03716cas a2200409 a 4500 20260818090559.0 111005s1990 th uu|m rtt 0| a1eng d .b10197114 AIT Thesis no. AE-90-14 Wahyudi, Teguh Development and testing of instruments and a process for color measurement as methods to determine cocoa bean quality Bangkok : Asian Institute of Technology, 1990 82 p. Thesis ; no. AE-90-14 A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Environment, Resources and Development Thesis (M.Eng.) - Asian Institute of Technology, 1990 A study to assess the change in cocoa bean quality parameters was made. The study included the testing of existing quality assessment methods, the testing of appropriateness in the use of fermentation index and colo1 measurement as an indirect quality assessment. The possibility of using a simple photodiode sensing instrument as a cocoa color difference meter was also studied. The fermentation index value increased from 0 .47 to 1. 10 for different fermentation durations. Cocoa bean acidity (pH) decreased from 6 . 46 to 4. 82. Reducing sugars increased from 0.27 to 1.01 %, while free amino acids increased from 0.27 to 0 {u2022} 6 7 % for the same fermentation durations . Anthocyanin content decreased from about 50.6 to 15.3 %, yellow/brown pigment polymers increased from about 23. 2 to 53. 8 % , and no significant changes for red pigment polymer, within the changes of cocoa color categories 1 to 5. The test of quality assessment methods showed that the cut- test score and taste- test methods were not adequate lo assess bean quality objectively. The fermentation index method 1.i as useful to distinguish different bean samples from 5 color· categories. The fermentation index related well with other quality parameters, such as pH, reducing sugars , free ami110 acids , a nd cocoa color pigments. Direct color measurement method (in terms of L, a, and b color indicator values) had Q good relationship with fermentation index, pH , reducing sugars, and free amino acids. Color measurement was appropriate to estimate cocoa bean quality. Cocoa color measurements using the developed color measuring instrument were found to be acceptable since tJ1e results h ad a good relationship with fermentation index . Cocoa Illangantileke, Sarath G., Chairperson Jindal, Vinod Kumar, Examination Committee Athapol Noomhorm, Examination Committee NAR II Project of the Government of Indonesia, Scholarship Donor Asian Institute of Technology. Thesis ; no. AE-90-14 Full-Text http://203.159.5.9/ait-thesis/detail.php?q=B18230 .b10197114 mnait s 240329 2 951012 m a s 0 mnait mnait mnarc 20 40 Barcode : 30050003005195 CREATED : 1994-05-16 RECORD # : i10236466 LPATRON : 0 LCHKIN : - # RENEWALS : 0 # OVERDUE : 0 IUSE3 : 0 TOT CHKOUT : 0 TOT RENEW : 0 Barcode : 30050003005229 CREATED : 1994-05-16 RECORD # : i10236478 LPATRON : 1015458 LCHKIN : 2002-11-18 # RENEWALS : 0 # OVERDUE : 0 IUSE3 : 0 TOT CHKOUT : 3 TOT RENEW : 4 Barcode : 30050120363428 CREATED : 2016-05-27 RECORD # : i12999003 LPATRON : 0 LCHKIN : - # RENEWALS : 0 # OVERDUE : 0 IUSE3 : 0 TOT CHKOUT : 0 TOT RENEW : 0 28534 28534 0 0 0 0 MAIN MAIN mnait 2026-08-18 0 AIT Thesis no. AE-90-14 30050003005195 2026-08-18 09:05:59 1 2026-08-18 20 0 0 0 0 MAIN MAIN mnait 2026-08-18 0 AIT Thesis no. AE-90-14 30050003005229 2026-08-18 09:05:59 2 2026-08-18 20 0 0 0 0 MAIN MAIN mnarc 2026-08-18 0 AIT Thesis no. AE-90-14 30050120363428 2026-08-18 09:05:59 2026-08-18 40