Sensory perception of different acidulants in flavoured sports drinks

This study investigated the implications of substituting citric acid with other acidulants; malic acid, fumaric acid and tartaric acid and a combination thereof (Fruitaric® acid), in a flavoured sports drink. A trained sensory panel (n=10) compared the sourness intensity of the acidulants at both equal sour and equal weight concentrations in water and in a Grape and a Lemon&Lime flavoured sports drink. The sensory panel compared the temporal character of the acidulants at equal sour concentrations in water and both sports drink flavours. This included determining the rate, onset, duration and maximum intensity parameters of the perceived sourness. To determine if repeated exposure testing of sports drinks with the different acidulants added at equal sour concentrations would lead to hedonic adjustment, consumers (n=128) were repeatedly exposed to a Lemon&Lime flavoured sports drink over a period of 22 days. Citric acid, the acidulant currently used in the sports drinks, served as a reference in all the comparisons. Previously determined equal sour concentrations of tartaric and Fruitaric® acids as determined in water was found to be equally sour to citric acid when applied to water and a Lemon&Lime flavoured sports drink but less sour than citric acid when compared in the Grape flavoured sports drink. Malic and tartaric acids were found to be equal sour to citric acid in water and both sports drink flavours. The application of equal sour concentrations seemed to be flavour specific. Sourness of water and more complex solutions, such as flavoured sports drinks, seemed to be dependant on multiple factors including pH, titratable acidity, molecular weight, acidulant concentration and oBrix. The results from this study rejected anecdotal reports that acidulants differ in their temporal sensory profiles, although the lack of significant differences may be a function of the specific concentration level (0.2%) used. Repeated exposure testing of Lemon&Lime flavoured sports drinks with different acidulants resulted in hedonic adjustment. Consumer preferences post exposure could not have been predicted with a traditional consumer taste test at the start of the study. The findings of this study surely challenge the validity of sensory evaluation test strategies that rely on single exposure testing to predict long term consumer preferences.Dissertation (MSc)--University of Pretoria, 2009.Food Scienceunrestricte

Effect of kafirin protein coating on sensory quality and shelf-life of 'Packham's Triumph' pears during ripening

BACKGROUND: Pears are exported in large quantities from South Africa resulting in large revenues. Minimisation of quality losses once the fruit has reached the export destination is as important as following strict export and distribution protocols. Kafirin can form edible films. An edible coating, made from a 2 % (w/w) kafirin coating solution was applied as a post-havest treatment to retard quality deterioration of ‘Packham’s Triumph’ pears during storage at the typical ripening temperature (20° C). The changes in physic-chemical and sensory quality were studied over a period of 24 days. RESULTS: The kafirin coating was unable to retard the onset of ripening but decreased the respiration rate and retarded the progression of senescence. However, moisture loss was exacerbated in the kafirin-coated fruit during ripening at 20° C especially towards the end of the shelf-life. CONCLUSION: The coating extended the eat-ripe quality of the pears between one and two weeks. However, appearance of the fruit was unacceptable after 14 days of storage in terms of wrinkled skin. Further work is needed to improve the water barrier properties of the kafirin coating by incorporating a wax or triglyceride into the coating formulation or more simply by applying a kafirin coating to waxed fruit.The European Commission (Enviropak project, INCO2: ICA4-CT-2001-10062) and CSIR Biosciences.http://www.soci.or

An alternative food neophobia scale (FNS-A) to quantify responses to new foods

An alternative Food Neophobia Scale (FNS-A) was developed in three studies to measure food neophobia (reluctance to eat and avoidance of trying new foods). In Study 1, the original food neophobia scale, FNS (Pliner, & Hobden, 1992), was first critically examined leading to modifications in five and omission of two statements. Furthermore, eight positive and eight negative statements were elicited and introduced along with eight original or modified FNS statements to 575 respondents in South Africa, Lesotho, and Botswana. Study 2 (n = 1010) was used to confirm the factorial structure of the scale, and Study 3 (n = 141) was used to test the reliability of FNS-A through test-retest data. The structure of the scale was analyzed using exploratory (Study 1 and 2) and confirmatory (Study 2) factor analysis, eventually leading to four positive and four negative statements regarding new foods, loaded on two factors labelled approach and avoidance. Test-retest reliability at a 2 weeks' time interval as well as convergent and divergent validity measured against other scales was good (Study 3). In all three studies, predictive validity was evaluated against willingness to try or expected liking ratings of unfamiliar or novel food names or food concept descriptions. This evaluation showed satisfactory performance. FNS-A is a promising tool for the quantification of individual responses to unfamiliar or novel foods, but further studies in other populations and contexts are needed to confirm the applicability.Peer reviewe

An alternative food neophobia scale (FNS-A) to quantify responses to new foods

SUPPLEMENTARY TABLE 1. The 24 statements used in the study to describe responses of less (willing) and more (reluctant) neophobic individuals and the codes used to identify the statements (Study 1).SUPPLEMENTARY TABLE 2. Exploratory factor analyses, conducted in ten steps, to identify items that best fit in FNS-A (Study 1).An alternative Food Neophobia Scale (FNS-A) was developed in three studies to measure food neophobia (reluctance to eat and avoidance of trying new foods). In Study 1, the original food neophobia scale, FNS (Pliner, & Hobden, 1992), was first critically examined leading to modifications in five and omission of two statements. Furthermore, eight positive and eight negative statements were elicited and introduced along with eight original or modified FNS statements to 575 respondents in South Africa, Lesotho, and Botswana. Study 2 (n = 1010) was used to confirm the factorial structure of the scale, and Study 3 (n = 141) was used to test the reliability of FNS-A through test–retest data. The structure of the scale was analyzed using exploratory (Study 1 and 2) and confirmatory (Study 2) factor analysis, eventually leading to four positive and four negative statements regarding new foods, loaded on two factors labelled approach and avoidance. Test-retest reliability at a 2 weeks’ time interval as well as convergent and divergent validity measured against other scales was good (Study 3). In all three studies, predictive validity was evaluated against willingness to try or expected liking ratings of unfamiliar or novel food names or food concept descriptions. This evaluation showed satisfactory performance. FNS-A is a promising tool for the quantification of individual responses to unfamiliar or novel foods, but further studies in other populations and contexts are needed to confirm the applicability.Writing of the paper was supported by funding for a project: InnoFoodAfrica from the European Union’s Horizon 2020 research and innovation programme. Finnish University Partnership for International Development (UniPID) provided funding (project code 210000439011) that enabled final discussions among the authors and distribution of the questionnaire in South Africa, Lesotho and Botswana.Multi-item instrumenthj2023Consumer ScienceFood Scienc

Relating sensory profiles of canned amaranth (Amaranthus cruentus), cleome (Cleome gynandra), cowpea (Vigna unguiculata) and Swiss chard (Beta vulgaris) leaves to consumer acceptance

BACKGROUND : The younger generation of South Africans generally do not consume traditional meals prepared using African green leafy vegetables, primarily because they are regarded as bitter, “poverty” foods. Canning of these vegetables could create value‐added products that can be sold in the commercial market. Descriptive sensory evaluation and consumer acceptance testing with young females were used to assess the potential of such products. RESULTS : The sensory attributes of amaranth, cleome and cowpea leaves canned in brine and in a cream sauce were described using 21 attributes grouped by aroma, taste, texture/mouthfeel and aftertaste. Amaranth and Swiss chard products were described as sweet with a popcorn‐like aroma. Cleome products were described as bitter, sour, pungent, chemical‐tasting, astringent, sandy with a metallic mouthfeel and strong aftertaste. Cowpea products were described as having woody and tobacco aromas as well as a chewy and cohesive texture. Among the products canned with a cream sauce, young female consumers preferred amaranth and Swiss chard; cowpea was less liked, while cleome was least liked. CONCLUSIONS : Canned amaranth leaves have potential as a commercial product that may be well liked by young consumers. The cowpea leaves product has consumer potential, but the formulation needs revision, while canned cleome leaves need further research work.http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1097-00102019-04-05hj2018Food Scienc

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

Workshop summary : consumer sensory research in Africa – the African countries profiles project

A workshop, organized by the Africa Network for Sensory Evaluation Research (ANSWER), was presented during the virtual 14th Pangborn Symposium in August 2021. The purpose of the 60 min workshop was to introduce ANSWER’s African Countries Profiles (ACP) project to the global sensory community. The long-term ACP project aims to leverage research about the sensory properties of products on the continent by highlighting opportunities and challenges when planning and conducting consumer research in African countries. A link to the open-access online “Guidelines for planning consumer testing in African countries” publication was made available to participants prior to the meeting. During the workshop a brief introduction of the ACP project and a case study featuring consumer testing in Ethiopia was presented. Workshop participants joined one of four online meeting rooms where different topics were discussed. The workshop concluded with a short feedback session in the main room and closing. The workshop provided an opportunity to identify the value and limitations/gaps of the information in the guideline document in order to optimise the ACP information and develop the discipline of Sensory and Consumer Science on the African continent.https://www.elsevier.com/locate/foodqual2023-02-26hj2022Consumer ScienceFood Scienc