Development and Characterization of Extruded Product Using Carrot Pomace and Rice Flour

Abstract

Dehydrated carrot pomace was added in different proportions (10-30%) to rice flour. The formulation was extruded at different moisture content (17-21%), screw speed (270-310 rpm) and die temperature (110-130°C). The experimental combinations were decided based on central composite rotatable design for four variables at five levels of each variable. The lateral expansion, bulk density, water absorption index, water solubility index, hardness and sensory characteristics were measured as responses. Significant regression models were established with the coefficient of determination, R² greater than 0.70. The results indicated that pomace proportion, screw speed and temperature significantly influenced (P<0.10) lateral expansion; moisture content and screw speed for bulk density; pomace proportion and temperature for water absorption index and water solubility index, pomace proportion, screw speed and temperature for hardness and screw speed for sensory score. The compromised optimum condition obtained by numerical integration for development of extrudates were: carrot pomace of 11.75% in rice flour, moisture content 19.92%, screw speed 249.1 rpm and die temperature 114.3°C. Sensory evaluation revealed that carrot pomace could be incorporated into ready-to-eat expanded products upto the level of 11.75%.

Effect of feed composition, moisture content and extrusion temperature on extrudate characteristics of yam-corn-rice based snack food

“…At higher temperature, starch granule is disrupted and more water is bound to the starch molecule resulting in increased WAI. Kumar et al (2010) examined the increased effect of WAI with increased temperature which is in support of our current findings. WAI has been reported to increase with increase in moisture content of feed (Ding et al .…”

“…Since, in our blend, the proportion of protein is high, the increase might be due to partial protein denaturation at higher temperature (Oikonomou and Krokida 2011). Kumar et al (2010) indicated that WSI increases with increase in fibrous content in the feed formulation, which supports our findings (Fig. 2b).…”

“…Increased moisture content increased hardness significantly at p ≤0.05 (Table 4), which might be due to reduced expansion of the extrudate and lower rate of starch degradation at higher moisture content. Relationship between hardness and moisture content has widely been investigated by researchers (Sebio and Chang 2000;Kumar et al 2010;Chiu et al 2012). Variation of hardness with the barrel temperature was prominent (p ≤0.001).…”

Stability and Functionality of Grape Pomace Used as a Nutritive Additive During Extrusion Process

“…Briefly, 200 µl of the extracts were mixed with 12.5 µl of Folin-Ciocalteu reagent and then 37.5 µl 20% Na 2 CO 3 in a 96-well legumes, fruits, and vegetables [23]. Studies on the incorporation of pomace into extruded products showed that increased pomace levels beyond a certain level had negative effect on the expansion quality [16,17,20,27,28]. However, recent studies indicated that carrot and cherry pomace incorporation into cornstarch extrudates resulted in better expansion and nutritional quality [18,19].…”

“…Lower values of WSI are often associated with the less dextrinization of starch during extrusion. Addition of GP provides insoluble fiber and other hydrophilic groups that can interact with starch to reduce the overall gelatinization, and hold water instead of being solubilized [27,43]. In fact cherry pomace in swelled starch granules trapes water and lowers WSI [18].…”