STABILIZATION OF CALCIUM SENSITIVE PLANT PROTEINS BY κ‐CARRAGEENAN

Abstract

The stabilizing effect of κ‐carrageenan on 0.15% solutions of coconut, glandless cottonseed, peanut and soy protein isolates was investigated at neutral pH ranges. Addition of 0.01 M calcium decreased protein stability by 75–88% in carrageenan‐free solutions and only by 30% in solutions containing 0.2g carrageenan per g protein. The order of mixing carrageenan, Ca ++ , and protein solutions adversely affected stability only when carrageenan was added last. Electron microscopy of stable fractions revealed the presence of many 100—500Å protein globules, both complexed with κ‐carragecnan and free in solution. Protein stabilization appeared to be related to the formation of double helix junction zones by κ‐carrageenan.