| Author | Wahyudi, Teguh |
| Call Number | AIT Thesis no. AE-90-14 |
| Subject(s) | Cocoa
|
| Note | A thesis submitted in partial fulfillment of the requirements for
the degree of Master of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Abstract | 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 • 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 . |
| Year | 1990 |
| Type | Thesis |
| School | School of Environment, Resources, and Development |
| 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) | Illangantileke, Sarath G.
; |
| Examination Committee(s) | Jindal, Vinod Kumar ;Jindal ;Athapol Noomhorm ; |
| Scholarship Donor(s) | NAR II Project of the Government of Indonesia; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1990 |