Graduation date: 1992

The production, processing and marketing of sustainable and affordable food involve complex phenomena that affect the lives of millions of people worldwide. Due to the rapid growth of the world's population, the provision of food is a significant challenge for the agrifood industry and policy makers, as this is strictly interlinked with climate change and public health interventions. The overall aim of this research was to contribute to delivering nutritious food to feed an increasing unhealthy population. High-protein crops that can be grown sustainably in high latitude countries, including Scotland, could provide a healthy alternative to partially replace our dependency on unsustainable protein-rich foodstuffs. These include meat, the production of which is responsible for a substantial share of food-related environmental pressures. For this reason, green pea, lupin, fava bean, hemp and buckwheat were selected and analysed for their macro- and micro- nutrient content, as well as their phytochemical profile and compared to a red meat- and wheat-based meal in a human intervention trial. The crops studied were high in protein (ranging from 20 to 43% in buckwheat and lupin, respectively) and fibre (up to 25% in hemp) and also found to contain a diverse range of phenolic compounds, considered to participate in the prevention of diet-related disorders. As fava bean contained relatively high amounts of protein (approx. 22% w/w), protein fractions were isolated and further investigated to understand the contribution of the phytochemical components in terms of protein functionality and oxidative stability. Since fava bean protein isolates showed promising food applications, they were used to develop meat patties. The addition of fava bean proteins significantly decreased lipid and protein oxidation of the processed products. The results of this research could encourage a higher consumption of plant-based products, which would be favourable from both a health and environmental perspective.

A fifteen day balance study was conducted to test the value of two diets providing 24 and 16 gm. of plant-protein daily and to approach the approximate minimum protein requirement using plant proteins for a 23-month old Chinese girl weighing 12 kg. The diets were supplemented to bring nutrients to the NRC recommended allowances except for protein and calories. Essential amino acids were planned to approximate the FAO provisional pattern. Nitrogen determinations were made on food, urine and feces. Food composites for each diet were analyzed for nine of the essential amino acids using a Beckman/Spince Model 120 Amino Acid Analyzer. Tryptophan was determined by microbiological assay. Nitrogen in the diets averaged 3.96 and 2.69 gm. respectively for the two protein levels of 24 and 16 gm. daily with retention of 0.33 gm. daily for all periods, or 0.48 gm. and 0.44 gm. for the test periods. The essential amino acids as analyzed represent 59 per cent and 34 per eent of the total protein in the moderate and low protein diets. The analyzed amino acid patterns were as follows: tryptophan 1.0 and 1.0; threonine 2.8 and 2.2; isoleucine 5.8 and 3.5; leucine 9.4 and 5.5; lysine 3.1 and 3.7; methionine 1.2 and 0.8; phenylalanine 6.1 and 3.6; valine 6.7 and 3.9; arginine 4.4 and 4.5; and histidine 1.3 and 2.0. A positive nitrogen retention of better than 0.4 gm. daily (0.033 gm./kg.) was obtained with daily nitrogen intake of 0.33 and 0.22 gm. per kg. of body weight for this 23-month old girl with approximately 90 and 84 calories per kg. per day. / Master of Science

We investigated the effect of pyridoxine supplementation on the utilization of protein in a low-protein, plant-based diet in four subjects (2 men and 2 women), aged 21 to 38 years. Following two days of a negligible protein diet, this 34 day study was divided into three dietary periods: the subjects received a low-protein, plant-based diet during period I for 10 days (no pyridoxine supplement), the same diet but with the addition of 50 mg pyridoxine HCl during period II for 7 days, and their self-chosen diets during period III for 15 days (no pyridoxine supplement). Data for period III will be reported elsewhere. The greatest portion of protein in the experimental diet was furnished by pinto beans (1.02 g nitrogen) and peanut butter (0.86 g nitrogen); nitrogen intake was kept constant at 4.56 g/d for the men and 4.15 g/d for the women during periods I and II. These diets administered during periods I and II provided 0.907 mg of vitamin B-6 for the men and 0.758 mg of vitamin B-6 for the women and was adequate in other nutrients except for protein. Overall, the effect of 50 mg pyridoxine HC1 supplementation on the utilization of protein in a low-protein plant-based diet was not statistically significant (p > 0.05) on the basis of a paired t-test for the parameters measured: nitrogen balance, apparent protein digestibility, as well as plasma and urinary urea nitrogen. Furthermore, we obtained conflicting results, when the subjects received pyridoxine, their plasma urea nitrogen increased slightly (suggesting increased protein degradation), while the percent of total urinary nitrogen excretion as urea nitrogen decreased (suggesting decreased protein degradation). These changes were not statistically significant, but limitations in the nitrogen balance technique and the analytical procedures we used may have contributed to these conflicting results. We suggest that a longer study with more subjects may show a greater improvement of plant protein utilization than we had observed. / Graduation date: 1990

The purpose of this study was to explore the influence of external product attributes on consumers’ perceived acceptance of pea protein as a protein substitute in food products. The interest in pea protein as a possible protein source was investigated and the various advantages of consuming pea protein were highlighted. In previous studies, pea protein was identified as a possible substitute for red meat (Davies & Lightowler, 1998), but also as protein containing the amino acid profile which corresponds with the profile recommended for adults by the Food and Agriculture Organisation (FAO) (Swendseid, 1981). Additionally the nutritional and health benefits, the environmental benefits of growing pea protein as well as the non-allergen declaration accompanying pea protein were discussed. The various factors that will influence the consumer’s decision making process when introduced to a new and unfamiliar protein source such as pea protein were investigated in terms of the external product attributes as well as the factors indicated in the Theory of Reasoned Action (TRA) (Fishbein & Ajzen, 1975). The external product attributes were identified as the influence of price, marketing of the product, packaging attributes of new food products, branding importance of a product and new product education and knowledge perceived necessary for acceptability of a new food product. The additional factors which were investigated, as indicated by the TRA, included the influence of the subjective norms or significant others, as well as the consumers’ personal attitude. attitude. Due to the limited insight and understanding of the influences that external product attributes have on a consumer’s perceived acceptance of pea protein as a protein substitute in food products, a qualitative exploratory research design was initiated. An exploratory research design was incorporated because this afforded the researcher the opportunity to gather thorough and comprehensive data or information and it also increased the richness and depth of explorations that could be researched (Key, 2002). The fact that an exploratory research design was incorporated, a non-probability sampling strategy was implemented. Additionally a convenient sampling strategy was also implemented because this type of sampling strategy represents sites or individuals from which data can easily be collected and where access is convenient (Cresswell, 2007). The unit of analysis for this research was female shoppers, being the main grocery and food shoppers in the household, who were living in suburban areas. The participants of the research, therefore, resided mainly in the Johannesburg and Pretoria suburban areas, within the Gauteng province and were chosen because these are two of the major suburban cities in South Africa. The data were collected through means of a multi-method approach whereby different data collection instruments were applied. In this regard focus group interviews, sentence completion exercise and a vignette were used which addressed the objectives set out in the study. From the findings of the study on the influence of external product attributes on consumers’ perceived acceptance of new products in general and new products containing pea protein, it was found that there were not any noticeable differences between a new food product and a new food product containing pea protein. The consumer did not indicate a greater willingness to accept general new products in comparison to a pea protein product. On the contrary, the fact that a new product contained pea protein did not make any difference. For consumers external product attributes in general played a major role in their purchasing decision making process. The most important requirement that the consumers had was that additional information regarding the pea protein should be provided. It was indicated by the participants that they would be interested in the pea protein product and consider purchasing it and incorporating it into their daily diet, providing they knew more about the product and had sufficient background information about the new product. Furthermore, the importance of marketing of a new product was highlighted and the fact that the packaging of the new product should be attractive and eye-catching. Price competiveness was mentioned, however, should a new and unfamiliar product be introduced by a well-known brand, this would lower the initial resistance to the new product. One of the main limitations of this study is the relatively small sample size from a particular area in South Africa and, therefore, resulting in a very selective sample. The sample, therefore, remains one of convenience which limits the ability to generalize or transfer findings to a bigger group of consumers. Furthermore the study location was within a limited area, namely Gauteng. For this reason no assumptions were made nor were findings considered to be transferable to other population groups or consumer groups. Another limitation is that the topic of this study is very new and unfamiliar; there are, therefore, no previous studies with which to compare the findings. This study was exploratory in nature and the instruments were chosen specifically to explore a new and unfamiliar topic. The transferability of this study might be limited, but care was taken to describe the research context in as much detail as possible. In doing so, an attempt was made to enhance the transferability, should another researcher wish to duplicate the study. From the findings of this study certain recommendation can be made as most participants were of the opinion that they would be interested in the pea protein product and consider purchasing it and incorporating it into their daily diet provided they knew more about the product and sufficient background information had been supplied. Furthermore, it was noted from the findings that these external attributes would influence the new product acceptability and, therefore, giving the research and developers as well as the marketing team of a manufacturing company the information necessary to understand the requirements from the consumers regarding the product containing pea protein better and how this product should be marketed as a healthy alternative to other vegetable protein sources. Further recommendations are that should a food manufacturing company wish to develop a pea protein product, they would need to promote the product beforehand and create an awareness of the advantages and benefits of pea proteins. This can be done by editorials in magazines as well as promotions in printed media. Additionally, the competition between products and brands is fierce and, therefore, manufacturing companies need to differentiate their products to keep consumers interested in their product or brand. Pea protein is a new and innovative product and can, therefore, add that differentiation and benefit to food products. Future research that can be considered is that of a sensory study, to determine the actual viability of the pea protein products based on sensory evaluation. One of the main criteria indicated for the acceptability of a food product containing pea protein has been the taste. The present research was theoretical and exploratory in nature and, therefore, there were no actual products which the participants could taste. Additionally, the inclusion criteria for this study was identified as female shoppers who are in charge of household grocery and food purchases and were, therefore, specifically recruited to participate in the research. However, based on a study done by Jensen (2011), it is recommended that further studies specifically include males because men are doing more of the household grocery shopping and they are not as brand loyal as females and would, therefore, be more willing to try and experiment with new food products. A study based on the gender differences of the acceptability of new products, could highlight different extrinsic attributes that would influence the purchasing decision. / Business Management / M. Consumer Sc.

The purpose of this study was to explore the influence of external product attributes on consumers’ perceived acceptance of pea protein as a protein substitute in food products. The interest in pea protein as a possible protein source was investigated and the various advantages of consuming pea protein were highlighted. In previous studies, pea protein was identified as a possible substitute for red meat (Davies & Lightowler, 1998), but also as protein containing the amino acid profile which corresponds with the profile recommended for adults by the Food and Agriculture Organisation (FAO) (Swendseid, 1981). Additionally the nutritional and health benefits, the environmental benefits of growing pea protein as well as the non-allergen declaration accompanying pea protein were discussed. The various factors that will influence the consumer’s decision making process when introduced to a new and unfamiliar protein source such as pea protein were investigated in terms of the external product attributes as well as the factors indicated in the Theory of Reasoned Action (TRA) (Fishbein & Ajzen, 1975). The external product attributes were identified as the influence of price, marketing of the product, packaging attributes of new food products, branding importance of a product and new product education and knowledge perceived necessary for acceptability of a new food product. The additional factors which were investigated, as indicated by the TRA, included the influence of the subjective norms or significant others, as well as the consumers’ personal attitude. attitude. Due to the limited insight and understanding of the influences that external product attributes have on a consumer’s perceived acceptance of pea protein as a protein substitute in food products, a qualitative exploratory research design was initiated. An exploratory research design was incorporated because this afforded the researcher the opportunity to gather thorough and comprehensive data or information and it also increased the richness and depth of explorations that could be researched (Key, 2002). The fact that an exploratory research design was incorporated, a non-probability sampling strategy was implemented. Additionally a convenient sampling strategy was also implemented because this type of sampling strategy represents sites or individuals from which data can easily be collected and where access is convenient (Cresswell, 2007). The unit of analysis for this research was female shoppers, being the main grocery and food shoppers in the household, who were living in suburban areas. The participants of the research, therefore, resided mainly in the Johannesburg and Pretoria suburban areas, within the Gauteng province and were chosen because these are two of the major suburban cities in South Africa. The data were collected through means of a multi-method approach whereby different data collection instruments were applied. In this regard focus group interviews, sentence completion exercise and a vignette were used which addressed the objectives set out in the study. From the findings of the study on the influence of external product attributes on consumers’ perceived acceptance of new products in general and new products containing pea protein, it was found that there were not any noticeable differences between a new food product and a new food product containing pea protein. The consumer did not indicate a greater willingness to accept general new products in comparison to a pea protein product. On the contrary, the fact that a new product contained pea protein did not make any difference. For consumers external product attributes in general played a major role in their purchasing decision making process. The most important requirement that the consumers had was that additional information regarding the pea protein should be provided. It was indicated by the participants that they would be interested in the pea protein product and consider purchasing it and incorporating it into their daily diet, providing they knew more about the product and had sufficient background information about the new product. Furthermore, the importance of marketing of a new product was highlighted and the fact that the packaging of the new product should be attractive and eye-catching. Price competiveness was mentioned, however, should a new and unfamiliar product be introduced by a well-known brand, this would lower the initial resistance to the new product. One of the main limitations of this study is the relatively small sample size from a particular area in South Africa and, therefore, resulting in a very selective sample. The sample, therefore, remains one of convenience which limits the ability to generalize or transfer findings to a bigger group of consumers. Furthermore the study location was within a limited area, namely Gauteng. For this reason no assumptions were made nor were findings considered to be transferable to other population groups or consumer groups. Another limitation is that the topic of this study is very new and unfamiliar; there are, therefore, no previous studies with which to compare the findings. This study was exploratory in nature and the instruments were chosen specifically to explore a new and unfamiliar topic. The transferability of this study might be limited, but care was taken to describe the research context in as much detail as possible. In doing so, an attempt was made to enhance the transferability, should another researcher wish to duplicate the study. From the findings of this study certain recommendation can be made as most participants were of the opinion that they would be interested in the pea protein product and consider purchasing it and incorporating it into their daily diet provided they knew more about the product and sufficient background information had been supplied. Furthermore, it was noted from the findings that these external attributes would influence the new product acceptability and, therefore, giving the research and developers as well as the marketing team of a manufacturing company the information necessary to understand the requirements from the consumers regarding the product containing pea protein better and how this product should be marketed as a healthy alternative to other vegetable protein sources. Further recommendations are that should a food manufacturing company wish to develop a pea protein product, they would need to promote the product beforehand and create an awareness of the advantages and benefits of pea proteins. This can be done by editorials in magazines as well as promotions in printed media. Additionally, the competition between products and brands is fierce and, therefore, manufacturing companies need to differentiate their products to keep consumers interested in their product or brand. Pea protein is a new and innovative product and can, therefore, add that differentiation and benefit to food products. Future research that can be considered is that of a sensory study, to determine the actual viability of the pea protein products based on sensory evaluation. One of the main criteria indicated for the acceptability of a food product containing pea protein has been the taste. The present research was theoretical and exploratory in nature and, therefore, there were no actual products which the participants could taste. Additionally, the inclusion criteria for this study was identified as female shoppers who are in charge of household grocery and food purchases and were, therefore, specifically recruited to participate in the research. However, based on a study done by Jensen (2011), it is recommended that further studies specifically include males because men are doing more of the household grocery shopping and they are not as brand loyal as females and would, therefore, be more willing to try and experiment with new food products. A study based on the gender differences of the acceptability of new products, could highlight different extrinsic attributes that would influence the purchasing decision. / Business Management / M. Consumer Sc.