Overcoming barriers to sustainable, healthy diets

Abstract

Food Science and TechnologyVolume 36, Issue 1 p. 40-45 FeaturesFree Access Overcoming barriers to sustainable, healthy diets First published: 13 March 2022 https://doi.org/10.1002/fsat.3601_11.xAboutSectionsPDF ToolsExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Nicola Stanley, Casiana Blanca Villarino and Isabella Nyambayo of the IFST Sensory Science Group explore the barriers to consumption of more sustainable plant-based and alternative protein diets from a consumer perspective. Rising to the alternative protein challenge To meet United Nations global sustainable development targets, there is an urgent need to minimise the intensive resource requirements (e.g. water, feed, land) used in farming animals for food production and to reduce the associated high levels of greenhouse gas emissions. Consequently, the race is on to develop new, consumer acceptable, alternative protein foods with a clean label to replace meat and dairy products in our diets. Over the last few years, university scientists, government researchers, food industry product developers and ingredients experts have all been prioritising the development of alternative protein sources. This new world includes novel ingredients, such as insects, algal proteins and even lab-grown meat, as well as the more obvious contenders, such as legumes, cereals and fungi. Each differ in the quality of nutrition they provide based on the levels and types of macro and micro nutrients they contain. For example, insect-based foods are considered healthy due to superior nutritional profiles that are low in saturated fat and sugars, and high in unsaturated fatty acids, proteins, minerals and fibre. Sustainable meat analogues are being produced from these ingredients and developed to resemble the texture, mouth-feel, taste and nutritional qualities of meat. Ingredient transformations using processing technologies have also addressed the impact of visual appearance on food acceptance and food technologists continue to work on improving the functional and sensory properties of alternative protein sources and ingredients. Barriers that can prevent consumers from trying new protein sources will often be down to culture and tradition as well as anticipated sensory experience. Approaches to change consumption behaviour include working with consumers to create awareness through communications and education, and designing new products to fit into relevant occasions and lifestyles. Consumer acceptance of these alternative protein products will ultimately determine whether they are successful or not in the global marketplace. This article explores the roles of national governments and the food industry in encouraging consumers to buy, try and continue to purchase alternative protein products as part of a sustainable future. What foods and diets are good for people and the planet? A sustainable diet considers environmental, nutritional, social and economic factors. One of the most encompassing definitions was devised by the Food and Agriculture Organization (FAO) in 2010 (Figure 1). Figure 1Open in figure viewerPowerPoint Definition of sustainable diets (FAO 2010, Sustainable Diets and Biodiversity) Although this FAO definition includes some nutritional guidance, the actual description of a healthy diet requires further clarification and a number of nutritional profiling tools go some way to achieve this. These quantify and benchmark the nutritional adequacy of dietary intake. Some, such as the Health Diet Indicator (HDI), measure the adherence of a diet to specific dietary guidelines. Others, including Nutrient Rich Food (NRF9.3) and the SAIN:LIM index, relate to the overall balance of positive and negative nutritional impacts of a specific food product. There are also several measures that assess negative health risks of specific foods (Table 1). Table 1. Examples of models and indices relating to healthy and sustainable diets2 DIET BASED NUTRITIONAL MODELS PRODUCT BASED NUTRITIONAL ADEQUACY MODELS PRODUCT BASED NUTRITIONAL RISK FACTORS SUSTAINABILITY INDICES FOR FOODS Health Diet Indicator (HDI) – combines six nutrients (saturated fatty acids, polyunsaturated fatty acids, protein, dietary fibre, cholesterol and non-milk extrinsic sugar) with one food group (fruit and vegetables) Health Score (HS) Mediterranean diet quality index (Med-DQI) Diet Quality Index (DQI) Nutrient Rich Food (NRF9.3) – a score based on nine nutrients to encourage (protein, fibre, vitamins A, C, D and calcium, iron, potassium, magnesium and three nutrients to limit (saturated fat, added sugar, sodium) The SAIN:LIM index – defined as the ratio of five qualifying ‘healthy’ nutirents (ie protein, fibre, calcium, vitamin C and iron) and diqulaifying ‘unhealthy’ nutrients (eg saturated fatty acids and free sugars). Nutrient Profiling (NP) – a tool developed by the UK Food Standards Agency, to help UK communications regulator (Ofcom) differentiate foods high in fat, sugar and salt to improve the balance of television advertising to children towards healthier alternatives micro-Disability Adjusted Life Years (μDALY) – indicates the level of disease burden from consuming a gram of food (or nutrient) in terms of the amount of healthy life lost (in units of 1/1,000,000 of a year). Life Cycle Assessment (LCA) – a simulation methodology used to evaluate natural effects and impacts linked to all the phases in the life of a product from the obtaining of raw materials, processing of these materials, manufacturing, disemmination, usage, maintenace and repair and selling or reusing. Dialecte – a comprehensive tool cosisting of a rating system based on the principles of agroecology, integrated production and organic farming. It favours diversified farming systems, with high levels of biodiversity and systems adapted to local conditions and having abundant versus rare resources Barriers that can prevent consumers from trying new protein sources will often be down to culture and tradition as well as anticipated sensory experience. Researchers are increasingly working to model nutritional metrics with sustainability indices. For example, Masset et al.1 correlated greenhouse gas emissions with the nutritional quality SAIN:LIN index for different food categories. Overall, their results showed that foods causing the least greenhouse gas emissions were plant-based and tended to have higher nutritional quality and a relatively lower price per kilogram. There was not, however, such a straightforward conclusion when modelling price per kilocalorie. In this instance, foods with a lower energy density, such as fruit and vegetables, came out with comparatively low sustainability scores. Further research is required to harmonise approaches for modelling nutritional quality with sustainability placing more emphasis on overall diet rather than product category2. Encouraging consumer behavioural change Many governments have developed dietary guidelines for their nations. These are usually communicated in conceptual ways to create shared understanding amongst professionals, educators and the public. Overall, the overriding message is the need for a balanced and varied intake of macro and micro nutrients from across a range of food types. Often, these guidelines are communicated pictorially, in simple and effective campaigns, such as the well-known ‘Eatwell Plate’(UK) or the ‘Food Pyramid’. These models tend to vary in finer detail by country based on traditional diets and locally available food sources3. So far, only a few countries (e.g. Sweden and Brazil) have incorporated sustainability factors into their dietary guidelines. Several international organisations are leading the way in developing guidelines that combine sustainability considerations with nutrient intake. For example, World Wide Fund for Nature (WWF) has developed the ‘Livewell six principles’ for a healthy, sustainable life: 1) Eat more plants 2) Eat a variety of foods 3) Waste less food 4) Moderate your meat consumption (red and white) 5) Buy food that meets a credible certified standard 6) Eat fewer foods high in fat, salt and sugar4. Another example is the Double Pyramid5 developed by the Barilla Center for Food and Nutrition (BCFN). This accounts for the impact of food both on people's health and also the environment. Versions of the Double Pyramid are available for dietary guidance at a global level and for an increasing number of regions and countries (i.e. South Asia, Africa, United States). Consumer education and communication approaches such as these are being used to effectively raise awareness and change behaviours by nudging consumers towards more healthy and sustainable food choices. Taking one step further is the recent move towards including sustainability as well as nutritional indicators on product packaging. Indeed, studies6 have found that on-pack sustainability indicators lead to consumers purchasing more environmentally friendly products. Today, with the advent of on-pack ‘traffic light’ sustainability indicators, combined with the potential use of on-pack QR codes linking to smartphone applications, it is entirely possible to envisage a future with well-informed consumers using information at the point-of-sale to make more environmentally friendly and healthy food choices. With ever more proactive approaches to encourage consumers to decrease the animal-based components in their diets, not only are significant reductions in environmental impacts and decreased emissions anticipated, national governments are also expecting to reduce overall spending on national health and medical care. Taking all these considerable benefits into account, why in practice is it so difficult to change consumer behaviour? Overcoming socio-cultural barriers Studies across several countries[7, 8] have found that the biggest barrier to shifting most consumers towards alternative protein diets is quite simply their liking of meat and the difficulty of giving it up. This can be an underlying taste preference but is also due to meat-eating occasions being strongly embedded in sociocultural behaviours (e.g. meal planning and the weekly shop) and in relevant situations (such as family meals and outings, traditional Sunday roasts, barbecues and festive celebrations). German celebrity strongman and vegan Patrik Baboumian. Photo by Caroline Pitzke & Christine Fiedler by courtesy of PETA Deutschland e.V. from Wikimedia Commons A comprehensive review8 of research into consumer barriers revealed health considerations, convenience factors, stereotyping and potential disruption to family life as the main obstacles. For example, there is concern amongst some consumers and professionals that a plant-based diet would lack certain nutrients. Some researchers argue that plant-based diets can run the risk of lower quality protein intake, other concerns have been raised about the risk of micronutrient deficiency in badly planned vegetarian diets. On the other hand, some researchers are expressing the view that an increasingly wide range of new alternative protein sources can address nutritional concerns. It is important, however, to consider that consumers can also have health concerns about meat substitutes, not only because of insufficient levels of micronutrients but also due to additives – leading to a perception of artificialness7. In countries with strong meat-eating cultures, such as Australia and the United States, plant-based diets may have negative associations for many consumers. These can include stereotyping of vegetarians and vegans as being malnourished with protein, vitamin and mineral deficiencies. In some instances, social stigmas can be linked to perceptions of vegetarians being weak in body and mind. Attempts to address health perceptions of plant-based diets are often made through the media. For example, Germany's strongman Patrik Baboumian starred in the 2018 documentary The Game Changers to help dispel the myth that vegans are weak. It should be emphasised, however, that scientific views on the impact of plant-based nutrition on overall mental health are in fact divided8. The perceived and real barriers for consumers moving to a vegan diet are wide-ranging9. The initial hurdle to an individual considering a new diet is likely disruption to the rest of the household, with different meals required to be shopped for and prepared. Additional reasons for consumers rejecting a vegan diet are: lack of interest and willingness, expected inferior taste, predicted higher price and overall convenience factors, such as anticipated complications of preparation, lack of appropriate cooking skills and difficulty in obtaining information about types of food suitable for replacing meat. In addition, consumers often face a lack of vegan options on restaurant menus when they eat out or buy take-aways. A consumer study in the US10 on overcoming barriers to plant-based diets investigated interventions over a three-week trial, including access to a webpage with information about plant-based diets, preparation guidance, recipes and recommended shopping lists. In addition, one group was given grocery vouchers whilst the other received dine-in vouchers for local vegan restaurants. At the end of the trial, consumers across both groups had increased positive perceptions towards plant-based foods and, as an extra benefit, individuals had all made a significant weight loss of approximately 1.5 to 2kg. Building on the impact of the accessibility of alternative protein products at the point-of-sale, a recent controlled trial in a major supermarket chain across the UK11 found that a prominent positioning of meat-free products in the meat aisle led to a 31% increase in sales of meat-free alternatives (i.e. mince, meatballs, burgers and sausages). Interestingly, over the study period of 3 months this intervention was not effective in reducing sales of meat products. Further research is required to explore the longer-term impact of meat analogues on meat product sales and the likely effect of ingredient lists (i.e. clean labels) on the sales of meat substitutes. One of the most challenging sensory qualities to simulate is the ‘real meat’ texture. Sensory properties and challenges for product developers Several reports have shown that our genes are responsible for our food preferences and have categorised us as non-tasters, medium-tasters and supertasters. Supertasters have a higher sensitivity to certain tastes and have been described as disliking bitter, sweet and fatty products as well as most vegetables containing bitter compounds. This genetic explanation as to why some people dislike certain vegetables is a possible barrier to eating sustainably. In fact, studies have demonstrated that vegetarians tend to be non-tasters and that supertasters are less likely to adhere to plant-based diets[12, 13]. A way to address the sensitivity of supertasters to bitterness is to mask the taste or block it from reaching the receptors, an approach that may impact overall sensory characteristics and can be technically challenging to achieve. In addition, experience and commitment to eating healthier foods may overcome the genetic basis for disliking vegetables or plant-based diets. Would you or wouldn't you eat snackable insects? A reaction of disgust from a supertaster Courtesy Nicola Stanley Access to recipes and information about plant-based ingredients and dishes can help change consumption behaviours Supertasters are more likely to experience the feeling of disgust14 when eating foods that they dislike, thus the idea of eating products made of moulds (i.e., mycoproteins) or insects will likely receive a more negative response. Moreover, it was suggested in previous studies15 that supertasters are more likely to suffer from food neophobia (fear of trying new foods) and thus will be less adventurous in consuming novel foods that may be considered sustainable. One of the main barriers to consumers enjoying sustainable foods is the inferior sensory quality compared to animal-based products[16, 17]. This is due to differences in the macro composition, i.e. proteins, lipids and carbohydrates18, that influence the sensory properties of food products such as meat and dairy, beverages, bakery products, noodles and pasta. The sensory properties of meat analogues in various categories, such as plant-based (e.g. cereals and legumes), cell-based (i.e. in vitro or cultured meat), fermentation-based (i.e. mycoproteins) and others, such as microalgae and insects, have been widely explored19. One of the most challenging sensory qualities to simulate is the ‘real meat’ texture. This is attributed to the characteristics of whole muscle tissue consisting of muscle fibres, connective tissue and adipose tissues, which are organised into complex ordered structures[17, 18]. Appearance including colour, as well as aroma and flavour are also quite difficult to mimic. Meat analogues should be pinkish-red with a wet smooth and shiny surface prior to cooking and brown with a rough dry and dull surface after cooking. Although cell-cultured meat and mycoproteins have been synthesised to form elongated fibres to imitate animal tissues, these alternative proteins are still under development. The most widely explored raw materials for meat analogues are those from plants, such as legumes, sometimes referred to as ‘poor man's meat’. Legume proteins are made up mostly of globulins (i.e. globular proteins), which dictate their technological functionality. The structural design of these globulins makes it difficult to mimic the sensory properties of animal-based foods. Moreover, legume-based products often suffer from unacceptable aroma and flavours, such as ‘beany’ or ‘nutty’ notes, that may be due to the natural aromatics present in the raw material or oxidation of the unsaturated fatty acids or the liberation of lipoxygenases. McClements and Grossmann18 discussed two approaches, physicochemical and processing, that may be used either individually or in combination to enable plant-sourced materials to simulate the texture of animal meat. Physicochemical solutions aim to control the molecular interactions and configuration of plant-derived biopolymers to design meat-like structures. These biopolymers involve plant proteins and polysaccharides, which are optimised by selecting the most appropriate raw materials, concentration and solution properties (including pH, mineral composition and temperature). Processing approaches use high-shear or extrusion mechanical devices to form meat-like structures and textures. An Impossible Burger with fries and ketchup at Gott's Roadside in Napa, California Photo By Sarah Stierch on Flickr To mimic meat-like aroma and flavour, for example, Impossible Foods has patented soy leghemoglobin, which is used to manufacture its meat analogue products. When exposed to heat during cooking, leghemoglobin's heme undergoes oxidation to produce aromatic compounds akin to those in cooked real meat. Not only mimicking the odour and flavour of meat, this same component also gives Impossible Foods’ products their pinkish-red colour. Further encouraging news about soy leghemoglobin is that from a nutritional perspective it has also been found to have similar iron bioavailability to bovine hemoglobin20. Future direction Scientists, governments and the food industry are all helping to shift consumers towards eating healthier and more sustainable diets. This is possible through gaining a detailed understanding of the barriers to consumption and working to overcome the many hurdles involved. It is not simply about matching the sensory experience of meat using substitutes, although getting this right is one of the major technical challenges. Communication is an important tool for nudging consumers towards making more sustainable choices, whether via traditional or social media channels, or through product labelling and linking this to smartphone apps for more information. Studies are also starting to focus on the importance of visibility and availability of meat alternatives at the point-of-sale, making them more accessible within stores and at restaurants. Market success will come from designing products that are versatile as meal components, easy to prepare, forgiving of consumer cooking skills, provide positive health benefits, are not seen as artificial and are perceived as being value for money. The future emphasis for the food industry will be on developing alternative, tasty protein products that fit with consumer lifestyles and traditions. To ensure consumers buy, try and continue to purchase alternative protein products, further developments are needed. Market success will come from designing products that are versatile as meal components, easy to prepare, forgiving of consumer cooking skills, provide positive health benefits, are not seen as artificial and are perceived as being value for money. A tall order perhaps, but, as we have seen, not entirely impossible. Dr Nicola Stanley, Director, Silver Dialogue and communications lead for the IFST Sensory Science Group (SSG) with Prof Casiana Blanca Villarino, University of the Philippines and Prof Isabella Nyambayo, Coventry University. email nicola@silverdialogue.co.uk The idea for this article arose from a discussion within the SSG of which the authors are active participants. 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