Effects of different preservation methods and storage on Spanish‐style domat olives fermented with different chloride salts

Abstract

In this study, Domat olives were fermented with different chloride salts (NaCl, KCl, and CaCl2) then preserved with different preservation methods (pasteurization, potassium sorbate, and ozone treatment). The effects of preservation methods on the main physicochemical and microbiological characteristics related to these table olives were evaluated during the storage period (up to 240 days). The results showed that preservation and storage affect the characteristics of table olives. Preservation methods applied reduced the hardness of the olives, pasteurized olives were found the hardest, and ozone-treated olives were the softest at the end of storage. Preservation techniques have significantly affected the pH of olive brine and statistically found to be different from pasteurized olives, potassium sorbate used, and ozonated olives (p < .05). In particular, the a* values of olives with potassium sorbate changed from the green region (negative values) to the red region (positive values) during storage. The lowest a* value was determined in olives using potassium sorbate and the highest a* value was determined in pasteurized olives. While potassium sorbate was effective in yeast-mold inhibition, it was not effective on lactic acid bacteria (LAB) and total mesophilic aerobic bacteria count (TMAB), and approximately 1 logarithmic unit reduction was observed in LAB and TMAB numbers at the end of storage. Although there was a decrease of approximately 3–4 logarithmic units in the number of yeast-mold at the beginning of the storage (day 0) after the ozonation process, a sudden increase was observed on the 15th day of the storage, and then, it tended to decrease generally by following a fluctuating course. The hardness of olives produced using KCl (3.5% NaCl + 3.5% KCl) decreased significantly after the 6-month storage period that caused a lower acceptability. Practical applications The aim of this article was to find the effects of preservation methods and storage time on some quality parameters of Spanish-style table olives processed with different chloride salts. The findings are guided by the choice of preservation technique and storage time for the table olive industry. The study provides the industry to choose the preservation technique of table olives processed with different salts. Therefore, this paper provides information about Na, K, and Ca contents in the flesh of fermented Domat green table olives as well as their physicochemical characteristics and satisfy consumer demand for low Na with K and Ca fortified table olive.