Thanks to Eric, I had a chance to taste some Ghirardelli “Intense Dark“, a 77% dark chocolate bar with no indication as to bean origin. It’s a very smooth bar, with a strong chocolate flavor and predominantly nutty and grassy smell notes. For a 77%, it’s not too acid or astringent, suggesting a high content of probably African Forestero beans. It’s beautifully tempered, with a very high gloss.
The interesting thing about this bar is the very long lingering nutty afternote. With many darker chocolates, I find the afternote to be much fruitier and acid. This afternote is much more bitter and a “lower” note, almost coffee-like. Why might this be? In a word, roasting!
Ghirardelli is unusual among chocolate manufacturers in that they roast the nib (the inner part of the cacao bean) after shelling the bean, as opposed to the more traditional process of roasting the bean in shell, then removing the hull. After the hulls are removed (either before or after roasting), the hulls are discarded and the nibs are ground into chocolate liquor that is then refined with other ingredients into actual chocolate. Some manufacturers have experimented with roasting the liquor, but have found it largely unsatisfactory.
The reason for roasting the nib is that you don’t need to worry about burning the outer hull of the bean, and can hence roast harder without getting off notes. Traditional roasters hypothesize that roasting in the hull may contribute to flavor development, as the hull has presumably taken up some of the flavor notes that existed in the pulp of the cocoa pod. Research into flavor development during the earlier parts of the process (fermenting and drying the beans) indicates that there is significant chemical interplay between the germ, the nib, the hull, and the pulp of the cocoa pod. Some research results for future summarization: protein evolution, and microflora. Given the complexity of the process, there may be hull-to-nib interaction during the roasting process that alters the chocolate’s taste profile.
I don’t know if the lack of hull during the roast process or the ability to roast more aggressively contributes to the flavor of Ghirardelli, but it shows how the roasting parameters can affect the taste of the final product. During the Chocolate Technology course, we got the chance to taste underroasted, mid-roast, and significantly overroasted chocolate. Underroasting leaves a very bitter, acid chocolate, presumably as the result of residual phenols. Overroasted chocolate was full of toasty flavors, and had interesting notes that reminded me of grass and even caraway. Interestingly, the former brewer in the class liked this chocolate, saying that the flavors were reminiscent of very dark beer.
(Ghirardelli, now owned by Lindt, definitely falls in the mega-producer category.)