Protein plays a role in everything from muscle growth to supporting your immune system. But if you don’t eat meat, where can you find alternative sources of this essential nutrient? Dietitian Vanessa Furlong investigates.
Ask most people the best sources of protein and they’ll say red meat or fish. These are obviously off the menu for vegetarians and vegans, but fortunately plant proteins offer a nutritious alternative.
Protein has numerous functions in the body, but most significantly it plays a vital role in muscle growth and tissue repair. So it’s essential for good health.
How does plant protein differ from animal protein?
You can meet your protein needs through plant sources, but meat is undoubtedly the richest source of protein. For example, 100g chicken breast provides 22g protein, while 100g plain tofu provides 9–12g protein. The digestibility of meat protein is also higher (90–99 per cent) than plant protein (70–90 per cent), due to the plant cell walls being more resistant to digestion.
Both sources of protein contain significant amounts of essential nutrients. Red meat is rich in iron, zinc and vitamin B12 – three nutrients that non-meat eaters are at risk of being deficient in – while plant protein is rich in fibre and antioxidants.
Animal protein is a complete protein, meaning it provides all nine essential amino acids, while some plant proteins may lack one or more essential amino acids.
Plant proteins are typically derived from soybeans, pulses and more recently, fungus (Quorn products use fungus-derived protein). Soy protein and Quorn products are both complete proteins, whereas pulses are incomplete sources of protein.
It’s important to note, however, that it’s possible to obtain all the essential amino acids by combining a variety of plant proteins (like legumes and wholegrains). Keep in mind that you don’t have to combine plant protein-containing foods within the same meal. These foods only need to be combined over the course of a day, or even a week, so be sure to eat a wide variety of legumes, wholegrains, dairy and soy products.
Adults require a daily minimum of 45g protein for women and 60g for men.
Tofu, Textured Vegetable Protein (TVP) and tempeh are all made from soybeans. Soybeans provide fibre, iron, and omega-3 fatty acids. Although they technically meet the definition of a legume (plants with a pod), they are not always characterised as a legume because of their higher fat content.
Soybeans (36g protein per 100g fresh/ 9g per 100g canned)
Soybeans can be eaten as fresh beans/sprouts, canned, dried or edamame (in the pod). Soybeans are great for adding to soups and salads.
Tofu (9–12g protein per 100g)
Tofu, also referred to as bean curd, is made with curdled soy milk. Tofu is low in both fat and energy and contains a variety of vitamins and minerals, it is not rich in any one in particular.
Tofu is widely available in supermarkets and comes in both firm and silken varieties. Firm tofu is best suited to stir-fries, while silken or soft tofu is best for creating sauces and dips. Tofu is flavourless on its own, but readily absorbs added flavours. Flavoured tofu is also often widely available in supermarkets.
Textured vegetable protein (TVP) (50g protein per 100g)
TVP is a dried, shelf-stable soy product made from defatted soy flour. When reconstituted, TVP resembles mince in both look and texture. It is a fat-free, versatile ingredient that can be used in soups, stews and as a substitute for mince. TVP is sold in other forms including flakes, nuggets, grains and strips. Like tofu, TVP is flavourless on its own.
Tempeh (15g protein per 100g)
Tempeh is made from fermented soybeans. It is a source of iron and contains healthy polyunsaturated fats. Tempeh is higher in sodium than tofu or TVP because it’s prepared in a brine solution. Tempeh, which is often pan-fried, is widely available in both plain and flavoured varieties. It is firm to the touch and has a pleasant, nutty flavour.
Pulses are the edible seeds of legumes, and include lentils, beans and chickpeas (but not green beans or peas). Pulses are not complete proteins, so need to be eaten with other plant-protein sources. Combining legumes with nuts and seeds or wholegrains provides a complete source of protein.
Chickpeas (21g protein per 100g fresh/6.3g per 100g canned)
Chickpeas (also known as garbanzo beans) are low in energy, high in fibre and can be used in a range of dishes including soups and dips.
Haricot/navy beans (22.5g protein per 100g fresh/8.6g per 100g canned)
Also referred to as the ‘common bean’, the haricot bean is best known as the bean used in commercially prepared baked beans. In addition to being a good source of fibre, the haricot bean is rich in both folate and potassium.
Lentils (24g protein per 100g fresh/4.8g per 100g canned)
Split red lentils are the most common variety of lentil, though they are available in a number of other colours including brown, black and green. Lentils are high in both fibre and potassium and, because they are flat and thin, cook much more quickly than other pulses. Lentils can be used in soups or to make dahl, a traditional savoury Indian dish.
Mince (15.9g protein per 100g)
Quorn is a plant-based meat substitute that is derived from the fungi family. Quorn is low in fat and is a complete protein. Like TVP, Quorn’s look and texture resembles mince and it is flavourless. Pre-prepared Quorn products such as sausages, cottage pie and mince are available in the frozen food aisle of supermarkets. However, be aware that Quorn contains a small amount of egg white, so is not suitable for vegans.