MINT OIL PROCESS AND FORMULA

Mints belong to the genus Mentha, in the family Labiatae (Lamiaceae) which includes other commonly grown essential oil-yielding plants such as basil, sage, rosemary, marjoram, lavender, pennyroyal and thyme. Within the genus Mentha there are several commercially grown species, varying in their major chemical content, aroma and end use. Their oils and derived aroma compounds are traded world-wide.

The four most commonly cultivated species are:

 Japanese Mint/Menthol Mint (M.arvensis)
 Peppermint (M.piperita)
 Spearmint (M. spicata)
 Bergamot mint (M. citrata)

All are herbaceous plants, readily sending out runners (rainy season) and stolons (winter), which develop new roots and shoots at the nodes and form plants. The entire aerial shoots together with foliage is a source of essential oil rich in menthol, carvone, linalool and linanyl acetate having use in pharmaceutical preparations and flavour industry.

For the past four decades, mints are commercially cultivated in India. Of these, the Japanese Mint, yielding menthol is grown extensively in northern India. Other major producing countries are China and Brazil and to a smaller extent Thailand and Vietnam.

The cultivation of Japanese or corn mint originated from Brazil and China. Subsequently, China and India overtook Brazil and more recently India has taken the leading position in cultivation of this essential oil yielding plant.

Japanese mint is a perennial ascending herb growing about 60-80 cm. in height and under favourable conditions may attain a height upto 100 cm. It is propagated mainly by its stolons. Leaves are lanceolate-oblong, sharply toothed; petiole is small about 5mm. in length. The leaf lamina varies from 5 to 15 cm. The leaf surfaces mainly lower side is covered with dense hairy growth of glandular trichomes. Flowers are borne in axillary and terminal verticillaster, abundant in number, purplish in colour. The flowers are small with corolla measuring 4-5mm., calyx 2-3mm., narrowly deltoid and acuminate. It does not produce seed and propagation is through vegetative means only.

At present, Japnese mint is cultivated in India on about 60,000 ha. of land with estimated production of 12,000 tonnes of mint oil which accounts for about 75% of total menthol mint production in the world.

The following Table gives estimated area & production of various mint species in India vis-à-vis world production.

Table: Estimated area and production of mint in India and abroad.

Japanese Mint (Mentha arvensis var piperascense) is an aromatic perennial herb, grown as an annual in sub-tropical parts of north India. The over-ground herb (foliage) on distillation yields an essential oil, containing high (75 – 80%) menthol content. The oil has a bitter cooling taste, harsh odour and is the principal source of menthol. It is used in combating cold, used as an ingredient in cough drops and related pharmaceuticals, dentifrices, cosmetics, mouth washes, scenting of tobacco products and flavouring of beverages. Synthetic menthol has also come in market but its volumes are meagre due to high cost of production. Besides, natural menthol is preferred in food and flavour industry.

The term “mint” is an umbrella term for the Mentha plant family that includes spearmint, peppermint, orange mint, apple mint, pineapple mint and more. Mint is a perennial and wide-spreading herb. When planted in good soil, mint grows wild, and can overtake gardens and lawns, making it a popular container gardening herb. The plant has a wide variety of uses, from a breath freshener to a stomach-soother. Each variety of mint has its own distinct flavor, but the two most well-known are spearmint and peppermint.

Spearmint’s relatively mild flavor comes from the chemical ingredient carvone. It’s most widespread use is Wrigley’s® Spearmint Gum. Peppermint’s flavor is similar to spearmint, but it contains the ingredient menthol, making its flavor stronger and more pronounced. Both spearmint and peppermint have menthol in them but peppermint contains higher menthol content (40% versus .05% in spearmint).

When on the extract aisle of the grocery store, there’s a difference as well. Mint extract is a mixture of spearmint and peppermint, whereas peppermint extract is just that.