DisplayTitle

Development and Characterization of Extruded Pellets of Whole Potato (Solanum tuberosum L.) Flour Expanded by Microwave Heating

¹Universidade Estadual de Campinas, Departamento de Tecnologia de Alimentos, Caixa Postal 6121, CEP 13.083-970, Campinas, São Paulo, Brasil. E-mail: yokic@fea.unicamp.br ²Universidad A. de Sinaloa, Maestría en Ciencia y Tecnología de Alimentos - FCQB, Culiacán, Sin., C.P. 82000, México. E-mail: zazuetaj@uas.uasnet.mx ³CINVESTAV-IPN-Unidad Querétaro, Libramiento Norponiente No. 2000, Fracc. Real de Juriquilla, C.P. 76230, Querétaro, Qro., México. Phone: +52-442-441-4905. Fax: +52-442-441-4938. E-mail: fmartinez@qro.cinvestav.mx

In various Latin American countries, large volumes of potato are classified as unsuitable for use as food and destined for use as feed. This raw material has a high starch and fiber content that could be used in the production of different kinds of food. The objective of this research was the preparation and characterization of extruded whole potato pellets expanded by microwave heating. A 3³ central composite routable experimental design and response surface methodology were used. The barrel temperature (BT, 93–127°C), feed moisture (FM, 19–29%), and corn starch concentration (CS, 3–37%) in the blends were evaluated. CS was the most important variable affecting the functional properties of the expanded pellets. Adding CS to the blends increased the expansion index and viscosity and improved luminosity, decreasing the apparent density and breaking force of the products. Low BT and especially high FM increased the luminosity of the expanded pellets. Increasing FM content increased the viscosity of the expanded pellets. The best functional characteristics for the expanded pellets were obtained using a blend of 63% potato flour and 37% CS, extruded at 110°C BT with 24% FM content. Nonfood-grade whole potato flour showed good potential for use in the production of expanded pellets with acceptable functional properties.