Importance of Texture Measurement

By Marc Johnson, Contributing editor

Texture is one of the most important characteristics of a food: If a consumer bites into a soggy cracker or swallows a spoon of chewy ice cream, its unlikely theyll be back. Texture analyzers can help product designers ensure the target texture from the lab to the consumers kitchen.

Texture measurement is an increasingly critical component of every food companys product development effort.  Many external forces on food companies impact the texture of their products and can affect consumer acceptance (new products, health demands, supplier changes, ingredient changes, etc).  Companies are increasingly quantifying these impacts with modern texture analyzers. 

The following four trends are forcing food manufacturers to change their product development efforts

Reformulating products

Food manufacturers must be responsive to consumer demands and trends, no matter how lasting or fleeting those trends are.  Consumer expectations often are very difficult to achieve, e.g. gluten-free pizza with the same textural qualities as one made with normal wheat flour.

Trends with textural implications Include the demand for products with low salt, low fat, fewer carbs, gluten-free, and less sugar. Consumers increasingly want foods with simpler ingredient labels, higher nutritional content, or ingredients that achieve certain health claims.  Reformulation demands can also be due to business reasons such as the need for alternative ingredients or suppliers to meet cost-reduction goals.  Some trends, such as healthier vegetarian products or products with cleaner, simpler labels, may have longer staying power because they appeal to new generations of younger consumers. 

While some of these trends may be fleeting, new companies and products have emerged to serve these markets, so opportunities should not be discounted. All require manufacturers to quantify the textural implications of different formulations on their existing, brand-extension, and new products. 

Doing more with less

Companies have become more efficient and streamlined their operations, so laboratories that are staffed with fewer scientists and factory floors with fewer QC technicians.  However, workloads have increased with a proliferation of new products, brand extensions, packaging variations and production volumes. So that fewer workers can do more with less, instruments must be flexible enough to quantify the textural attributes of as many products as possible.  Additionally, the same instruments are often dual-purposed to test product packaging.  This allows all scientists and technicians to conduct the necessary texture analyses on the same instrumentation and software platforms. 

As consumers have demanded products with more subtle textures, the methods capable of discerning differences have also become more sophisticated.  Companies need to conduct increasingly more complicated texture tests, requiring texture instruments which can perform these complicated analyses with very simple user interfaces. 

Push-button simple" deployments of flexible texture analyzers allow companies to maintain production and development velocities with fewer instruments, fewer employees, and lower training costs.

Instrumental textural analysis

Sensory panels still remain absolutely vital tools for companies as they benchmark products against consumer expectations.  However, sensory panels are expensive to train, are not easily deployed for the duration required for comparisons of multiple formulations and batches, and cannot be deployed across multiple shifts and multiple plant locations.  Internally maintained panels can also be politically influenced by the participation of senior management. 

Companies are increasingly establishing instrumental texture methods for their products which correlate with sensory judgments.  They can then deploy texture analyzers in R&D labs or quality control situations Plus the instruments can be used during all shifts and across multiple plants.  Texture analyzers can also discern the impact of subtle formulation changes more clearly than sensory panels.

Texture analyzers offer practical, cost effective, flexible and precise solutions for meeting the ongoing need for textural evaluations of both new formulas and production batches.   

Analyze this: The instrumentation

Texture analyzers are instruments that measure force as products are compressed, punctured, snapped, sheared or pulled apart.  High quality texture analyzers work by combining sensitive calibrated load cells, precise stepper motors with programmable machine instructions and intelligent analysis.  Fixtures and probes are mounted on the load cells and driven into target products in order to imitate consumers experiences.  For example, to imitate a consumer biting through an extruded cheese puff, a thin knife blade can be mounted on a texture analyzer and driven into the snack at speeds comparable to someones jaw (See Picture 1 and Figure 1).

 The resulting force curve will show increasing force from when the blade encounters the products exterior until it breaks into the snack.  That section of the plot will correlate with consumers sensory perceptions of stiffness and brittleness.  As the blade cuts through the subsequent internal cells, the force plot will have a jagged profile, which will correlate with sensory scores for hardness and crunchiness. Some instruments have a program that automatically analyzes the curve and provides quantifiable metrics about crispness, brittleness, hardness, and crunchiness and how all of those parameters change over time.  

Almost every type of food product can be similarly tested with a variety of fixtures and probes.   While each combination will generate a different force profile, almost all of them can be tied back to consumers sensory judgments or to product behaviors that are relevant to food manufacturers.

Textural expectations

Retail and industrial customers now have much more refined expectations of desired product textural attributes.  The demand is being met with increasing numbers of new products, brand extensions and formulations. Just look at consumers appetite for coated crunchy products, nutrition and granola bars of every type, as well as new styles of yogurts.  Low-end texture analyzers only measure a soft vs. hard" scale which cannot even discern the targeted, subtle attributes key to products with nuanced textures.

More skilled manufacturing and packaging techniques can deliver the desired textural attributes that customers are now demanding (e.g. crispy, crunchy, brittle, resilience, creamy, thick, chewy, tough, slippery, crumbly).  However, these attributes need to be measured and maintained throughout the products shelf life, which can only be quantified with full-featured texture analyzers with sophisticated software packages.  High-end texture analyzers with calibrated microphones can even capture the acoustic profile of crispy and crunchy products.    All of these tools and techniques, along with sophisticated software that automatically calculates textural attributes relevant for individual products, have allowed manufacturers to cost-effectively precisely quantify and control the highly desired textural attributes that consumers are demanding.

Armed with better tools and a lexicon to describe textural attributes, food scientists today can now measure subtle differences in texture. These measurements help them quickly create reformulated products that retain all the desirable characteristics of targeted products without compromising important elements such as mouth feel.

Market forces and recession economics have changed the balance of power between food manufacturers and consumers.  Companies are reformulating their products more often, conducting product development efforts with fewer resources, requiring more testing of products textural attributes, and delivering products with more sophisticated or subtle textures. Using advanced texture analyzers in food product development and production efforts effectively addresses each of these challenges.

Marc Johnson is president of Texture Technologies, the exclusive North American Distributor of Stable Micro System's family of texture analyzers, including the TA.XTPlus, TA.HDPlus, andTA.XTExpress. He joined Texture Technologies in 1993 and has been developing test methods and fixtures for quantifying the texture of food products for the last 20 years. He is a frequent lecturer at industry, university and corporate meetings on topics related to texture measurements for the food, pharmaceutical, cosmetic and adhesive industries. Texture Technologies provides fortune 500 companies and major universities with product testing solutions.