Chloride salt mixtures affect Gordal cv. green Spanish-style table olive fermentation

Abstract

This work studies the effects of different sodium (in the range of 4–10%), potassium (0–4%) and calcium (0–6%) chloride salt mixtures on the fermentation profile of Gordal olives processed according to the Spanish style. For this purpose, response surface methodology based on a simplex centroid mixture design with constrain (sum of salt percentages = 10%) was used. All treatments reached appropriate titratable acidity levels, but this parameter could not be related to the initial chloride salt concentration. The presence of CaCl2 led to lower initial and after-fermentation pHs, delayed sugar diffusion into the brine, its maximum concentration and titratable acidity formation. CaCl2 also delayed Enterobacteriaceae and yeast sprang, decreasing their overall growth. This chloride salt also showed a tendency to reduce overall lactic acid bacteria growth. KCl had a similar behaviour to NaCl but, in general, increased overall microbial growth. Thus, a partial substitution of NaCl in Spanish-style green olives with KCl and CaCl2 does not substantially modify the fermentation profile but does produce some changes, which, when properly managed, could help to improve product processing.