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Clarity is a critical aspect of liquid product quality in many industries, and modern consumers combine it with color when evaluating whether to buy a product or trust a brand. As a result, scientifically and objectively quantifying haze is essential to achieving quality goals and maintaining customer satisfaction.

What Is Haze and How Does It Alter the Appearance of Liquids?

In its simplest definition, haze is scattering of light produced by small particles in a sample. Suspended particles within a liquid also scatter light, leading to turbidity — a cloudy, milky, or opaque appearance.

Transmission haze occurs in transparent goods and liquids, like clear plastic preforms or bottled water. As light passes through the sample, factors like surface texture imperfections and impurities scatter the energy.

Primary Causes of Haze in Liquids

In liquids, a natural interaction between proteins and polyphenols usually causes measurable turbidity. Other potential causes include poor-quality raw ingredients, such as infected barley used in beer brewing or particulate residues from filtering processes.

The Importance of Haze to Consumer Perceptions

Clarity is necessary in liquids to signify quality and safety.

Turbidity in beer can be either desirable or undesirable, depending on the consumer's preference. Many manufacturers continually aim to control turbidity in beer since its presence can negatively impact taste and shorten shelf life. Others use turbidity as a competitive advantage, crafting hazy IPAs that consumers perceive as more flavorful. Similarly, some winemakers prefer haze as a marker of authenticity and a natural by-product of fermentation.

Other liquids also rely on haze to meet consumer expectations or generate a favorable customer opinion. For example, a haze in fruit juices can spur more sales by promoting the perception that nutritional value is higher. Manufacturers can create the haze naturally or use additives to produce the intended result.

Powders play a vital role in many industries, from food products like cocoa powder to minerals and the lifesaving medications pharmaceutical manufacturers create. Their colors must be consistent and meet customer expectations to support quality initiatives, conformance with industry standards, satisfaction, and, ultimately, profitability. Spectrophotometers provide the easiest, fastest, and most objective way to quantify color to help you reach these goals. 

Key Features to Evaluate

Learning what key features to evaluate as you explore the spectrophotometric solutions available can help you make a more sound investment.

Minimum Sample Sizes

Some ingredients, like certain high-value spices and active pharmaceutical components, are incredibly expensive. Reducing the size of the sample needed for accurate measurements is key to controlling waste and limiting sampling costs. A spectrophotometer that offers the smallest sample size possible will deliver the most value for many applications and significantly lessen the expenses involved with high-value powder production.

Sample Compatibility

Powders present unique challenges in color measurement. Many have nonuniform textures and varying particulate sizes requiring careful sample preparation to promote accurate outcomes. Their opacity demands specialized optical geometry that captures data through reflectance. A thorough, careful analysis of your powder's physical properties will help ensure the spectrophotometer's capabilities align with your needs.

Index and Scale Library

Many industries have specific industry scales or indices they use to ensure their products conform to standards. Samples may rely on different color spaces, such as the CIELAB scale often used to measure barium sulfate. Evaluate the spectrophotometers you're considering to ensure they're capable of providing data within the scales that apply to your industry.

Effective Bandwidth

Regardless of which wavelength you measure in the visible spectrum, you need to ensure the device you select has suitable effective bandwidth for accuracy. This term refers to the range of wavelengths interacting with a sample at a given moment. A narrow effective bandwidth coupled with high radiation throughput helps ensure strong signals and background noise reduction. This configuration allows for more precise readouts since the spectrophotometer can isolate smaller wavelength ranges.

Integration Capabilities

Ideally, the spectrophotometric solution you choose should fit effortlessly into existing workflows instead of forcing you to adapt proven processes. Features like universal compatibility simplify integration. This trait allows the spectrophotometer to connect to and communicate seamlessly with other devices. In addition, selecting a model with many connectivity options makes data export and transfer to your quality management systems fast and easy.

Viewing Area

While finer powders may lend themselves to a smooth, even sample surface, sample averaging is critical for measuring color in powders with larger particles and nonuniform characteristics. These traits can lead to shadowing that can create measurement discrepancies when only capturing data in one reading. Taking multiple measurements across larger viewing areas and averaging them helps resolve those challenges, so it's essential to consider viewing area size as you narrow down the options.

HunterLab’s Global Commitment: Stability, Service, and Support Amid Supply Chain Pressures

As global trade conditions continue to evolve, businesses across industries are navigating new levels of complexity. At HunterLab, we understand how these pressures can affect your planning, operations, and service expectations. That’s why we’re committed to ensuring that our color measurement solutions remain consistent, available, and fully supported — no matter the global environment.

For over 70 years, HunterLab has helped customers around the world maintain color quality with precision instrumentation and reliable service. In times of uncertainty, that commitment only grows stronger.

Why Global Conditions Matter in Color Measurement

Whether you’re formulating products in food, plastics, chemicals, or textiles, accurate color measurement is essential to brand consistency and quality control. But behind every precise measurement tool is a complex global supply chain — and today, that landscape is changing rapidly.

Businesses are feeling the effects of:

- Increased transportation costs

- Longer lead times due to port and customs delays

- Supply constraints for critical electronic and optical components

- Shifts in international trade policies and sourcing strategies

This environment has the potential to impact availability and cost structures across the instrument manufacturing industry. But at HunterLab, we are actively working to minimize that impact for our customers and partners.

Color measurements provide valuable information for food producers, manufacturers, and distributors. As one of the first things consumers are bound to notice when making purchasing decisions, color makes an impression. Consistent appearance in any food is key to delivering what consumers consider natural and fostering brand loyalty.

When measuring color, every ingredient counts, even the ones generally considered colorless and of little effect. Baking powder often falls into this designation, but this ingredient has a well-defined color that consumers expect. Here's what you need to know to produce a valuable commodity for baking.

What Is Baking Powder?

Baking powder is one of the most useful tools in any baker's or homeowner's cabinets. It's a combination of baking soda and a powdered, edible acid, such as cream of tartar. It prompts items like quick breads to rise and combine properly throughout the cooking process. Most formulations also include cornstarch, which prevents the formula from clumping and reacting before you're ready to use the powder.

In plant-based protein development, many researchers have uncovered beet powder as an essential ingredient for meat alternatives. This vibrant purple-red material can create the signifying pink color we often associate with real meat, but it needs to be used strategically. Too much beet powder in meat alternatives may make the plant-based protein hot pink, and too little may lead to an unappetizing gray.

Create Quantitative Color Measurements With Spectrophotometry

Color is a measurable science, even if it seems like a subjective quality. We perceive color based on how much an object transmits and reflects the wavelengths of light, and we can measure this transmittance and reflectance to quantify color.

Spectrophotometers achieve this measurement with a single light source separated into each individual wavelength. These different wavelengths appear as different colors. In the visible spectrum range, violet has the shortest wavelength and the highest frequency. Red has the longest wavelength and the lowest frequency.

A spectrophotometer will isolate selected wavelengths and direct them at a sample. Then, a sensor will measure how much of the light is reflected and transmitted. The colors an object transmits or reflects are the colors we see, so beet powder reflects violet and red. The spectrophotometer will create a data set of the different wavelengths for users to understand the color makeup of a sample.

Spectrophotometers empower manufacturers across numerous industries to capture accurate color and spectral data. These measurements support regulatory compliance, conformance with industry standards, and quality assurance that keeps customer satisfaction and loyalty high. Modern solutions offer measurement through either transmission or reflectance optical configurations.

Learning more about these approaches, their ideal substrates and applications, and their differences will guide you to the best solution for your color measurement needs.

Understanding Color Measurement

Light is the foundation of color measurement, with its wavelengths in the visible spectrum ranging from violet at 380 nanometers to red at 780 nanometers. The energy a light source provides varies across the spectrum depending on the light source. When it encounters matter, its wavelengths are either reflected, absorbed, refracted, transmitted, scattered, or diffracted. The object's chemical makeup helps determine what photons it will absorb versus those it emits or transmits. These emitted or transmitted wavelengths then enter the human eye, stimulating its photoreceptors. Emitted or transmitted wavelengths are the colors our eyes ‘see’ depending on where the energy falls within the visible spectrum.

Color perceptions vary between humans, making visual comparisons unreliable and underscoring the need for scientific color measurement solutions. Spectrophotometers simplify the task by analyzing and quantifying color in widely accepted color spaces like CIELAB and CIE XYZ. Transmission and reflectance are the two primary configurations spectrophotometers use to capture and report color and spectral data.

Color Measurement Through Transmission

When spectrophotometers measure color by transmission, they pass light directly through the sample. An optical sensor on the opposite side of the sample collects the energy for analysis and reporting.

The Science Behind Transmission Measurement

Measuring wavelengths through the transmission of color quantifies them into a ratio called transmittance. In scientific terms, transmittance is the percentage of incoming light that passes through a sample. The sample will also absorb a certain amount of the energy, requiring precise calculations using the Beer-Lambert Law, which describes how light is absorbed when it passes through matter.

Transmission measurements typically need at least 30% of the source light to pass through the sample with the light source at a perpendicular angle.

Key Considerations for Choosing Transmissive vs. Reflective Measurement

Transmission measurements work for transparent to translucent materials that allow 30% or more of the light to pass through — even if the surface is textured, like etched glass.

Opaque samples, which don’t let enough light through, are better measured using reflectance.

Applications for Transmission Color Measurement

Common applications for transmission color measurement include quantifying color in:

• Foods and beverages: Products ranging from edible oils to fruit juices and food dyes are compatible with transmittance measurement.
• Plastics: This approach is widely used in the plastics industry for food and beverage containers, transparent sheets and film, eyeglass lenses, and medical equipment like syringes, IV bags, and other clear medical devices.
• Chemicals: Use this method to quantify color in motor oils, lubricants, and petrochemicals.
• Pharmaceuticals: Injectable solutions and liquid medicines to monitor purity and detect any unwanted color changes.

Transmittance is also the most reliable color measurement approach for everyday products like clear liquid detergents and ophthalmic lense

Color measurement is a precise science requiring an objective, practical, and effective approach. Accurate data and consistency improve customer satisfaction and product quality across industries ranging from food to plastics. When you know the most common mistakes made in taking accurate measurements, you can proactively prevent or avoid them and capture data you can have confidence in.

1. Relying on Subjective Descriptions and Visual Assessment

People perceive color differently, so subjective descriptions like “navy blue” can't accurately quantify it. In contrast, measuring according to the CIELAB color scale might give you a value of L*= 15, a*= -6, b*= -25, so you'll have an exact number to compare. 

Visual assessment leads to color measurement problems due to a lack of optical memory and physiological dysfunctions that influence perception. Even trained eyes with superior detection ability can become fatigued, compromising accuracy. 

2. Not Using a Software Program

A software solution simplifies measurement collection and comparison, making it a powerful tool for enhancing spectral data analysis.

3. Not Considering Environmental Factors

Metamerism describes the phenomenon where two colors match under one light but not another, which creates issues with color consistency. A spectrophotometer, which contains a standard light source, combats this phenomenon. Other environmental factors that can influence color include temperature and humidity, which alter the way a material interacts with the wavelengths. Controlling these within your facility can help promote more accurate measurements.