Improving Malaysian cocoa quality through the use of dehumidified air under mild drying conditions.
BACKGROUND
Various studies have been conducted in the past to improve the quality of Malaysian cocoa beans. However, the processing methods still remain crude and lack technological advancement. In terms of drying, no previous study has attempted to apply advanced drying technology to improve bean quality. This paper presents the first attempt to improve the quality of cocoa beans through heat pump drying using constant air (28.6 and 40.4 °C) and stepwise (step-up 30.7-43.6-56.9 °C and step-down 54.9-43.9 °C) drying profiles. Comparison was made against hot air drying at 55.9 °C.


RESULTS
Product quality assessment showed significant improvement in the quality of Malaysian cocoa beans. Quality was found to be better in terms of lower acidity (higher pH) and higher degree of browning (cut test) for cocoa beans dried using the step-up profile. All heat pump-dried samples showed flavour quality comparable to that of Ghanaian and better than that of Malaysian and Indonesian commercial samples. Step-up-dried samples showed the best flavour profile with high level of cocoa flavour, low in sourness and not excessive in bitterness and astringency.


CONCLUSIONS
Dried cocoa samples from the step-up drying profile showed the best overall quality as compared with commercial samples from Malaysia, Indonesia and Ghana. The improvement of Malaysian cocoa bean quality is thus achievable through heat pump drying.
Hii
Ching L
CL
Department of Chemical and Environmental Engineering, University of Nottingham, Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor Darul Ehsan, Malaysia.
Law
Chung L
CL
Cloke
Michael
M
Sharif
Suzannah
S
D000388:Air; D002099:Cacao / Q000592:standards; D003890:Desiccation / Q000379:methods*; D005511:Food Handling / Q000379:methods*; D005524:Food Technology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008296:Malaysia; D028321:Plant Preparations / Q000032:analysis* / Q000592:standards; D012639:Seeds; D013649:Taste; D013696:Temperature
D028321:Plant Preparations