Microbial population present in fermented beverage ‘cauim’ produced by Brazilian Amerindians

https://doi.org/10.1016/j.ijfoodmicro.2007.06.020Get rights and content

Abstract

The Tapirapé Amerindians of the Tapi'itãwa tribe produce several fermented foods and beverages among them the beverage called ‘cauim’. This beverage is the main staple food for infants until two years old and their parents. For producing the beverage, several substrates are used, such as: cassava, rice, corn, maize and peanuts. The fermentation using mainly cassava was accomplished and samples were collected for chemical and microbiological analysis. A progressive acidification during the fermentation was observed and pH value decreased from 5.5 to 3.4. Lactic acid was the most important fermentation metabolite found but significant amounts of ethanol and acetic acid were also observed. The microbial load was high at the beginning of the fermentation, bacterial population was about 6.8 log cfu/ml and yeast population was 3.7 log cfu/ml. A total of 355 bacteria were isolated and identified. All the isolates were grouped into Gram-negative (3.5%), Gram-positive non-sporulating (78%) and Gram-positive sporulating bacteria (18.5%). Lactic acid bacteria increased from the beginning of fermentation and became the dominant microorganism throughout the fermentation. Species of bacteria were varied and they were found to be Lactobacillus pentosus, L. plantarum, Corynebacterium xerosis, C. amylocolatum, C. vitarumen, Bacillus cereus, B. licheniformis, B. pumilus, B. circulans and Paenibacillus macerans. The species L. pentosus and L. plantarum were the dominant bacteria and were present in all the periods of evaluation of the samples.

Introduction

Cassava, Manihot esculenta, Crantz is an enlarged root indigenous to Northern Amazon, South America and is widely cultivated in tropical countries. Cassava tubers are mainly used for human nutrition as fermented products and therefore are a staple food and the most subsistence crop in the world tropics. Cassava fermentation processes are adequate for reduction of its toxic cyanogenic glucosides, for preservation and improving product flavour and aroma (Holzapfel, 1997). Indigenous knowledge of ethnic people living in the North and Eastern regions of Brazil on production of fermented food is worthy of documentation. Several Brazilian tribes (Araweté, Kayapó, Karajá, Javaé and Tapirapé) utilize small-scale fermentation for root preservation and for elaboration of cassava fermented dishes and foods (Wagley, 1988). Some tribes use fermentative processes to produce fermented food and beverages with nutritional value, as stimulant and for medical and mythical purposes (Wagley, 1988).

Making these fermented products is based upon old empirical knowledge, which is transferred from generation to generation (Melatti, 1983). The Tapirapé Indians make non-alcoholic beverages, which are fermented initiating from other than cassava substrates, by different techniques and processes, resulting in a beverage named ‘cauim’ (kawí) (Baldus, 1970). To prepare ‘cauim’ beverage cassava roots are allowed to ferment for three to five days in running water to soften the skin. After this time the cassava tubers are peeled, cut in small pieces and sun dried. The dried pieces are then grated into flour. This flour mixed with water is cooked for about 2 h and then cooled at room temperature. When the porridge is cold an inoculum is added to initiate the fermentative process, which usually takes 24 to 48 h. The inoculum is obtained from a fluid resulting from chewing sweet potato by female Indians. Usually ‘cauim’ is consumed in daily meals by Tapirapé Indians by adults and children, particularly it is the main food for infants under two years.

Unfortunately there are no previous studies on the microbiota involved on ‘cauim’ fermentation. However, many different bacteria species have been isolated from several fermented cassava products. Cassava is an important substrate for many fermented foods that are widely consumed in Brazil, Asia and Africa. Lactic acid bacteria are often reported to be involved with cassava and cereals fermentations (Nout and Sarkar, 1999). Leuconostoc mesenteroides subsp. mesenteroides was the dominant strain isolated in attiéké product (Coulin et al., 2006). Lactobacillus plantarum, L. fermentum, L. pentosus, and L. mesenteroides have been reported as the main bacteria isolated from agbelima and fufu (Amoa-Awua et al., 2005, Fagbemi and Ijah, 2006, Amoa-Awua et al., 1996). Bacillus species have been reported in cassava fermentation and according to Amoa-Awua and Jakobsen (1995) Bacillus subtilis was the dominant specie and could be responsible for the textural breakdown of cassava tissue during agbelima production.

There is no published information on the microbiology of the fermented food and beverage produced by Brazilian Ameridians, therefore the aim of this study was to characterize and identify the bacteria populations present in cauim made from cassava.

Section snippets

Fermented beverage

The cauim was prepared by the local Amerindian Tapirapé-Tapi'itãwa tribe, situated next to the Urubu Branco (Mato Grosso, Brazil) mountain located 10.8° S and 51.3° W in the extreme north of Mato Grosso State. For cauim preparation cassava tubers were left in running water for three to four days to soften the skin. After retting the cassava tubers were peeled, sun dried, grated and ground. To start the preparation of the beverage, 2 kg of cassava flour and 1 kg of rice were added to

Identification of bacteria

The evolution of the microbial groups was examined throughout fermentation of cassava to produce cauim. Count of microbial population on different culture media from cassava fermentation is shown in Fig. 1. The total count varied from 5.8 to 10.2 log cfu/ml. Although the microbial load varied by 3.4 orders of magnitude, the proportions of the microbial types showed considerable consistency. Analysis revealed that bacteria were always most abundant than yeasts (Fig. 1). The trend for the total

Acknowledgements

Conselho Nacional de Desenvolvimento Científico e Tecnológico of Brasil (CNPQ) and Fundação de Amparo a Pesquisa do Estado de Minas Gerais (FAPEMIG) are acknowledged for financial support and for MSc scholarship for E.G. Almeida.

References (35)

  • A.A.I. Sanni et al.

    New efficient amylase-producing strains of Lactobacillus plantarum and L. fermentum isolated from different Nigerian traditional fermented foods

    International Journal of Food Microbiology

    (2002)
  • C.F. Silva et al.

    Microbial diversity during maturation and natural processing of coffee cherries of Coffea arabica in Brazil

    International Journal of Food Microbiology

    (2000)
  • N. Thapa et al.

    Phenotypic identification and technological properties of lactic acid bacteria isolated from traditionally processed fish products of the Eastern Himalayas

    International Journal of Food Microbiology

    (2006)
  • K. Adinarayana et al.

    Response surface optimization of the critical medium components for the production of alkaline protease by a newly isolated Bacillus sp

    Journal of Pharmacy & Pharmaceutical Sciences

    (2002)
  • W.K.A. Amoa-Awua et al.

    The role of Bacillus species in the fermentation of cassava

    Journal of Applied Bacteriology

    (1995)
  • W.K.A. Amoa-Awua et al.

    Utilization of unfermented cassava flour for the production of an indigenous African fermented food, agbelima

    World Journal of Microbiology and Biotechnology

    (2005)
  • F. Ampe et al.

    Polyphasic study of the spatial distribution of microorganisms in mexican pozol, a fermented maize dough, demonstrates the need for cultivation-independent methods to investigate traditional fermentations

    Applied and Environmental Microbiology

    (1999)
  • Cited by (70)

    • South American fermented legume, pulse, and oil seeds-based products

      2023, Indigenous Fermented Foods for the Tropics
    • South American fermented cereal-based products

      2023, Indigenous Fermented Foods for the Tropics
    • Functional and nutritious beverages produced by lactic acid bacteria

      2019, Nutrients in Beverages: Volume 12: The Science of Beverages
    • Functional beverages from cereals

      2019, Functional and Medicinal Beverages: Volume 11: The Science of Beverages
    View all citing articles on Scopus
    View full text