The humble soybean is a master shapeshifter.
First eaten in Asia over 3000 years ago, it is a staple of many cultures. You’ve probably met it before… perhaps as a refreshing glass of soya milk or tofu thrown into a stir-fry for a protein kick, but dig deeper and you’ll discover a multitude of delicious and healthy soy based foods.
Here are three foods you probably never knew contained soy and why they’re a great way to improve your diet.
A vital ingredient in many dishes, from soup bases and glazes, to marinades and even hummus (an RYH recipe!), miso provides a rich, umami (savoury) flavour.
It is produced by fermenting a soybean and koji (fermented grain or legume) mixture. Here, the protein, carbohydrate and fat molecules stored within the beans are broken down to give intense flavour molecules. Variations in fermentation length and starter koji (type of grain) lead to different miso varieties. The Reset Your Health plan draws on white miso, fermented for shorter periods of time, to add a savoury kick to vegetable based dishes and the more intense red/brown rice miso, for a classic miso soup with soba noodles.
Miso is packed with copper, zinc, vitamin K and manganese (1). Unpasteurised varieties are a rich source of probiotic (2). In her book, the Reset Your Health founder defines a probiotic as a food that contains live bacteria that can survive the acid environment of the stomach and then increase the number of good bacteria in the gut. They are incredibly useful to our body, producing vital vitamins that our bodies need and chemicals that can kill diarrhoea viruses. Our gut bacteria, as we are seeing, can, amongst other things, reduce inflammation, the risk of diabetes and heart disease. In miso, the bacteria are essential for the fermentation process.
A few miso related points to consider:
- Only the unpasteurised varieties are probiotics (heating during pasteurisation kills any friendly bacteria).
- Remember, miso has a high salt content so ensure your consumption is within recommended daily allowances and take extra care on a low salt diet.
- Be aware that the preparation of miso varies. Miso can be slow fermented in barrels for months or years, but sometimes the manufacturers speed up the process and compensate for loss of flavour and colour with additives.
Green, sweet and fresh, edamame is the Japanese name for soybeans picked early, making them more succulent and crisp. Following a quick dip in boiling water, they make the perfect accompaniment and feature on the Reset Your Health plan, drizzled with olive oil and sprinkled with chilli flakes, as a satisfying snack with a spicy kick.
Perfect for a stir-fry or tossed into a salad, they also pack a nutritious punch. Not only do they have a high protein content compared to other plant food sources, but they contain all essential amino acids. As a result, they are comparable to animal sources of protein (3). They have a low glycaemic index (GI), meaning they do not raise blood sugar levels by significant amounts following consumption (compared to other legumes and carbohydrates) making them a suitable food source for diabetics (4). Consumption of foods with low GI is linked to slow glucose release (5), keeping you energised for longer.
Unlike miso, tempeh is a quick fermented soy product. Whole soybeans are mixed with microorganism cultures and shaped into ‘loaves’. During fermentation, which typically lasts for 24 hours, the beans are bound together and proteins and oils are broken down, producing flavour molecules. The product, often used as a meat substitute, is prepared in multiple ways; from frying and baking, to marinating and roasting, the cooking process develops a nutty flavour and meaty texture. In RYH, it adds savoury notes to a vegetable biryani.
How can tempeh improve your gut health? It has supposed prebiotic properties, meaning it helps the beneficial bacteria to thrive in the gut (6). A healthy gut microbiome is fundamental to maintaining human health and is the fundamental principle of RYH. In addition, due to the fermentation process, phytic acid, a typical soy anti-nutrient (substance that hinders the absorption of vitamins and minerals) is broken down, increasing the amount of nutrients the body can absorb from soy.
A quick note on the differences between tempeh and tofu:
- Both are highly nutritious and protein packed.
- Tempeh is fermented and significantly more robust, making it suitable for cooking .
- Tofu is prepared from soy milk much like cheese is prepared from dairy milk; a heating and salting process produces whey and curds, then curds are pressed. It is more delicate in texture and is a perfect addition to a soup or stir-fry.
How can eating soy improve wellbeing?
Our whistle stop tour of three diverse soy foods has shed light on the prebiotic properties of tempeh and probiotic properties of miso, two food types essential for maintaining tip-top gut health (pre- and probiotics). We’ve discovered how edamame make for snacking without the surge in blood glucose levels and provide and slow release energy, not forgetting their high vitamin and mineral content.
Why not treat yourself and your gut by including some of these in your diet- sign up to the Reset Your Health to access delicious recipes and inspiration on how to use them.
- Miso (Survey (FNDDS), 784305) [Internet]. FDC.NAL.USDA.GOV. 2020 [cited 26 Jun 2020]. Available from: https://fdc.nal.usda.gov/fdc-app.html#/food-details/784305/nutrients
- Frias J, Song YS, Martínez-Villaluenga C, González de Mejia E, Vidal-Valverde C. Immunoreactivity and amino acid content of fermented soybean products. Journal of Agricultural and Food Chemistry. 2008;56(1):99-105.
- Young VR. Soy protein in relation to human protein and amino acid nutrition. Journal of the American Dietetic Association. 1991;91(7):828-835.
- Your lifestyle, diabetes, and food [Internet]. DIABETES.ORG.UK. 2020 [cited 26 Jun 2020]. Available from: https://www.diabetes.org.uk/guide-to-diabetes/enjoy-food/eating-with-diabetes/your-lifestyle-diabetes-and-food-
- Glycemic index for 60+ foods [Internet]. HEALTH.HARVARD.EDU. 2020 [cited 26 Jun 2020]. Available from: https://www.health.harvard.edu/diseases-and-conditions/glycemic-index-and-glycemic-load-for-100-foods
- Kuligowski M, Jasińska-Kuligowska I, Nowak J. Evaluation of bean and soy tempeh influence on intestinal bacteria and estimation of antibacterial properties of bean tempeh. Polish Journal of Microbiology. 2013;62(2):189-194.