Ethiopia has a high demand for baker's yeast in the bread and beverage industries. Unfortunately, Ethiopia has no producing plant for baker's yeast and instead relies on costly imports. The objective of this work was to identify the most productive and useful indigenous baker's yeasts isolated from local fermented foods and drinks, honey and Molasses using leavening ability as the major metric. Six of the test isolates produced a maximum cell mass at 30oC, pH of 5.5 and 48 hours of incubation. Isolate AAUTf1 did not produce hydrogen sulfide, while isolates AAUTf5, AAUTj15 and AAUSh17 produced low levels of this chemical, and isolates AAUMl20 and AAUWt21 produced high levels of hydrogen sulfide, neglecting their utility in baking. The leavening performance of isolates AAUTf1 (Candida humilis) and AAUTf5 (Kazachstania bulderi) had the highest dough volume of 131 cm3 and 128 cm3 respectively in 120 min. Isolates AAUSh17 (Saccharomyces cerevisiae) and AAUTj15 (Saccharomyces cerevisiae) raised the dough volume of 127 cm3 and 125 cm3 respectively, at 60 min compared to commercial yeast (117 cm3 in 90 min). The study also revealed that mixed cultures of indigenous yeasts had better leavening capacity than single cultures. The co- inoculated cultures of AAUTf1 + AAUTf5 + AAUTj15, AAUTf5 + AAUTj15, and AAUTf1 + AAUTj15 + AAUSh17 reached 143 cm3 at 90 min, 141 cm3 and 140 cm3 both at 60 min, respectively. Thus, the indigenous isolates are candidates for optimizing utilization of yeast for fast promotion and utilization in the bakery industries.
Dough Fermentation, Indigenous Yeasts, Leavening Activity, Mixed Culture, Single Culture
- 1. Arias, C.R., Burns, J.K., Friedrich, L.M., Goodrich, R.M., Parish, M.E. (2002). Yeast species associated with orange juice: Evaluation of different identification methods. Appl. Env. Microbiol. 68: 1955-1961.
- 2. Ashenafi, M. (2006). The microbiology of Ethiopian foods and beverages: A review. Ethiop J. Biol. Sci. 5: 189-245.
- 3. Aslankoohi, E., Herrera-Malaver, B., Rezaei, M.N., Steensels, J., Courtin, C.M., Verstrepen, K.J. (2016). Non-conventional yeast strains increase the aroma complexity of bread. PloS One 11, e0165126.
- 4. Birch, A.N., Petersen, M.A., Hansen, A.S. (2013). The aroma profile of wheat bread crumb influenced by yeast concentration and fermentation temperature. Food Sci. Technol. 50: 480–488.
- 5. Ceccato-Antonini, S.R., Tosta, C.D., Silva, A.C. (2004). Determination of yeast killer activity in fermenting sugarcane juice using selected ethanolmaking strains. Brazil Arch. Boil. Technol. 47: 17–39.
- 6. Cho, I.H., Peterson, D.G. (2010). Chemistry of bread aroma: a review. Food Sci. Biotechnol. 19: 575–582.
- 7. Clemente-Jimenez, J.M., Mingorance-Cazorla, L., Martinez-Rodriguez, S., Heras-Vazquez, F.J.L., Rodriguez-Vico, F. (2005). Influence of sequential yeast mixtures on wine fermentation. Int. J. Food Microbiol. 98: 301–308.
- 8. Crafack, M., Mikkelsen, M.B., Saerens, S., Knudsen, M., Blennow, A., Lowor, S. (2013). Influencing cocoa flavour using Pichia kluyveri and Kluyveromyces marxianus in a defined mixed starter culture for cocoa fermentation. Int. J. Food Microbiol. 167: 103–116.
- 9. Domizio, P., Romani, C., Lencioni, L., Comitini, F., Gobbi, M., Mannazzu, I. (2011). Outlining a future for non-Saccharomyces yeasts: Selection of putative spoilage wine strains to be used in association with Saccharomyces cerevisiae for grape juice fermentation. Int. J. Food Microbiol. 147: 170–80.
- 10. Donalies, U.E., Nguyen, H.T.T., Stahl, U., Nevoigt, E. (2008). Improvement of Saccharomyces yeast strains used in brewing, wine making and baking. Adv. Biochem. Eng. Biotechnol. 111:67–98.
- 11. Edwards, W.P. (2007). The Science of Bakery Products. Royal Society of Chemistry, Cambridge.
- 12. Fellers, C.R., Shostrom, O.E., Clark, E.D. (1924). Hydrogen sulfide determination in bacterial cultures and in certain canned foods. J. bacterial. 9: 235–249.
- 13. Godfray, H.C.J., Beddington, J.R., Crute, I.R., Haddad, L., Lawrence, D., Muir, J.F. (2010). Food security: the challenge of feeding 9 billion people. Sci. 327: 812-818.
- 14. Hamelman, J. (2004). Bread: A Baker's Book of Techniques and Recipes. John Wiley, New York.
- 15. Jiranek, V., Langridge, P., Henschke, P.A. (1995). Validation of bismuth containing indicator media for predicting H2S producing potential of Saccharomyces cerevisiae wine yeast under enological conditions. Am. J. Enol. Vitic. 46: 269-273.
- 16. Ma’aruf, A.G., Noroul, A.Z., Sakilah, A.M., Mohd, K.A. (2011). Leavening ability of yeast isolated from different local fruits in bakery product. Sains Malaysiana 40: 1413–1419.
- 17. Mamun-Or-Rashid, A.N., Dash, B.K., Chowdhury, M.N., Waheed, M.F., Pramanik, M.K. (2013). Exploration of potential baker’s yeast from sugarcane juice: optimization and evaluation. Pak.J. Biol. Sci. 16: 617-623.
- 18. Milkessa, T., Abate, D. (2014). Evaluation of Yeast Biomass Production using Molasses and Supplements. LAP LAMBERT Academic Publishing, Germany.
- 19. Moreira, N., Mendes, F., de Pinho, R.G., Hogg, T, Vasconcelos, I. (2008). Heavy sulphur compounds, higher alcohols and esters production profile of Hanseniaspora uvarum and Hanseniaspora guilliermondii grown as pure and mixed cultures in grape must. Int. J. Food Microbiol. 124: 231–8.
- 20. Nitayavardhana, S., Shrestha, P., Rasmussen, M.L., Lamsal, B.P., van Leeuwen, J.H., Khanal, S.K. (2010). Ultrasound improved ethanol fermentation from cassava chips in cassava-based ethanol plants. Bioresource technol. 101: 2741-2747.
- 21. Noroul, A., Ma’aruf, Z., Sahilah, A.G., Mohd, A.M., Khan, A., Wan Aida, W.M. (2013). A new source of Saccharomyces cerevisiae as a leavening agent in bread making. Int. Food Res. J. 20: 967-973.
- 22. Plessas, S., Pherson, L., Bekatorou, A., Nigam, P., Koutinas, A.A. (2005). Bread making using kefir grains as baker’s yeast. Food chemis. 93:585-589.
- 23. Qureshi, S.K., Masud, T., Sammi, S. (2007). Isolation and taxonomic characterization of yeast strains on the basis of maltose utilization capacity for bread making. Int. J. Agri. Biol. 9: 110-113.
- 24. Saerens, S.M., Swiegers, H., Reynolds, D. (2013). Increasing the sensorial enrichment of white wine with non-Saccharomyces yeast strains. Australian and New Zealand Grapegrower and Winemaker, (599), p.94.
- 25. Savova, I., Nikolova, M. (2002). Isolation and taxonomic study of yeast strains from bulgarian dairy products. J. Cul. Collec. 3: 59–65.
- 26. Steensels, J., Snoek, T., Meersman, E., Nicolino, M.P., Voordeckers, K., Verstrepen, K.J. (2014). Improving industrial yeast strains: exploiting natural and artificial diversity. FEMS Microbiol. Rev. 38: 947–995.
- 27. Supanwong, K., Kazuyoshi, O., Shinsaku, H. (1983). Environmental effects on ethanol tolerance of Zymomonas mobilis. J. Microbial. Utilization Renewable Resour., 3: 254-260.
- 28. Team R.C., (2016). R: A Language and Environment for Statistical Computing. R Foundation for statistical Computing, Vienna, Austria. URL https://www.R-project.org/.
- 29. Wedral, D., Shewfelt, R., Frank, J. (2010). The challenge of Brettanomyces in wine. LWT Food Sci. and Technol., 43(): 1474–1479.
- 30. Zaky, A.S., Nasr, N.F. (2011). Easy and efficient method for measuring the rising power of baker’s yeast. International Food Congress-Novel Approaches in Food Industry, pp 650- 654.
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