Physicochemical and microbiological profile of packed table olives

Abstract

The water activity of different commercial products of table olives as well as their physicochemical and microbiological profiles were studied. Average values of water activity were 0.976, 0.977, and 0.990 for green, directly brined, and ripe (by alkaline oxidation) olives, respectively. Mean values of pH were 3.69, 3.92, and 6.52 while salt levels were 5.53, 4.98, and 2.55 for the same commercial products. In some of the commercial products of green and directly brined olives that were examined, a certain level of microorganisms was observed. Most of them were lactic acid bacteria and yeasts, the lactic acid bacteria being more abundant than the yeasts. Traditionally, this flora has not been considered harmful due to its resemblance to that found in natural and spontaneous fermentation. Spore-forming mesophilic aerobes, which can be considered contaminants from ingredient or product handling, were present in only some samples and were always at low levels. However, their detection does not cause any concern regarding safety because there is no reference showing that they can grow in any of the products studied given the physicochemical characteristics found.