Study to determine the roll's diameter required to achieve accurate mechanical cracking of table olive fruits.

摘要

The relationship between the fruit and roll diameters suitable to achieve accurate mechanical cracking of table olive fruits was studied. The use of local cracking devices, causes high loss percentage of fruit juice and flesh. Laboratory experiments were conducted on 4 different fruit sizes using 4 modified cracking devices. The time for cracking of a 2 kg fruit probe was determined and utilized for comparison among the different devices. The time for cracking probes by means of 2 rolls, rotating at a peripheral speed of 1.4 m/sec and having diameters equal to 5.24 and 10.95 times the fruit diameter, was 18.38 and 6.4 seconds, respectively. A theoretical analysis on the fruit condition as it falls between the 2 cracking rolls was also conducted to derive equations showing the relationship between fruit and roll diameters and their effect on the force that affects the fruit during cracking operation. The accurate cracking of table olives can be achieved by using rolls having diameters not less than 16-17 times the fruit diameter indicating that the technical specifications of the most locally used cracking devices are not suitable for cracking of table olive fruits.