Isolation and Screening of Lactobacillus plantarum Strains from Attieke Fermentation Process for A Starter Culture Development

Abstract

‘‘Attik’’, a steamed granular cassava (Manihot esculenta Crantz) is the major fermented food plant in Cote d’Ivoire. It is a ready-to-eat meal, couscous-like product, with slightly sour taste and whitish color. This food is recently become very popular and is consumed in all sub-Saharan Africa, Europe, USA and in Asia. Fermentation process of this food is carried out naturally by the use of a traditional cassava starter, which is variable from a producer to another, resulting to an inconstant sensorial quality product. To avoid this situation, the aim of this work is to select lactic acid bacteria (LAB) strains for their use as potential microbial starters for attik preparation. In this sense, five homofermentative bacteria isolated from traditional cassava starters used for ‘‘attik’’ preparation were in vitro screened. The results showed that these strains have an acidification rate greater than those reported in literature. On MRS broth, these five isolates caused a rapid drop of pH of MRS broth below pH 4 in less than 12 h (main food safety factor). They also presented alpha-amylase and also b-glucosidase activities necessary for detoxification of cassava dough. They fermented the indigestible sugar raffinose, and were identified as Lactobacillus plantarum based on their sugar fermentation profile by API 50 CHL kit and MALDI-TOF MS (Matrix-assisted laser desorption ionization-time of flight mass spectrometry), respectively. Based on these suitable properties, these five strains would be in a next step tried in Laboratory scale as microbial starters for reliable and reproducible fermentation of cassava dough into attiek.