Changes in physico-chemical and rheological properties of rice during flaking.

Rajni, Mujoo. and Zakiuddin Ali, S. (2000) Changes in physico-chemical and rheological properties of rice during flaking. International Journal of Food Properties, 3 (1). 117-135, 34 ref..

PDF INTERNATIONAL_JOURNAL_OF_FOOD_PROPERTIES,_3(1),_117-135_(2000).pdf Restricted to Registered users only Download (888kB)

Abstract

Physicochemical, pasting and flow behaviour properties of raw, flaked and roast-parboiled rice were investigated, and changes occurring within the grain during flaking were evaluated. During roast-parboiling, gelatinization of starch increased hydration capacity, swelling power and solubility of the rice. Flaking further increased these properties by damaging starch contained within the rice during application of mechanical force. Changes were greater in flakes produced by a roller-flaker as opposed to those produced by an edge-runner. Flour slurries in a Rapid Visco Analyser demonstrated pasting characteristics with typical pregelatinization profiles; roast-parboiled and flaked rice had higher initial viscosities but lower peak viscosities than raw rice. All samples demonstrated non-Newtonian, pseudoplastic behaviour for viscosity and flow curves taken over a wide range of shear rates. All viscosity curves contained typical hystereses loops, indicative of a thixotropic nature. Flakes derived from a roller-flaker had higher starch breakdown (indicated by low viscosity and greater thixotrophy) than flakes derived from an edge-runner, which contained more heat damaged starch.

Item Type:	Article
Uncontrolled Keywords:	FLAKING-; FLOW-; FUNCTIONAL-PROPERTIES; PHYSICAL-PROPERTIES; RICE-; PASTING-PROPERTIES; PHYSICOCHEMICAL-PROPERTIES
Subjects:	600 Technology > 08 Food technology > 21 Cereals > 01 Rice 600 Technology > 08 Food technology > 14 Physical properties 600 Technology > 08 Food technology > 05 Processing and Engineering
Divisions:	Grain Science and Technology
Depositing User:	Food Sci. & Technol. Information Services
Date Deposited:	19 Jul 2011 05:05
Last Modified:	28 Dec 2011 09:43
URI:	http://ir.cftri.res.in/id/eprint/3332

Actions (login required)

View Item