Heat-induced reversible gelation of arachin: kinetics, thermodynamics and protein species involved in the process.

Kella, N. K. D. (1989) Heat-induced reversible gelation of arachin: kinetics, thermodynamics and protein species involved in the process. International Journal of Biological Macromolecules, 11 (2). pp. 105-12. ISSN 0141-8130

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Abstract

Arachin forms a heat-reversible gel under certain experimental conditions. The minimal gelling concentration for this system is 7.25%. Above minimal gelling concentration calculation of thermodynamic parameters for gelation of arachin revealed a constant delta Hbonding (-1220 cal.mol-1) where delta Sbonding values varied with an increase in protein concentration (ranging from -4.01 e.u. at 7.5% to -3.48 e.u. at 10.0%). The main steps involved in the gelation phenomenon include thermal denaturation of arachin, partial aggregation of heat-denatured protein molecules, setting of protein solution and maturation of the gel formed. Gel maturation process follows first order kinetics and is characterized by a large positive delta G+(+) (22,030 cal.mol-1). Determination of delta H+(+) and delta S+(+) for this process revealed that mostly delta S+(+) (-62.9 e.u.) contributes to the large positive delta G+(+), thus decreasing the overall rate of gel maturation process. This large negative delta S+(+) value probably arises from a loss of entropy of protein molecules because of their increased involvement in gel network formation. The polymer gel network seems to be primarily contributed by a part of both arachin dodecameric and hexameric species.

Item Type:	Article
Uncontrolled Keywords:	Arachin; protein-protein interactions; gelation; kinetics of gelation; thermodynamics of gelation
Subjects:	600 Technology > 08 Food technology > 16 Nutritive value > 03 Proteins 600 Technology > 08 Food technology > 33 Nuts
Divisions:	Protein Chemistry and Technology
Depositing User:	Food Sci. & Technol. Information Services
Date Deposited:	20 Mar 2018 08:45
Last Modified:	20 Mar 2018 08:45
URI:	http://ir.cftri.res.in/id/eprint/2357

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