Browsing by Subject "fiber structure"

The consumption of meat will be growing in the near future. However, meat production is unsustainable and uses great amounts of environmental resources. Meat consumption could be reduced by usage of meat analogues that are foods or food ingredients that are mostly made of plant proteins and their mouthfeel, texture, nutritional value and visual appearance resemble meat. Faba bean (Vicia faba L.) is a potential raw material for meat analogues although not widely studied. At the moment the most established method for production of meat analogues is wet extrusion (also called high moisture extrusion). The objective of the present work was to produce plant based extrudates with fibrous structure through wet extrusion of faba bean protein concentrate and isolate and study the effect of various processing parameters on the structure of the extrudates. Wet extrusion of faba bean protein fractions is not widely studied, so there was need for this study. Experiments were carried out using split-plot Box-Behnken design, where the variables were faba bean protein isolate content (30, 50 and 70%), water content of the mass (60, 62.5 and 65%) and temperature of the long cooling die (40, 60 and 80 ℃). The response variables were pressure at the die and torque, hardness, gumminess, springiness, chewiness, color, water and oil absorption capacities, water hydration capacity and cutting strength of the extrudate. The results were analyzed using regression analysis. Extrudates were produced successfully in all the experiments, and they had fibrous structure to some extent. The content of protein isolate had significant effect on torque, hardness, gumminess, chewiness, cutting strength, water absorption capacity and lightness. Water content of the mass had also significant effects on torque, hardness, gumminess, chewiness, cutting strength, water absorption capacity and lightness, although the effect was mostly smaller than isolate contents. The temperature of long cooling die had effect only on perpendicular cutting strength and water absorption capacity and the effects were very small. This study showed that producing fibrous plant based extrudates through wet extrusion is possible using faba bean protein isolate and concentrate. The best structures of extrudates were obtained with 30–50% isolate content. Water content didn’t have as clear optimum values as isolate content, but samples with soft and good fibrous structure were obtained at water content of 62.5–65%. In the future the effects of extruder barrel temperature or addition of some other ingredient on the structure of extrudates could be investigated. Faba bean proteins are a potential raw material for plant based extrudates.