Hammer crushers vs disk crushers: the influence of working temperature on the quality and preservation of virgin olive oil

Abstract. An investigation was carried out using a hammer-crusher and a disk-crusher for olive paste preparation to evaluate the effects of different processing temperatures on the quality of the virgin olive oils obtained. The tests performed showed that hammer-crushing produces a more intense fragmentation of the olive pits than the disk-crusher, thus resulting in a more substantial increase in output temperature. Higher temperatures in the crusher during olive processing lead to a shorter preservation of the oils. All the analytical determinations performed also showed that the oils obtained from hammer-crushed pastes presented a greater degradation than those from disk-crushed pastes. These findings were further confirmed by the oven test results.