time (min) = 0.1927 (% lactose crystallization) + 21.681] and [Time (min) = -0.06 (ºBrix) + 51.233] under the cooling rate of -0.34 ºC ± 0.05 ºC per minute during the first hour and achieving the final temperature of 25.8º ± 1.2 ºC after 4 hours, central stirring promoted highest rates of lactose crystallization in concentrated whey with 50, 55 and 60 ºBrix.The type of Tank for crystallization and the dry matter content in concentrated whey affect whey powder rehydration, stickiness into the chamber, different levels of lactose crystallization and storage of the powder.