Pod storage with roasting: A tool to diversifying the flavor profiles of dark chocolates produced from 'bulk' cocoa beans? (Part II: Quality and sensory profiling of chocolates).

The impact of pod storage (PS) and roasting temperature (RT) on the quality parameters and the sensory profiles of dark chocolates were evaluated. Dark chocolates (70%) from ten liquors of different PS and RT combinations as well as six liquors of different origins (Ecuador, Ghana, Ivory Coast, Madagascar, Venezuela and Vietnam) with variable genetic groups were produced under identical conditions and compared. To a greater extent, the range of chocolate quality attributes underscored the generally minimal effects of PS, RT and origin of liquor on the processing conditions. Although with a few exceptions, generally, chocolate acidity (pH and TA) decreased with increasing PS and vice versa in the case of RT. Furthermore, results from a balanced incomplete block design (BIBD) involving a 16-member expert panel also revealed the impact of the applied treatments (PS and RT) on the final flavor profiles of the chocolates irrespective of the origin or genetic groups of the cocoa beans. The same was confirmed when instrumental aroma results were correlated with the sensory data using partial least squares (PLS) regression models. Thus, this study demonstrates the possibility of creating diverse flavor profiles (even towards 'fine' flavor) from 'bulk' cocoa beans through an optimized combination of PS and RT. The findings are therefore expected to challenge the status-quo, especially in the way 'bulk' cocoa is currently processed and consequently priced, thereby, possibly fostering a win-win situation between cocoa producers and industries.

Tuning the aroma profiles of FORASTERO cocoa liquors by varying pod storage and bean roasting temperature.

The unique impact of roasting conditions on the aroma quality of cocoa beans has been demonstrated in many studies. However, information on the additional impact of pod storage (PS) and its combined effect with roasting temperature (RT) is unknown. Hence, this study sought to elucidate the collective contribution of these post-harvest/process parameters on the aroma profiles of cocoa liquors produced from Forastero cocoa beans. The beans had been subjected to different treatments following a 3 × 4 full factorial experiment, consisting of PS (0, 3, 7 days) and RT (100, 120, 140, 160 °C). Statistical analysis of the results from HS-SPME-GC-MS revealed significant (p < .05) impact of both PS and RT as well as their interaction effects on the ten groups of volatiles (acids, alcohols, esters, terpenes, aldehydes, ketones, pyrazines, furans, pyrroles and others) and their overall aroma concentration. An exception was however noted for aldehydes, where the total concentration was only significantly (p < .05) influenced by the individual effects of PS and RT. A subsequent clustering of the liquors, first on the basis of all identified volatiles, then, on the basis of the odor-active volatiles, also revealed similar pattern where liquors with high RT's possessed more volatiles with higher concentrations and vice versa. More so, it seemed that no or very minimal PS treatment was necessary for preserving more aromatic volatiles with typically fruity, floral or spicy flavor notes, whereas, for liquors with volatiles exhibiting more cocoa, chocolate, nutty and roasted flavor notes, prolonged PS (> 3 days) treatment was required. These findings are expected to challenge the status-quo, specifically in the conventional ways through which the aroma potential of 'bulk' cocoa may be steered. On the one hand, the idea of manipulating PS treatment and roasting conditions may indeed consolidate the possibility of creating diverse and/or distinct aroma profiles from the same 'bulk' cocoa beans, whereas, on the other hand, it raises the question whether the Ghanaian cocoa beans - being described as 'bulk' cocoa - could be a consequence of prolonged pod storage treatment.

Pod storage with roasting: A tool to diversifying the flavor profiles of dark chocolates produced from 'bulk' cocoa beans? (part I: aroma profiling of chocolates).

The impact of pod storage (PS) and roasting temperature (RT) on the aroma profiles of dark chocolates were evaluated. Cocoa liquor samples comprised of ten different combinations of PS and RT, whilst keeping the roasting time fixed at 35 min. Additionally, commercial cocoa liquors from renowned origins (Ecuador, Madagascar, Venezuela, Vietnam, Ivory Coast and Ghana) were acquired for comparison. From these, 70% dark chocolates were produced under the same conditions after which they were subjected to headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) analysis. Although both PS and RT were found to influence the aroma volatile concentrations, the impact of RT over PS seemed to be greater. An agglomerative hierarchical clustering (AHC) of all chocolates on the basis of their aroma profiles revealed a similar impact as earlier observed, where major clustering of the chocolates was in accordance with the intensity of the roasting process applied. However, within each group, the dissimilarities owing to PS among the chocolates was clearly depicted. Comparatively, chocolates with low (100-120 °C), instead of moderate to high (135-160 °C) RT's, rather showed a low dissimilarity with those from the commercial cocoa liquors of the different origins. Although from the same beans, the diversity of aroma profiles of these chocolates as well as the similitude of some treatments to some chocolates from commercial grade cocoa liquors, unequivocally underscores the possibility for steering diverse distinct flavors from 'bulk' cocoa through PS and roasting, with beneficial implications, both from an application and an economic point of view.

Assessing the influence of pod storage on sugar and free amino acid profiles and the implications on some Maillard reaction related flavor volatiles in Forastero cocoa beans.

The practice of pod storage (PS) has been applied in many cocoa producing countries, especially by Ghanaian farmers over the years. However, the study of PS has not received much attention, hence, until now, its potential impact on specific flavor precursor development and implications on the flavor of cocoa beans still remains uncovered. The study was therefore aimed at exploring this possibility through physico-chemical and flavor precursor analyses, carried out on equally fermented and dried pod stored (0, 3 and 7 days) Ghanaian cocoa beans. Flavor analysis was also conducted on equally roasted pod stored cocoa beans. Through visual assessment of the pods, pulp and beans, the compelling impact of PS on fermentation index (FI) and nib acidity could be demonstrated by the various biochemical and physical changes such as respiration, moisture reduction, and cellular degradation, occurring during the process. Whereas the entire reaction of sugar degradation may be deemed complex, a clear relationship between the FI, nib acidity and the glucose content was observed. Also, PS was found to increase with marginal increase in total reducing sugars (glucose and fructose). Although the concentration of free amino acids was directly proportional to the duration of PS, within the framework of this study, a significant difference (p < .05) was only observed in the case of extended duration (7 days). Overall, 7 PS seemed to have enhanced the formation of more volatiles. This was followed by 0 PS and finally 3 PS. Suggestively, these findings could provide some indications in explaining the typical flavor profiles of the Ghanaian cocoa beans, considering the fact that 87.8% of Ghanaian farmers adhere to this practice. Meanwhile, for the chocolate industry, the surging demand for cocoa/chocolate products exhibiting unique flavors, could be partly addressed by adopting PS as a tool for varietizing the flavor capacity of "bulk" cocoa through the expression or suppression of specific flavor precursors in the raw material on the farm level, which comes with almost no additional cost.