# Spontaneous and Controlled Fermentation Tests in Industrial Table Olives Production
## 4 Discussion and Conclusions  
Data obtained from salt content determination in barrels N1, N2, G1, and G2 can be explained because aliquots of fresh brine were added to the samples; these had values close to 12%, while the different salt content in FUO barrel can be explained by the fact that the barrel was kept sealed during the whole process until the fifth sampling (June). The increase in salinity at the next sampling (September) was almost certainly due to excessive evaporation of the brine. This is reasonably explained because the barrel was in the middle of the storage yard and so it was fully exposed to the summer sun and its thermal effects. Figure 14: AHC phenolic substances pulp. In fact, after the first sampling and subsequent topping up with fresh brine, the brine level detected on reopening had dramatically decreased. Free total acidity is to be considered acceptable, even if we could not discriminate between the different acidic species, as [PERSON] et al. suggested in their work [21]. The pH values revealed data that are, according to [PERSON] et al., about right for natural fermented olives [22], especially regarding the FUO barrel. Regarding Pearson' correlations, we can observe, as it is logical to expect, the inverse correlation between ash and humidity, given that the increase of the second on the fresh weight will result in a decrease of the ash after calcination. Another logical and confirmed inverse correlation is the one between salt and humidity, since as the salt in the brine increases, there will be an increasing osmotic pressure that will lead to the dehydration of the olives. The correlation between ash and the pulp/seed ratio (P/S), although evident and significant, is not clearly interpreted since, for the determination of the ash, we start from equal weighted quantities of pitted pulp. The same happens for the correlation between salt and P/S ratio; presumably, it can be considered that, in olives with a higher P/S ratio, the salt permeates the tissues more slowly and therefore olives that have a lower P/S ratio have a lower pulp thickness, so they offer less resistance to the passage of salt into the tissues. Likewise, the strong positive correlation between the salt and ash content is also clear, since this is found together with the ash, and the same is for the correlation between the P/S ratio and humidity. On the contrary, the oil content of the various samples, while showing some interesting correlations, does not report values of \(p<0.05\). In our opinion, the strongly positive correlation between this parameter and the salt content (which could be an index of cell lysis) is of interest; it is logical to observe a negative correlation between the oil content and humidity, given the analytical method used. This investigation, conducted in industrial operating conditions, has revealed some aspects of the production of naturally fermented table olives that did not emerge from the consulted bibliography. First, the set of analytical determinations clearly displayed that although the starting situation was the same, the finished products showed slight differences. This may be due to several factors, including population of resident microflora (qualitative and quantitative), competition between starter microorganisms, presence of any bacteriophages [23], climatic conditions, barrel location, and operating conditions. Second, the evolution of the phenolic profile clearly differentiates the fresh product from the finished product, but further characterizes the different finished products, demonstrating that there are different types of debittering depending on the type of microflora that prevails in the brine.