Evolution of fermenting microbiota in tarhana produced under controlled technological conditions

Abstract

a b s t r a c tThe purpose of this study was to evaluate the evolution of lactic acid bacteria (LAB) and yeasts during the fermentation of tarhana produced with some pasteurised ingredients and carried out at 30 and 40 C. The chemical parameters were those typical for tarhana production. Coliform bacteria were not detected during fermentation, while LAB and yeasts were in the range 10 7 e108 colony forming units (CFU) g À1. Plate counts showed an optimal development of both fermenting microbial groups and the differences in cell concentrations were not significant (P > 0.05). LAB were isolated during fermentation and grouped on the basis of phenotypic and polymorphic characteristics. LAB isolates were identified by a combined genetic approach consisting of 16S/23S rRNA intergenic spacer region (ITS) and partial 16S rRNA gene sequencing as Pediococcus acidilactici, Lactobacillus plantarum and Lactobacillus brevis. Hence, the pasteurisation of the vegetable ingredients, excluded wheat flour, enhanced the hygienic conditions of tarhana without influencing the normal evolution of LAB. However, the fermentation at 40 C favoured pediococci, while the production at 30 C was mainly characterised by lactobacilli. Yeasts, identified by the restriction fragment length polymorphism (RFLP) of the 5.8S ITS rRNA gene, were mainly represented by the species Saccharomyces cerevisiae in both productions.Crown

Effect of using kefir in the formulation of traditional Tarhana

“…Acidity and pH change in this study were in agreement with the observations of previous works (Ekinci, 2005;Erbaş et al, 2006;Obanoglu et al, 1995;Settanni et al, 2011).…”

“…The final rod LAB of dough C and B were similar and higher than in standard tarhana (A). Erbaş et al (2005), Settanni et al (2011) andObanoglu et al (1999b) reported that LAB counts increased in the first days of fermentation and then decreased. They did never detected coliforms during the whole process.…”

Traditional Turkish Fermented Cereal Based Products: Tarhana, Boza and Chickpea Bread

“…cremoris, Leu. mesenteroides subsp. mesenteroides, S. thermophilus, P. pentosaceus and P. acidilactici (Daglioglu, 2000;Erten and Tanguler, 2010;Settanni et al, 2011), and yeast (Rhodotorula glutinis) have also isolated in tarhana fermentation. The most important microbial group for tarhana fermentation is LAB, they have a key role in generation of the aromatic compounds, and moreover they strongly have contributed to the stability of the product during storage by the inhibition of several unwanted microorganisms.…”

“…The most important microbial group for tarhana fermentation is LAB, they have a key role in generation of the aromatic compounds, and moreover they strongly have contributed to the stability of the product during storage by the inhibition of several unwanted microorganisms. Meanwhile, yeasts have further effects on the aromatic profile of tarhana (Settanni et al, 2011). At the end of the fermentation, dough has an acidic and sour taste and is called 'wet tarhana'.…”

“…In contrast; some are minor products in global terms, although they are made commercially in some countries. Examples of these are shalgam , tarhana (Settanni et al, 2011), kefir (Kesmen and Kacmaz, 2011), koumiss (Kabak and Dobson, 2011), ayran, which is a yoghurt based drink, kanji (Erten et al, 2008) and boza (Yegin and Fernández-Lahore, 2012).…”