Spectrophotometric Color Measurement Keeps Ketchup Red as Manufacturers Eliminate Preservatives

ketchup color spectrophotometer
Ketchup is one of the most popular condiments in North America. Photo by Dennis Klein on Unsplash

Consumers are demanding more natural, healthier food virtually across the board and the condiment industry is no exception. The ketchup segment of that accounts for more than $8 billion annually, with the vast majority of ketchup consumption happening in North America.1  Despite this high figure, the market is declining due in part to increased awareness of the risks of preservatives and high sugar typically present in the popular condiment. As manufacturers seek out ways to increase the appeal of ketchup by eliminating these additives, they may need to adjust their formulas to account for color.

Ketchup, however, can be a surprisingly finicky condiment when it comes to color integrity. Everything from the shade of the tomato to cooking duration and temperature could result in an undesirable color, which is either too dark or too pale. As manufacturers adjust their ingredients, the need to find ways to ensure ketchup color is still visually appealing to consumers remains. Using spectrophotometers in the process of creating ketchup is an ideal solution.

ketchup color spectrophotometer
Ketchup is a staple many are shying away from due to health concerns. Photo by Charisse Kenion on Unsplash

Issues in Maintaining Tomato Red Ketchup

Before the 1900s, commercially produced ketchup included highly harmful preservatives, including borax salicylic acid, benzoate of soda, benzoic, and formaldehyde.2 This practice was outlawed in the early part of the 20th century, and today, manufacturers rely on the natural acidity in tomatoes along with sweetening agents that provide a longer shelf life, like high fructose corn syrup.

However, consumers are increasingly demanding that manufacturers reduce sugar content and artificial ingredients in foods and the declining market for ketchup shows they’re willing to forgo foods that don’t meet these standards. As a result, many manufacturers are striving to eliminate or reduce unnecessary additives and high fructose corn syrup from their products. Unfortunately, as formulas change, so does the ketchup color. In fact, there are a number of factors that can cause the color of ketchup to change, including:

  • Oxidation: With exposure to air, ketchup color will darken. To control this, manufacturers of ketchup use a closed container mixing process and may re-aerate the product if air exposure results in darkening of the product.
  • Tomato Quality/Ripeness:  Both the quality and the ripeness of the tomato will have a direct impact on color. Mixing a tomato that’s not entirely ripe into the paste could result in it having a greenish or yellow cast while using poor quality tomatoes could create a mixture that’s closer to pink than red.
  • Heating and Cooling: Ketchup must be heated to approximately 190 degrees Fahrenheit to kill any contaminants or bacteria. It must also be rapidly cooled to avoid losing flavor after processing. Both these steps can cause the color of the ketchup to change.
  • Concentrations:  About one-third of a ketchup’s acidity and sugar content comes from the tomato paste in the mix. The rest comes from the addition of distilled vinegar and sweeteners like high fructose corn syrup. As these concentrations change to account for the elimination of undesirable ingredients, the color will change as well.

Changing ingredients—including removal of undesirable ingredients—in a mix will change processing and directly impact the color of ketchup when it hits store shelves. This presents a major challenge for ketchup manufacturers, who are working with one of the most iconic food colors in the world. To ensure that ketchup maintains its well-known color while addressing consumer concerns about preservatives and sugar, manufacturers can turn to spectrophotometric color measurement for monitoring and correcting these changes.

ketchup color spectrophotometer
Spectrophotometers can be used to gauge optimal harvest time for tomatoes. Photo by Chad Stembridge on Unsplash

Using Spectrophotometers in the Ketchup Production Process

Spectrophotometric technology that’s designed to measure color based on how the human eye sees it can be an important tool in ketchup color creation. These instruments can be used to obtain color data at various critical points in the production process which can then set the standard for new formulations. With the ability to objectively measure all colors, manufacturers can eliminate waste in the color creation process by reducing unknowns and correlating color processes and ingredients to refine production practices. This is particularly important in the development of new recipes, such as those that eliminate sweetening agents.

Spectrophotometers can be used in virtually all parts of the ketchup production process, from selecting tomatoes to testing samples after bottling:

  • Selecting tomatoes in the field: Tomatoes must reach a proper stage of ripeness before being used in mixing ketchup. Color can be tested while plants are still on the vine with a spectrophotometer, allowing farmers to optimize harvests.  
  • Monitoring the mix during processing: The color of ketchup can fluctuate during processing, meaning consistent monitoring is needed. Spectrophotometers, including on-line instruments that continuously monitor your product in real time, can be added to simplify color management.  
  • Checking finished product: Manufacturers can use a non-contact spectrophotometer for measuring the color of the final product prior to bottling. This quality control step allows manufacturers to evaluate correctness of processing and establish their product’s quality before sending it off to retailers.  

One of the benefits of using spectrophotometers in the creation of new formulas is that these devices allow for faster calibration of recipes, so manufacturers can pivot as consumer habits and preferences change. By providing you with a defined color target and giving you the data necessary to evaluate the impact of ingredients and processes on color, you can more rapidly perfect your practices, increasing the efficiency of product development.

HunterLab Accuracy

HunterLab’s highly sensitive instruments are ideal for use in the ketchup industry as they allow you to implement rigorous color quality control protocols. Manufacturers hoping to increase production as they eliminate additives can employ our top-of-the-line technologies to improve efficiency while maintaining color appeal even through major formula changes. Contact us for more information on our sophisticated instruments, customizable software packages, and world-class customer support services.

  1. “Tomato Ketchup.” https://www.statista.com/outlook/40070100/104/tomato-ketchup/north-america#
  2. “How Ketchup is Made.” http://www.madehow.com/Volume-2/Ketchup.html