Affiliation :
1. Université Ibn Tofail | Faculté des sciences | Laboratoire de biotechnologie microbienne | Bp133, 14000 | Kenitra | MAROC |
ABSTRACT
Background: Table olives are the most important fermented vegetables because of their worldwide economic importance. The process of natural lactic fermentation of green olives is too long and usually associated
with several types of olive deteriorations. Objectives: The aim of the study was to establish a controlled process for the fermentation of olives. The main purpose was also the selection of a starter culture for industrial
application. Methods: Evaluation of spontaneous fermentation of some plant material at different concentrations of salt provides an interesting starter culture. This paper describes the spontaneous fermentation of olives at
different concentrations of salt and attempts to replace the natural fermentation with fermentation conducted with a very small and suitable inoculum at 10% of salt. A novel starter culture consisting of two strains was
successfully used in green olive fermentations. Both strains were previously isolated and characterized attending to their acid production, among other characteristics. Results: The results of this study showed that the
Controlled fermentation allowed us to reduce the time of fermentation; decline in pH to reach 4.3 was achieved in the first 10 days and 3.5 at the end of the process. Similarly the contents of organic acids increased rapidly
in the first 10 days of fermentation to give values higher than 1.3 at the end of the process. Conclusions: Final pH values and acid development suggested that this selected starter culture may be added to accelerate the
fermentation process and to improve the microbiological control of the process. Fermentations using Candida guilliermondii and Lactobacillus amylovorus for the first time as a starter culture strains allowed us to obtain
stable products for minimally six months.
Keywords : traditional fermentation, microbial inoculum, Controlled fermentation, food safety.