study the distribution state of phytosterol and color changes of enriched yogurt with phytosterol using gas chromatography and photoshop software

phytosterols have been used for reduction of cholesterol since 1950. the high melting temperature and chalky taste are the major problems related to the enrichment of foodstuffs with phytosterols. the cristal construct of these compounds could not reduce remarkably the blood cholesterol in comparison with the fatty soluble forms. presence of free and alcoholic forms of phytosterols and also their capability in making strong linkage with nutritional matrix make difficult and complicate their analysis and distribution quality in foodstuffs. in this study the emulsion include the emulsifier, soy bean oil and water was used for dissolving and dispersing of phytosterols in water phase. then the distribution state of phytosterol in enriched yogurt was investigated using gas chromatography. because of the appearance and color are the first parameters in the evaluation of nutrition materials, digital imaging and photoshop software was used to measure the color of enriched yogurt. results indicated that the using of emulsifier and soy bean oil could be suitable approach to disperse and dissolving phytosterol in liquid phase. gas chromatography showed that it is a favorite method to measure manner of dispersing the phytosterol. in the colorimetric studding no significant differences observed between enriched yogurts and control. also result exhibited that the using of photoshop software could be the better scale in comparison with the other current method and instruments for color assay of the yogurt.