Studies on the development of texturized vegetable products by the extrusion process.

Abstract

Thiamin retention in extruded cowpea, mungbean, defatted soybean and air classified mungbean products was studied by a least squares regression equation using process temperature, screw speed, buffer pH and moisture content as the major independent variables, The increase in process temperature, pH and screw speed variables effected the decrease of thiamin retention values, while the increase in moisture content increased retention. The heat generation due to increase of stress force caused by increased screw speed presumably resulted in the thiamin retention values which were lower than expected. .The carbohydrate and protein of the feed material flours protected the thiamin during the thermoplastic extrusion process.

Nutritional aspects of food extrusion: a review

“…It was found that, at a given process temperature during extrusion cooking of cowpea and mung bean, the available lysine decreased with increasing feed moisture content at 93–167 °C barrel temperature, 30–45% feed moisture and 100 to 200‐r.p.m. screw speed (Pham & Del Rosario, 1984). Owing to the complex nature of interactions between extruder conditions, these changes might not be related to a single factor.…”

Efeito da temperatura de extrusão na absorção de água, solubilidade e dispersibilidade da farinha pré-cozida de milho-soja (70:30)

“…A diminuição da solubilidade de proteína pode ser devido, conforme HORVÁTH & CZUKOR [16], ao fato da ocorrência de desnaturação das proteínas de soja, e de acordo com PHAM & DEL ROSÁRIO [30], esta redução pode ser atribuída às interações não covalentes entre cadeias de polipeptídeos, à formação de novas ligações dissulfídicas ou de ligações não peptídicas envolvendo grupos carboxílicos e amínicos.…”

Modeling Thermal and Mechanical Effects on Retention of Thiamin in Extruded Foods

“…S tudies have reported that thiamin loss in extruded products increases with temperature (Beetner and others 1974;Beetner and others 1976;Maga and Sizer 1978;Cheftel 1986;Pham and Del Rosario 1986;Guzman-Tello and Cheftel 1987;Hakansson and others 1987;Schlude 1987;Ilo and Berghofer 1998). Among these researchers, those who varied screw speed also reported increased thiamin loss with higher screw speeds (Beetner and others 1974;Pham and Del Rosario 1986;Guzman-Tello and Cheftel 1987;Killeit 1994;Ilo and Berghofer 1998).…”

“…Among these researchers, those who varied screw speed also reported increased thiamin loss with higher screw speeds (Beetner and others 1974;Pham and Del Rosario 1986;Guzman-Tello and Cheftel 1987;Killeit 1994;Ilo and Berghofer 1998). Higher screw speeds shorten residence times, which at constant temperature would normally be associated with less thiamin loss.…”