Colorants
Pages 125-128
DOI: https://doi.org/10.1094/1891127004.015
ISBN: 1-891127-00-4
Abstract
Topics Covered
- Handling Colorants and Maintaining Color Quality
- Handling Water-Souble Colorants
- Preparing Water-Soluble Colorants for Use
- Factors Affecting Colorant Quality
Introduction to Chapter
When a shipment of a food ingredient arrives at a production facility, it is customarily inspected to determine whether or not it meets specifications. This may not always be necessary, especially in the case of primary certified food colors. Not only does the colorant manufacturer generally analyze every batch of colorant with ultramodern instrumentation, but, in the United States, FDA also conducts an independent analysis and certifies that every batch meets the U.S. purity specification (hence the term “certified food colors”). The FDA certification number is included on the label of every container and on every invoice of material certified in the United States.
There are two methods for checking the strength of a particular shipment of certified food color: titration with titanium trichloride (which is not recommended for blends) and spectrophotometric analysis. Details of these methods are beyond the scope of this book but are available from colorant suppliers.
A more common situation is the need to determine whether a given batch of blend will provide the desired color in the finished product. To make this determination, a random sample is taken, and the visible spectrum of the sample is generated and compared with the spectrum of the standard. If the two match, the shipment is accepted. As a further check, the colorant is usually inspected visually after it has been prepared for the spectrophotometric evaluation. It is important that the colorant be checked after it has been dissolved rather than examining the dry colorant in its container so that small, unimportant changes in physical characteristics that alter the colorant's outward appearance do not lead to erroneous rejection of a shipment.
