CHAPTER - II REVIEW OF LITERATURE 2.1. CEREALS AND MILLETS – SUBSTRATE FOR FERMENTATION Cereal and millets form the basic diet for millions of people throughout the world. They are major sources of inexpensive dietary energy and nutrients worldwide. When compared to other fermentable substrates, cereals and millets are superior in nutritional quality as these abundant resources contain some of the essential minerals, vitamins, sterols, growth factors and dietary fibres thus satisfying essential nutrient needs of mankind. However, presence of some of the anti-nutrient factors such as phytic acid affects the availability of minerals. Also, the absence of certain essential aminoacids in cereals makes them inferior to other substrates. The sensorial properties of products from cereal and millet based are affected due to the presence of tannin and polyphenols and coarse nature of grains (Chavan and Kadam, 1989). Though various ways were adopted to overcome these limitations, fermentation seems to be the best and inexpensive way to improve the nutritional and sensorial quality of cereals. Fermenting cereals and millets offer several advantages such as reduction in the level of anti-nutrients (Oyewole, 1997, Mugula et al., 2003, Hamad and Fields, 1979, Sanni et al., 1999) and improvement in mineral availability of the cereals (Khetaurpaul and Chauhan, 1991). Generally, fermented cereal and millet products have enhanced aroma and texture which improve the palatability of the products. For some of the cereal and millet substrates, fermentation forms the only option as it eliminates toxins and makes the substrate fit for consumption (Vasconcelos et al., 1990). Along with the essential nutrients, cereals and millets also contain appreciable amounts of phytochemicals such as phenols, tannins and flavonoids. Earlier they were considered as anti-nutrients but in recent years phenolic acids are reported to act as antioxidants by donating electrons (Chandrasekara and Shahidi, 2010). Several reports stated the anti-mutagenic, antimicrobial effects of phenolic acids present in cereals and millets (Jones and Engleson, 2010). These bioactive compounds were mainly concentrated in the seed coat of the grains and their levels vary among cereals and millets. These compounds may act either as inhibitor or as enhancer based on 6 their bioavailability and processing methods. The composition of cereal and millets are presented in Table 2.1. Table 2.1 Composition of cereal and millet grains Constituent Dehulled cereal Dehulled millet content content (% dry weight basis) (% dry weight basis) 45-77 16 - 45 Polysaccharides Starch Dietary fibre (as non starch 9 - 15 3.6 – 9.8 polysaccharides and lignin Sugars Fructose 0.1-0.4 0.12 – 0.23 Glucose 0.1-0.5 0.10 - 0.25 Sucrose 0.5-0.2 0.22 - 1.68 Raffinose 0.2-0.7 0.04 - 0.71 Stachyose - 0.06 - 0.13 Proteins 8-15 7.3 - 12.5 Lipids 2-6 0.7 - 1.7 Ash (minerals) 1.5 – 3 0.6 - 2.8 Source: FAO, 2008, Salovara et al., (2003) Other than these nutritional advantages, cereals and millets contain prebiotic components which support the survival of functional microbes in gastric transit. Short oligosaccharides, resistant starch, polysaccharides and dietary fibres are recognised as prebiotics (Macfarlane et al., 2006). Any cereal substrates naturally contain at least two of the oligosaccharides (Henry and Saini, 1989) which possess different physiological functions. Also the presence of resistant starch and dietary fibres in cereals serve as encapsulation materials for probiotic microbes. Cereals and millets form very good substrates for various groups of microorganisms. Generally indigenous cereal and millet fermentation is spontaneous microbiological process hence involves complex microbiota. However due to 7 molecular development in molecular biology techniques biodiversity of various fermented foods are revealed which lead to the better understanding of the fermentation process and controlled fermentation process was developed for some of the indigenous fermented foods. The review discusses the role of microflora in cereal and millet fermentation and the benefits offered by them in the substrates due to their metabolic activities. 2.2. MICROBIOLOGY OF CEREAL AND MILLET FERMENTATION Microbial diversity of cereal and millet based fermented foods range from LAB to endopsore-forming bacteria, amylolytic and alcoholic producing yeasts and filamentous moulds. Raw cereals and millets contain surface microflora which are activated when water is added to the substrates. Microflora also derived from various sources such as raw materials, utensils/ equipments and food matrix (Jespersen et al., 2003). The establishment of particular microflora in the substrate depends on water activity, pH, food matrix composition, salt concentration and method of preparation. During spontaneous fermentation microbes either occur in succession or co-exist with other microbial groups in synergistic effect. For example, yeasts multiplication is favoured by acidic environment developed due to metabolic activities of LAB while bacteria growth is favoured by the yeast activities as it provides several growth factors such as vitamins, minerals and nitrogen compounds during fermentation (Nout, 1989). However dominance of particular strain during fermentation results due to competitive abilities of the strain in the substrate. The predominant organisms reported in all cereal and millet fermentation are LAB and yeasts. 2.2.1. LAB IN CEREAL AND MILLET FERMENTATION LAB occupies most important part in all cereal and millet fermentation. LAB strains are given the status of GRAS (Generally Regarded as Safe) because of long history of use in food industry (Wood and Holzapfel, 1995). They are one of the most important groups of microorganisms in food fermentations (Abriueol et al., 2011). LAB strains are capable of lowering the pH to below 4 in cereal based food products thus preventing spoilage of foods and contributes largely for aroma formation in cereal products. Due to this property, other non acid producing organisms were eliminated making LAB as predominant organism in most of the fermentation process 8 (Nout et al., 1989, Brauman et al., 1996). Cereal fermentations are mainly dominated by four different genera of LAB such as Lactobacillus, Lactococcus, Leuconostoc and Pediococcus (Salovaara, 1996). Keeping in view of the vast biodiversity of LAB in various food products and to understand the roles of LAB in fermentation processes, physiology, genetics and applications of LAB were studied extensively. As fermentative nature of LAB is diverse and has significant impact on foods to develop a better controlled process some of LAB genomes have already been published. Earlier identification of LAB species was based on biochemical characteristics such as morphology, growth characteristics and mode of glucose fermentation which enabled identifying LAB isolates at genera level. These characters were still considered essential in classifying LAB isolates. Recent years have seen an explosion in the development and application of molecular tools for identifying microbes and analyzing their activity. These tools are increasingly applied to strains of LAB at species level including those used in fermentation as well as those marketed as probiotics. 16S rRNA sequence analysis emerged as a powerful and reliable technique for identifying and determining the phylogenetic relationships of LAB strains (Schleifer et al., 1995, Morelli et al., 2004). Another widespread molecular technique used for LAB identification is Random amplified polymorphic DNA (RAPD) (Hamza et al., 2009, Mora et al., 2000). RAPD sequencing was used for monitoring progress of LAB starters during fermentation and for determining similarity among the LAB isolates (Corsetti et al., 2001, Antonsson et al., 2003). With new developments of molecular biology and to overcome limitations of culture dependant techniques, Denaturing Gradient Gel Electrophoresis (DGGE), a culture independent technique were successfully applied on fermented cereal foods (Meroth et al., 2003). DGGE presents a clear picture of microbial diversity in fermented foods. However identification of predominant strain during fermentation is difficult with this technique. Another culture independent technique, Pulsed field gel electrophoresis (PFGE) allows the separation of large DNA fragments PFGE protocols were well established for LAB strains but due to labor intensive technique it is not feasible for large scale typing of isolates. Rep PCR technique is being recently used widely for identification of LAB to sub species level (Ab) (Towner and cockayne, 1993). 9 Though several identification methodologies were proposed for LAB the choice of identification methods depends on the fermentation medium and purpose of identification. In practice for identification of large number of isolates, a combination of phenotypic, biochemical and molecular methods was found to be effective (Kunene et al., 2000). 2.2.2. YEAST IN CEREAL AND MILLET FERMENTATION Yeast was found along with LAB in almost all cereal and millet fermentations (Oyewole and Odunfa, 1990, Halm et al., 1993, Hounhouigan et al., 1993). Significance of Yeast was well reported in Ogi and Kenkey by Jespersen et al., (2003). In many of the Asian fermented foods, yeasts were reported to be predominant and functional during fermentation (Aidoo et al., 2006). Yeast contributes significantly for structural quality and organoleptic characters of the product. The sugars formed during fermentation were utilized and converted to main end product, ethanol. Yeast strains reported to exhibit wide range of enzymatic activities and also produce flavour compounds such as alcohols, acids, esters, terpenes and lactones during cereal fermentation (Jansens, 1992). Also yeasts strains contain high content of protein, lipids and micronutrients which greatly help in reducing prevailing micronutrient deficiencies in rural set up (Mai et al., 2002). The predominant strains reported from fermented cereals were Saccharomyces cerevisiae, Geotrichum candidum, Candida grusei and Candida tropicalis. Identification of yeast colonies in fermented foods were done by biochemical methods as described by Kreger van (1984) and Barnett et al., (1990). The tests include colony and cell morphology, sporulation, fermentation tests and pseudomycelium formation (Dalmau spot-plate technique). Depending on the carbohydrate assimilation pattern some of the yeasts organisms were identified and for this purpose ID32C kits were widely used. Recently molecular based methods such as rRNA sequencing, PCR-DGGE, Rep PCR analysis were also adopted for yeast identification (Botes et al., 2007). 2.2.3. FOOD BORNE PATHOGENS Other than these predominant microbial groups various enteropathogens were found to be associated with cereal and millet fermentation. As they occur as seed 10 microflora pathogenic groups were inevitable during cereal and millet fermentation. But reports stated the reduction in pathogenic groups due to LAB and Yeast dominance. The review further presents the nutritional and functional role played by predominant microbes in cereal and millet fermentation. 2.2.4. ROLE OF MICROBES IN IMPROVING NUTRITIONAL QUALITY OF FERMENTED FOODS As already stated, though cereals and millets are high in nutritional quality the presence of antinutrient factors hinders their utilization. Various reports stated the role of LAB and yeast strains in improving mineral availability of fermented millet and cereal based products. Khetaurpaul and Chauhan (1990) reported increased mineral availability during pearl millet fermentation effected by pure cultures of LAB and yeasts. LAB and yeasts were also reported to exhibit various enzymatic activities during fermentation. The level of carbohydrates and polysaccharides gets reduced due to amylolytic activities of LAB (Oyewole, 1997). Proteolytic activities of microbes during fermentation led to the availability of peptides and amino acids and improves protein digestibility of the substrates (Mugula et al., 2003). Some of the LAB strains were reported to improve riboflavin, thiamine, niacin and lysine contents during millet fermentation (Hamad and Fields, 1979, Sanni et al., 1999). The duration of the fermentation, method of indigenous processing and microbial activities were reported to significantly alter bioactive components of the substrate. During natural pearl millet fermentation, decrease in polyphenolic content was reported by Elyas et al. (2002) whereas during finger millet fermentation increase in polyphenolic content was reported by Sripriya et al., (1996). Banu et al., (2010) stated that type of fermentation and the metabolic activities of LAB were responsible for the increase in levels of bioactive compounds and antioxidant capacity of rye bread and rye sourdough. Some of the cereal fermentation utilising LAB as starters have shown improved antioxidant property (Dajanta et al., 2011). Also the processing methodologies, such as decortications of sorghum, drastically reduced antioxidant property of the grain and its health properties. Thus the antioxidant property of cereals and millets were altered in either way during fermentation by several intrinsic factors. 11 2.2.5. FUNCTIONAL ROLE OF PREDOMINANT MICROBES IN CEREAL AND MILLET FERMENTATION Definition for functional foods given by Hugett and Schliter (1996) says “foods or food ingredients that exert beneficial effect on host health or reduce risk of chronic disease beyond basic nutritional functions”. Probiotic foods are regarded as functional foods as they include functional microbes which provide beneficial effects to consumers by improving microbial balance in intestinal tract (Fuller, 1989). Today many specific strains of Lactobacillus, Bifidobacteria, Bacillus and yeast are regarded as commercial probiotics. However, lactobacilli still remain the most commonly used probiotic microorganism (Holzapfel and Schillinger, 2002, Saxelin et al., 2005). Due to increased awareness on probiotics, many proven and approved probiotic strains are available in market as supplements in dehydrated form. But fermented foods serve as common carriers of probiotic microbes since they support growth of these organisms. For many years, there was much emphasis of incorporating probiotic LAB cultures on dairy products such as milk (Antunes et al., 2009) yogurt (Aryana et al., 2007) and cheese (Burns et al., 2008). Many dairy products are optimized for survival of probiotic organisms and marketed successfully. Probiotic strains were successfully used as starter cultures in dairy foods which lead to the production of novel types of fermented milks and cheeses (Gomes and Malcata, 1999). Recently owing to increased awareness in probiotics, inclusion of probiotic strains in cereal and millet fermented substrates was actively investigated. Previous reports of indigenous cereal and millet fermentation have mentioned anti-diarrhoeal functions of some of the product (Mensah et al., 1988, 1990, 1991, Nout et al., 1989, Odugbemi et al., 1991, Kingamkono et al., 1998, Kimmons et al., 1999, Tetteh et al., 2004). The microbe involved during fermentation process could be probiotic as ability to decrease the incidence or duration of certain diarrhoeal illnesses is considered as the most substantiated probiotic health effects. The fermented Mahewu showed reduction in level of pathogens such as Salmonella, Shigella, Campylobacter, Aeromonas and pathogenic E. coli which indicated the presence of LAB strains with potential probiotic properties in traditional fermented preparations (Simango, 1997). The reports of Kingamkono et al. (1998) suggested that the traditional cereal fermented foods are good carriers of probiotic microbes. He reported that Togwa, maize and finger millet based East African 12 traditional food inhibited growth of enterotoxin producing bacteria. Significant reduction of enteropathogen population was noticed in rectal swabs of children under five years old when they fed with togwa. Lei and Jakobsen (2004) isolated LAB strains such as Weisella confusa and Lactobacillus from koko sour water which exhibited antimicrobial activity against the pathogen Listeria. Part of fermented portion of koko sour water was used to treat patients with upset stomach which was also used as refreshing drink instead of water. According to Vogel et al., (1993) some of LAB strains in sourdough and in fermented cereal foods were identical to species found in animal and human intestinal tract. The report open up another possibility of introducing human derived probiotic strains into cereal based traditional food. Cereals and millets naturally possess prebiotic fibres thus readily support the growth and survival of probiotic microbes in gastrointestinal tract (Charalampopoulos et al., 2002). Hence cereal and millet based products with probiotic microbes can be called as synbiotics. As cereals and millets support growth of functional LAB strains, development of non-dairy probiotic products will helps in better utilisation of these abundant resources. With this view one of the popular traditional cereal based fermented food, ogi has been modified with functional properties by introduction of probiotic starters with antidiarrheal properties (Okagabue, 1995). Also a newly developed oat based fermented product, Yosa which is familiar in Finland regions contain probiotic lactic acid bacteria which was reported to improve the intestinal environment (Toufeili et al., 1997). Thus fermented cereal and millet foods form very good alternative to dairy probiotic foods and infact superior to dairy foods as it is encompasses prebiotic benefits. This property proves that the potential for using cereal and millet based indigenous fermented product for probiotic treatments is huge. 2.2.6. LAB AND YEAST – IMPROVING SAFETY OF FERMENTED FOODS Traditional fermentation process is generally considered as an inexpensive way to improve the safety of foods. As most of cereal and millet fermentation was carried out in rural households basic hygienic practices are not generally observed. However, safety of the fermented foods was ensured by metabolic activities of microbes in the substrate. Fermentation forms the affordable way of improving safety of the traditional fermented foods. The preservative properties of fermented foods is 13 attributed to microbial activities such as organic acid production (Ali et al., 2003, Mugula et al., 2002, Lei and Jakobsen, 2004), alcohol production, hydrogen peroxide formation (Kullisaar et al., 2002), carbon dioxide production (Adams and Nicolaides, 1997, Caplice and Fitzgerald, 1999), bactericidal compounds production and competition among the microbes which leads to nutrient depletion. Acid production of LAB was reported to be more effective towards gram negative pathogens compared to gram positive organisms (Mensah et al., 1991). Carbondioxide production by heterofermentative LAB organisms during fermentation creates an anaerobic environment thus indirectly inhibits aerobic spore forming organisms during fermentation (Devlieghere, 2000). Under natural conditions, production of hydrogen peroxide creates structural damages and changes in bacterial membranes thus inhibit microbial activity. Another preservative mechanism of cereal fermentation which is very well studied is the production of bactericidal compounds (Omar et al., 2000, Riley and Wertz, 2002). Almost all gram positive strains were reported to produce bacteriocins. However, bacteriocins produced by LAB isolates are very well studied and understood. Bacteriocins appear to have narrow spectrum activity which acts as a protective mechanism of fermented foods in household conditions. Cereals support growth of mould and thereby mycotoxins are produced by naturally occurring fungi that grow on a wide variety of grains. Mycotoxins cause harmful effects to human when they are metabolically active in foods. According to reports of Teniola et al. (2005) and Alberts et al. (2006) lactic fermentation was effective in reducing mould growth and LAB strains has the capacity to inactivate mycotoxins during fermentation. Thus lactic fermentation forms the only way to improve the safety of cereal and millet based foods in rural set up. On the other side as stated by Bhalla et al. (2008), microbial safety of fermented foods observed in vitro is not always apparent because a lot of intrinsic factors are involved during processing at the household level especially with porridges, where large quantities of water are added during preparation. Hence, individual field trials are necessary to ensure the safety of fermented foods. The review further summarises popular cereal and millet based fermented foods produced in Africa and India and microbiology involved. 14 2.3. CEREAL AND MILLET BASED FERMENTED FOODS All around the world, cereal based fermented foods and beverages form part of the human diet. Different varieties of cereal and millet based fermented foods are prepared in different parts of the world. Some are utilized as colorants, spices, beverages and breakfast or light meal foods while a few of them are used as main foods in the diet. The production technologies and substrates vary according to geographical locations and some of the preparations utilises several fortifying substances to enhance taste and nutrition. In western countries cereals like wheat and rye are preferred for consumption whereas in African and Asian countries cereals like rice, wheat and maize and Sorghum were used for breakfast or light meal preparations and millets were used for preparation of sour porridges and dumplings. As per the documented information (Blandino et al., 2003) cereal and millet fermentations were carried out in African and Asian countries in daily basis. 2.3.1. CEREAL AND MILLET BASED FERMENTED FOOD FROM AFRICA Some of the popular cereal based fermented food which are widely studied and documented from African countries includes Ogi, Koko, Kenkey, Uji, Mawe,Tting, Koko sour and Mahewu. Table 2.2 lists some of the reported indigenous cereal and millet based preparation of African countries and the microflora involved in the fermentation process. The fermented preparations of Africa largely include sorghum and Maize in food preparation and occasionally rice and wheat. Natural fermentation is commonly practiced for preparation which utilises microbes occurring naturally in the substrate and in environment (Oyewole, 1997). In some places, backslopping is done to speed up the fermentation process which utilises residue from the previous batch (Holzapfel, 2002). Using fermented foods as weaning products is widespread in Africa (Lorri and Svanberg, 1995). The probiotic and antimicrobial potential of some of the African traditional foods like koko sour porridge and Ogi was reported. Ethnic foods also form a source of revenue for many rural African people to sustain their livelihood. In recent years, starter culture technologies have been developed for some of the processes such as Togwa, Ting and Ogi. 15 Fermented product Substrate Mahewu/Zulu/ Maize and Sorghum, Amahewu Millet and wheat flour Ogi/ Adifi/Akamu Maize Microorganisms involved in process Process Reference Spontaneous Chavan and Kadam (1989) fermentation Odunfa et al., (2001) L. plantarum, Saccharomyces cere- Spontaneous Calderon et al., (2003) visiae, Candida mycoderma fermentation/ Lactococcs lactis Backslopping Uji Kenkey Maize and Sorghum L. plantarum, L. cellobiosis, L Spontaneous Mbuga (1984) Cassava and millet flour buchneri Maize L. palntarum, L. confusus, L brevis, Processing Jespersen et al., (2003) Pediococcus pentosaceus, Sacchro- involves fer- myces cerevisiase, Candida mentation and heating and steaming cycles Busa Maize and finger millet L. helveticus, P. damonsus, S. cere- Spontaneous visiae, C. krusei, fermentation Nout, 1991 process Togwa Sorghum, Maize L. brevis, L. cellobiosus, L. fermen- Spontaneous Mugula et al., (2002) tum, L. plantarum, Ped. Pentosaceus, Candida pelliculosa, C. tropicalis, 16 Umqombothi Maize and Sorghum Candida haemuloni, C. sorbophila, Spontaneous Joseph, 2008 Debaryomyces hansenii, S. capsularis, S. Cerevisiae Ben saalga Pearl millet LAB and yeast Spontaneous Tou et al., 2006 Dolo/Pito Sorghum Saccharomyes cerevisiae, L. fermen- Spontanous/ Sawadogo et al., 2008 tum backslopping Lactococcus lactis, Lactobacillus Spontaneous fermentum, Lactobacillus plantarum, fermentation Ting Sorghum Evelyn et al., 2011 Lactobacillus rhamnosus, Weissella cibaria, Enterococcus faecalis Kunun-zaki Millet L. fermentum, L. leichmanni, S. Cer- Backslopping/ evisia Spontaneous Adeyemi & Umar, 1994 fermentation Mawe Maize L. fermentum, L. reuteri, L. brevis, Spontaneous L. carvatus, L.buchneri, fermentation Hounhouigan et al., 1993 P.acidilactici, Strep. lactis, L. salivarius, Weissella confuse, yeasts Kisra Sorghum P. pentosaceus, L. brevis, Yeasts Spontaneous (D. hansenii, C. intermedia), fermentation/ L.fermentum, Backslopping Mohammed et al., (1991) 17 2.3.2. CEREAL AND MILLET BASED FERMENTED FOODS FROM INDIA India is a land of diverse culture and tradition. Traditional preparatory processes utilises a wide range of raw materials and production processes, leading to the production of diverse products. Indian fermented foods mainly involve rice and wheat as fermenting substrates. Some of the fermented preparations also utilises combinations of legumes and millets. The review presents the range of popular indigenous cereal and millet based fermented food consumed in north and southern parts of India. North east region of Indian subcontinent can be complimented for treasure of traditional knowledge as it forms home for more than 166 separate tribes speaking a wide range of languages (Tamang, 2012). This range of communities and its geographical and ecological diversity makes North East India significantly different from the other parts of Indian subcontinent. The tribal groups traditionally produce a variety of fermented foods and beverages and also market them locally. The sub-tropical climate of North Eastern India is extremely favourable for the cultivation of many crops. The seasonal crops are preserved by the local women either by sun drying or made into fermented pickles. There are various ethnic fermented foods that are prepared and processed by different tribes of North East India that describe their socio-cultural, ecological, and spiritual life. The processing and preparation of ethnic foods demonstrate the creativity and treasure of food heritage (Anamika et al., 2007). The Himalayan dietary culture has both rice and wheat or barley or maize as staple food along with varieties of ethnic fermented and non-fermented foods prepared from soybean, vegetable, bamboo, milk, meat, fish, alcoholic beverages, and wild edible plants (Tamang, 2010a). More than 250 different types of ethnic fermented foods and alcoholic beverages are prepared and consumed by the ethnic people of Himalayan region (Tamang et al., 2012). Different types of substrates and fermenting organisms are being employed for the production of these ethnic food products. In the Himalayas, ailing persons and post-natal women consume the extract of ethnic fermented rice product bhaati jaanr due to high calorie content, to regain the strength (Tamang and Thapa, 2006). In South India, more than 10 varieties of cereal and millet based fermented foods and beverages have been prepared and consumed regularly. Most of the South Indian fermented foods were based on rice and some of the preparations were fortified with legumes, thus forming wholesome combination of carbohydrates and protein. One of the popular south Indian traditional food is Idli a fermented rice based preparation has received much scientific attention. Microflora of idli fermentation has been explored extensively and the household batter preparation has been converted to small scale industry to meet the demand for traditional product by urban population. Recent studies on replacement of rice with other millet such as finger millet were acceptable by consumer’s and flavour was reported to be improved (Teniola and Odunfa, 2001). The process for the production of idli using fermented dehydrated batter was also developed and marketed successfully in South India. Other than these fermented foods south Indian millet based fermented preparations such as Koozh, Fermented rice and Kanjika has received only little scientific attention. These foods have been in use for long time but in recent years consumption and preparation of South Indian traditional foods were confined to rural people which may slowly lead to loss of traditional knowledge. The traditional home scale processes have to be upgraded which will preserve Indian cultural heritage and also improve the livelihood of local families producing these foods. 19 Table 2.3 Some Common Ethnic Fermented Products of Indian Subcontinent Fermented product Substrate Microorganisms in- Reference volved in process Gulgule Wheat Pediococcus sp. Tamang et al., (2012) Jilebi Wheat and curd Lactobacillus sp. Kodo ka Jaanr Millet Pediococcus pentosaceus, Tamang et al., (2012) Thapa and Tamang Lactobacillus sp. (2010) Rice/ Wheat and Bengal Leuconostoc mesen- Aliya and Geervani gram torides, (1981) Dhokla Strepotococcus faecalis Dosa/Idli Rice and black gram Leuconostoc mesenter- Sands and Hankin, oides, (1974), Rama- Streptococcus faecalis, krishnan, (1993) Torulopsis. Pullulans Kanji Rice with vegetables Hansenula anomala Satishkumar et al., (2010) Kishk Wheat Streptococcus theromo- (Economidou and philus, Lactobacillus bul- Steinkraus, 1993) garicus Nan Bhatura Maida/Wheat Wheat + starting material Fermented choru Rice Saccharomyces cerevisiae, Haard et LAB al., (1999). S. cerevisiae, D. hansenii S. fermentati L. plantarum L. acidophilus L. mesenteroides L. lactis Streptococcus faecalis, Sekar and Mariap- Sekar and Mariap- Pediococcus acidilacti, pan (2005) pan (2005) Bacillus sp. and Microbacterium flavum. Koozh/Ambali Finger millet, pearl mil- Pediococcus, Leu- Antony et al., let, sorghum conostoc, heterofermenta- (1996) tive LAB 20 2.4. CONCLUSION The presented informations prove the wide traditional knowledge systems of India. The traditional beverages prepared by Indian folks are much competent in satisfying nutrient and health needs. Also microbiological research showed that the production processes of these fermented foods include diverse microbial groups. The benefits offered by fermentation can be well utilised and altered by understanding the microflora involved in the process. Due to intervention of biotechnology some of the indigenous fermented foods have received good marketability. Identification of predominant microbes of fermentation led to the introduction of starter culture in some fermented preparations which improved the safety and marketability of the indigenous foods. But still many more fermented foods were confined to rural population due to laborious processing techniques. Only very little is known about these foods and their microbial content. It is therefore important to analyse microbiology of these products and technologies for improvement of processing has to studied and documented for future generations. 21
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