Study on Correlation between Carotenoid Content and Color Features in Carrot Pwoder

Carrot has the high nutrition, health care and medicine values. Made into the powder with the microstructure, its superficial area and porosity increases evidently, the dispersivity, solubility and functionality of the products are enforced obviously and easily absorbed by human bodies. It is necessary to make researches related to influences on the carotenoid content in the carrot powder by using different drying methods for improving the quality of the carrot ultra-micro powder. However, the routine testing process, extracting the carotenoid in the carrot powder by using the extracting agent, and then measuring the carotenoid content by testing the absorbency, is very complicated and will lead to a bigger testing error. The research finds that it has a close relationship between the content and the color of the carotenoid. So, according to different drying methods (the vacuum freeze drying, the vacuum drying, the microwave drying and the hot-air drying) and different pre-processing methods (the raw carrot, the ripened carrot and the freeze dried carrot), the color characteristic of the carrot powder is obtained by using the digital photography and the image color analysis technologies, and the carotenoid content of the carrot powder is measured at the same time. On the base of these, the estimation model of the carotenoid content and the color characteristics of the carrot powder is established, and the precision of the model is evaluated and validated. The model provides the basis for the quick testing of the carotenoid content based on the digital photography and the image color analysis technologies.