Clapperton, J., Yow, S., Chan, J., Lim, D., Lockwood, R., Romanczyk, L. & Hammerstone, J. 1994
The contribution of genotype to cocoa (Theobroma cacao L.) flavour. Tropical Agriculture (Trinidad) 71(4): pp. 303-308.
Notes
Malaysia - Sabah Datafile: FLAV__DS -Flavour assessment of genotypes Descriptors: Assessment of flavour attributes, especially cocoa flavour intensity, acidity, sourness, bitterness and astringency. Bitterness and astringency are tested against presence of caffeine and polyphenols. Affects on flavour of prolonged storage of the beans is also assessed. Materials and Methods. Six genotypes (AML, IMC 67, NA 33, PA 7, SCA 12, UIT 1) were selected for preliminary flavour trials due to their widespread use in cocoa breeding in Malaysia and elsewhere. Fermentation and Drying. Experiment 1: ripe pods were harvested on one day and stored for 5 days before breaking. 50kg wet beans were fermented on trays covered with banana leaves, for 120h with a single turn after 48h. Beans were then dried in the sun (supplemented by an indirect heat source during wet weather). Positions were rotated to ensure even drying for each genotype. The procedure was replicated four times between October and December 1989. Experiment 2: UIT 1 alone was used to test the effects of 10 and 15 days pod storage, each receiving 72 and 120h fermentation. Trials were replicated 3 times over six weeks under the conditions described for experiment 1. Cocoa liquors and chocolates were prepared in the UK according to the recommendations of the BCCCA (1980). Taste Testing. Each liquor (4 replicates of six genotypes, including a hidden West African reference) were tasted 3 times. Tasting was carried out by an independent assessor according to an incomplete block experimental test design, and by trained panellists from various chocolate manufacturers using their own taste procedures for liquors and chocolates. Liquors from experiment 2 were tasted by the independent assessor according to an incomplete block experimental test design in which each liquor was tasted 4 times. Data was analysed using analysis of variance on each flavour attribute. Constituent testing. Cocoa butter contents were estimated using soxhlet extraction (International Office of Cocoa, Chocolate and Sugar Confectionary, 1972) Alkaloids caffeine and theobromine analysed using high pressure liquid chromatography (HPLC) and a diode ray detector at 280nm. Flavanols catechin and epicatechin were separated and estimated using HPLC and fluorescence detection. Procyanins were analysed using 2-dimensional chromatography. Character Data: Liquor flavour; cocoa, astringency, acidity: scored on a scale of 1-15 (15=high intensity). Plain chocolate; chocolate, sweetness, acidity, bitterness, astringency, metal, brown fruit, tobacco, mouldy, musty, earthy, baggy: scored on a scale of 1-15 (15=high intensity).
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