New trends on the alkaline treatment 'cocido' of Spanish or Sevillian Style green table olives

The “cocido”: alkaline treatment to eliminate bitterness is the main step involved in the process of elaboration of pickled green olives. Over time, this treatment has undergone a series of modifications in order to reduce the volume of its waste water and to avoid the storage of the fruits, prior to the lye treatment, in the Manzanilla variety. In this paper, a series of previous treatments related to the lye treatment and the principal modifications applied by the industry are optimized. As a previous treatment, related to the mechanical harvesting of the olives, the transport of the fruits freshly harvested in liquid (alkaline solutions of very low concentration) was studied. Also, the addition of calcium and / or sodium salts and a cooling of the lye was studied, with the additional aim of eliminating the storage step in the Manzanilla variety. On the basis of these results, it can be said that a previous storage of fruits of the Manzanilla variety in NaOH solution of low concentration is useful for the mechanical harvesting of olives without a loss in product quality. On the other hand, the addition of calcium and / or sodium salts in the lye solution and the cooling of it improved olive texture and avoided the blistering defect.