Knowledge on physical characteristics of plant and animal food materials are of great importance in its processing, handling, storage, and transportation. These are important to engineers, processors and food scientists, plant and animal breeders, and other scientists. The knowledge on these properties is highly relevant to agricultural and biosystems engineers due to the increasing economic importance of food materials, together with the complexity of modern technology for their production, handling, storage, processing, preservation, value addition and utilization (Adebayo and Nwankwo, 2013).
Size and shape are some of the physical characteristics of agricultural commodities that need to be determined to describe them satisfactorily. These properties are important for the screening, grading, and quality control. They are also important in fluid flow and heat and mass transfer calculations, like drying, dehydration, pneumatic separation, screening, etc. The shape and size of the materials can be determined by graphical methods, dimensional measurement, projected area method, or electronic inspection systems.
The materials that are commonly used in the determination of the overall shape of agricultural commodities are the following: 1) graduated cylinder; 2) beaker; 3) container; 4) caliper; 5) knife; 6) water; 7) ruler; 9) tabulation sheet; 10) pen.
Prior to the conduct of the laboratory activity, samples of different varieties of agro-commodities must be purchased from the nearest local market. During the conduct of the experiment, a specific number of samples for each type of commodity must be selected randomly. The size of the samples can be determined using projected area method wherein three characteristic dimensions will be defined such as (a) major diameter (the longest dimension of the maximum projected area); (b) minor diameter (the shortest dimension of the minimum projected area); and (c) intermediate diameter (the minimum diameter of the maximum projected area or the maximum diameter of the minimum projected area. These dimensions shall be measured using a caliper which is a simple instrument used to measure distances between surfaces.
Meanwhile, the shape of the selected samples can be determined through its longitudinal section, cross-section, and their computed sphericity and the aspect ratio. The sphericity can be calculated using the triaxial formula while the aspect ratio can be calculated using the ratio between the minor radius and the major radius. The formulas that can be used were as follows:
References
Calpe, E. A. (2020). ABE 51-Properties of AB Materials Modules and Lecture Notes.
Engineering Properties of Agricultural Materials. (n.d.). Retrieved October 18, 2020, from Research Gate: https://www.researchgate.net/publication/330533752_Engineering_Properties_of_Agricultural_Materials
