Nawal Saeeda, Hafiz Muhammad Bilalb,*
aCollege of Food Science and Technology, Huazhong Agricultural University, Wuhan,
bCollege of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan,
*Corresponding author: [email protected]
Pseudocereals are well adapted for that environment where other crops find difficulty to grow. Pseudocereals are highly rich food because of their high protein content, minerals content, and healthy and balanced food quality. These foods are nutrients dense with the proper amount of all essential nutrients and have high bioavailability but sometimes they are designated as superfoods, at the same time ironically they are considered orphan crops because of their low consumption. Hence they fall under the category of neglected crops. Crops like Buckwheat, Quinoa, and Amaranth belong to pseudocereals. A limited research program is undertaking and focus these underused crops. But in recent years people become more health conscious and used these neglected crops so due to this malnutrition problem has seen a considerable declining trend.
Quinoa is derived from South America and named as Andean grain and has been the part of Andean cultural diet. Morphology shapes grass and grain like so it’s considered a pseudocereal. On the basis of geographic adaptation, it has 5 ecotypes. It is an important source of essential amino acids and gluten-free products. Since 2013, this crop gain much importance because many people become aware of this. The crop of quinoa is suitable for the marginal environment and its drought and salinity stress resistance. However, it`s sensitive to high temperature, and tolerance range from -8 to 35 Celsius. During flowering, the high temperature reduces their seed yield.
Quinoa has unique nutritional composition and a novel balance between oil, protein, and carbohydrate. Lysine an essential amino acid is high in quinoa but it is much less in other plant-based diets also, a good source of vitamins, essential fatty acids, and natural antioxidants. Thus, it has a high mineral composition such as Ca, Fe, K, and Mg than other cereals. However, it has several health benefits, especially for diabetic patients due to their low glycemic index. During germination, they release important bioactive phytochemicals phytoecdysteroids and 20-hydroxyecdysone. Due to its exceptional nutritional qualities, NASA included it in astronauts’ diets for long space missions.
Quinoa gained more importance due to its nutritional profile yet it has some disadvantage and contains some anti-nutritional factors like saponins which causes bitterness in the flour. This anti-nutritional component can be removed by washing or dehulling. Saponin is present in the seed coat and after washing the solution is used as bio-pesticides. By using conventional breeding techniques saponin content is controlled by recessive genes and genotypes. Extrusion and roasting techniques also reduce the saponin and bitter taste. Mineral inhibitor phytate is also high in quinoa various methods like cooking, washing, germination, and fermentation decreases phytate contents in quinoa. But much washing reduces vitamins and minerals contents. Phytate affects the bio-assimilation of important minerals such as iron and calcium.
Buckwheat is widely cultivated in Asia, Europe, North America, and South Africa. It is a versatile dicotyledon annual crop and is used as food, vegetable, and fodder. In China, Taiwan, and Japan it is recognized as a portion of potential functional food. Due to its chemical composition and conventional usage as cereal, also considered a pseudocereal. It has several species, out of nine species that have agricultural and nutritional importance, among them, only two are used for food purposes. Common buckwheat is also known as “sweet buckwheat.”
In recent years buckwheat production has increased because of its nutraceutical properties.
It is a nutrient-dense food and contains a high amount of proteins as compared to other cereals such as rice, wheat, millet, maize, etc. like quinoa it also contains a high percentage of lysine. Also, contain all essential amino acids and the amino acid content of buckwheat protein is 100 which is the highest among plant sources. Buckwheat protein also has cholesterol lowering effects.
Consumption of food containing buckwheat reduces cholesterol in blood serum and insulin indices. Buckwheat protein contains very low gluten and is good for people suffering from coeliac disease. Starch is a major carbohydrate in buckwheat grain that varies from 59 to 70% of dry mass and it depends on climatic and cultivation conditions. Due to its nutritional profile, it is used in India during fasting also, a rich source of fagopyrin, which is used to treat diabetes type 2. It is also rich in minerals such as P, Mg, K, Zu and Cu. In addition to the high quality of protein and minerals, also rich in bioactive compounds like flavonoids, phytosterols, and thiamin binding protein and these compounds have healing effects against chronic diseases.
Buckwheat is the only grain crop that contains rutin and has anti-oxidant and anti-inflammatory properties and is helpful in lowering hypertension in humans by reducing the fragility of blood vessels. So because of its unique nutritional profile and medicinal properties, it is a good alternative for food and nutritional security for marginal environments.
Despite having various health benefits the major issue is low digestibility of buckwheat proteins in humans due to antinutritional factors such as protease inhibitors and tannins. Washing, sprouting, germination, and fermentation lowers the content of antinutritional factor and increases the bio-availability of proteins.
Amaranth is an ancient crop and has been cultivated about 8000 years ago in South and Central America. It is a highly nutritive pseudocereal. About 1400 years ago it was used as a staple food in Mexico. Because of its nutraceutical value and climate resilience property, it has been relaunched and being promoted as a suitable crop for food nutritional security. Its leaves are being consumed as vegetables and seeds are used as cereals. It has been grouped on the basis of its usage as; grain amaranth and vegetable amaranth. It is fast growing cereal-like plant. Like another pseudocerea.
Lysine content is also higher in it. Amaranth protein is rich in sulfur-containing amino acids which are limited in pulses. Amaranth provides a balanced source of proteins because its amino acid content is close to the optimum protein reference pattern in human food recommended by FAO/WHO. In addition to the balance profile amaranth protein also has high digestibility. Apart from having a good amino acid composition, its protein is also gluten-free.
Besides the protein, it also has higher oil content than other cereals. The lipid of amaranth is also unique because contains high biological active compounds such as tocopherols, phytosterols, and squalene. Squalene is the obligatory precursor of sterols and unsaturated hydrocarbon and has antibacterial, anti-oxidative, and anti-tumor effects. Amaranth starch is mostly waxy due to the high percentage of amylopectin. So due to this, it has characteristics of high viscosity and high gelatinization. Its amylopectin granules are small in size so provide high water binding capacity, and high swelling power, and make amaranth a preferential source of starch in the food industry.
It is also a rich source of minerals like iron, calcium, sodium, magnesium and phosphorus. And also has good percentage of vitamin A, B and C. its vitamin capacity is an excellent source reducing vitamin deficiency. Recently its usage become popular as a functional food. It is complimentary dietary source of calcium. Hemoglobin content is increased by iron supplementation through amaranth. Administration of amaranth through oral dose increases the level of nitrate in plasma and as well as in saliva. By using amaranth flour with maize tortillas improve the bio availability of nutrients and reduce the effect of anthelmintic and diabetes.
Instead of having amazing nutritional profile it also contain some antinutritional factors like phytate saponins and tannins. These factors can be reduced by various chemical and mechanical ways include washing, dehulling, soaking, germinating, sprouting and fermentation.
So, the need of hour is to identify these crops and their varieties because they robust the resistance against the harsh condition of marginal environment and sustain food and nutritional security. These crops will help farmers in maintaining the productivity against a backdrop of rising temperatures, salinity, and increasing water scarcity and provide and sustainable way of adapting to climate change.