INFLUENCE OF SALTS AND pH ON THE FIRMNESS OF COOKED SNAP BEANS IN RELATION TO THE PROPERTIES OF PECTIN

Abstract

ABSTRACT Solute conditions inside cooked bean pods were adjusted by soaking the pods in different solutions. Interactions of Ca ++ and Na + showed increasing firmness as Ca ++ concentration was raised and decreasing firmness as Na + was raised. Chelating agents removed Ca ++ and decreased firmness. Higher pH gave lower firmness except in the presence of excess Ca ++ . The presence of Na + decreased the effect of pH on firmness. Urea decreased firmness when pods had been previously treated with a chelator. The effects of treatments on firmness were related to the behavior of pectin solutions and gels.