ISSN:
1745-4514
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Process Engineering, Biotechnology, Nutrition Technology
Notes:
A study was conducted to determine the influence of pH on the chemical form of phytate in a commercial soy isolate and its effect on zinc bioavailability by monitoring weight gain in weanling rats. Ultrafiltration studies demonstrated that the free phytate content of soy isolate solutions was greatest at pH 5.0; above this the neutralization of soy isolates resulted in the formation of a soluble proteinphytate complex. The bioavailability of zinc from diets providing protein from egg, acid and neutral soy isolates and containing various levels of added zinc was measured. The growth of rats receiving zinc from the neutral soy isolate was significantly lower than that of rats deriving zinc from either the acidic soy isolate or egg white diets. It is proposed that the reduction in bioavailability of zinc caused by the neutralization of soy protein isolate is related to the formation of a protein-zinc-phytic acid complex resistant to hydrolysis in vivo.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1745-4514.1982.tb00307.x
