For the level of contamination evaluated and under the conditions used in this study, 93.6% of the ochratoxin A was reduced during the chocolate making process. Considering the results of ochratoxin A in the fractions after roasting and their percentage in the bean composition (Table 3), it is possible to estimate that about 16.6% of the toxin is destroyed by the thermal treatment at 150 °C applied for Kinase Inhibitor Library 40 min, which results in a temperature of about 90 °C in the beans (Fig. 1). This experiment demonstrated that after the roasting

processing, 82.9% of the remaining ochratoxin A stayed in the shell fraction, which is mostly removed from the processing line by winnowing (where a maximum of 1–1.5% of shell residues in the nibs is allowed (Minifie, 1999). Thus, among the steps of cocoa processing, the shelling step is the main one responsible for the decrease of ochratoxin A. The amount of toxin physically removed is greater than that destroyed by the heating treatment of cocoa beans, so the winnowing efficiency can be

considered critical for reducing the ochratoxin A contamination in chocolate and finished products. In the next Selleckchem A 1210477 step, the cocoa mass was obtained after the grinding of nibs and a heat treatment of 70 °C for 3 h. After this step the total reduction increased to 89.9%, showing that this step is also important for ochratoxin decrease. The total reduction achieved in the final product, the chocolate was 93.6%. It has been shown next that the ochratoxin A molecule resists the majority of heat

treatments used for food production (MAFF (Ministry of Agriculture & Food), 1996). A study conducted by Boudra, Le Bars, and Le Bars (1995) in dry wheat under temperatures and time of exposure similar to those applied in our study demonstrated that the ochratoxin A reduction achieved was 20%, similar to the values found in our study (16.6%). Manda et al. (2009) evaluated the stability of ochratoxin A during the cocoa processing, finding decreases between 23.7% and 40.5% when roasting cocoa at 140 °C for 30 min. Different studies demonstrate that most ochratoxin A is concentrated in the shell fraction and just a small part of the toxin contaminates the nibs (Amezqueta et al., 2005, Gilmour and Lindblom, 2008 and Manda et al., 2009). About 48% (25–72%) of the toxin is physically removed by industrial shelling (Gilmour & Lindblom, 2008), while hand-made shelling can reduce 50–100% of ochratoxin A contamination (Amezqueta et al., 2005 and Manda et al., 2009). Regarding cocoa mass and chocolate, the ochratoxin A reduction reached 28.9% with the grinding of nibs (70 °C for 3 h). Considering the data from Boudra et al. (1995) in wheat, less than 20% would be expected. Additionally, 36.5% of the decrease was achieved in the chocolate when compared with cocoa mass due to the dilution caused by ingredient addition.