Colorants
Pages 55-66
DOI: https://doi.org/10.1094/1891127004.007
ISBN: 1-891127-00-4
Abstract
Topics Covered
- Athocyanins
- Chemical Composition
- Commercial Preparation
- Synthetic Compounds
- Considerations in Commercial Applications
- Health Effects
- Betalains
- Chemistry
- Occurrence
- Commercial Preparation
- Applications
Introduction to Chapter
The anthocyanins are probably the best known of the natural pigments. Ubiquitous in the plant kingdom, they are responsible for many of the orange, red, blue, violet, and magenta colors in plants. Their very visibility, combined with their role as taxonomic markers, has attracted the efforts of many research workers in the past 75 years. As colorants, they go back to antiquity—the Romans used highly colored berries to augment the color of wine.
In view of the ubiquity of the anthocyanins and their high tinctorial power, it comes as no surprise that many plant sources have been suggested as colorants. Francis listed pigment profiles and methods of extraction for over 40 plants as potential sources (1,2) and also listed 49 patents on anthocyanin sources (3). However, despite the large number of potential sources, only two, grapes and red cabbage, have had commercial success. More recently, elderberry, aronia (chokeberry), and black carrot have been moderately successful.
Colorants from grapes have been available for nearly 120 years, primarily from press cake as a by-product of the wine industry. Grapes are the world's largest fruit crop for processing. In 1995, the annual production of grapes was estimated to be 60 million metric tons, of which about 80% was used for making wine (4). This ensures a limitless source of inexpensive raw material for colorant production.
