Cereal food products are an important part of the human diet with wheat being the most commonly consumed cereal in many parts of the world. Extruded snack products are increasing in consumer interest due to their texture and ease of use. However, wheat based foods are rich in starch and are associated with high glycaemic impact products. Although legume materials are generally rich in fibre and protein and may be of high nutritive value, there is a paucity of research regarding their use in extruded snack food products. The aim of this study was to prepare wheat-based extrudates using four different legume flours: lentil, chickpea, green pea, and yellow pea flour. The effects of adding legumes to wheat-based snacks at different levels (0%, 5%, 10%, and 15%) during extrusion were investigated in terms of protein digestibility. It was observed that fortification of snacks with legumes caused a slight increase in the protein content by 1%–1.5% w/w, and the extrusion technique increased the protein digestibility by 37%–62% w/v. The product developed by extrusion was found to be low in fat and moisture content.

Liquid-side mass-transfer coefficients (k L a) were measured in surface aerators and self-inducingtype reactors. The measurements were made in 1.0-and 1.5-m-i.d. cylindrical and 8.2 × 8.2-m square tanks using physical absorption of oxygen. The effect of liquid submergence was investigated in detail. Further, the effects of the diameter of the tank, the ratio of the impeller diameter to the tank diameter, and the clearance of the impeller from the tank bottom were also studied. Three different impeller designs were investigated as surface aerators. Single and multiple impellers were employed in the case of self-inducing reactors. The power consumption was varied in the range of 30-1000 W/m 3 . Suitable correlations were developed for both types of reactors.

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The aim of this study is to understand the reasons for instability in the operation of a gas inducing impeller and to suggest the ways to eliminate the instability. Experiments were performed in a 1 m diameter vessel. The impeller clearance from the tank bottom was 0.52 m. The effects of impeller diameter, impeller blade width, blade thickness, impeller blade angle, shape of the impeller blade, impeller position with respect to the stator, impeller submergence and stator geometry on the instability were investigated. Phenomenological description has been provided for the occurrence of instability. An optimum design of a stator-impeller combination has been proposed for gas dispersion and stable operation.Le but de cette etude est de comprendre les causes d'instabilite dans le fonctionnement d'une turbine induisant du gaz et de proposer des facons d'eliminer cette instabilite. Des experiences ont ete menees dans un reservoir de 1 m de diametre. Le degagement de la turbine par rapport au fond du reacteur etait de 0,52 m. On a etudie I'effet du diametre de turbine, de la largeur de lame, de I'epaisseur de lame, de I'angle de la lame, de la forme de lame, de la position de la turbine par rapport au stator, de la submersion de'la turbine et de la geometrie de I'aubage fixe sur I'instabilite. Le phenomene d'apparition de I'instabilite est decrit. Une conception optimale de I'ensemble stator-turbine est propose pour la dispersion du gaz et un fonctionnement stable.