Organic acids.The effects of a series of organic acids--malic, citric cit·ric adj. Of or relating to citric acid. citric Adjective of or derived from citrus fruits or citric acid Adj. 1. and phytic acids--on the properties of edible gelatin gelatin or animal jelly, foodstuff obtained from connective tissue (found in hoofs, bones, tendons, ligaments, and cartilage) of vertebrate animals by the action of boiling water or dilute acid. films have been studied by scientists. An increase in the acid concentration of malic acid malic acid: see Krebs cycle. films can lead to a systematic decrease in their tensile strength and elastic modulus. Increases in tensile strength were also found for some concentrations of citric and phytic acids, but these changes were not monotonic monotonic - In domain theory, a function f : D -> C is monotonic (or monotone) if for all x,y in D, x <= y => f(x) <= f(y). ("<=" is written in LaTeX as \sqsubseteq). with acid concentration. The tensile strength of 1% malic acid film at twice that of the control film may be caused by ionic cross-linking. This cross-linking effect did not significantly affect the water vapor permeability of the malic and citric acid citric acid or 2-hydroxy-1,2,3-propanetricarboxylic acid, HO2CCH2C(OH)(CO2H)CH2CO2 films. Films made with the more bulky phytic acid did, however, show a 50% increase in water vapor permeability. All the acids lead to a decrease in the melting temperature of the films, compared with the control. Contact: Robert Kimmel, Department of Packaging Science, Clemson University, B-212 Poole Agricultural Center, Box 340370, Clemson, SC 29634. Phone: 864-656-6534. Email: kimmel@clemson.edu. |
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