Keywords

These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

6.1 Introduction

Sri Lanka is a teardrop or pear-shaped, elongated island, with a wider area in the south that narrows toward the north. The south central area is mountainous. It is located within the tropics, between the northern latitudes of 50 55’ and 90 51’ and the longitudes of 790 41’ and 810 53’ (Fig. 6.1). It has a land extent of 65,610 km2 and receives on average 2000 mm of rain annually (Statistical Abstract 2014). Major agricultural produce is rice which is cultivated during 2 seasons (Maha and Yala) of a year. Other crops include tea, rubber, and coconut, while other major food crops include millet (kurakkan), maize, cowpea, ginger, manioc, fruits, vegetables, etc. In addition, livestock, fish, milk, and eggs contribute to the dietary pattern (Statistical Pocket Book 2015).

Fig. 6.1
figure 1

Sri Lanka – land area by district (Source: http://www.statistics.gov.lk/Pocket%20Book/chap01.pdf – Statistical Pocket Book 2015)

Full size image

Population comprise of people belonging to many different ethnicities, majority being Sinhalese followed by Tamils, Moors, Burghers, and Malays (Statistical Abstract 2014). According to the Department of Census and Statistics report (2001) on the number and percentage of population by district and ethnic group, the Sinhalese are the majority group and account for 82 % of the total population. The Tamil community is 9.4 % of the total population and is subdivided into two groups: Sri Lankan Tamils and Indian Tamils (migrants from India). Muslims (8.2 %) are scattered around the country and comprised of Indian and Malay Moors. Burghers (0.2 %) are the descendants of the Dutch, Portuguese, and English who once colonized Sri Lanka and, by marrying Sri Lankans, settled in Sri Lanka (Department of Census and Statistics report 2001). Hence, the Sri Lankan cuisine is influenced by the Portuguese, Dutch, Malays, Arabs, and South Indians who have left their culinary characteristics and legacies.

6.2 Food Habits and Food Culture

Fermentation is defined as a desirable process of biochemical modification of primary food products (carbohydrates) brought about by microorganisms and their enzymes (Karovicova and Kohajdova 2005). This is a process that occurs naturally and part of the decay process, especially in fruits and vegetables. The health benefits and the enhancement of texture, nutritional value, taste, aroma, and longer shelf life are among the advantages of fermentation (Fellows 2000).

In Sri Lanka, even though not many fermented foods are available, some such foods have been used as a meal or part of a meal for a long time. The most well known is curd, made from buffalo milk, which has been a delicacy from ancient days. Fermented foods are fitted into the meal pattern in a variety of ways. Of the three main meals, lunch is invariably rice and curry, which comprises of a major portion of rice, one or two vegetables (green leafy vegetables, legume or potatoes, yams or tubers), and fish or meat curry made with condiments. However, most Buddhists avoid eating meat and Hindus avoid beef. Breakfast and dinner include other foods made with rice or wheat flour or bread. String hoppers, hoppers, roti, thosai, or idly, together with one or two side dishes, make the breakfast and dinner, of which some are fermented products. Especially thosai and idly together with wadai are common foods in the Tamil community. However, the foods that have been restricted to different ethnic groups have now become popular among all communities and available throughout the country.

Hoppers, thosai, idly, wadai, curd, toddy, jaadi (cured fish), lime pickle, dried fish, and bread (legacy from the European colonization era) are common fermented foods that have been utilized for a long time. However, yogurt, arrack, flavoring agents like vinegar, Maldive fish, newly developed vegetable pickles, salami, pepperoni, tempeh, and cheese are also commonly available. Today fermented fish sausages, fish sauces, and fish paste are entering the commercial market.

6.3 Milk-Based Products

The most common and popular lactic acid-fermented preserved foods among children and adults in Sri Lanka are yogurt and curd (Fig. 6.2), normally consumed as a dessert after the main meal. Both are characterized by a significant acidity caused by the production of lactic acid by lactic acid bacteria (LAB).

Fig. 6.2
figure 2

Curd (mee kiri)

Full size image

In curd (mee kiri or kiri) preparation, fermentation with lactic acid bacteria (Lactobacillus acidophilus, L. bifidus, L. bulgaricus) usually takes place with boiled cow or buffalo milk (Table 6.1). The milk is boiled, allowed to cool, and inoculated with a small amount of previous days’ culture as a starter and fermented for 24–72 h. LAB produce lactic acid and lower the pH, which, once reaching the isoelectric pH, causes casein precipitation forming curd (Wikramanayake 1996). Fermentation also results in a change in texture and increases the nutrient density. Curd made from buffalo milk, which is consumed with treacle, made from kitul (Caryota urens) palm, is the most popular form of fermented milk in Sri Lanka (Wikramanayake 1996). Buffalo milk gives a firmer curd than cow milk due to the warm dry conditions of the areas where buffalo milk is used in curd production. The minimum inoculum required for satisfactory curdling was 0.5 g of previously made curd or 34 × 106 colony-forming units (Pathirana et al. 1992).

Table 6.1 Some common ethnic fermented products of Sri Lanka
Full size table

Enzymatic methods of curdling also cause rapid clotting, but advantages of fermented milk are not found with these forms of curdled milk. The maximum recommended pH is 4.5 and lactic starter culture organisms isolated from curd are reported as L. fermentum, L. cellobiosus, Streptococcus lactis, and S. lactis subsp. diacetylactis (Pathirana et al. 1992).

6.4 Cereal and Legume Products

Fermentation due to lactic acid bacteria is a natural process brought about by LAB present in the raw food or those derived from a starter culture. Such bacteria in food fermentation of cereals are used in households of Sri Lanka from earlier days. Hoppers (appa) are based on a fermented batter, made of rice flour and coconut milk and pan fried. In hopper making, rice grains are soaked overnight, during which naturally occurring microorganisms will result in a population dominated by lactic acid bacteria. The grains are then ground and made to a smooth batter with coconut water and water. Fermenting agent could be toddy, a piece of bread, or yeast which is added to the mixture. The mixture is allowed to rise under normal aerobic conditions (8 h). Endogenous amylase will accelerate the fermentation. The pH produced will be 4.0 or less since cereals are weakly buffered. Hence, growth of bacterial pathogens will be inhibited. Just prior to preparation of hoppers, coconut milk is added and a batter made and cooked in a hot griddle. Hoppers are much like sourdough pancakes or muffins. If palm toddy is the fermenting agent (traditional way), this gives the hoppers a delicious liquor tang. Back sloping is a common practice in this type of food production at small scale or in households (Wikramanayake 1996). Hoppers can be either savory (egg hoppers, milk hoppers) which are eaten accompanied by lunu miris, a mix of red onions and spices or sweet (pani appa) made by adding jaggery. However, the instant flour mixtures are becoming more popular, but may not have the beneficial effects of fermented products.

Thosai and idly are common fermented foods eaten in Sri Lanka, a legacy from the South Indians who inhabit Sri Lanka. Black gram and rice are soaked separately for 4–6 h; mixed in proportion of 1:2 and mashed to a smooth batter and left overnight to rise (lactic acid production); flavored with fried shallots, curry leaves, fenugreek, and cumin; and cooked on a hot griddle greased with sesame oil for thosai or without condiments or steamed to make idly (Wikramanayake 1996).

6.5 Alcoholic Beverages

Toddy (palm wine; raa) is the traditional common fermented alcoholic beverage popular in the villages, made by the fermentation of the sap from coconut (Cocos nucifera) (Pol, Sinhala; Tennai, Tamil); the commonest, palmyra (Borassus flabillifer) (Tal, Sinhala; Panai, Tamil) (in northern parts); and toddy palm (Caryota urens) (fishtail; Kitul, Sinhala; Tippilipana, Tamil) (wet zone) (Samarajeewa 1986). The sap is collected by slicing off the tip of an unopened flower. The sap oozes out from the cut spadix and collected twice daily in a small earthenware pot tied underneath the flower. The fermentation starts as soon as the sap is collected in the pots on the palms, and after straining, the extract is sold on the same day in taverns and is referred to as sweet toddy. It is white and sweet with a characteristic flavor (4–6 % alcohol) and has a shelf life of about 24 h (Fig. 6.3). Fermented coconut toddy contains about 1.8–7.9 g alcohol, 0.29 g sucrose, 0.9–3.0 g invert sugar, and 3.72 g/dL total solids. Fermented sap also contains nitrogen, phosphorus, potassium, calcium, and magnesium <0.5 g/100 mL (Samarajeewa 1986).

Fig. 6.3
figure 3

Toddy (raa)

Full size image

The flavor is due to higher alcohols, aldehydes, ketones, and amino acids. More than 75 kinds of wild yeasts and bacteria in toddy have been identified. In fermenting coconut sap, 17 isolates of yeasts belonging to five genera were observed. They included isolates of Saccharomyces exiguus, S. cerevisiae, Pichia fermentans, S. rosei, S. fructuum, Torulopsis holmii, Torulopsis versatilis, Candida robusta, and Candida lambica (Jayatissa et al. 1978) and yeasts of Saccharomyces, Schizosaccharomyces, and Candida from coconut and palmyra palm wines (Liyanage et al. 1981). According to Vidanapathirana et al. (1983), coconut sap fermentation has three phases, in which the first phase (0–20 h) is dominated by bacterial fermentation (Leuconostoc, Lactobacilli, Streptococci, Bacilli, and Enterobacter) with a drop in pH from 7 to 4 with no alcohol formation. The second phase (30 h–5 days) is dominated by yeasts (Saccharomyces chevalieri) with Pichia (two strains) and Candida (two strains) with a subsequent increase in alcohol with no change in pH (4). Acetic acid bacteria dominate the third phase (Vidanapathirana et al. 1983). In the coconut sap, Saccharomyces chevalieri is the main alcohol-producing organism in contrast to Saccharomyces cerevisiae observed in many other alcoholic fermentation industries. Of the microorganisms isolated from the kitul palm, yeasts belonging to the genera Brettanomyces and Saccharomyces had been identified (Theivendirarajah et al. 1977).

Toddy, when fermented, becomes arrack (spirit), which comes in varying degrees of strength (Samarajeewa 1986). Toddy with an alcohol content of 6.7 % is distilled in copper or stainless steel plants to obtain arrack and stored in halmilla (Berrya cordifolia) vats for maturation (wood also adds a flavor component and color). The matured spirit is blended with water to obtain a final alcohol strength of 33 % by volume, and the product is bottled under various names depending upon maturation (Wikramanayake 1996). The quantity of ethanol produced had been shown to increase by adding the antifermenting agent sodium metabisulfite (up to 200 mg/l) during the collection of sap on the tree. This suppresses the non-ethanol-producing microorganisms and permits ethanol production by pure yeast cultures to different extents as coconut sap is the major raw material for the preparation of the toddy and arrack in Sri Lanka (Samarajeewa et al. 1985).

The production of beers is one of the well-established alcoholic fermentation industries in Sri Lanka with a history starting from 1860. The technology for the production is the same as in the Western countries. However, rice (dry milling) is also used in the beer production in addition to malt (wet milling). Milled starting material is mashed and conducted over a period of time at various temperatures in order to activate the enzymes responsible for acidulation of the mash and reduction of proteins and carbohydrates. The optimum pH range for mashing is maintained from 5.1 to 5.6 although values toward lower end (5.1–5.3) are considered optimum. After mashing, the liquid extract (wort) is separated (lautering) from the residual undissolved solid material of the mash. This will produce clear wort which is conditioned by boiling in the kettle. This will stabilize the wort and extract desirable components from the hops. This will allow sterilization (remove microorganisms which can result in off flavors), enzyme inactivation, protein precipitation, color development, production of melanoidins, removal of volatiles, and isomerization of alpha acid in hops into iso-alpha acid, a major contributor to bitterness in beer. Following boiling, the hop debris is separated and wort is cooled (to a temperature of 5–15 °C for bottom-fermented beers or 15–18 °C for top-fermented beers). After cooling, the wort is aerated to increase yeast activity and start the fermentation process. The yeast strain is a major contributor to flavor and character of the beer. Maturation involves secondary fermentation of remaining ferments at a lower rate. Finally beer clarification and stabilization are achieved by filtration (personal communication). The ethyl alcohol content (v/v) in different beers varies from 4 to 10 and pH is maintained at 3–4.8 (Samarajeewa 1986).

Illegally produced alcoholic beverage known as kassippu is produced with sugar as the starting material with yeast added for fermentation to proceed. People brew this for domestic consumption and for commercial purposes. Depending on the availability, fruits and other substances are added and the distillation is not properly controlled. It was reported that the brewers hang the herbicide, paraquat bottle with the lid pierced over the distilling cocktail, as they believe that condensed particles act as a catalyst, increasing the concentration and quality of the distillate (Dias 2010).

6.6 Vinegar

Vinegar, translated as sour wine, is one of the oldest products used by man. Vinegar is important as a highly effective food preservative and a flavoring agent. Coconut toddy vinegar is produced throughout South Asia particularly in Sri Lanka and has been used as a preservative of perishable food. Natural vinegar produced from coconut toddy is a household industry in Sri Lanka from ancient times using a traditional vat system (Food Processing Technologies 1995).

It is a clear liquid with a strong acetic acid flavor and a hint of coconut flavor (Fig. 6.4). Fresh toddy is strained and yeast fermentation is allowed to occur naturally for 48–72 h. The yeast (Saccharomyces ellipsoideus and S. cerevisiae) converts sugars to alcohol, which is the substrate required by the Acetobacter to produce acetic acid. After 2–4 weeks of settling, the fermented toddy is placed in barrels. Alcohol concentration of 10–13 % is ideal for vinegar production. High alcohol concentration will result in incomplete oxidation of alcohol to acetic acid, whereas lower alcohol concentration will cause loss of acetic acid due to oxidation after formation. The alcohol is oxidized into acetic acid, by acetic acid bacteria (Acetobacter acetic, A. xylinum, and A. ascendens), which are naturally present (Vidanapathirana et al. 1983). During maturing of vinegar, reactions between residual ethanol and acetic acid form ethyl acetate, which imparts the characteristic flavor to the product. The fermented toddy is converted into vinegar in about 3 months. Aging for 6 months results in a pleasantly flavored final product (Wikramanayake 1996; Battcock and Azam-Ali 1998). In addition to the above, vinegar is also produced by coconut water alcoholic fermentation and acetous fermentation with addition of sugar. The standards of composition of vinegar as specified should contain acetic acid not less than 45 m/v, with no mineral acids, and should be free of Turbatrix aceti (Food Act 2007).

Fig. 6.4
figure 4

Natural vinegar from coconut

Full size image

6.7 Vegetable and Fruit Pickles

Fermenting fruits and vegetables can bring many benefits to people in developing countries. Other than providing food security and improving the nutrition, such foods can be a source of good income when the waste is considered. Vegetables are classified as “low-acid” foods due to their low levels of acidity and are more prone to deterioration by microorganisms.

Lime pickle (lunu dehi) is an integral part of Sri Lankan cuisine. It is a method to preserve the excess of mature lime harvested during the seasons. The limes used are those that have turned yellow from ripening. The other main ingredient, an excess of salt crystals that the limes are stuffed with, acts as the preservative. Lime pickle is prepared by treating limes with dry salt. Limes are cut into quarters and placed in a layer, approximately 2.5 cm deep, into the fermenting container and salt added (4:1 ratio). The raw lime taste is avoided by prolonged drying in the sun ideally till its moisture content is removed and the core of the limes acquires a white coloration. The repeated drying in the sun allows the limes to marinade in salt. Salted dried lime is layered tightly until the container is three quarters full and covered with a cloth. The formation of brine takes about 24 h. As soon as the brine is formed, fermentation starts. Fermentation takes between 1 and 4 weeks depending on the ambient temperature. The final product is a sour lime pickle which can last for about 5 years. The methods of preparation vary, with the ingredients used and their quantities. Addition of vinegar, which also preserves the limes, gives the pickle the desired moisture as well. In addition, instead of chili powder, chili flakes and other spices such as cloves and cardamom as well for the preferred and desired final taste can be added (http://exploresrilanka.lk/2013/03/lunu-dehi-a-friendly-zest/). Spices are added depending on local preference. It is usually eaten as a condiment to enhance the overall flavor of the meal and is favored by many Sri Lankans (Wikramanayake 1996). A small amount of pickle makes a bland diet much more appealing.

Production of fermented capsicum using wet and dry salt method has indicated a salt concentration of 5 % and 5.5 % giving the lowest pH (3–4) following 12 days of fermentation. The microorganisms involved have been identified as Leuconostoc mesenteroides, Lactobacillus plantarum, L. fermentum, Pediococcus pentosaceus, Saccharomyces species, heterotrophic species Enterobacter cloacae, Citrobacter freundii, Micrococcus species, and Pseudomonas species (Mahinda 2005). However, following 6 months of fermentation, no microbes have been detected (Mahinda 2005).

6.8 Fish and Meat Products

All fermented fishery products in Sri Lanka are salt based. Of this, nearly 75 % is Maldive fish (umbalakada). This product is used to be imported from the Maldive Islands, but now most of it comes mainly from India and local production (Wikramanayake 1996). This is the lightly salted, smoked, dried loin of skipjack tuna. This is widely used as a flavoring agent in most local products/curries and is also said to have been used by Kandyan kings for flavoring their food (1700–1800 era; Edirisuriya 2003).

In the preparation of Maldive fish, skipjack tuna or other tuna varieties are deheaded and gutted and washed. Salt is added to the surface of fish and inside the horizontally cut areas and kept for 30 min. Fish is cooked as well as smoked for about 10–12 h or overnight. The cut pieces are separated from the central bone and all small bone scales are removed. The pieces are subjected to smoking for further 2–4 h. The smoked pieces are then rolled in ash and sun-dried for 7–10 days. Insufficient drying leads to extensive mold growth (State-of-the-art report on selected rural technologies 1995). According to a study with Maldive fish produced in Maldives, a higher percentage of (96 %) Maldive fish has been found to be contaminated with Aspergillus flavus (92 %), A. tamaraii (96 %), A. niger (40 %), A. ochraceus (12 %), and Penicillium citrinum (60 %). Quantification of aflatoxins from these samples had shown only 2 samples among 25 to be contaminated with above the legal limits (Mohamed 2013). Inhibition of fungal growth especially of Aspergillus flavus was achieved at aw 0.75, and this could be achieved by rapid drying. During the production of Maldive fish, toxigenic fungal growth needs to be controlled to avoid food safety risk (Mohamed 2013).

Dry fish marketed in Sri Lanka generally cannot be categorized as a fermented fishery product due to the process of salting involved and the fact that the product is in various degrees of fermentation. Fermentation will continue until water activity is decreased due to drying. Drying method varies with size of fish, and for small fish, sun-drying is preferred and slat-drying (common during rainy season) is preferred for large and moderately fatty fish. Ventral side is split in smaller fish, whereas dorsoventral splitting is used for large fish, where gills and intestines are removed, washed, cleaned, and spread out at the time of drying (Subasinghe 1993).

Jaadi or pickled fish (Fig. 6.5) is the other important fermented fishery product and is mainly produced locally on a cottage scale. Jaadi is a wet-cured traditional fermented fishery product (Weerasinghe 1991). Indian mackerel is the commonly used fatty fish in the preparation of jaadi in Sri Lanka especially during the glut. Jaadi is a highly salted fermented fishery product consisting of partially hydrolyzed fish flesh where the organs are immersed in the liquid exudates from fish. A low pH (below 4) is maintained by the addition of ripe pods of goraka (Garcinia cambogia) (Jayasinghe et al. 2000). The curing mixture is made using dried and ground goraka (G. cambogia) and solar salt (ratio varies). Indian mackerel treated with solar salt in the ratio of 3:1 and by keeping the ratio of fish/goraka to 10:1 is reported (Jayasinghe 2002).

Fig. 6.5
figure 5

Pickled fish (jaadi)

Full size image

Deskined tilapia (Oreochromis niloticus) fish without head has also been used effectively to produce jaadi. A ratio of 500 g of goraka (G. gambodiea) and 100 g of salt with 1 kg of tilapia has produced jaadi with acceptable sensory properties (Lakshmi et al. 2010). Production of jaadi from tilapia is considered beneficial to overcome the postharvest losses and increase consumption due to lack of taste leading to less popularity among consumers. Presently this is done as a cottage industry along the coastal area, but the product is not produced under standard conditions; hence, the popularity is less.

Salami and pepperoni produced by using starter cultures (Pediococcus pentosaceus) on meat are also gaining popularity though they are not traditional products. Meat is cultured with starter cultures and frozen and kept at room temperatures for 3 days and put in a steam chamber (35–40 °C, 3–4 h) and in a controlled atmospheric room (3 weeks) where the temperature and relative humidity are gradually decreased. Depending on the temperature and the relative humidity and the time, salami (5 weeks) or pepperoni is produced. In addition to flavor acquired by bacterial fermentation, artificial flavors are added (personal communication).

6.9 Biochemistry or Nutritional Composition

Very limited data are available on the nutritional quality and biochemical activities of Sri Lankan fermented food products. Most work has been conducted on curd and yogurt, the most popular forms of fermented food products.

6.10 Milk Products

Nutrition-wise, curd and yogurt are both rich in B vitamins and have high protein content that enhances the bioavailability of calcium and are a food for lactose intolerants. Curd from buffalo milk is rich in fat and calcium and sets harder than cow’s milk. Set yogurt and fruit yogurt manufactured by different manufacturers on an average had protein contents of 4.0 % and 3.0 %, respectively. Ash and fat contents varied from 0.77–1.3 % to 0.40–3.94 % with fruit-containing samples having a low fat percent (De Silva and Rathnayaka 2014).

The ACE inhibitory percentages of the bovine full-fat milk samples fermented with L. lactis subsp. lactis NBRC 12007 and S. cerevisiae K7 monocultures and the coculture were 33 %, 27 %, and 25 %, respectively (Rasika et al. 2015). The results conclude that the two strains tested were able to hydrolyze milk proteins into ACE inhibitory peptides. It is suggested that these strains be successfully utilized in the dairy industry in manufacturing fermented milk products with ACE inhibitory activity as a dietary supplement and/or as an alternative approach for antihypertensive medication (Rasika et al. 2015).

6.11 Jaadi

A total of 40 samples of different varieties of fishes collected from the market and jaadi curing yards when evaluated for quality and fungal and insect infestation showed that jaadi had a high level of protein. However, the defects of curing process such as inadequate cleaning and salting resulted in low-quality (chemical and microbiological) products (Jayasinghe et al. 2000). The total bacterial count (TBC), oil content, free fatty acid (FFA), peroxide value, and pH of jaadi made with Indian mackerel cured for 1 day were 1.42 × 103, 2.2 %, 29.9 %, 0 %, and 2.42 %, respectively (Jayasinghe et al. 2003). However, the overall acceptability was unsatisfactory (2.5). After 2 months of curing, the FFA, peroxide value, oil, TBC, pH, and overall acceptability of jaadi were 19.71 %, 0 %, 2.24 %, 1.82 × 103, 3.29, and 5 (best quality), respectively. The changes in oil, peroxide, and FFA indicated that oxidation has not occurred during the first 2 months (Jayasinghe et al. 2003). Further studies on nutritional profile of jaadi made with Indian mackerel indicated little change in fat content during a period of 4 months. Among lipids, triacylglycerols dominated the other lipids and lipid-soluble compounds. However, the content of fat can be influenced by the species, season, geographical region, size, gender, age, and maturity. The saturated fatty acids in jaadi decline during storage with no change in monounsaturated fatty acids and n-6 PUFA, but a gradual increase in n-3 PUFA is observed. A distinct decline in cholesterol (35.2–11.2 mg/g lipids) has been observed with pickling time with an increase (Ubhayasekera et al. 2005) in the cholesterol oxidation products (COPs) up to the sixth week and a gradual decline during further storage. Oxycholesterol metabolites are considered to be potentially involved in the initiation and progression of major chronic diseases including atherosclerosis, neurodegenerative processes, diabetes, kidney failure, and ethanol intoxication (Sottero et al. 2009). Therefore, regular consumption of pickled fish that has been cured for over 2 months can be a source of considerable amounts of COPs in the diet of the local population in Sri Lanka (Ubhayasekera et al. 2012).

Salted dried fish is also consumed in small quantities after deep frying or as a curry with rice. The composition varies widely with moisture varying from 10 % to 55 % and salt from 1.5 % to 5 %. Drying causes loss of vitamins but the protein content is higher than fresh fish ranging from 25 % to 30 % (Wikramanayake 1996).

6.12 Ethnical Value and Socioeconomy

Curd (mee kiri or kiri) production in some parts of the country is conducted as a cottage or small-scale industry. The traditional method of production is followed and curd is available in clay pots (Fig. 6.2). In the south and southeast of Sri Lanka, coverage of 84 % of 2 districts has indicated that 1968 producers produce 20,000 pots of curd per day (Pathirana et al. 1992). This has now increased considerably. Especially in the south and east of the country, this is a form of fund generation. It is indicated that by introduction of low-cost, simple, scientific production methods, the quality and hygienic standards of the curd could be improved. Currently large dairy production companies have also entered the market to meet the consumer demand. The largest alcoholic beverage industry in Sri Lanka today is the coconut sap fermentation industry which produces toddy and the distilled beverage “arrack.” Toddy is bottled and pasteurized to improve the shelf life. These beverages are popular due to the characteristic flavor and the low cost. The other popular beverage in Sri Lanka is beer. Of the three, the coconut is tapped industrially in large scale in the areas of the western coastal belt. The inflorescence of the palmyra palm is tapped in the Jaffna Peninsula and to a small extent in the east coast of Sri Lanka. Fishtail palm is not grown in large scale but is tapped wherever it is available. It exists as a cottage industry for the production of toddy and as a source of sugars, treacle, and jaggery (Chrystopher 1988). The brewery industry has captured the export market with a variety of beers (lager, stout, beer) and caters to local demand as well. The largest one is equipped with state-of-the-art manufacturing facilities that enable it to fulfill the increasing demand and export beer to new and current export markets, such as England, Japan, and Australia.

Manufacture of different cheeses is another industry that has gained value during the last 25 years with few major and small manufacturers producing to cater to the consumer demand. Over 90 % of the cheese in Sri Lanka is imported; however, the cheese produced by these manufacturers is gaining recognition and some are able to provide rural women with an income. Some small-scale manufacturers adjust the textures, flavors, and also packaging size and modes according to the demand and thus are able to sell these domestic cheeses at highly competitive prices. Through this process, women are empowered by giving them access to the market to learn valuable farming and monetary skills and providing them with the reliable income they need to gain financial stability. Vinegar production has also captured the export market and is a source of foreign revenue in Sri Lanka. Fermented foods as functional foods are gaining importance all over the world, and increasing the awareness of such products among the general population is important. Major benefits include enhancement of nutritive value by increasing digestibility, inhibition of growth of most pathogenic bacteria, inhibition of formation of bacterial toxins, and degradation of plant toxins (cyanogenic glycosides). The health benefits (reduction in gastrointestinal disorders such as diarrhea, gastritis, and peptic ulcers, inhibition of cholera bacteria) that can be obtained by consuming such products are not well publicized and hence not known by many people in Sri Lanka. However, in the modern world, people tend to buy convenient foods off the shelf, which are easy to prepare. Therefore, it will be relatively easy to popularize some of these products if they are produced under standard hygienic conditions. More research is needed to identify the lactic acid bacteria in Asian fermented foods and their physiological functions in the human diet.