A review on analytical methods for the determination of natural colorants (green) in food commodities and beverages

Abstract

A wide variety of natural colorants are generally used for coloring food stuffs to make them more attractive, informative and reinstate the original color lost during the production process. However, in many countries the usage of natural colorants is limited due to their low stability. Green is one of the most important secondary colors as far as consumer goods are concerned due to looking fresh and natural. Chlorophyll and its metal derivatives like copper or zinc chlorophylls have been used as green colorant in food and pharmaceuticals. The regulatory authorities and food analysts have adopted precise analytical methods in assessing quality and safety of food products. These techniques mainly deal with determination of quality, quantity, colorant stability, safety and utility limits of colorants in food stuffs. These aspects are sensitively regulated by regulatory authorities as well as domestic and food suppliers. In this review, we discuss various extraction methods that are executed for extracting the chlorophyll and metallochlorophyllins from complex food commodities and beverages. In addition, different extraction methods used for food commodities have been presented. Exclusively the present manuscript reviews various analytical techniques used for the analysis of Na-Cu-Chlorophyllin (Na-Cu-Chl) employed in food products as food colorant.