Greater consumer demand for nutritious extruded food products with enhanced bioactive compounds has shifted research focus towards incorporation of bioactive rich ingredients with traditionally extruded starch materials. Recent research has highlighted the importance of bioactive compounds in human health and nutrition. An evaluation of the available literature reveals that the level of bioactive compounds in extruded products is influenced by extrusion process variables. Shear, temperature, resonance time and water content are all factors which contribute to the overall composition of extruded products. In addition, food structure may also exhibit a role in the potential release of functional bioactives. This paper reviews the effect of extrusion on bioactive compounds such as phenolic compounds, anthocyanins, isoflavones and their antioxidant activity. Factors influencing levels and stability during extrusion are also discussed.

Effects of extrusion on the polyphenols, vitamins and antioxidant activity of foods

An increase in celiac consumers has caused an increasing interest to develop good quality gluten-free food products with high nutritional value. Snack foods are consumed worldwide and have become a normal part of the eating habits of the celiac population making them a target to improve their nutritive value. Extrusion and deep-frying of unripe plantain, chickpea, and maize flours blends produced gluten-free snacks with high dietary fiber contents (13.7-18.2 g/100 g) and low predicted glycemic index (28 to 35). The gluten-free snacks presented lower fat content (12.7 to 13.6 g/100 g) than those reported in similar commercial snacks. The snack with the highest unripe plantain flour showed higher slowly digestible starch (11.6 and 13.4 g/100 g) than its counterpart with the highest chickpea flour level (6 g/100 g). The overall acceptability of the gluten-free snacks was similar to that chili-flavored commercial snack. It was possible to develop gluten-free snacks with high dietary fiber content and low predicted glycemic index with the blend of the 3 flours, and these gluten-free snacks may also be useful as an alternative to reduce excess weight and obesity problems in the general population and celiac community.

Gluten-Free Snacks Using Plantain–Chickpea and Maize Blend: Chemical Composition, Starch Digestibility, and Predicted Glycemic Index

This study investigated the effects of storage conditions: cool (15 ± 1°C, 90% relative humidity (RH)), ambient (23 ± 2°C, 60% RH) and higher (38 ± 2°C, 60% RH) on changes in physicochemical quality attributes of two cassava flour cultivars (TME 419 and UMUCASS 36) packaged in paper bags and stored for 12 weeks. Physicochemical and microbial qualities were studied at weeks 0, 4, 8 and 12. Moisture content decreased from 12.0% to 7.1% and 9.8% to 6.8% in cultivars ‘TME 419’ and ‘UMUCASS 36’, respectively. Carotenoid content was higher in cultivar (cv.) ‘UMUCASS 36’ (2.5 ± 0.10 mg/g) compare to cv. ‘TME 419’ (1.8 ± 0.11 mg/g). Colour indices of the cassava flour were significantly influenced by storage duration. A slight decrease in microbial load from 5.4 to 4.8 log CFU/g was observed, with increase in temperature from 15°C to 38°C at the end of storage. The ambient storage condition best maintained nutritional and physicochemical quality.

Effects of storage conditions and duration on physicochemical and microbial quality of the flour of two cassava cultivars (TME 419 and UMUCASS 36)

Purpose




The purpose of this paper is to evaluate consumers’ willingness to pay (WTP) for composite flour bread produced with a blend of 15-40 per cent cassava flour blended with wheat flour in Ghana




Design/methodology/approach




The analysis is based on interviews with 350 consumers in the Ashanti and Eastern Regions of Ghana to assess their awareness, perceptions and WTP for cassava-wheat composite bread From these consumer interviews, a hedonic regression model was applied to evaluate consumers’ WTP for various attributes of composite flour bread Price-related and health-related perceptions of consumers on cassava-wheat composite bread were investigated with perception indices Multi-attribute preference-based contingent ratings that rate product attributes in terms of importance to consumers was employed The implicit prices of the product attributes representing the contribution of the product attributes to the WTP amount were also computed




Findings




The paper finds that consumers who are aware of cassava-blended flour bread and who like its taste and texture are willing to pay more than consumers who are unaware This leads to a policy recommendation advocating increased advertising of the economic and nutritional benefits of cassava-wheat blended composite flour bread




Research limitations/implications




Future studies should explore the choice experiments to examine preferences for the food product




Originality/value




This paper evaluates consumers’ WTP for composite flour bread produced with a blend of 15-40 per cent cassava flour and wheat flour Given widespread reliance on imported wheat flour and the simultaneously large volumes of locally available cassava, it is important to consider opportunities for import substitution (and possible cost reduction for consumers) of blended flour products such as cassava-wheat composite flours Nigeria has imposed a 10 per cent blending requirement for this reason Ghana has taken important measures recently for the development of high-quality cassava flour, and so research on its potential and actual uptake is welcomed and highly relevant to food security and agribusiness development

Consumer perceptions and willingness to pay for cassava-wheat composite bread in Ghana.

This study was designed for nutrition fortification of cassava flour lafun with soya beans. Five different samples of lafun to soya beans were (100:0, 90:10, 80:20, 70:30, and 60:40). The following proximate analysis of these samples were carried out ash determination, crude fiber, protein, moisture and fat. The results ranges were 0.84-2.46%, 1.63-2.12%, 1.16-12.54%, 13.01- 11.28% and 0.44-2.62% respectively. Functional properties of the formulation were also evaluated and the result obtained showed that loose and packed bulk density were 0.2-0.3% and 0.5- 0.55%, the water absorption and oil capacity were 163-127% and 167-113.5% respectively. Swelling capacity and disposability were also 6.2-2.95% and 93.7-81.4% while the regulation and solubility are 24.5-18.99 and 6.7-4.95 respectively. The pasting properties results were also revealed that at a peak of 244.17-112.33rvu, the trough was 129.17-58.83rvc,and the breakdown was 115.00-52.50rvu, the final viscosity was between 164.33-81.92rvu,set back 35.17-23.08rvu, peak time 4.46-3.91 and pasting temperature 63.15-63.850C. DOI: 10.5901/jesr.2013.v3n8p163

/pdf/functional-and-nutritional-characteristics-of-cassava-flour-19hlr5oni1.pdf

Functional and Nutritional Characteristics of Cassava Flour (Lafun) Fortified with Soybeans

Low protein and poor functionality limit the use of cassava flour in snack foods, which were modified using blends with cereal and/or legume flours. Native, malted (using alpha-amylase) as well as malted and pre-gelatinized was blended with cereal (finger millet and whole wheat flours) and/or legume (chick pea flour). Extrudates were prepared at a screw speed of 100 rpm and die temperature of 180 °C. Malted flour based extrudates had lower starch content than native flour. Gram malted cassava based blends gave products with the highest protein. In vitro starch digestibility was the highest for pre-gelatinized flour based mixes. Extrudates with low fat and energy have scope as low calorie snacks for obese and diabetic people.

https://www.tandfonline.com/doi/pdf/10.1080/10942910902934090

J.T. Sheriff

Papers

Nutritional, Functional and Physical Properties of Extrudates from Blends of Cassava Flour with Cereal and Legume Flours