The Environmental, Nutritional, and Health Benefits of Pulse-Enhanced Foods

Pulses, our environmental heroes. The environmental, nutritional, and health benefits of pulse-enhanced foods.

Pulses are mature, dried seeds that grow within pods of the legume (Fabaceae) family of plants used for human and animal nutrition (1). The world's leading producers of pulses are Australia, Brazil, China, India, Myanmar, and Canada (2). Worldwide, pulses are a staple nourishment for both humans and animals. They are widely consumed (3) as canned beans, chickpeas, and lentils in Europe and the US, and (4) as cowpeas, one of the most significant legumes in sub-Saharan Africa. Pulses, being rich in protein, carbs, dietary fibre, vitamins, and minerals, are essential components of well-balanced, nutrient-rich meals (5). Livestock is also fed with both the seeds and the leaves (6). Nutritious pulses constitute a significant share of a regular diet and are an affordable alternative to animal protein for smallholder farmers in poor countries.

Pulses - an alternative to cereals?

The nutritional, sensory, technical, and functional properties of legumes include their viscosity, ability to absorb water and oil, ability to produce foam, and ability to emulsify. Due to their ability to support the inclusion of legumes as ingredients in a wide variety of food alternatives, their functional qualities have also attracted attention. This can occur through the legume itself or its byproducts, including flours, brans, sprouts, aquafaba (a type of egg substitute typically prepared from chickpea water), extracts, and textured proteins (Picture 1).

Particularly, pulse flours may enhance the versatility and drive consumption of pulses (7). The use of processed pulse components in innovative, high-value food products is an expanding area of the food industry (8). Between 2024 and 2032, the global pulse flour market is projected to grow at a significant rate. The market grew steadily in 2022, and it is anticipated to rise over the estimated horizon due to the increasing adoption of strategies by major players. The size of the world market for pulse flour was estimated at USD 10000.0 million in 2021 and is projected to grow at a compound annual growth rate (CAGR) of 11.26% from 2024 to 2027, to reach USD 18970.0 million by 2027 (9).

Image 1. Fresh egg kinds of pasta made from (A) whole egg and common bread wheat flour type 00 or (B) dehulled malted GPB-Gradoli Purgatory beans flour, (C) SDC - Solco Dritto chickpeas flour, or (D) OL – Onano lentils flour (10).

Due to their ability to improve nutritional content (11–12), their multiple techno-functional qualities (13–15) and their capacity to create gluten-free food products (16–18), pulse flours are significant in the food processing industry. Relatively recently, there has been research on pulse flour milling, which involves the use of several pulse varieties to make flour and other staple food ingredients for use in processed foods. Thus far, studies on pulse flour have mostly shown its promise as a techno-functional food ingredient with added benefits including higher nutritional value and better health.

Studies on legume consumption, cereal-based diets supplemented with legume flours, and the extraction, functional characteristics, and impacts of polyphenols on the structural features of protein obtained from legumes have already been covered in a few studies. Recently, studies on the physicochemical and functional characteristics of legume components as well as their usefulness in the creation of food products have been published (19–22). 

Legumes contain chemicals that might negatively impact their nutritional content and impair the protein's digestion when consumed, even if they have advantages in terms of nutrition, flavour, and diversity when cooking. According to Hall et al.(23), antinutrients already recognised to be present in legumes include phytates, trypsin inhibitors, lectins, and polyphenols, in addition to flatulence causes such oligosaccharides. Thermal processing can limit these antinutrients and diminish them by throwing away hydration water (24). Shi et al. (25) showed that soaking and cooking significantly decreased the levels of lectins, phytates, and oxalates—all of which are found in legumes. 

Soil-enriching pulses could transform the future of sustainable agriculture 

Pulses are environmental heroes because they "fix" nitrogen from the air by collaborating with rhizobia, a type of soil microbe, replenishing the soil with nutrients that promote soil growth. Legumes evolved the capacity to naturally contain helpful bacteria inside specific structures known as root nodules about 100 million years ago (26). Here, gaseous nitrogen from the soil and air is transformed by bacteria into a form that plants can use as nutrition. Legumes therefore require less nitrogen fertiliser than other vegetable and cereal crops. High-performing legumes can fix up to 300 kg of nitrogen per hectare (27), saving farmers around $1 per kg in fertiliser needed to meet the plant's nutrient requirements. 

Conclusion

It's important to emphasise legumes' minimal environmental impact in addition to their nutritional, technological, and sensory promise as new food options (28). From a technology perspective, adding legumes to cereal-based goods has been beneficial for both gluten-sensitive and coeliac individuals as a way to increase nutritional content and diversify meal options. 

References

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