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Color isn't just visual—it's emotional. It shapes how we feel about the food we eat and the trust we place in the brands behind it. Now, more than ever, that trust is being tested. With growing evidence that synthetic food dyes like Red No. 40 and Yellow No. 5 may harm children's health, and with global regulators stepping in, food manufacturers face a moral and market imperative: it's time to go natural.

The 2025 Make America Healthy Again (MAHA) Report has sent a clear signal—reformulate or be left behind. But moving away from synthetic dyes isn't just about compliance. It's about delivering safer, cleaner, and emotionally resonant food experiences. And that’s where HunterLab comes in.

Why Synthetic Food Dyes Are Being Banned

From hyperactivity in children to outdated FDA safety standards, synthetic dyes have become a public health concern. The MAHA Report, backed by federal agencies, is pushing for urgent reevaluation. Europe has long since labeled or banned these additives—and the U.S. is finally catching up.

For food brands, the message is clear: if you're still using petrochemical dyes, your products—and your reputation—are at risk.

Scientific Challenges of Going Natural

Switching from synthetic to natural colorants isn’t easy. Food scientists must solve for:

• Stability: Natural dyes degrade in heat, light, or acidic conditions.
• pH Sensitivity: Color shifts based on a product’s pH.
• Flavor Impact: Many natural pigments affect taste.
• Consistency: Batch-to-batch variation in natural ingredients.
• Supply & Cost: Natural colors are costlier and harder to scale.
  

Plastic plaques play a crucial role in evaluating the color and appearance of plastic pellets, serving as a reliable medium to transform raw materials into a tangible, uniform surface for precise analysis. These plaques are pressed under controlled conditions, allowing manufacturers to assess how the pellets' color manifests when formed into a flat, consistent shape. To further enhance their utility, plaques can be produced with varying surface characteristics, such as different gloss levels and textures, to evaluate the visual impact of these properties on color perception. This process ensures that the final product meets both aesthetic and functional requirements, providing a critical quality check in industries where appearance consistency is paramount, such as automotive, consumer goods, and packaging. 

Opacity and Color Measurement

Opacity refers to a material's ability to prevent light from passing through. When measuring color in opaque materials, we focus on reflectance. Reflectance is how light interacts with the plastic's surface and reflects to our eyes. Visual color comparisons are unreliable due to limitations in human color perception and the inability to account for texture variations. Spectrophotometers can standardize conditions to ensure the measurement is consistent and repeatable. 

Spectrophotometers are prominent devices in many industries and offer value for many purposes. The concentration of a chemical can be determined using spectrophotometry data. Constructing a calibration curve is one of the ways users employ spectrophotometers. This technique, much like the device, works across many applications. At HunterLab, we specialize in spectrophotometers and support operations that create calibration curves. Calibration curves have applications in several domains, including analytical chemistry and pharmacology.

What Is a Calibration Curve?

A calibration curve, also known as a standard curve, is a way to identify the concentration of an unknown substance. It calculates the concentration of the unknown material and quantitation by comparing the sample to a set of known concentration reference samples. The data fits into a model that predicts unknown concentrations. The concentration of the material causes a change in the analytical signal or instrumental response, as demonstrated by a calibration curve.

Calibration curves are beneficial for compounds that directly absorb light. Typically, a dye consists of molecules that absorb or reemit light, and spectrophotometers can measure that reaction. Begin with a known chemical, measure its absorbance or color attribute, and then graph it. Second, calculate the absorbance of the unknown sample, plot it on a graph, and apply a calibration curve to get the estimated concentration. 

These curves use data points of substances at varied concentrations, and researchers can use these curves to find where an unknown substance plots. An ultraviolet-visible (UV-Vis) spectrophotometer measures the absorbance of a chemical that absorbs light in the ultraviolet or visible parts of the electromagnetic spectrum. This system of identifying unknown substances is valuable to many industries. For example, a calibration curve for the food industry may chart food dye concentrations for gelatin.

Other applications can include:

• Pharmaceuticals
• Paints
• Plastics
• Chemical production

Simply put, a calibration curve in spectrophotometry is helpful in any situation where a substance is unknown.

How to Make a Calibration Curve

To make a calibration curve, you need the following:

• A standard solution
• A solvent for dilution
• Pipette and tips
• Five microtubes
• UV-Vis spectrophotometer

Key steps include:

• Standard preparation: Create a concentrated standard solution and dilute it to generate five multiple known concentrations.
• Sample measurement: Using a spectrophotometer, measure each standard solution and your unknown samples at a wavelength of interest or as specified by a colorimetric index, such as the Yellowness Index.
• Data analysis: Plot the measured result (y-axis) vs. concentration (x-axis)to establish a linear calibration curve. Use statistical software to fit the data to a linear regression equation (y = mx + b) and determine the coefficient of determination (R²) to assess the goodness of fit.

How a Calibration Curve Is Used

Calibration curves are used in many scientific areas to calculate the quantity of unknown chemicals in a sample. Here are some popular applications:

• Environmental monitoring: Calibration curves are essential for measuring environmental health. They may be used to determine the concentrations of contaminants in soil samples, such as heavy metals or pesticides.
• Pharmaceutical quality control: It is critical to ensure pharmaceuticals are effective and safe. Calibration curves are used to accurately measure the quantity of active drugs and other components in pharmaceutical samples.
• Food and beverage analysis: Calibration curves play an important role in guaranteeing the quality of food and drinks, from monitoring caffeine concentration in beverages to ensuring vitamin potency in fortified products.

What Is an Ultraviolet-Visible (UV-Vis) Spectrophotometer?

The process of turning raw cocoa beans into powder takes many steps. Slight variations throughout any stage could create differences in the final product. As a quality manager in the manufacturing of cocoa, you look to avoid process variations that could decrease cocoa powder quality. 

A spectrophotometer is a powerful tool for cocoa quality control. It allows you to quantify the color of the powder and its raw ingredients to identify any differences. Assessing color data throughout various stages lets you see where variations arise so you can more knowledgeably adapt your processes. 

Understanding Process Variation in Cocoa Powder Production

Process variation refers to fluctuations during production that may cause deviations from the expected outcome. In cocoa powder production, variations might include a higher roasting temperature, which creates a darker powder. Some types of process variations happen naturally and won't cause a significant change in the final product. In more severe cases, a variation could lead to substantial changes, which may require disposing of a batch or spending additional time fixing it. 

Where Does Process Variation Appear?

Cocoa powder production involves numerous stages, where even a slight change in each may influence the outcomes. Process variation occurs for different reasons, including a lack of standardization, human error, or random fluctuation. 

Some examples of process variations that influence appearance include:

• Raw materials: Cocoa beans have a natural genetic variety that influences color. 
• Processing: Changes in time, temperature, or other factors during fermentation, drying, roasting, and grinding could change the appearance. 
• Chemical treatments: Dutch-process cocoa powder undergoes alkalinization, which makes it appear darker. Changes in the alkalinization may influence the lightness. 
• Equipment standardization: Roasters and grinders perform differently depending on contamination from previous batches or setting changes.

Environmental factors: Temperature, humidity, and other factors influence appearance when introduced during drying and storage.

In the United States, milk is generally purchased in liquid form, and milk powder is not regarded as a stand-alone dietary staple. Rather, powdered milk is primarily used as an ingredient in other products, such as infant formula, candies, and other edible goods. 

However, for much of the world, powdered milk is the primary source of milk product, particularly in developing countries with scarce transportation, storage, and refrigeration resources. Its versatility, high nutrient concentration, and long shelf life make it invaluable to the lives of millions worldwide, an essential part of food aid supplies, and a key component of the global dairy industry. As markets for milk powder continue to emerge and expand, manufacturers must increasingly engage in highly developed quality assurance practices to guarantee consistency, safety, and palatability.

Image Source: Flickr user Alan Levine

Protecting Brand Integrity Through Color Precision

Inconsistent ingredient color can cost manufacturers millions in rejected batches, regulatory setbacks, and lost consumer trust. For global ingredient leader Kemin Industries, ensuring color accuracy is not just an aesthetic concern—it's central to product quality and customer satisfaction. That’s why Kemin relies on HunterLab's advanced color spectrophotometers to protect the integrity of over 500 ingredient solutions across food, pet nutrition, and more.

Operating across more than 20 countries with 15 production facilities, Kemin faces the complex task of maintaining visual uniformity in highly diverse ingredient forms. From powders and granules to liquids and pellets, their customers expect one thing: consistency. And in today's competitive baking and snack markets, even slight color deviations can signal oxidation, processing errors, or shelf-life risks.

The Challenge: Detecting Oxidative Change Before It Affects Quality

Lipid-based oxidation is a persistent challenge in the baking and snack industries. As fats and oils degrade, they visibly darken ingredient color—even before other sensory qualities change. These early shifts can result in customer dissatisfaction or failed quality checks.

For Kemin, early detection of these subtle changes is essential to delivering on their promise of quality. They needed a solution that was:

• Sensitive enough to catch imperceptible color shifts
• Scalable across facilities and ingredient types
• Easy to operate with minimal variability between users

Color is one of the first sensory processes humans experience. It can alert us to potential danger, like the orange of a safety cone, or tell us what flavor we might expect from a piece of candy.

Long-term changes to color appearance can have negative impacts — a dusty pink fire engine isn't going to draw attention as effectively as a bright red one. Learning about color stability and understanding its importance, challenges, and the best way to ensure it can help you prevent unwanted deviations from the intended, expected, and desired results.

Defining the Stability of Color

In its simplest terms, color stability refers to how well a material can maintain a consistent color throughout its life span. 

It's important to note that color stability substantially differs from color consistency and constancy. While maintaining those traits is also vital, these terms refer more to eliminating chromatic variations across batches, production lines, facilities, and observation conditions like illumination.

Factors That Can Impact Color Stability

Multiple factors can cause alterations in chromaticity as time passes. As a result, changes can arise during any manufacturing stage and throughout material storage and distribution. Excess exposure to the following can impact color stability:

• Moisture
• Oxygen
• Light and UV rays
• Extreme temperatures
• Chemicals

The Importance of Color Stability

Maintaining color over time is vital for several reasons.

Quality

Color and quality are inherently intertwined. Chromaticity that meets a consumer's expectations encourages them to form a positive brand image. When color conforms to industry standards, it also showcases your company as one committed to best practices. Color stability helps support these outcomes by ensuring long-lasting durability, which boosts perceived value.

Safety and Compliance

In many products, color stability goes hand in hand with safety. Consider goods like reflective safety tape, camouflage military uniforms, and edible oils, where color alterations over time can impact visibility or indicate potential contamination that would make it unsafe for consumption. Additionally, products whose color maintains acceptable tolerances in highly regulated industries prevent unnecessary fines or penalties.

Appeal

Customers may see color as the primary determinant in their purchasing decisions for certain items, like vinyl siding and roofing shingles. Remodeling a home exterior is a significant investment that consumers expect to last for years. Customers don't just want it to look good now — they want to know the color they see at first is the color they can expect it to stay, even after long-term exposure to the elements.