**3. Evaluation of fermented cocoa**

Once the cocoa is fermented, typing analysis is done to classify it. The cut test (**Figure 1**) is to identify cocoa beans that have been well-fermented, lightly fermented, and non-fermented. However, it will allow you to observe the grains that present problems, including; over-fermented, slaty, sprouts, affected by insects.

**Figure 1** schematizes the portion of a cutting test (carried out manually with the help of a knife) of cocoa beans. This test seeks to know the percentage of fermentation that specific cocoa has—the determination to be made in at least five (5) replicas of 100 grains each.

Cocoa is classified commercially according to the percentage of fermentation. In Venezuela, the established classification [51, 52] in Extra Fine (EF: 95%), Fine First (F1: 80%), Fine Second (F2: 20%). It is known as ordinary cocoa beans with fermentation percentages lower than F2.

It is an international consensus that cocoa beans with brown coloration and welldefined streaks on their cotyledons are fully fermented. Grains with violet/brown colorations are associated with slightly fermented grains. Grains purplish, compact, or very little change in the violet color (typical of Trinitarios and Forasteros) may be unfermented. **Figures 2**–**4** show cocoa beans with these characteristics.

In **Figure 2**, cocoa beans with violet coloration are shown, indicating that they are not fermented. In the dissection of these beans, it is observed that there are no well-defined cracks or channels, which are formed due to the microbiological succession and enzymatic reactions that occur during the fermentation process. The bean shown in the upper left part has a dark, blackish coloration, which indicates that it is a slate grain, not desirable in transforming from cocoa to chocolate. The dissection of the lower-left grain shows a violet coloration and compaction in it, indicative of non-fermented grains; it also presents white areas that could indicate the presence of fungi or attack by insects.

**Figure 1.**

*Cutting test of cocoa beans from various cocoa-producing areas of Venezuela, representing fermented, slightly fermented, unfermented, and damaged beans.*

**Figure 2.**

*Unfermented cocoa beans (upper and lower left) and well-fermented cocoa beans (upper and lower right).*

**Figure 3.** *Slate cocoa bean with insect attack.*

The upper-right grain has a brown color and a notable presence of cracks or channels in its cotyledons that indicate that it has completed the fermentation process. Another indication of a well-fermented grain is observed in the lower-right grain, in which, although cracks and channels are not perfectly evident, it presents the separation or opening of its cotyledons, which allows classifying them as well or completely fermented.

Slate cocoa beans (**Figure 3**) generally appear due to a lack of fermentation or incomplete fermentation (which is interrupted by the producer for various reasons). Slate grains are associated with increased bitterness and astringency. Attributes that later affect the cocoa paste (liquor) and, therefore, the production of chocolate.

**Figure 4.** *Slightly or partially fermented cocoa beans.*

This bean also has a compact appearance (not fermented). The bean shown a cavity in the center indicates that insects have attacked it. Generally, this occurs because there are poor storage conditions (relative humidity and temperature). Proliferating species such as *Ephestia elutella*, which in addition to causing damage to the beans, can affect the production of chocolate.

**Figure 4** shows cocoa beans that have passed the fermentation process; however, it has not been complete for them. Obtaining slightly or partially fermented grains occurs because the fermentation mass is excessive; there are no controlled processes for removing the fermentation mass or due to the location of the grains in the drawers or fermentation systems, in addition to the amount of mucilage that each grain has. In this image (**Figure 4**), the dissection of the upper-right grain is an excellent example of partially fermented. The periphery of the grain is purple, and the center of the grain is brown, with the appearance of channels.

Forasteros-type grains, as they present a natural intense violet color, can often pass as unfermented or partially fermented. Therefore, it is necessary to know the evaluation criteria very well to avoid incurring classification errors.

Finally, it is essential to note that the purpose of the cutting test is to establish a commercial classification and does not establish a precise and exact indicator of what the aromatic or flavor quality of the cocoa beans will be.

Another parameter to consider in fermented cocoa is the percentage of acidity because many times high fermentation percentages (greater than 90%) generate a higher content of acetic acid (predominant acid in cocoa due to the action of acetic acid bacteria). The high acidity makes cocoa paste/liquor require long working times in chocolate conching machines. In the case of Venezuela, the relationship between cocoa producer-chocolatier-artisan's increases day by day. With this, criteria can be established regarding the final fermentation percentages that are desired for a specific type of cocoa.
