Diversity of Cacao Trees in Waslala, Nicaragua: Associations between Genotype Spectra, Product Quality and Yield Potential

Abstract

The sensory quality and the contents of quality-determining chemical compounds in unfermented and fermented cocoa from 100 cacao trees (individual genotypes) representing groups of nine genotype spectra (GG), grown at smallholder plantings in the municipality of Waslala, Nicaragua, were evaluated for two successive harvest periods. Cocoa samples were fermented using a technique mimicking recommended on-farm practices. The sensory cocoa quality was assessed by experienced tasters, and seven major chemical taste compounds were quantified by near infrared spectrometry (NIRS). The association of the nine, partially admixed, genotype spectra with the analytical and sensory quality parameters was tested. The individual parameters were analyzed as a function of the factors GG and harvest (including the date of fermentation), individual trees within a single GG were used as replications. In fermented cocoa, significant GG-specific differences were observed for methylxanthines, theobromine-to-caffeine (T/C) ratio, total fat, procyanidin B5 and epicatechin, as well as the sensory attributes global score, astringency, and dry fruit aroma, but differences related to harvest were also apparent. The potential cocoa yield was also highly determined by the individual GG, although there was significant tree-to-tree variation within every single GG. Non-fermented samples showed large harvest-to-harvest variation of their chemical composition, while differences between GG were insignificant. These results suggest that selection by the genetic background, represented here by groups of partially admixed genotype spectra, would be a useful strategy toward enhancing quality and yield of cocoa in Nicaragua. Selection by the GG within the local, genetically segregating populations of seed-propagated cacao, followed by clonal propagation of best-performing individuals of the selected GG could be a viable alternative to traditional propagation of cacao by seed from open pollination. Fast and gentle air-drying of the fermented beans and their permanent dry storage were an efficient and comparatively easy precondition for high cocoa quality.

Tuning Chocolate Flavor through Development of Thermotolerant Saccharomyces cerevisiae Starter Cultures with Increased Acetate Ester Production

“…Specific chocolate flavor notes have been related to cocoa tree variety and growing conditions, postharvest treatments, and the chocolate manufacturing process (4,5). For example, it has been shown that different cocoa tree genotypes influence the flavor of fermented beans and liquor (2,(47)(48)(49)(50). However, modulating chocolate flavor by changing the cocoa cultivar would require elaborate plantation management by planting (a combination of) specific cocoa tree varieties, which in turn might be more disease susceptible or have a lower yield.…”

“…Temperature and pH were measured in real time in the middle of the fermenting mass using a digital pH meter (pH 3310 SET 2, SenTixH 41; WTW GmbH, Weilheim, Germany). Cocoa bean samples (200 g each) from the fermentations were taken after 0 (fresh cocoa beans, right after opening the pods), 4,24,48,72, and 96 h. The bean samples were cooled to 4°C and analyzed within 1 h. Therefore, a 40-g sample was mixed with 160 ml of 0.1% peptone water in an aseptic stomacher bag. The suspension was powerfully shaken and manually kneaded for 5 min, and a 10-fold serial dilution in 0.1% peptone water was made of the homogeneous cocoa pulp solution.…”

Flavor Chemistry of Cocoa and Cocoa Products—An Overview

“…Also, in dried and unfermented beans, the level of (−)‐epicatechin decreases by about 50% (Giacometti and others ). It has also been suggested that the reduction of the polyphenol content during fermentation can be influenced by genetic peculiarities, such as anatomical features of the beans (Trognitz and others ).…”

Chocolate Consumption is Associated with a Lower Risk of Cognitive Decline

“…If the types of certain foods are not specified (i.e., dark chocolate versus milk chocolate), it is possible to over or underestimate true associations with outcomes [25]. In the case of chocolate, there is a wide variety on theobromine concentration among different types of chocolate and the theobromine/caffeine ratio has also been observed to be highly variable, from 1.9 to 10.6 [26]. Because of this limitation, we decided to focus on chocolate intake, data we could access directly from the FFQ.…”