The citrusy grass – lemongrass

A tufted, aromatic, evergreen clump-forming and perennial grass with a sweet taste and citrusy flavour known as lemongrass are not only used in Asian recipes. It has other common names such as West Indian lemongrass, Seregrass, fever grass, Ce Kala, Nche awuta, Ahihia tii, Hhashel laymum, and Koriko oyibo. It is a herb that originated in Asia and Australia that travels along the spice route from Asia to Europe. It is also known as citronella grass under the family of Gramineae, which comprises approximately five hundred genera and eight thousand herb species. It is native to warmer regions of Africa, Asia, and Australia. A feature of many species under this genus is the aromatic foliage in which it possesses essential oils in the tissues that is a lemon-like odour of the essential oil present in the shoot.

As a member of the grass family that is densely clump-forming, mostly with long and flattened leaves, lemongrass is a clustered spikelet sent up with long-stalked seed heads that are wholly or silky-haired in some species. The leaves are long, green, glaucous, linear, tapering upwards and along the margins. The leaf-sheath is tubular and acts as a pseudostem. It has an economic lifespan of about five years. Therefore, this plant produces flowers at matured stages of growth. The inflorescence is a long spike about one meter in length. The rhizome of the lemongrass produces new suckers that extend vertically as tillers to form dense clumps.

This genus has several species of economic importance for their aromatic oils that have been widely commercial in aromatherapy and skincare products. Lemongrass oil of commerce is popularly known as Cochin oil.  Some species of this genus are potentially ornamental in warm climate plantings. The growth of the lemongrass strongly depends on several climatologically factors like temperature, rainfall, humidity, and the level of soil fertility. Their main horticultural requirement is a climate with a long summer growing season. They need well-drained, fertile, and light-textured soil. Some species, including lemongrass, may not overwinter successfully if winters are cool and wet. They should be replanted each year in the late spring in such climates, which sunny days are preferable. This is because cloudy and misty conditions tend to depress the leaf oil content. Harvesting can begin once the night dews have evaporated from the plants after two months of planting. The composition of plant oils and extracts varies according to the local climatic and environmental conditions.

Lemongrass is scientifically known as Cymbopogon citratus, which is a valuable grass. This specific plant is believed that it is originated in India. It is characterized by a dense clump of long, gray-green leaves that may reach as much as six feet high, but it is commonly smaller. Even though it is a flowering monocot, it is rarely known to flower in cultivation. Therefore, it much less produces seed. The division of clumps can propagate lemongrass. Due to its excellent aromatic compounds, the plants need to be crushed, and bruised leaves have a strong lemon fragrance. However, the stalk and leaves are very tough and inedible. Apart from cultivating essential oil and culinary flavours, it can be used in other food categories like an alcoholic, non-alcoholic beverages, frozen dairy desserts, candy baked foods, gelatins, puddings, meat, meat products, fat, and oils. Furthermore, it is widely used to improve the flavour of some fish and wines and sauces flavoring.

Additionally, lemongrass can be used as a material for making lemongrass paper. The lemongrass oil is a traditional source of citral, which has a delicious smell of natural citral, which can be used in citrus perfumes in downstream products like soaps, perfumes, detergents, cosmetics, aftershaves, and candles that are used in aromatherapy. Citral is a mixture of two stereoisomeric monoterpene aldehydes.

Lemongrass looks similar to a spring onion but with a woodier and stalk. The whole fleshy white bases of the shoots from the plant are used in Southeast Asian cooking, which is collected and used fresh. The stalk is usually peeled off any dried-out layers, bash the woody top end with a rolling pin or the side of the knife to soften and help to release some of the aromatic oils. Then, the leaves can be used fresh or dried to make herbal tea. It can be used in stews, curries, stir-fries, and even cocktails. Moreover, the lemongrass can be steeped by mixing equal parts hot water and sugar to produce syrup. The syrup is often used to enhance the flavor of fruit salads or to make homemade soda with seltzer. A blend of lemongrass, garlic, ginger, and oil to stabilize the solution in the freezer during the winter. Such blend can be fried until fragrant and then cooked down with a can of coconut milk for a delicious sauce for noodles, vegetables, or seafood dishes.

Lemongrass is used for traditional purposes, an excellent folk remedy for coughs, elephantiasis, flu, gingivitis, headache, leprosy, malaria, ophthalmic, pneumonia, and vascular disorders. This plant can serve as a medicinal plant with a competitive market in pharmaceuticals, food, skincare and cosmetics, and perfumery markets. Several studies have shown that lemongrass is a good cleanser that helps to detoxify the liver, pancreas, kidneys, bladder, and digestive tract. It cuts down uric acid, cholesterol, excess fats, as well as other toxins in the body while stimulating digestion, blood circulation and blood pressure reduction, and lactation. Indigestion and gastroenteritis also will be alleviated. It also can be used in traditional skincare treatment like acne and pimples reduction, which acts as a muscle and tissue toner.

It is a crucial ingredient and fragrant herb that can be used in many more ways than in Asian cuisine, especially Thai fare. As a culinary ingredient, lemongrass can be used in a variety of ways. Besides Thai green curry, it can be added to masala chai to give it a citrusy twist. It is known to aid digestion. After a heavy meal, a quick cup of lemongrass tea is either by dipping a teabag or chopping the stalk and putting it in a few quarts of boiling water. A readymade dried lemongrass leaf. Dried lemongrass leaves are widely used as a lemon flavour ingredient in herbal teas. It can be done through the infusion of two to three leaves. Lemongrass tea is an ordinary tea that has a diuretic property that has no biochemical changes. It can be combined with green or black teas.

Lemongrass is rich in vitamins A, C, and other aroma chemicals, which are the nutrients that can improve the skin and hair. It has antioxidants, which the lemongrass is ranked as the highest antioxidant containing herbal tea consumed worldwide. Lemongrass has several critical bioactive compounds with antibacterial, antiobesity, antiseptic, antifever, carminative, antinociceptive, anxiolytic, and antihypertensive properties. Additionally, citronella essential oils obtained from the plants are found to be used as a mosquito repellent. It is categorized as one of the botanical repellents. Despite the great potential of essential oils, their use in food preservation remains limited mainly due to their intense aroma and toxicity problems.

Further readings:

Balakrishnan, B., Paramasivam, S., & Arulkumar, A. (2014). Evaluation of the lemongrass plant (Cymbopogon citratus) extracted in different solvents for antioxidant and antibacterial activity against human pathogens. Asian Pacific Journal of Tropical Disease4, S134-S139.

Manvitha, K., & Bidya, B. (2014). Review on pharmacological activity of Cymbopogon citratus. Int J Herb Med6, 7.

Wifek, M., Saeed, A., Rehman, R., Shehzad, M. R., & Nisar, S. (2016). Lemongrass: a review on its botany, properties, applications and active components. Int. J. Chem. Biochem. Sci9, 79-84.

Haque, A. N. M. A., Remadevi, R., & Naebe, M. (2018). Lemongrass (Cymbopogon): a review on its structure, properties, applications and recent developments. Cellulose25(10), 5455-5477.

Majewska, E., Kozlowska, M., Gruszczynska-Sekowska, E., Kowalska, D., & Tarnowska, K. (2019). Lemongrass (Cymbopogon citratus) essential oil: extraction, composition, bioactivity and uses for food preservation-a review. Polish Journal of Food and Nutrition Sciences69(4).