DOI: 10.1094/CC-83-0363 |  VIEW ARTICLE

Preparation of High-Quality Protein-Based Extruded Pellets Expanded by Microwave Oven.

E. Aguilar-Palazuelos (1,2), J. de J. Zazueta-Morales (1), and F. Martínez-Bustos (2,3). (1) Maestría en Ciencia y Tecnología de Alimentos, Universidad Autónoma de Sinaloa, Apdo. Postal 1354, Culiacán, Sin., C.P. 80000, México. Phone: (52) 667 7136615. Fax: (52) 667 7136615. E-mail: <zazuetaj@uas.uasnet.mx> (2) Ciencia de Materiales, CINVESTAV Querétaro, Apdo. Postal 1-798, Querétaro, Qro., C.P. 76230, México. Phone:(52) 442 4414905. Fax: (52) 442 4414938. (3) Corresponding author. E-mail: <fmartinez@qro.cinvestav.mx> Cereal Chem. 83(4):363-369. Accepted March 14, 2006. Copyright 2006 AACC International, Inc.

The aim of this work was to study the effects of extrusion barrel temperature (75–140°C) and feed moisture (16–30%) on the production of third-generation snacks expanded by microwave heating. A blend of potato starch (50%), quality protein maize (QPM) (35%), and soybean meal (SM) (15%) was used in the preparation of the snacks. A laboratory single extruder with a 1.5 × 20.0 × 100 mm die-nozzle and a central composite routable experimental design were used. Expansion index (EI) and bulk density (BD) were measured in expanded pellets, viscosity at 83°C (V(83)), thermal properties, and relative crystallinity were measured in extruded pellets. EI increased and BD decreased when the barrel temperature was increased, while the feed moisture effect was not significant. V(83) increased when feed moisture increased. Extrusion modified the crystalline structures of the pellets and the X-ray data suggests the formation of new structures, probably due to the development of amylose-lipid complexes. The maximum expansion of pellets was found at barrel temperatures of 123–140°C, and feed moisture of 24.5–30%. It is possible to obtain a functional third-generation snack with good expansion characteristics using a microwave oven, and this snack has health benefits due to the addition of QPM and SM.