VEGANALYZEQuinoa - Pseudocereal with High-Quality Proteins and Antioxidants
Quinoa seeds are the seeds of the quinoa plant (Chenopodium quinoa Willd.), which belongs to the family of goosefoot plants (Chenopodiaceae). The plant, whose tender leaves can also be eaten, can be cultivated up to a height of 3,800 meters above sea level and can grow up to 3 meters tall under optimal growth conditions 1 2 3. It is believed that the cultivation of quinoa began 7,000 years ago in the Andes 4. Mixtures of quinoa and fat, known as "war balls," were used during that time to sustain the Inca armies as they marched across the Andes 5. Nowadays, the nutritious seeds are cultivated in 95 countries 6. However, the main cultivation area still lies in the South American Andes (Bolivia, Ecuador, and Peru), where the growing conditions are optimal. The annual quinoa production amounts to approximately 80,000 tons 7.
Biologically, quinoa is related to spinach, chard, and beetroot 8. There is no relationship with true grains. Therefore, quinoa belongs to the group of pseudocereals.
The year 2013 was declared the Year of Quinoa. Its popularity has increased enormously in recent years, probably mainly due to its numerous health-promoting properties. Due to the variety of positive benefits on health caused by its components, quinoa is also considered a functional food and "superfood." The benefits are achieved through the minerals, vitamins, fatty acids, and antioxidants, which primarily protect cell membranes and support neural functions 9.
The seeds are small, round, and flat. Quinoa is usually found in the grain products section in stores. The color range of the 1 to 2.6 mm seeds includes white, yellow, red, purple, brown, and black 10.
Quinoa as a high-quality amino acid source
All nine essential amino acids are present in sufficient quantities in quinoa. According to studies, quinoa is a high-quality plant protein source 11. The amino acid composition, especially that of the essential ones, is almost ideal 12 13. The protein content of uncooked quinoa is approximately 14 g per 100 g, and cooked quinoa has about 4 g per 100 g. This makes quinoa one of the best plant-based protein sources. Additionally, quinoa has more protein than barley, oats, rice, and corn, and roughly the same amount as wheat 14.
In many plant-based foods, the proportion of the essential amino acid lysine is lower 15. However, in quinoa, it is present in very high amounts at 0.77 g per 100 g. It is needed for muscle building and recovery, among other things.
In addition, the amino acids leucine (0.84 g), methionine (0.31 g), and tryptophan (0.17 g) are also present in relatively high proportions in quinoa. Leucine is involved in muscle protein synthesis, which builds and repairs muscle tissue. Methionine is needed, among other things, for the body's production of taurine, which is involved in the functioning of the nervous system and eyes. Tryptophan is involved, among other things, in the formation of proteins in the muscles and is required for the production of the happiness hormone serotonin.
Quinoa also contains the amino acid derivative betaine in high amounts, with 3,900 μg per gram 16. Betaine is involved in the regulation and reduction of homocysteine levels in the body. Elevated homocysteine levels are associated with increased overall and cardiovascular mortality, increased occurrence of stroke, dementia, Alzheimer's disease, bone fractures, and higher prevalence of heart diseases 17. Additionally, betaine may play a role in athletic performance 18.
Quinoa as a Source of Vitamins
Vitamins of the B group are required for numerous metabolic processes. Vitamin B2, in particular, which is needed for energy and cellular metabolism, is found in higher concentrations (0.32 mg per 100 g) in quinoa.
Vitamin E (tocopherols and tocotrienols) is also abundantly present with 7.42 mg 19 20. It acts as an antioxidant and is required for fat solubility. Additionally, quinoa contains the carotenoids lutein and zeaxanthin, which play an important role in protection against age-related macular degeneration 21 22.
Losing Weight with Quinoa
Quinoa is rich in healthy fiber with 7g per 100g. 78% of it consists of insoluble fiber, while 22% is soluble fiber. 23. Fiber primarily promotes a healthy digestive tract (intact gut flora). Study results show that quinoa can promote or maintain the health of the gut flora through its prebiotic potential 24. Furthermore, fiber is generally associated with a lower risk of obesity 25. Additionally, fiber promotes a feeling of satiety without providing calories, thus aiding in weight loss. Studies suggest that after consuming quinoa, the feeling of satiety is higher compared to wheat or rice 26.
A high-fiber diet is also associated with extended life, as it may reduce the risk of overall mortality 27.
Larger amounts of a steroid-like substance (ecdysterone) are also present in quinoa 28. However, studies have found that ecdysterone has no impact on lean body mass or anabolic and catabolic hormone status 29.
Healthy fatty acids
Quinoa contains high levels of healthy fats (6 g per 100 g). Over 50% of these are polyunsaturated fatty acids (PUFAs). The important Omega-3 fatty acids for vegans, which are part of PUFAs, are present at around 5% (0.26 g per 100 g). The Omega-6 to Omega-3 ratio is 6 to 1, which is favorable compared to other plants 30.
Quinoa is beneficial for the cardiovascular system
Subjects who consumed quinoa instead of gluten-free pasta and bread had lower triglyceride concentrations and lower production of free fatty acids 31. It is therefore believed that quinoa also promotes a healthy cardiovascular system since high triglyceride levels in the body are associated with cardiovascular disease 32.
Antioxidant and anti-inflammatory benefits
Free radicals that damage cells are neutralized by antioxidants. Natural antioxidants are abundantly present in quinoa seeds - red quinoa contains significantly more than yellow quinoa 33 34. By sprouting the seeds (at 22 degrees in fresh water; duration about 3 hours), the amount of antioxidants is even increased 35 36. The proportion of antioxidants, however, decreases slightly during the cooking and baking of quinoa 37 38.
Quinoa also contains compounds such as flavonoids (such as flavonoid glycosides), bioactive phytoecdysteroids, polyphenols, and phytosterols, all of which are considered secondary plant substances 39 40 41. Polyphenols and flavonoids are plant antioxidants that bring benefits to human health 42 43 44. They are present in quinoa in larger quantities than in grains, for example 45. Important representatives of flavonoids are quercetin and kaempferol (both also present in high quantities in quinoa) 46. They have anti-inflammatory properties and may potentially protect against cancer 47 48. Phytosterols such as β-sitosterol, campesterol, brassicasterol, and stigmasterol, which are present in quantities of up to 118 mg per 100 g in quinoa, are capable of reducing the "bad" LDL cholesterol level in the blood serum 49 50. With the daily consumption of a quinoa bar over a period of 30 days, the blood lipid levels of 22 participants aged 18 to 45 years improved. This resulted in a reduction in the number of triglycerides in the blood as well as a decrease in total cholesterol and LDL levels 51. Another study from 2014 also confirms the cholesterol-lowering effect of quinoa 52.
In addition, quinoa also contains polysaccharides, which are an excellent source of natural antioxidants. 53.
The colored varieties of quinoa from Peru also possess an antioxidant capacity due to free and bound phenolic compounds and betalains. 54.
Minerals for the immune system and muscle development
Quinoa contains many essential minerals such as iron, magnesium, manganese, zinc, potassium, phosphorus, and calcium. 55.
Iron is needed for blood formation and also for oxygen transport to the cells. Magnesium is involved in the transmission of nerve impulses, enabling muscle contractions. Manganese is an antioxidant that protects mitochondria from damage during energy production. Zinc is utilized by the immune system and is required by cells for cell division. Potassium is necessary for muscle building and protein synthesis. 56. Phosphorus and calcium are essential for healthy bones.
You can find information about additional nutrients and nutritional values of quinoa here.
Neutralizing saponins, phytic acid, and oxalic acid in quinoa
Quinoa not only contains healthy nutrients, but also bitter substances and toxic compounds such as saponins, which are mainly concentrated in the husk 57 58. Saponins protect the seeds from microbial infections and feeding by insects and birds 59. Most commercially available quinoa seeds have already had the bitter-tasting husk removed. However, traces of saponins can still be found on peeled seeds.
Saponins can reduce nutrient absorption and cause intestinal damage. 60. However, several studies have also shown that saponins possess anticarcinogenic, antiviral, antimycotic, hypocholesterolemic, hypoglycemic, antithrombotic, diuretic, and anti-inflammatory activities. 61 62.
To remove the saponins, simply place the seeds in a sieve and rinse them under warm running water, which will remove the soapy film 63. This will also enhance the slightly nutty flavor. A plant-based alternative with fewer saponins is canihua, which is closely related to quinoa and also belongs to the group of pseudocereals.
It is also important to note that quinoa contains phytic acid (1.18 g per 100 g) and oxalic acid (143 to 232 mg per 100 g), which reduce or completely block the absorption of minerals such as calcium and iron 64 65 66. Soaking, cooking, fermenting, or sprouting the seeds prior to consumption helps remove or reduce these compounds, thereby increasing the bioavailability of minerals for the body 67 68. This can increase the solubility of iron, for example, two to four times by soaking and sprouting 69. The absorption of iron from quinoa can be significantly improved by consuming foods high in vitamin C simultaneously 70.
Quinoa is gluten-free, but...
Quinoa is touted as a gluten-free food. In vitro study results from 2012 involving 15 quinoa varieties showed that two of them (Ayacuchana and Pasankalla) contain celiac-toxic epitopes that can trigger immune reactions in some patients with celiac disease 71. However, the levels were below the maximum thresholds for gluten-free foods, according to studies. Further research conducted in 2014 on this topic indicated that consuming 50g of quinoa daily for a period of 6 weeks can be considered safe for celiac patients 72.
Cooking Quinoa
The South American pseudo-grain can be used raw or cooked, making it versatile for kitchen preparation 73. It also serves as a good alternative to rice and pasta. The consistency after cooking (2 parts water, 1 part quinoa, cook for approximately 15 minutes) is similar to that of rice.
Infinite Recipe Possibilities with Quinoa
Quinoa goes very well with muesli and cold salads. The seeds can be ground into flour like other grains. The flour can be used as an ingredient for baking. Bread, muffins, cookies, and cakes can easily be prepared with quinoa. Quinoa can also be used as an ingredient for pancakes, vegan burgers, or smoothies. It is also possible to pop the seeds like popcorn. Additionally, quinoa can serve as a base for soups.
Due to its high content of D-xylose, maltose, and fructose, quinoa can also be used as a component of malt beverages. 74.
In addition, quinoa protein is a potential candidate for the production of quinoa protein isolate due to its optimal amino acid profile. 75.
Quinoa seeds can even be fermented into alcoholic beverages. In South America, the traditional drink "Chicha" is also made from quinoa. 76.
Furthermore, quinoa sprouts can be consumed. They have a taste similar to spinach.
Buying Quinoa
You can find quinoa in health food stores, organic shops, some drugstores, an increasing number of supermarkets, and order it online.