Effect of Mechanical Loads on Guava Quality at Handling

Abstract

This study examined the mechanical loads of guava fruits under different loading conditions at different times. The approach will help in predicting the type and magnitude injuries, which will help in minimum losses and assessment of guava quality.It has also a significant influence on handling, sorting, storage and processing. Some physical, chemical and mechanical properties of common Egyptian guava variety (Mamora) relevant to the material handling were analyzed. The following properties were considered: dimensional size, mass, measured and calculated volumes, real density and sugar content. Mechanical tests (puncture and compression) were also considered. The rupture load, rupture deformation and the work done (energy) that caused the rupture of the fruit were determined. The maximum force and stress levels for both puncture and compression were greatest at the start of maturity stage compared with subsequent maturity stages. At any fruit position and as the stage of fruit maturity increases from start to near the final stage, a gradual decrease in the yield force and yield stress was obtained, while, the damaged area and deformation increased.During packing and handling guava and based on the above information it may be recommended, to lay the fruits on the major diameter axis position, so as it experiences less deformation under loads. It was possible to introduce a factor of safety that may be used in determining the number of fruits in a vertical load for packaging guava fruits in containers and transporting them. Based on this concept, the maximum number allowable of fruit rows inside a container should be three rows, so as to avoid bruising during fruits packaging and handling. Packing was the first step to keep the fruit quality and reduce the handling losses. Further investigations should be done to evaluate and test package type, size, and loading height during storage and transportation.