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The selection of fine flavour cocoa and coffee varieties can lead to attractive niche markets but germplasm need to be analysed for non-volatile compounds and aroma precursors. In the present study, green beans of 202 Theobroma cacao L. accessions (acc.), 64 Coffea arabica L. acc., 35 C. canephora Pierre ex A. Froehner, 7 C. arabusta Capot & Ake Assi and 2 C. canephora × C. congensis A. Froehner hybrids cultivated in Santo, Vanuatu, and harvested at full maturity, were analysed using High Performance Thin Layer Chromatography (HPTLC). In cocoa, 11 compounds were quantified: two alkaloids, two catechins, five proanthocyanidins, and two anthocyanins. Multivariate analyses revealed that Amenolado acc. are differentiated from Criollo, Forastero and Trinitario acc. due to their low caffeine, catechins, and proanthocyanidins contents. Hybrids involving an Amenolado parent also produce low non-volatile compounds contents. In coffee, 11 compounds were quantified: sucrose, two alkaloids, and eight chlorogenic acids. The two major species were differentiated by their mean caffeine content (12.69 mg/g in C. arabica vs. 16.04 mg/g in C. canephora), which is highly correlated with CGA and other chlorogenic acids. Each of the eight chlorogenic acids presented higher values in C. canephora. The ratio sucrose/alkaloids + chlorogenic acids was significantly higher in C. arabica (3.24) than in C. canephora (1.68) which could be an explanation for its comparative sweetness. Coffea arabusta interspecific hybrids presented an intermediate value (2.64). Congusta hybrids were low in sucrose. HPTLC is a cost-efficient technique when applied to germplasm characterization of non-volatile compounds in green cocoa and coffee beans. Chemotype selection appears promising for the development of fine flavor varieties.

The thermogenesis and flowering biology of Colocasia gigantea (Blume) Hook. f. were studied from December 2005 to February 2006 on Espiritu Santo, Vanuatu (South Pacific). Endogenous thermogenesis was measured in two ways: (1) continuously over 5-day periods, and (2) over 3 h during maximum heating. The study showed that heat was generated by the male part of the spadix and probably the lower zone of the sterile region. The temperatures of the male part peaked twice: (1) between 0625 and 0640 (during the female phase) and (2) 24 h later (during the male phase). The average maximum temperature was 42.25 +/- 0.14 degrees C during the female phase (16.63 degrees C above the ambient temperature) and 35.14 +/- 0.22 degrees C during the male phase (10.61 degrees C above the ambient temperature). In the lower zone of the sterile region, thermogenesis was documented only during the female phase. The average maximum temperature was 35.44 +/- 0.41 degrees C (9.82 degrees C above the ambient temperature). Thermogenic heating appeared to be closely associated with the activities of pollinating insects.