Effect of soy flour addition and heat-processing method on nutritional quality and consumer acceptability of cassava complementary porridges

BACKGROUND: The nutritional quality of cassava complementary porridge was improved through extrusion cooking and compositing with either defatted of full fat soy flour (65 :35 w/w), and product acceptability by mothers with children of the target population was evaluated. RESULTS: The protein digestibility corrected amino acid score (PDCAAS) of extrusion- and conventionally cooked composite porridges was within the recommendations for complementary foods. The kinetics of starch digestibility showed that all porridges had a rapid rate of starch digestibility, but the rate was lower when defatted soy flour was added and lowest when full fat soy flour was added. The formation of amylase-lipid complexes as shown by X-ray diffraction and differential scanning calorimetry can be attributed to the lower digestibility of extrusion-cooked porridge with full fat soy flour. If fed thrice per day, extrusion-cooked porridge with defatted or full fat soy flour would meet the energy, protein and available lysine requirements of a child aged 6-8 months receiving low or average nutrients from breast milk. All porridges were well received by Mozambican mothers who use cassava as a staple food. The mean scores for sensory liking of all porridges were 3 and above on a five-point hedonic scale. CONCLUSION: Extrusion-cooked cassava/Soy flour porridges have good potential for use as high-energy/high –protein complementary foods and have acceptable sensory properties.The International Institute of Tropical Agriculturehttp://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1097-0010

Nutritional, rheological and sensory properties of extruded cassava-soy complementary porridges

Please read the abstract in the pdf.Thesis (PhD)--University of Pretoria, 2013.gm2013Food Scienceunrestricte

From lab to life: Making storable orange-fleshed sweetpotato purée a commercial reality

Research in Rwanda demonstrated that orange-fleshed sweetpotato (OFSP) purée (steamed, mashed roots) was an economically viable, vitamin A enhancing ingredient in baked products when the purée was produced and used in the same bakery. Having a storable, packaged OFSP purée produced by a firm to supply bakers is an alternative model. Vacuum-packed OFSP purée with preservatives with a four-month shelf-life at 23°C was developed by the International Potato Center under laboratory conditions in 2015. Turning it into a commercial reality required developing a public-private partnership to establish an OFSP purée-bread value chain. The phases in developing the chain are described. Cost-benefit assessment focuses on two points along the chain: the farmers producing roots for the purée factory and purée production. The first OFSP bread began to be marketed in six Tuskys’ stores in June 2015 at a premium price (5 Ksh above its regular bread), reaching 20 stores by August 2016. OFSP bread was well-received by consumers. Purée production became profitable (18% profit margin) when we shifted from using peeled to unpeeled roots--the new product being a “high fiber” purée. Commercial OFSP purée production has been improved and is poised for profitable, larger-scale output

Effect of the addition of soy flour on sensory quality of extrusion and conventionally cooked cassava complementary porridges

BACKGROUND : The sensory properties of the usual conventionally cooked cassava porridge consumed in some regions of Africa and porridges consisting of ccomposited cassava and either defatted or full fat soy flour, with or without extrusion cooking, were evaluated to better understand consumers‟ acceptance. The composited and extruded porridges have superior nutritional quality and added convenience value in the case of extrusion cooked products. RESULTS : Extrusion cooking allowed preparation of porridges with 25% solids content (compared to 10% for conventional cooking) with a viscosity suitable for consumption by infants. Compositing and extrusion cooking reduced the apparent negative sensory attributes of high viscosity, stickiness, translucency, jelly-like appearance and bland flavour that characterize conventionally cooked cassava porridge while increasing slimy appearance of the porridge. The caramel aroma and overall flavour of all extrusion cooked porridges was more intense, with more toasted nutty flavour and aftertaste compared to the corresponding conventionally cooked porridges. Slightly more consumers preferred the conventionally cooked cassava-soy flour porridges. CONCLUSIONS : Compositing cassava flour with fullfat or defatted soy flour and extrusion cooking change the appearance and flavour of porridges while improving the textural properties for better mastication and swallowing by infants. Hedonic adjustment to the changed sensory properties of the porridges in comparison to what mothers and caregivers are used to (conventionally cooked cassava only porridges) is required to ensure acceptance.http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1097-00102016-03-31hb201

Combining sensory evaluation and mental models in the assessment of consumer preferences for and choice of healthy products: Experience from a field experiment in Kenya

This paper combines Just-About-Right (JAR) sensory evaluation and means-end chain (MEC) analysis to examine consumer evaluation of the sensory attributes of conventionally bred biofortified orange-fleshed sweetpotato (OFSP). It specifically examined the role of information on biofortification process on consumers’ expected and actual sensory evaluation of OFSP attributes and the mental models associated with the decision to consume OFSP. It is based on data collected via a field experiment with 504 rural consumers. Each consumer was randomly placed into one of the 3 treatment groups and received: i) general information about biofortification (Control), ii) general and positive information (Treatment 1) and iii) general and negative information (Treatment 2). The study finds, among others, that information on vitamin A (i.e., nutrition), taste and texture were, overall, discriminated by the kind of information provided (i.e., treatment), with texture being considered to be at an inappropriately lower level. Nutrition attribute was, however, considered to be at a higher than appropriate level. The results of the MEC were in line with those of sensory evaluation, with mental constructs (and models) being strongly discriminated by treatment type. It concludes that information consumers receive affect the expected and actual sensory evaluation OFSP attributes and mental models of OFSP consumption. We highlight some implications of these findings

Using preschoolers to improve caregivers' knowledge, attitude, and practices relating to biofortified crops: Evidence from a randomized nutrition education trial in Kenya

Abstract This 2018 randomized controlled trial examined the role behavioral nudges can play in improving caregivers' knowledge, attitude, and practices (KAP) relating to biofortified orange‐fleshed sweetpotato (OFSP). The experiment involved 431 preschooler–caregiver pairs in 15 villages. The preschoolers were enrolled in public‐run Early Childhood Development and Education (ECDE) centers in the respective villages. Caregivers were first exposed to the routine OFSP promotion activities in the area – invited to cooking demonstration workshops and issued with free OFSP vines to plant. A baseline survey followed. Next, the 15 villages were randomized into four study groups (a control and three treatments). The interventions were deployed for 30 days as follows: Treatment 1 – preschoolers issued OFSP‐branded exercise books, class posters, and poems; Treatment 2 – caregivers received phone‐mediated text messages; and Treatment 3 – received the full suite of interventions. This study analyzed the endline and baseline data and finds that, in general, changes in KAP scores were negatively associated with control group (p = .005) and positively associated with Treatment 3 (p = .02). Specifically, Treatment 3 significantly increased caregivers' knowledge of OFSP production, consumption, and vitamin A. Treatment 2 significantly improved their attitude too. It concludes that an integrated complementary nutrition education approach targeting preschooler–caregiver pairs is more effective in increasing knowledge of cultivation and consumption of OFSP. It discusses the implications for the design of more effective nutrition programs targeting households with preschoolers to accelerate the fight against vitamin A deficiency (VAD)

Quality and psychosocial factors influencing purchase of orange-fleshed sweet potato bread

This 2018 study, conducted in six Tusky's supermarkets in Nairobi, Kenya, combined the Just-About-Right, Penalty and Mean-End-Chain analyses to examine the quality and psychosocial factors influencing the purchase of a novel bread made from orange-fleshed sweet potato (OFSP), a biofortified crop, focusing on sixty-one male and eighty female urban OFSP bread buyers recruited at point of purchase. It finds that sensory and psychosocial factors drive purchasing decisions and that some of the bread's sensory characteristics are misaligned with consumers' expectations. It also finds that women and men's evaluations of the bread's characteristics are different, as are their motivations for purchase. However, good sensory attributes and the knowledge of the bread's nutritional value were key drivers. Some misaligned characteristics reveal levers for the reformulation of the bread and present opportunities for segmenting the market. Several other implications of the findings for policy and future improvement of the bread are discussed