Calcium-fortified soymilk

Abstract

© Springer Science+Business Media New York 2013. All rights reserved. Natural soymilk has a low content of calcium and is often supplemented with calcium to levels found in cow's milk. It is possible to supplement with a wide variety of calcium salts. These will have different solubilities and different effects on the properties of the soymilk. Soymilk is subjected to pasteurisation or sterilisation processes to ensure that it is safe and has a long shelf life. The main problem arising from addition of soluble calcium salts is that they will reduce heat stability. This becomes a problem if addition results in a decrease in pH and an increase in ionic calcium. Stabilising salts such as disodium hydrogen phosphate and tri-sodium citrate are useful for improving heat stability of calcium-fortified soymilk. Calcium salts with low solubility such as calcium carbonate and calcium phosphate can also be added. One advantage is that they do not change pH and ionic calcium to the same extent as addition of soluble salts. One disadvantage results from their insolubility. How these different combinations of calcium salts and stabilising salts affect properties such as particle size and viscosity are discussed in this review. It is worthwhile measuring pH and ionic calcium of fortified beverages to gain a better understanding of their effects on the physical properties and sensory characteristics of soymilk.