Effect of the types and concentrations of alkali on the color of cocoa liquor

Abstract

BACKGROUND: The alkalization process is extensively used in the cocoa industry, but information is scarce and not easy to acquire. The goal of the study was to evaluate the effect of different types and concentrations of alkali on the color of cocoa liquor. Dried beans from Chuao (state Aragua, Venezuela) were used to produce cocoa liquors. Samples of liquors were alkalized with solutions of NaHCO 3 , Na 2 CO 3 and NaOH at concentrations of 10, 20 and 30 g kg −1 .

Analysis of Cocoa Proanthocyanidins Using Reversed Phase High-Performance Liquid Chromatography and Electrochemical Detection: Application to Studies on the Effect of Alkaline Processing

“…Lower L values correspond with a darker appearance, whereas lower a and b values correspond with less red and less yellow, respectively (Table 3). 28 These results are important because one of the primary uses of alkalization today is to modify the color of cocoa, which was successfully achieved in this study. 22 …”

State‐of‐the‐Art Chocolate Manufacture: A Review

“…The initial purpose of alkalization was to increase the dispersion properties of the cocoa powder when mixed with milk or a water‐based beverage. However, the alkalization of cocoa beans or liquor is now also done to intensify their color (Figure ), although it also affects the aroma and taste of the cocoa (Rodríguez and others ; González and others ). There are several types of alkali available for this process and the specific compound used and its concentration will influence the color and taste of the final product (Montero ; Beckett ).…”

Institute of Food Technologists (IFT) Education Division Competition 2011 Winner—Cocoa Powders: Are They All Created Equal?

“…Certain attributes of the flavor and mouthfeel of cocoa powder are also related to the cocoa's polyphenol content, particularly the properties of bitterness and astringency (Misnawi and others 2004). Because polyphenols are unstable under neutral and alkaline conditions, a reduction in these sensory properties is noted when the cocoa is processed with alkali (Noor‐Soffalina and others 2009; Rodriguez and others 2009). As would be expected, a reduction in the acidic flavor note also occurs with alkalization (Afoakwa 2010).…”

“…These precursors then react to form larger, brown pigment molecules (Parkin 2008). As the pH increases as a result of the alkalization process, polyphenol oxidase is able to act more effectively, causing light brown cocoa powder to darken and turn a reddish‐brown color (Rodriguez and others 2009). At even higher pHs, the cocoa powder becomes black, taking on the distinctive color of Oreo cookies (Rodriguez and others 2009).…”

“…As the pH increases as a result of the alkalization process, polyphenol oxidase is able to act more effectively, causing light brown cocoa powder to darken and turn a reddish‐brown color (Rodriguez and others 2009). At even higher pHs, the cocoa powder becomes black, taking on the distinctive color of Oreo cookies (Rodriguez and others 2009). Certain attributes of the flavor and mouthfeel of cocoa powder are also related to the cocoa's polyphenol content, particularly the properties of bitterness and astringency (Misnawi and others 2004).…”