Production of chocolate containing Flaxseed powder and evaluation of some qualitative properties

Chocolate is a mixture of roasted cocoa beens and very tiny particles of sugar with cocoa butter .Cocoa contains more than 400 compounds, including: fat, protein, starch, fiber, cafein, teobromin and phynil ethyl amine. Despite the existence of high level of anti-oxidants in chocolate composition, the associated product would be expected to have small amount of essential fatty acids (omega-3). Nowadays, in spite of receiving small essential fatty acids, anti-oxidants and fiber in daily diet, the requirements should be remedied by consumption of other foods containing some of needed compounds. There is a demand for consumption of food containing essential fatty acids, anti-oxidants and fiber in daily diet. Oilseeds are rich sources of essential fatty acids, fiber, antioxidants and lignans. Among oilseeds, flaxseed contains high level of α- linolenic acid – and it has other compounds such as tocopherols, fiber and lignans.
Flaxseed powder was used at the levels of 0% (control sample), 5%, 10%, 15% and 20% in the formulation of chocolate. The chocolate samples were kept at temperature of 18- 20 at relative humidity less than 50 percent. The qualitative properties of samples including water content, fat content, fiber, amount of essential fatty acids, acid index and peroxide value were determined. The samples kept for 3 month and the mentioned parameters determined every 15 days.
The results showed that adding flaxseed into chocolate decreased the saturated fatty acids content however the amount of essential fatty acids increased. Adding flaxseed into chocolate increased moisture content and the differences were significant. The maximum moisture content were seen in samples containing 20% flaxseed in the end of day 90 and the minimum content belonged to control sample in day one. The maximum fat content belonged to control treatment and the minimum belonged to sample containing 5% flaxseed powder. Also, acid index and peroxide values showed an increasing trend as flaxseed powder was increased. In addition, the maximum acid index (0.303 mgKOH/g) and peroxide index (1.875 meq/Kg) belonged to sample containing 20% flaxseed powder. The minimum acid index (0.18 mgKOH/g) and peroxide value (0.5 meq/Kg) observed in control treatments. Although the increasing in acid index and peroxide values were not significant, but they were in the standard ranges.
As a general result, it can be stated that by using flaxseed powder in the production of chocolate, a functional food with nutritional properties can be proposed for consumers.