Though it probably takes a back seat to taste, color is an important factor when consuming food. Society has assigned what we consider the “ideal color” for various food items. For example, consider the produce section in the grocery store, where you may find yourself attracted to particular items with the most desirable color. Those colors are desirable because you equate them to a fresher, more ripe, or higher quality product. You grab the bright yellow bananas and leave the green ones behind (unless you’re willing to wait for the green ones to ripen at home).
This consumer tendency extends to the middle aisles of the grocery store too, and affects another food category with a wide color gamut: spices and seasonings. Culinary-focused consumers rely on spices not only for taste, but also to achieve a distinct color for a dish. Because of this, spice processors and manufacturers recognize color control as an essential component of their quality processeses. They acknowledge and respond to consumer habit in order to ensure their products on grocery store shelves appeal to potential customers’ eyes. In addition to consumer-driven motivation, monitoring the color of spices can reveal other noteworthy information about a particular spice, such as geographic origin, storage conditions or processing techniques.
Unfortunately, controlling the color of a spice is often a challenge. Spices have a long, complex supply chain, and undergo more processing than produce in most cases. Processes such as grinding, washing, and distillation can affect the color of a spice, often resulting in a duller product. Unsurprisingly, spices in whole form retain their color better because more of the spice is protected by the outer shell, but these spices are generally in lower demand than their processed counterparts. Other factors that contribute to spice color variance are the color-creating pigments themselves. Pigment levels can rise or fall over time due to a number of factors, most commonly environmental. Weather, sunlight and storage conditions can all play a role.
The inconsistency in color of a spice can no doubt cause headaches for companies attempting to deliver quality, standardized products. Fortunately, the American Spice Trade Association (ASTA) has developed two methods for the analytical determination of color in spices.
- ASTA Method 18.0 Curcumin Content of Turmeric Spice & Oleoresins (revised October, 2004) Measures the curcumin content of turmeric by measuring absorbance of curcumin color at 415-425 nm
- ASTA Method 20.1 Extractable Color in Capsicums and Their Oleoresins (revised October, 2004) based on absorbance at 460 nm Used for quantifying the color of paprika and oleoresin spices
These two methods involve the determination of absorbance in acetone extracts using a spectrophotometer. Results are reported in ASTA Color Units, which is an industry-accepted quantitative scale for color.
Mérieux NutriSciences has recently launched several ASTA methods, including the two mentioned above! We are able to offer full proximate and nutritional analysis, as well as other quality indicators such as Scoville heat, Piperine, Steam Volatile Oils, and many others.