New Research Projects

Developing soybeans as a modern food commodity

Dr H Schönfeldt
University of Pretoria

Aim

A review of the South African soybean industry along with the supply and demand of soya in the South African market.

The South African Soya Bean Industry

South African soya bean production reached an all-time high in 2016 of 1.3 million tons. With most of the staple agriculture crops experiencing a decline in production after the drought during the 2015/2016 production year, the soya market proved to be resilient through this time delivering a record breaking crop. Furthermore, the increase in return on investment received from soya compared to maize during this time has made this crop appealing for farmers. This is in conjunction with the increase in crushing capacity of soya for oil and oil cakes. However, this increase was fuelled by the soya crops ability to perform better in dry land conditions than maize during periods of drought and the production levels are expected to stabilise back to normal in the coming production year (BFAP, 2017).

Apart from the unstable markets due to the drought over the last three years it is expected that soya production will increase at an annual rate of 5%, reaching an estimated production of a million hectares in 2025. This increase is however not expected to fulfil the needs of the consumer market but assist the growing need for animal feed. Apart from an increase in production an increase in crushing capacity has also occurred over the past five years (BFAP, 2016). This crushing capacity can still not be fulfilled by local production, only supplying one third of the demand. In the 2015/2016 production year oil cake requirements reached 1.5 million tons of which 55% needed to be imported (Sihlobo & Kapuye, 2017).

By comparison the European Union (EU) produces an average of 1 million tonnes of soya each year, which is similar to that produced in South Africa. Furthermore, the EU imports an estimated 35 million tonnes each year which is mainly used for animal feed. However, the amount of soya that is currently needed by the EU cannot be locally produced due to a lack of available land and it is predicted that imports will continue to rise (WWF, 2017).

The South African soya bean market has three main legs which utilize soya in variety of ways. Soya oil and oil cakes comprise 32%, animal feed (which is most commonly for broiler and laying chickens) 60% and only 8% for human consumption and the food industry (Figure 1 and 2). Globally 85% of total soya produced is used by the crushing industry for the production of meal or oil for human and animal use (Soya Tech, 2017). South African soya production takes place over all nine provinces with Mpumalanga producing the largest share at 50% followed by the Free State with 22% (DAFF, 2016). Even though soya is produced in all nine provinces, favourable weather conditions in areas such as Mpumalanga and the Free State favour growth over other regions such as the Western and Eastern Cape (Dlamini, et al., 2013). Although a very small percentage of soya production is utilized by the food industry it plays a crucial role in the production of a variety of food stuffs.

The proportion of locally produced soya used for human consumption varies vastly over the years measured, 1980-2016 (Table 2) and is mostly influenced by the crushing industry. As only a small fraction of the crop is used for human consumption, this sector does not enjoy priority crop allocation shares. Between 2010-2015 139 837 tons of locally produced soya was used for human consumption which is thus far the highest measured value for a five year period (DAFF, 2016).

Literature on the consumption of soya in either its original form or as a processed product is scare. A study conducted America in 2006 stated that human consumption of soya is minimal with only 2% of soya protein derivatives used for human consumption, the rest being used for animal feed and crushing (Barrett, 2006). There is conflicting evidence on the actual percentage of the crop used for human consumption. Global figures range between 6% (Soya Tech, 2017), which states as being directly used for human consumption, to 25% of the crop used for human purposes, which included oil usage (WWF Global, 2017). It is projected that 85% of the crop is processed into meal and oil with the majority going to animal feed. An estimated 2% of the meal is processed into soy flour for human consumption and 95% of the oil is used in the food processing industry (Soya Tech, 2017).

The use of soybean oil by the food industry has increased over the last 30 years with producers realising the potential of the product in a variety of processed goods, such as margarine, mayonnaise, salad dressing and frozen products. After palm oil (35%), soybean oil is the second most commonly consumed oil (29%) trailed by rapeseed oil at 15% and sunflower oil which holds a mere 9% of the market share (STATISTA, 2017).

The most common uses of soya in the food industry is still for traditional products such as tofu and soymilk with 20th century innovations becoming more prevalent. Soya derivatives such as lecithin is a key ingredient in the food processing industry and the popularity of soya as an ingredient in meat products and even as a meat analogues is rising steadily. The diversity of the product is motivating research on the development of soya based products through the different food groups. The products versatility allows it to be grinded, milled, fermented, boiled and baked to name a few, whilst delivering textural characteristics that are pleasing to the consumer market at a fraction of the cost (Soya Tech, 2017).

According to data gathered from the National Development Plan and the Bureau of Food and Agricultural Policy, soya is an agricultural commodity that has a high potential for growth which is further promoted by its low labour intensity (Figure 3) (BFAP, 2011). With a rise in the cost of unskilled labour, especially in the agricultural sector, low labour intense crops are becoming more and more appealing (BFAP, 2017). This along with water use efficiency of the crop, especially in drought stricken areas, further increases the return of investment potential of the crop. This will be discussed in more detail in the soya and sustainable agriculture section.

The South African Consumer

A projected world population of 9.5 billion people by 2050 places pressure on the global food and agricultural sector to produce sufficient and nutritious food for all. The demand for protein as a macronutrient providing energy and essential amino acids will continue to increase along with the growing population. In addition, pressure is being placed on the food system to be more environmentally conscious (Drewnowski, et al., 2015). Although globally considered a healthy, sustainable, protein-alternative to animal-source foods, soybeans for human consumption have not been mainstreamed within South Africa.

The South African consumer is divided into four expenditure deciles i.e. marginalised, lower middle-income, upper middle-income and upper income. Income and expenditure vary over these groups along with the types of products they spend their money on (Figure 4). The marginalised and lower middle-income groups spend the biggest portion of their food expenditure on staple foods. Of these staple foods the dominant staple foods in order of importance are maize meal, brown bread, rice, white bread and potatoes. On the other side of the spectrum the wealthiest consumers have different preferences in order of importance for staple foods: brown bread, white bread, rice, maize meal and potatoes. Consumption patterns for these different groups vary over all the food groups with prices being one of the biggest discriminating factors (StatsSA, 2016; StatsSA, 2010/2011). Food affordability is one of the main concerns for South African consumers and guides many food choices with marginalised consumers spending about 34% of their total food expenditure on staple foods (BFAP, 2016).

Rising incomes in households have led to an increase in the consumption of protein products such as meat, eggs and dairy in South African food basket. Due to its low price in comparison to other meat products, the consumption of chicken meat enjoys the largest share. Consumption of different protein products vary over the different income groups. Marginalised consumers spend 25% of their household expenditure of food on meat, and 8% on eggs and dairy. The middle group spend 30% on meat, which includes, red and white meat, and 10% of dairy and eggs. The affluent group spends 33% of their total expendable food income on meat and 12% on dairy and eggs. From this data it is clear that the more affluent household spend more money on protein foods (BFAP, 2017). The South African Income and Expenditure Survey groups soya with the vegetable group making it difficult to determine the value of the food buying patterns of soya by the different income groups (StatsSA/IES, 2012).

Unfavourable consumer aspects of soya

Certain features of soya beans make them unfavourable in the consumer market, aspects such asflatulence (Suarez & Springfield, 1999), their beany taste (Bringe, 2015), tough skin and long cooking time (Barrett, 2006). Product development actions since the 1980's have attempted to address these problems by making the product more accessible to the general market as well as reducing or eliminating the negative effects of soya through processing (Rackis, 1981). These new approaches to soya processing and consumption can increase the acceptability and usage of the product (Tu, et al., 2012). However, marketing and consumer education campaigns are also required to communicate the appealing characteristics of soya to the consumer (Wansink, et al., 2000).

The South African school feeding scheme

The South African National School Nutrition Programme (NSNP) aims to feed 9.4milion children 5 days a week. The NSNP uses soya as an important protein source. Guidelines for the NSNP state that soya or soya mince can form part of the menu two times a week in most of the provinces (Department of Basic Education, 2017). Soy is served along with a variety of dishes such as maize and rice; as a soya mince stew with potatoes and carrots; samp and soya mince stew with potatoes and pumpkin. The last two options are the most popularly prepared dishes (Nhlapo, et al., 2015).

Soya served in the school feeding programme has to comply with a strict set of guidelines stipulated in Box 1. There is also a list of approved suppliers from which the soya has to be sourced, these suppliers are chosen based on their certificates of compliance, sensory evaluation, packaging and labelling (Department of Basic Education, 2017).

The consumption of soya in early childhood can form the basis for livelong soya consumption principals. However, a review on the NSNP conducted in 2015 found that this is not the case. The report states that "learners indicate that they do not enjoy the soya". This is in conjunction to research findings stating that only 3.4% of schools within the school feeding programme serve adequate amounts of protein. Soya is one of the most commonly used protein rich foods served in the NSNP. It was found that learners refuse to eat the meals on days when soya is served. Not only does this lead to wastage of food but also low protein consumption rates for these learners. This is problematic as soya minces features quite prominently on the provincial menus. There is a two tailed recommendation to solving this problem; firstly industry at a primary level can implement ways of making soya more acceptable to the consumer; secondly it is proposed that cooking techniques be adapted and serving the soya in a manner that learners will find appealing (Department of Basic Education, 2015).

Nutritional value of soya

The soya bean consists of 40% protein, 20%-30% carbohydrates, 18% oil and the rest moisture and ash (Wolmarans, et al., 2010) (Table 3). One of the main appeals of soya is its role of protein replacement along with its ability to be processed to have a meat like consistency, as well as, acting as a natural emulsifier in the food and processing industry (Food Insight, 2017).

Plant-based foods have been a source of protein for humans for millennia, providing about 2/3 of total protein intake globally. In South Africa, however, the intake of legumes and pulses, including soybeans, has not been prioritized. Although one of the South African Food-Based Dietary Guidelines of the National Department of Health states that adults and children older than 10 years should 'Eat dry beans, peas, lentils and soy regularly', only 4% of total production in 2012 was processed for human consumption (DAFF, 2016). Although this contribution is small compared to oilcakes or animal feed, the human consumption of soybeans have increased 5-fold since the early 1980s, indicating a potential to grow and establish this commodity as a modern, healthy, culinary item. The total South African soya bean crop is estimated to be about a million tons in the 2016/2017 production year, which is only 0.28% of global production (Global Soybean Production, 2017). This will need to be supplemented by a further 1.5 million tons of imported soya to fulfil the need currently experienced (Department of Agriculture, Forestry and Fishery, 2010; Department of Agriculture, Forestry and Fishery, 2015; Sihlobo & Kapuye, 2017).

The WHO Technical Report on Protein and Amino Acid Requirements in Human Nutrition (2007) states that the best estimate for a population average requirement is 105mg nitrogen/kg body weight per day, or 0.66g protein/kg body weight per day. In many developing countries protein intake falls significantly short of these values. Apart from protein quantity, protein quality including bioavailability and digestibility, from different food sources, is currently being discussed on the global nutrition agenda. The 1st International Symposium on Dietary Protein for Human Health held in Auckland, in March 2011, and the follow-up Food and Agricultural Organization of the United Nations (FAO) Expert Consultation on Protein Requirements, both highlighted the importance of assessing the quality of protein from different food sources through the determination of amino acid content. Throughout the developed world, animal products and cereals are the two most important sources of protein, respectively. In developing countries such as South Africa, this order is reversed (Layman, 2009). In low income countries only 3% of total dietary energy as an indicator of diet composition, is derived from meat and offal, 11% from roots and tubers and 6% from pulses, nuts and oilseeds. The remainder of the dietary energy is mainly obtained from cereal based staple foods. Although the production of livestock has increased in developing countries, the consumption of protein in these countries is continually decreasing. Undernutrition, including insufficient consumption of protein, remains a persistent problem in developing communities, and although many diets within these communities are deficient in the quantity of protein compared to recommendations, the quality of the protein is as important (Schönfeldt & Hall, 2012; WHO, 2007).

* (Wolmarans, et al., 2010)
# (Department of Health, 2010)
– not determined / no value

In terms of protein quality for dietary adequacy, most plant proteins are considered to be "incomplete" in that they are deficient in one or more of the indispensable amino acids. Even though soya contains all the essential amino acids, which are required in order to be classified as a complete protein (Table 4), it does not contain these amino acids in the correct ratio due to plant products low methionine content (Clarke & Wiseman, 2000). Mixtures of different plant protein sources may be complementary, with one source providing the amino acid that is limiting in another source and viceversa, thereby making the mixture of plant proteins "complete" sources of amino acids. Dietary approaches that combine complimentary foods, i.e. a cereal and a legume such as maize and soybeans, will meet protein requirements. Establishing a baseline on the nutritional profile of current cultivars is thus essential for future prioritization for improvement of nutritional profile. Translating the knowledge on the nutritional profile of soybeans into such tangible recommendations to meet dietary needs is also needed (Kumar, et al., 2015). Table 5 shows the differences in lysine, methionine and cysteine content of several food stuffs. Some amino acids commonly limit the nutritive value of different sources of proteins in the human diet, these are methionine, lysine, tryptophan and threonine. These amino acid concentrations are generally lower in plant based sources of protein. Even though animal-based foods contain all essential amino acids in the correct proportions the correct combination of plant-based protein foods could increase the protein quality of the meal (Table 6).

Soya and sustainable agriculture

Since sustainable resource use has come under the spotlight, researchers have been examining whether it is possible to feed a growing global population while preserving the environment. The ever growing pressure on industry to decrease emission and contribute to sustainable agriculture has proven to be challenging. Therefore, crops that provide high nutrient dense foods are placed under the spotlight in conjunction with their greenhouse gas emission rates. The availability of an index to provide industry with a holistic view of their product ensures a proactive rather than defensive position is taken and can lead to increase marketing potential as well as a driver behind policy and programme adaptation (Drewnowski, et al., 2015). Further details on the effect of soya on environmental resources will be discussed below with a proposal for South African data on the topic in the recommendations section.

Products / ingredients

A market investigation proved that soya is a widely used product in a variety of foodstuffs (Figure 5). A few supermarkets in rural and urban areas along with health shops and smaller retailers were investigated to better determine the availability and uses of soya in the common retail arena. During these investigations it was found that soya is an added product or ingredient in numerous food items over all the different groups due to its functionality for improving shelf life.

For rural areas, a spaza shop in Cullinan was investigated. It was found that at these types of establishments' soya is mainly only present in processed products and soya mince. Soya was not, as expected, sold whole in a dried format in this shop.

Secondly two large supermarkets were surveyed in the north of Pretoria. From this investigation it was found that soya is once again most commonly found in a processed and baked goods. Due to the larger size of the store there were more soya containing products. During this part of the study it became evident that soya is an essential part of the food processing industry on many levels due to all the functional properties it plays in a variety of products (Table 7). Soya in all of its different forms was found in all the different sections of the supermarket. It was also noted that when moving closer to urban areas the availability of soya based meat alternatives in the form of sausages, patties, curries and "chicken fillets" available as readymade meals were noted.

Moving into urban areas where there are a variety of large retailers to choose from, certain interesting findings were made. Soya became more prevalent in its original unprocessed form. Items such as canned soya beans in brine, frozen edamame beans and fresh edamame beans were observed i.e. in fresh salads as well as canned. Edamame beans are becoming a trendy salad option being used in fresh readymade meals. It was also noted that there is a larger variety of brands that supply soya based meat alternatives and readymade meals in these urban areas.

Edamame, which refers more to the original method of steaming soya beans in the pod, is the immature soya bean pod that can either be consumed as is with the pod or as the beans removed from the pod. These beans can be consumed raw, which is most commonly seen in salads or steamed whole in the pod served with some form of dipping sauce. The beans have a bright vivid green colour and crunchy texture, when served raw. The vivid appearance, nutritional potential and appealing texture as a salad ingredient can be some of the reasons for the increase in demand for the product and the occurrence of the bean on South African shelves. Retailers and farmers in America has noted a 10% year on year growth in the demand for edamame beans since 2001 when it was main streamed in the consumer market (Shurtleff & Aoyagi, 2009) (Figure 6-7).

One of the most common and probably well-known soya products in South Africa, soya mince, was readily available in a variety of flavours and sizes at all of the stores visited. Soya milk and sauce was also a commonly available product in all the different retail outlets.

Health shops were visited, where the researchers expected to find a wide variety of soya products including whole soya. On the contrary, upon investigation it was found that health and wellness shops mostly stock soya protein powder, soya milk powder and soya flour. The shop manager at a well-known health shop stated that soya is not regularly requested by consumers and their most sold soya item is the protein powder. It was also found that soya is marketed as a common snack food by health and wellness companies as a replacement for fried snack foods.

The versatility of the product allows it to be used by more than just the food and wellness sector and soya can be found in a variety of cosmetics. Soya derivatives can be found in make-up, soaps, craft materials; such as glues and glycerine. The different industries use different parts of the soya bean to achieve a variety of outcomes as seen in Figure 5 (WWF, 2017).

An international cosmetic company, which is also the leader in handmade cosmetics, has begun experimenting and incorporating soya oil into its products. They use the oil that is processed from the shelled seeds which delivers a bright, pale liquid. The beauty benefits are said to be derived from the high content of linoleic (omega-6) and oleic (omega-9) acids as well as small amounts of linolenic (omega-3) and saturated fatty acids. The soya oil is used in hair, nail and body creams. Soya milk is also used in bath creams and hair masks as it contains B vitamins and is said to have an antioxidant effect on the skin. Lecithin is known for its emulsifying effect. This emulsifying effect is demanded by the cosmetics sector when creating products containing unstable ingredients which do not naturally emulsify (LUSH, 2017; Cosmetic Info, 2017).

Consumer survey

An electronic survey was constructed on Survey Monkey to get a basic idea of consumer perceptions and knowledge on soya. The survey consisted of ten questions including basic demographic questions including age, gender and race.

Respondents to this survey were aged between 18 and 80 years. The majority of respondents fell in the age category 25-34 (28), followed by 55-65 (22) (Figure 20). Of the 100 respondents 87 were white, 5 black, 1 coloured and 7 preferred not to disclose their race. Responses was split 50/50.

In this study it was found that 54% of respondents consume soya 'sometimes'. Furthermore, 17% of respondents stated that they never consume soya (Figure 21). A research study conducted in America between 2010 and 2014 among 1 000 consumers found that consumers reported consuming soya once or more a week rose by 7% during this time (STATISTA, 2017).

In Figure 22, respondents could choose multiple responses. This question was based on the market survey conducted on soya derivatives available in foods. For this question the correct answer was 'All' as all of the foods listed contains some form of soya. Only 27 respondents answered this correctly?

When asked how often soya can be consumed 68% of respondents said daily and only 2% never. These results can act as motivation for consumer education on the product as 19% of the respondents did not know how often soya can be consumed (Figure 23).

When asked whether soya is a high protein food that can form part of a healthy diet 87% of respondents agreed, 5% disagreed and 8% did not know (Figure 24).

A survey conducted by the America Soy Board in 2016 showed that 54% of consumers did not change their opinion about the healthfulness of protein from plant sources despite marketing efforts (STATISTA, 2017). It appears that consumers in this study already have a positive feeling towards the role of soya in a healthy diet which can be further supported by consumer education campaigns.

Respondents were asked whether they believe soya is a poor man's food, 81% disagreed with the statement while 19% agreed.

When asked to state the reason why they do not eat soya 17% of the respondents stated it is because it has a funny taste, 13% said they don't like it and 10% do not eat it because they don't know how to cook it (Figure 25).

Respondents to this survey stated that they would be more likely to consume soya if there were easy and delicious recipes available. This statement goes hand in hand with the 14% who said they would be more likely to consume soya if it was readily available and if they knew how to cook it. Only 11% of respondents stated that they will not be convinced to eat soya (Figure 26).

Upon investigation it was found that soya is found in a vast variety of products available on the South African market and plays a cardinal role in the food processing industry. However, data on the usage, price and consumption rate of soya as a food product is limited. The most commonly used sources for data on usage, price, production and prediction include the Bureau for Food and Agricultural Policy (BFAP), the National Agricultural Marketing Council, STATS SA, Income and Expenditure Survey and the National Food Consumption Survey, to name a few. However, these sources contain little to no information on soya for human consumption. Copious amounts of research is available on the use of soya in animal feeding and to some extent the edible oils industry as a spinoff of animal feed. The lack of data is presumed to be due to low consumption rates. This may be a starting point for future projects to disseminate data on the variety of uses of soya in order to create a holistic view of the product as it is used and consumed in the different sectors, especially for processing.

Conclusions and recommendations

Soya can play a functional role in the human diet. The high protein content of soya further aids nutrition in a country were protein energy malnutrition is prevalent. However, the taste of certain soya products are unappealing to the general consumer, as seen in the NSNP. These aspects can be addressed by primary industry with the development of soya products that are more appealing to the palette. Initiatives can also be made by industry role players to develop consumer education campaigns and recipes that address the issues identified in the questionnaire, such as consumers having a need for easy and delicious recipes that contain soya.

It is recommended that consumer education campaigns focus on highlighting the role that soya can play in the diet along with recipe development for different consumer market segments. Furthermore, an extensive data gathering initiative can be launched in order to get a better understanding of the use of soya for human consumption in a processed as well as original form.

Current nutritional values for soya listed in the South African Food Composition Tables, which are the tables used to make dietary recommendations, are based on values borrowed from the Unite States Department of Agriculture. This needs to be addressed as previous studies on various products found that the nutritional values of agricultural products can differ significantly between countries. Therefore it is recommended that nutritional analysis on South African soya be conducted to ensure these values represent the local product.

To ensure South Africa is on par with the Food and Agricultural Organization of the United Nations (FAO) Expert Consultation on Protein Requirements it is strongly recommended that a study be conducted on the amino acid profile of locally produced soya beans. This will ensure policies and programmes of agriculture and nutrition in the country is based on relevant research on local products.

Lastly it is recommended that a sustainability index be developed for legumes and pulses. Since sustainable resource use has come under the spotlight, researchers have been examining whether it is possible to feed a growing global population while preserving the environment. A sustainability index takes the nutrient density as well as the carbon emission of the product into account in order to predict which products emits the least amount of carbon in comparison to the nutrients it contributes to the diet. Such an index will assist industry in the implementation of policies and programmes as well as assisting in marketing endeavours and consumer education campaigns.

Project to determine groundnut quality at moisture levels between 7% and 10% and the foreign matter weigh loss from 18% to 7%

Mr N Wegner
PPECB

A progress report regarding the project is still awaited.

Soy smallholder farmer needs assessment for farm training

Prof W Oldewage-Theron
Vaal University of Technology

Although a provision for the funding of the project was made the project will only commence during the 2018/2019 financial year.