Rasa (रसः)

“Rasa” (Samskrit : रसः) is one among the five qualities of dravya (द्रव्यम् substance). The term “rasa” means taste or the perception of taste. Also the guna (गुणाः quality) of the rasanendriya (रसनेन्द्रियम्) is known as rasa (the rasa dhatu among the saptdhatus is distinct from this rasa) Rasas in dravya (substance) are known by their effects in our body.

व्युत्पत्तिः॥ Etymology

रस्यत आस्वाद्यत इति रसः | (Char. Samh. 1.64) rasyata āsvādyata iti rasaḥ | (Char. Samh. 1.64)

Meaning: Rasa means which can be perceived by the tongue or that which can be tasted.

रसभेदाः ॥ Types of Rasas

There are shadrasa meaning six in number:

रसाः स्वाद्वम्ललवणतिक्तोषणकषायकाः| षड् द्रव्यमाश्रितास्ते च यथापूर्वंबलावहाः (Asht. Hrud. 1.14-15) rasāḥ svādvamlalavaṇatiktoṣaṇakaṣāyakāḥ| ṣaḍ dravyamāśritāste ca yathāpūrvaṁbalāvahāḥ (Asht. Hrud. 1.14-15)

Meaning: Madhura, Amla, Lavana, Katu, Tikta and Kashaya are 6 types of rasa which are present in substances. These rasas are in decreasing order of providing strength to the body.

Svadu/Madhura (स्वादु / मधुरः । sweet), Amla (अम्‍ल । sour), Lavana (लवणः । salty), Katu (कटुः । pungent), Tikta (तिक्तः । bitter) and Kashaya (कषायः । astringent) are the 6 types of rasa. According to Ayurveda acharyas these rasas provide strength to the body when consumed through diet and medicines. Although all these rasas provide strength, not all of these have equal ability to provide strength. Acharya Vagbhata states that, these rasas are in decreasing order of providing strength to the body. This means madhura rasa imparts maximum strength whereas Kashaya rasa lowest.

रसोत्पत्तिः तथा पाञ्चभौतिकत्वम् ॥ Origin of rasa and their panchabhautikatavam

Each of the 6 rasas constitutes of two mahabhutas (महाभूतानि). For every rasa those 2 mahabhutas which are dominantly found in it have been specifically mentioned by Ayurveda. The dominant mahabhutas for each rasa have been listed in the table below.

Rasa (रसः)	Dominant Mahabhutas (महाभूताधिक्यम्)
Madhura	Prithvi, jala(earth+water)
Amla	Prithvi, tejas(earth+fire)
Lavana	Jala, tejas(water+fire)
Katu	Vayu, tejas(air+fire)
Tikta	Vayu, akasha(air+ether)
Kashaya	Vayu, prithvi(air+earth)

For manifestation of any rasa, jala mahabhuta and Prthvi mahabhuta are essential.

रस-अनुमानम् ॥ How to determine rasa

Rasas are found in dravyas (द्रव्यम् । substances). Thus, rasa of a dravya can be determined by either tasting that dravya (i.e. on contact of dravya with tongue/ sensory organ). According to Darshana shastras (दर्शनानि) rasa can be determined by three modes as follows,

1. Pratyaksha (प्रत्यक्षम्। Direct perception by senses)- By directly tasting a dravya
2. Anumana (अनुमानम्। Inference drawn on the basis of well established relationships that are previously known to the individual)- On the basis of its effects on body after its contact and
3. Aptopadesha (आप्तोपदेशः। Knowledge obtained from trusted sources like classical treatises, Gurus etc)- As described in classical treatises/books

Here mainly pratyaksha pramana (प्रत्यक्ष प्रमाणम्) is used. When any dravya (द्रव्यम् । substance) comes in contact with rasanendriya (रसनेन्द्रियम् । Gustatory sense organ or taste buds in tongue) a peculiar taste is perceived this is called rasana pratyaksha jnanam (रसनाप्रत्यक्षज्ञानम् । Rasana- tongue, Pratyaksha-direct perception, Jnana-knowledge).

अनुरसः ॥ Concept of Anurasa

Anurasa (अनुरसः) or uparasa (उपरसः) are those which are not perceived at first (contact with body/organs) but are perceived at the end or not at all. Anurasas are perceived by anumana pramana (अनुमानप्रमाणम् । inference) but can only be understood by aptopdesha (आप्तोपदेशः । ancient literature or classical treatises). For example, Ayurveda treatises have in depth description of various metals and minerals for medicinal use. In Ayurveda, the action of each of the medicinal drug is determined based on its rasa, veerya, vipaka, karma and prabhava. However, it is not possible to taste any raw metal/mineral to understand its rasa. In such cases, description of these medicinal substances available in classical treatises helps one to understand their various properties like rasa, veerya etc. On this basis madhura rasa in Suvarna (सुवर्णम् । Gold), rajata (रजतम् । Silver) is not perceived but is known by reading classical literature which is authentic source of information on Ayurveda. This type of knowledge about rasa or anurasa is said to be through Aptopadesha pramana.

विविधाः रसाः तथा तेषां गुणाः ॥ Properties of rasa

Each of the six rasas possess peculiar properties. These properties are responsible for their specific action inside body. Therefore one can make therapeutic use of dravyas through their rasas only when one understands properties of each of these rasa as described in classical literature of Ayurveda. Effect of each rasa on various body components, consequences of excessive use of each rasa are described in brief here.

मधुर रसः ॥ Madhur rasa

It nourishes the saptdhatu, provides longevity, helps maintaining health of sensory organs, enhances bodily strength and lusture. Helps pacifying pitta and vata dosha. It also reduces burning sensation and excessive thirst. It is advantageous for skin, hair and throat. It promotes strength to those who are weak and emaciated. It has guna (properties) of being snigdha (unctuous), sheeta (cold) and guru (heavy). If consumed in excess amounts may lead to various abnormalities like obesity, laziness, excessive sleep, heaviness of the body etc.

अम्‍ल रसः ॥ Amla rasa

Amla rasa dravyas (अम्‍ल रस द्रव्याणि । sour tasting substances) are appetizing, improve agni (अग्निः । digestive fire), quickly energize body as well as mind and also strengthen them. Amla rasa helps in digestion of food by balancing the water content (helps moisten the food) required for the process of digestion. It provides nourishment and energy. Enhances sensory organs by quickly refreshing them. It helps to maintain normal flow of vata dosha in body. It is believed to be good for Hrudayam(हृदयम्) (due to its action on sensory organs and mind). It increases salivation. It has guna (properties) of being laghu (light), snigdha (unctuous) and ushna (heat).

If consumed in excess amounts amla rasa leads to teeth sensitivity, increases thirst, increases pitta dosha. Also it may cause weakeness in body, heart burn and burning sensation in throat.

लवण रसः ॥ Lavana rasa

Lavana rasa (dravya) aids digestion, improves appetite, helps to correct the sluggish digestion. It acts as expectorant and helps to clear pathways. Pacifies vata dosha, increases salivation, improves circulation by cleansing the channels, provides laxity to the body, liquefies kapha, goes well with food, not very guru (गुरुः । heavy) in nature, is snigdha (स्निग्धः । unctuous), ushna (उष्णः । hot). When consumed in excess lavana rasa aggravates pitta dosha, excessive thirst, causes skin diseases, damages teeth, causes inflammations, leads to hair fall, graying of hair.

कटु रसः ॥ Katu rasa

Katu rasa helps to keep the mouth clean, improves digestion and food absorption, cleanses nasal channel, causes lacrimation, enhances sensory organs, alleviates sluggish digestion, swellings, heaviness of body, improves appetite, relieves itching, heal wounds, kill worms, helps remove blood clots, cleanses bodily channels, pacifies kapha dosha, is laghu (लघुः । light), ushna (उष्णः । hot) and ruksha (रुक्षः । dry) in guna (गुणः । property). If consumed in excess can cause malaise, weakness, loss of weight,burning sensation in throat,loss of strength, excess thirst, Giddiness, burning sensation in body, tremors and various vata disorders.

तिक्त रसः ॥ Tikta rasa

Tikta rasa dravya even though are distasteful help increasing the appetite, reduces giddiness, burning sensation, itching, various skin infections, thirst. It reduces fever, improves digestion, helps reduce excess moisture, fat, lymphatic fluid, sweat, pus, pitta dosha and kapha dosha. Reduces frequent urination and feces. Tikta rasa is ruksha (dry), sheeta (cold), laghu (light) in guna (property). If there is excess utilization it will cause weakness, fatigue, mental confusion, giddiness, dryness in mouth and various vata dosha related disorders.

कषाय रसः ॥ Kashaya rasa

Kashaya rasa is constipating and binding in nature. It helps in healing the damaged part, pacifies kapha, pitta dosha and rakta dhatu. It is ruksha (dry), sheeta (cold), heavy in guna (property). If there is over utilization of this rasa, it may lead to dryness in mouth, abdominal distention, speech disturbances, darkening of complexion, indigestion, weakness. It can also cause various vata dosha disorders when in excess.