Effect of temperature on the formation of acrylamide in cocoa beans during drying treatment: An experimental and computational study

Abstract

A B S T R A C TThe aim of this work was to determine the effect of temperature on the formation of acrylamide in cocoa beans during drying treatment by an experimental and computational study, in order to assess the presence of this neoformed compound from postharvest stage. The computational study was conducted on the reaction between fructose, glyoxal from glucose, and on asparagine at the M06-2X/6-31þG(d,p) level, under cocoa bean drying conditions at 323.15 to 343.15 K. The proposed reaction for acrylamide formation consisted of seven steps, which required to progress a via cyclic transition state of the four members. In addition, step III (decarboxylation) was considered to be the rate-determining step. Glucose followed an E1-like elimination and fructose exhibited an E1cb-like elimination. Computational model showed that the reaction of acrylamide formation was favored by fructose rather than glucose.The content of reducing sugars, asparagine and acrylamide in fermented and dried cocoa from two subregions of Antioquia-Colombia, as well as roasted cocoa, were evaluated by UHPLC-C-CAD and UHPLC-QqQ. The concentrations of monosaccharides measured at the end of the fermentation and drying process of cocoa nibs showed greater decreases in the levels of fructose as compared to glucose, supporting the main model hypothesis. Acrylamide formation only occurred in Bajo Cauca due to the presence of both precursors and fast drying time (72 h). Finally, it was possible to find the conditions to which acrylamide can be formed from the drying process and not only from roasting, information that can be used for future control strategies.

Fluidized-Bed-Roasted Cocoa Has Different Chemical Characteristics than Conventionally Roasted Cocoa

“…Acrylamide was detected in unroasted cocoa nibs (Table 1). This compound is produced during the fermentation 47 and drying processes 48 of cocoa in the field. In addition, the limited thermal load involved during the deshelling process may have contributed.…”

Quality Formation of Adzuki Bean Baked: From Acrylamide to Volatiles under Microwave Heating and Drum Roasting

“…y DT = e 0.07(T−91.62) , R 2 = 0.9796, SEE = 4.36 (12) where y DM is the acrylamide content in drum-roasted beans, considering moisture content (M, %), and y DT is the acrylamide content in drum-roasted beans, considering temperature (T, • C). According to Equation ( 8), the critical temperature causing acrylamide content to rise in adzuki beans during drum roasting is 91.62 • C at a corresponding moisture content of 6.1% (w.b.).…”

“…Radio-frequency (RF) heating following convection heating contributes to the occurrence of excessive browning in the internal portion of baked thin biscuits with less acrylamide formation [10]. Besides temperature and components [11], the heating method, such as microwave baking or drum roasting, also dominates the formation of acrylamide in the baked material [12]. The acrylamide content of cookies processed by vacuum baking was 30% lower than in those baked the conventional way due to the low temperature in the vacuum conditions [13].…”

Roasted Rye as a Coffee Substitute: Methods for Reducing Acrylamide

“…The concentration of acrylamide in processed food is strongly dependent on the processing temperature and the composition of raw materials. Food sources rich in proteins and carbohydrates proved to be particularly prone to acrylamide formation, and high amounts of acrylamide were detected in potato chips, French fries [6], bread, coffee [7,8], and cocoa [9,10]. Thus, evaluation of carbohydrate and protein contents (especially that of asparagine) prior and after food processing steps seems to be of importance to determine the relation between the raw materials and final acrylamide content.…”