Bakhar: The Traditional Starter Culture of West Bengal

Bakhar is a traditional fermentation starter used by tribal communities in rural West Bengal, particularly the Santal tribe, to produce Haria, a fermented rice beverage. This indigenous starter culture is a remarkable example of how plant biodiversity is harnessed to create a complex microbial ecosystem for fermentation. Bakhar is not merely a yeast cake but a carefully formulated blend of rice flour and various plant parts, each selected for its specific contribution to the fermentation process and the medicinal properties of the final beverage.

Cultural Roots and Naming

Haria is a traditional fermented rice beverage commonly consumed by the tribal people of rural West Bengal. This beverage is prepared by fermenting steamed rice with the starter culture tablets known as Bakhar . The beverage is known by various names across different tribal communities, including Harla in Bengali or Handia in Hindi, and is an inexpensive beverage consumed as a staple food in lateritic West Bengal and many areas of East-Central India .

Production and consumption of Haria are common among the Santal tribe of Bankura district, West Bengal. During any festival, ceremonial occasion, rituals, social feasts, marriage feasts, and death feasts, sharing of Haria by the Adivasi community is a traditional culture. Other tribal peoples including Lodha, Kheria (Sabar), Munda, Kohi, Oraon, Mahali, and Bhumij of all ages regularly consume this drink . These groups mostly live near forests and depend upon this traditional beverage as a staple food as well as medicine. They also consume it as an energy-enriching drink .

The traditional starter used for Haria preparation is Bakhar (in Bengali) or Ranu tablet (in Hindi) . Bakhar is a mixture of old ferments containing microbial inoculums, parts of different plants, and rice dust .

Plant Ingredients of Bakhar

An ethnobotanical survey conducted among the Santal tribe documented the traditional knowledge regarding this ethnic beverage preparation. The survey revealed that 10 plant species and one lichen species are used by the Santal tribe to prepare the Bakhar . According to their habit, they are categorized into herbs (4), shrubs (2), climbers (3), trees (1), and one lichen species .

Among the 10 plant species, roots of Kedar, Chaoli, rhizome of Bach, and bark of Lodh plants are essential ingredients of Bakhar, while other plant parts are used due to their specific taste, flavor, and therapeutic properties . These essential plant ingredients and their scientific names are:

1. Kedar (Asparagus racemosus Willd.) - Root

2. Bach (Acorus calamus L.) - Rhizome

3. Chaoli (Ruellia tuberosa L.) - Root

4. Lodh (Symplocos racemosa Roxb.) - Bark

Additional plant species and parts used in Bakhar preparation include dried fruits of Piper longum L. (Piperaceae) and other plant materials .

A broader study on the ethnobotany of Bakhar in Paschim Medinipur documented that tribal people use 18 plant species as ingredients to prepare Bakhar tablets, depending on their availability and mostly collected from local forest areas . Among these 18 plant species, 14 plant species are also used by the Ojhas (tribal medicine men) in folk medicine for different ailments .

Another comprehensive list of plant ingredients includes:

· Cissampelos pareira L. (Akanbindi) - Root (main ingredient)

· Lygodium flexuosum (L.) Sw. (Kopulata) - Leaf and rhizome

· Orthosiphon rubicandus (D.Don.) Benth. (Chandua) - Root

· Ruellia tuberosa L. (Chaulia) - Root

· Terminalia alata Heyne ex Roth. (Asan) - Bark

· Xanthium strumarium L. (Agarstia) - Whole plant

Additional ingredients used for specific purposes include:

· Ananas comosus (L.) Merr. (Anarash) - Young leaves (sweetening agent)

· Artocarpus heterophyllus Lam. (Kanthal) - Leaves (produces yellowish tint)

· Centella asiatica Urb. (Thankuni) - Whole plant (aroma)

· Clerodendrum viscosum Vent. (Ghetu) - Young leaves (develops bitter taste)

· Coccnia grandis (L.) Voigt (Jangli-Kundri) - Tuberous root (develops sweetness)

· Costus speciosus (Koen. Ex Retz.) Sm. (Jamlakhoti) - Rhizome (antimicrobial preservative)

· Marsdenia volubilis Cooke. (Chit Larang) - Bark (develops bitter taste)

· Oldenlandia corymbosa L. (Banjaluk) - Leaves (imparting colour)

· Plumbago zylanica L. (Chitwar) - Leafy branch (process enhancer)

· Scoparia dulcis L. (Mithajangli) - Leafy twig (develops bitter taste)

· Stephania japonica (Thunb) Miers. (Dhal-ati) - Tuberous root (preservative)

· S. glabra (Roxb.) Miers. (Dhal-lata) - Tuberous root (preservative)

These plant materials provide not only the necessary microbial inoculum but also contribute bioactive compounds, flavors, colors, and preservative properties to both the Bakhar tablets and the final Haria beverage.

Rice Varieties Used in Bakhar Preparation

Nowadays, Santal people prefer Lal Swarna (Mtu 7029) rice variety. However, according to some elderly producers, in the recent past, local rice varieties like Danarguri, Bhutmuri, Masuri, Rupsal, Kelesh, Tulsibhog, and Patnai were used to prepare Bakhar and Haria . Unpolished and parboiled rice is soaked in water and pounded with Dieki (wooden mortar) by tribal ladies to make a fine powder .

Preparation of Bakhar

The preparation of Bakhar follows a traditional method passed down through generations:

1. Plant Material Collection: Plant parts are usually collected from local forests, washed with clean water, and dried under sunlight .

2. Powdering: After drying, the plant materials are ground to make powder .

3. Rice Flour Preparation: Unpolished and parboiled rice is soaked in water and pounded with a wooden mortar (Dieki) to make a fine powder .

4. Mixing: The rice flour and plant powder are mixed together .

5. Tablet Formation: A suitable amount of water is added to make dough. The mixture is formed into rounded tablets .

6. Incubation: The tablets are spread over straw beds in layers, with a final thin layer of straw cover. After 3 days, the tablets are picked up from the straw beds .

7. Sun Drying: The tablets are dried under sun for about 2 days .

8. Storage: The dried tablets are stored for use in fermentation of rice beverages .

During the survey, dried plant powder and ready-to-use starter tablets were observed being sold in village markets by Bakhar sellers . But nowadays little or no plant additives are used during commercial Haria preparation for cost-effectiveness, which may affect the quality and medicinal properties of the beverage .

Traditional Knowledge Transfer and Use of Bakhar Tablets

The knowledge of Bakhar preparation is passed down through generations and maintained by rural women, mostly by senior members of the family . The rural folk historically employed trial and error methods for improving the quality of the drink over time .

These tablets are not only used for fermenting rice beverages but also for treating various ailments. A paste of Ranu tablets with saliva is applied on mumps by the tribes before sleeping to get relief. Santals also disinfect tasar silk worm eggs during indigenous rearing .

Haria Preparation Process

The traditional preparation of Haria using Bakhar follows several steps:

1. Earthen Pot Sterilization: Earthen pots are cleaned using a bundle of rice straw and sterilized by direct heating and smoking .

2. Substrate Preparation: Low grade rice is cleaned and boiled to charring. Presumably, boiling kills pathogenic and undesirable microbes and enhances the availability of substrate .

3. Cooling and Drying: The parboiled rice (locally known as bhat) is air-dried under shade on a clean mat .

4. Starter Addition: 2-3 grams of Bakhar starter dust is mixed with 200 grams of parboiled rice. 8-10 Bakhar tablets are used for 1 kg of rice, which together produce about 10 liters of Handia .

5. Fermentation: The mixture is kept in a large earthen pot (Handi) followed by the addition of required water. The pot is closed with a lid and incubated for 3-4 days in a dark room .

6. Extraction: After fermentation, a white supernatant appears at the upper layer containing 8-10% alcohol, called Rashi, which fetches a higher price. The fermented liquid is allowed to trickle down through a bamboo sieve and is ready for consumption .

The taste of Handia depends on the plants used for Bakhar preparation . The quality gets lowered on dilution .

Physicochemical and Microbiological Characteristics

Studies on Handia have provided important insights into its composition:

· pH: The pH of the fermented substrate ranged from 4.24 to 4.67, indicating the acidic nature of the beverage due to lactic acid fermentation .

· Alcohol Content: The alcohol content of Handia samples ranged from 0.78% to 1.38% in consumable beverages , while other studies reported 2-3% (v/v) alcohol .

· Titratable Acidity: Average titratable acidity was 0.702 gm/L .

· Total Sugar: Average total sugar content was 1.359 gm/L .

· Protein: Average protein content was 0.675 gm/L .

Microbiological Analysis revealed:

· Lactic Acid Bacteria (LAB): Count ranged from 1.08 × 10³ to 9.84 × 10⁵ CFU/mL, with bacteria always more abundant than yeast .

· Fungi: Fungal counts ranged from 0.68 × 10³ to 7.37 × 10³ CFU/mL .

· This suggests that LAB dominate the fermentation process, contributing to the probiotic potential of the beverage.

Health and Functional Benefits

The Santals believe Handia possesses medicinal value, using it in the treatment of jaundice, colic disorders, and dysentery . In small quantities, these beverages are used as medicine for treating different ailments :

· Jaundice, Colic, and Dysentery: Handia is traditionally used to cure these conditions

· Sun Stroke Protection: It protects from sun stroke and maintains the motility and tone of the gastrointestinal system

· Nutritional Supplement: Tribals get 5-10% of their daily nutrient requirements from these beverages

Homemade vs Commercial Haria:

Research has revealed that homemade Haria contains more bioactive compounds than commercially produced versions :

· Ascorbic Acid: 15.40 mg/100 ml

· Flavonoids: 36.67 mg/100 ml

These bioactive compounds contribute toward the antioxidant property of the beverage. The difference is likely due to the fact that little or no plant additives are used during commercial Haria preparation for cost-effectiveness .

Social and Economic Significance

Haria and Handia hold significant social, cultural, and economic importance for tribal communities in West Bengal and East-Central India:

· Social Functions: It is used in all social, cultural, and religious purposes, and no social occasion is considered complete without it

· Marriages: In marriages, the amount of Handia to be given to the girl's side is decided well in advance

· Hospitality: It is offered to guests, gods, and deities

· Economic Livelihood: Handia preparation and selling is a secondary source of livelihood for tribals, and some accept it as a primary occupation

· Summer Drink: Consumption is much higher during summer (March to June), and it is essentially a summer drink

On average, some 30% of families prepare Handia for their own consumption, with per capita consumption amounting to about 1 liter per day . Women and children are also fond of these beverages but consume them in small quantities, preferably during festivals, ceremonies, and on Sundays .

Sustainable Use and Conservation

The traditional knowledge of Bakhar and Haria preparation relies heavily on the availability of forest plants. Many of these plants have medicinal values and are collected from local forests. Conservation of these plant species is crucial for maintaining this traditional practice and preserving the associated medicinal knowledge. The use of native plants in Bakhar preparation also demonstrates the importance of ethnobotanical knowledge in sustaining traditional food cultures.