Ghṛta and Taila (Medicinal Lipids)
Table of Contents:
Ghrta and taila are prepared by boiling together one part of kalka (paste of herbs), four parts of clarified butter or oil and four parts of any decoction. The decoction is prepared by boiling one part of a coarse herb powder with four parts of water and reducing the volume by one-quarter. If the
FIGURE 3.8 A drug boiler used in the manufacture of kvatha. Photo courtesy: Nagarjuna Herbal Concentrates Ltd, Kerala (www.nagarjunaayurveda.com).
herbs are soft, four parts of water are taken. If the herbs are moderately hard, eight parts of water are taken, and, if very hard, 16 parts of water are taken. The volume is to be reduced by one-quarter (Murthy 2017e).
If the ghrta or taila is prepared using only water, decoction, meat juice or fresh juice of herbs, their volumes should be respectively, four, six and eight times of that of the kalka. If ghrta or taila is to be prepared with only water or decoction, the volume of fluid should be four times of the kalka or lipid material. If in the formulation, kalka consists of flow'ers, the flowers should be taken in one- eighth quantity of the lipid and water equivalent to four volumes of the lipid (Murthy 2017e).
The stage of filtering the product is determined on the basis of the texture of the sediment that forms when most of the water in the boiling mass is evaporated. When a significant volume of water is removed from the boiling mixture, it acquires a mud-like consistency. As evaporation progresses, sediments form. They are usually of three types - mrdu (soft wax-like), maddhyama (hard wax) and khara (very hard). Heating beyond the khara stage wall result in dagdha рака or a charred stage (Figure 3.12). Ghrta and taila filtered at this stage are unfit for use. Ghrta or taila filtered at mrdu рака are suitable for nasal instillation (nasya) and maddhyama рака is recommended for internal administration. Khara рака is suitable only for formulations that are used in body massage (abhyanga). Sarngadhara Samhita states that ghrta or taila should not be prepared in one day. They need to be prepared over several days, as a longer duration of preparation improves the quality of the medicine (Murthy 2017e).
Steam-jacketed stainless steel evaporators are employed for the large-scale manufacture of medicinal lipids (Figure 3.13). The lipids commonly used are sesame oil, coconut oil, castor oil and
FIGURE 3.9 Basket containing chopped and pulverized herbs. Photo courtesy: Nagarjuna Herbal Concentrates Ltd, Kerala (www.nagarjunaayurveda.com).
FIGURE 3.10 Forced circulator evaporator for concentrating kvatha. Photo courtesy: Nagarjuna Herbal Concentrates Ltd, Kerala (www.nagarjunaayurveda.com).
FIGURE 3.11 Packing of curna. Photo courtesy: Nagarjuna Herbal Concentrates Ltd, Kerala (www.nagar- junaayurveda.com).
Some Elements of the Master Formula tor Production of Triphala Curnam
clarified butter. The lipid, fine paste of fresh or powdered herbs, required volumes of water, decoction, juice of herbs, buttermilk, milk or meat juice are poured into the evaporators according to the formula. The evaporator is heated over mild heat. Decoctions or buttermilk are evaporated in five days and juice of fresh herbs (svarasa) in three days. Milk and meat juices are evaporated in two days and one day, respectively. The boiling mass is stirred frequently with large ladles, to improve
FIGURE 3.12 Mud-like stage (a), soft wax stage (b), hard wax stage (c) and burnt sediment stage (d). Photo courtesy: D. Suresh Kumar.
FIGURE 3.13 Steam-jacketed evaporators employed in production of medicinal lipids. Note froth on surface. Photo courtesy: Nagarjuna Herbal Concentrates Ltd, Kerala (www.nagarjunaayurveda.com).
Some Elements of ohe Master Formula for the Production of Amrta Ghrta
mixing of ingredients, encourage evaporation and to prevent sticking of solids to the bottom and sides of the evaporators (Anonymous 1978b). It is possible that during the long periods of continuous heating, cooling and stirring, many bioactive compounds in the herbs get incorporated into the lipid medium (see Chapter 11).
The ghrta or taila is filtered at the appropriate stage. Certain ingredients like camphor, rock- salt and saffron are powdered and put in the vessel into which the medicinal lipid is filtered. This process is called patrapaka (Anonymous 1978b). The finished product is packed in appropriate containers. The master formula of Amrta ghrta (Anonymous 1978b) is provided in Table 3.6 to serve as an example.
Ariṣṭa and Āsava (Fermented Liquids)
Arista and asava are liquids prepared by keeping drugs in water for a long time, allowing it to ferment. Arista are prepared by fermenting decoctions of herbs, whereas asava are prepared in cold water and fresh juices of herbs. If not specified, the quantity of water to be used in the preparation of arista is one drorta (12.288 kg). One tola (4.800 kg) of jaggery is used for sweetening the medium. 2.400 kg honey and 480 g of herb powder are also to be added (Murthy 2017f).
The process of preparing arista and asava through fermentation is called Sandhana kalpana, in which the mixture of powdered drugs, decoction, jaggery and honey is kept undisturbed for a specific period of time, usually 28 to 30 days. Fermentation generates alcohol, which facilitates the extraction of the active principles in powdered drugs. Moreover, the resultant product has good taste and flavor.
FIGURE 3.14 Modern brewing tanks in fermentation room. Photo courtesy: Nagarjuna Herbal Concentrates Ltd, Kerala (www.nagarjunaayurveda.com).
In earlier times when the process of preparing arista and asava was carried out in earthen pots, it was necessary to use a new pot each time a product was prepared. The vessel would be properly cleaned, and water was first boiled in the vessel. Absolute cleanliness was maintained, and the pot was fumigated using herbs like PippalTсйгпа (Piper longum) and the inside of the pot was then smeared with clarified butter before starting the fermentation process. When bulk manufacturing of ayurvedic products started to flourish, it became difficult to manage with earthen pots. New brewing vessels were introduced into the process. At present, brewing tanks with a storage capacity of even 10,000 liters are being used in the industrial manufacture of arista and asava (Figure 3.14). The smearing of clarified butter and fumigation with PippalT сйгпа are replaced with modern fumigation techniques.
In the traditional manufacture of arista, the crude drugs mentioned in the formula are coarsely powdered and then made into kvatha, which contains the water-soluble bioactive compounds. The kvatha is then filtered and poured into the fermentation tank. According to the formula, either sugar or jaggery or a mix of these is dissolved in water, boiled, filtered and added to the kvatha. If honey is used, it is added as such to the liquid without heating. (In the case of asava, fresh juices of herbs or fruits are used instead of kvatha.) Another group of herbs, collectively called Praksipa dravya, is made into a fine powder and mixed with the contents of the brewing tank. After this, Dhalakipuspa (flowers of Woodfordia fruticosa), if included in the formula, is properly cleaned and added. This initiates the fermentation process. The brewing vessel is closed tightly so as to avoid any contact with external air and left undisturbed. The bioactive ingredients from the herbs get extracted into the medium during the fermentation process. The progress of fermentation is monitored by measuring at regular intervals the alcohol content, pH, specific gravity, reducing sugar and non-reducing sugar. After the specified period of fermentation, the vessel is opened, and the contents examined to ascertain whether the process of fermentation has been completed. The fermented liquid is filtered through a muslin cloth or clarified using a centrifuge. The filtered arista or asava is thereafter bottled (Anonymous 1978c) (Figure 3.15). The master formula of Bhrngardjdsavam is presented to serve as an example (Table 3.7).