Design and development of a grading machine for the post-harvest handling of mangoes | |
| Author | Chusak Chavapradit |
| Call Number | AIT Diss. no.AE-96-05 |
| Subject(s) | Mango Fruit--Handling |
| Note | A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Dissertation ; no. AE-96-05 |
| Abstract | The introduction of impact rebound response technique for maturity determination of mangoes has opened up new feasibility for the non-destructive quality sorting of fruits and vegetables. The objective of this study was to design and development of a grading machine for Thai mango variety. Study on the possibility of maturity sorting of intact mango using optical property such as color and mechanical properties such as dimensions of produce, flotation, sonic resonance response was investigated. Inadequate potential of maturity sorting of mango based on the optical property and mechanical properties indicated by irregular characteristics of mangoes. The sensitivity of maturity sorting using color was poor as mangoes remain mostly green even at maturity stage. Similarly, the complication in designing of the sorting machine based on specific gravity and three dimensional ratio angles that were just-perceptible maturity grading parameters. The modification of the equipment at the preferred repeatability and sensitivity of the sonic response technique system could not be verified by possibility of the principle and instrumentation. Impact rebound response was achieved from the duplication of hammer's impact and rebound on the sample. Spring was fixed on the hammer and impact was occurred by the return of spring. The hammer rebound, after impact on the sample, by the reaction force from the sample and compressed the spring for the next impact. Impact and rebound actions continuously ensured but in damp order until rest. The velocity, in terms of induced emf, of the hammer induced impact rebound response signal. The characteristic of the signal indicated into different parameters such as damping constant, damping coefficient, maximum and minimum response amplitude, response frequency and response ratio. Damping constant was theoretically and tested to be related with firmness. This impact rebound parameter was decreasing with maturity stages in three varieties of mango, i.e., Nam-dokmai, Kaew-savuoy and Kaew. High correlation (R2 = 0.81) between damping constant and yield test force for three varieties of mango was procured form regression analysis. Elasticity of the sample was indicated by thumb test force was also highly correlated with damping coefficient (R2 = 0.87). Damping coefficient was decreased with maturity stages in the three varieties of manage. Maximum and minimum response amplitude and response ratio of the impact rebound response were tested for correlation with firmness of the mangoes' sample. Regression correlation of higher than 0.875 were obtained from maximum and minimum response amplitude but lower than 0.700 was attained from the response ratio. All of these three parameters were increased with maturity stages in the three varieties of mango. Impact energy of the hammer determined from the study was 23.38* 10 joules, which was no effect on damage the mango fruit in all stages of maturity. From the results, impact rebound response technique conducted non-destructive in determination of mango maturity. The critical value of 22.5 of damping coefficient was selected in maturity sorting of Nam-dokmai variety of mango by the impact rebound response sensor and maturity grading machine. Sorting efficiency of greater than 95% and sorting error of less than 40% were obtained from sensor and grading machine's sorting, respectively. |
| Year | 1996 |
| Corresponding Series Added Entry | Asian Institute of Technology. Dissertation ; no. AE-96-05 |
| Type | Dissertation |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Agricultural and Food Engineering (AE) |
| Chairperson(s) | Athapol Noomhorm; |
| Examination Committee(s) | Ilangantileke, S. G.;Salokhe, V. M.;Nagarur, N. N.; |
| Scholarship Donor(s) | Government of Australia; |
| Degree | Thesis (Ph.D.) - Asian Institute of Technology, 1996 |