The Texture of Dairy Foods is as important as flavour and colour

Texture can make or break a product’s perception. How to talk about it, how to target it and how to tap into the ingredient toolkit is a definite requirement for dairy developers. 

With everything from Greek-style yoghurt to efforts at fat reduction underscoring texture’s importance, there’s no time like the present to turn texture to your advantage.   

“In the past, consumers didn’t really notice texture until it was ‘wrong,’ such as a powdery texture in a smoothie or a slimy, cohesive texture in a sauce,” said Shana Brewer, a marketing manager at Ingredion Inc., Westchester, IL. 

“But food manufacturers are now using texture as a key differentiating quality to improve a product’s overall consumer appeal.” 

She cites as proof the uptick in front-of-package texture claims, noting that research from Innova Market Insights found the use of texture claims more than doubled globally over the last five years.

Adding to texture’s importance is the intricate manner in which it interacts with its higher-profile teammates: taste, aroma and flavour. “Texture is very important as an aim in itself and as part of the target taste-flavour-texture perception,” said Mirjana Curic-Bawden, a scientist at Chr. Hansen Inc., Milwaukee.

The texture of dairy foods

Looking at yogurt

Just consider what texture does for yogurt, a category that’s enjoyed astounding growth.

Carol Rainford, a senior food scientist at Tate & Lyle, Decatur, IL, said yogurt is 'a great example' of a category where texture matters. “A soft, smooth, pudding-like texture is preferred for traditional American-style stirred yogurt, while a typical fruit-on-the-bottom yogurt has a very firm texture. And the smooth-and-creamy yet dense texture of Greek-style yogurt is significantly different from other yogurts,” she said.

Indeed, it may be this Mediterranean import that’s created the biggest stir in dairy. “Greek yogurt has introduced a whole new texture profile to the industry,” said Vicky Fligel, business development manager for Glanbia Nutritionals, Chicago. “Consumers are now looking for creamier, thicker textures in yogurts.”

Greek-style products traditionally achieve that texture through processing — a pre-fermentation straining step that removes whey and concentrates solids, especially protein. But straining is costly and time consuming. It isn’t the only road to Greek-style success. The key to stabilising a Greek-style yogurt is the use of a modified food starch, Rainford said. The ingredient provides initial viscosity development during fermentation, keeping added milk solids from settling to the bottom, and it enhances processing stability to provide texture and mouthfeel, she said. 

What’s more, modified starches withstand pH extremes, extended storage and vigorous handling. And they can replace a portion of the milk solids to lower costs. Modified starches even help correct the dry, grainy texture that nonfat dry milk and whey proteins impart when used to fortify Greek-style yogurt bases, Rainford said.

Hydrocolloids in ice cream

But even Rainford concedes that modified starches are more effective when part of a multicomponent texturant system. “It’s the total blend of stabilisers that delivers finished-product integrity throughout shelf life,” she noted.

Essential to that blend are hydrocolloid gums. Brooks pointed out that certain starches may create a texture that can physically interfere with a clean flavour release. Such starches form films on the palate that not only block flavour expression but exacerbate the perception of graininess. This is a defect that hydrocolloids help overcome.

Consider, for example, the texturant system Brooks would build for a frozen dairy dessert like ice cream. “You might combine a freeze/thaw stable starch with a gum like tara so that the overall use level of the combined system is lower — certainly well below 6% of the total formulation,” he said.

By 'synergizing' the starches and gums, such a system permits lower use rates, promotes cleaner flavor release and strengthens the starches against retrogradation. This, Brooks said, “allows fewer and smaller ice crystals to form during freezing and thawing, and maintains more of the desired mouthfeel” in the finished ice cream.

Better yet, hydrocolloids increase the time it takes the ice cream to melt in the mouth — a desirable eating characteristic — while improving aeration and increasing overrun during the churning process.

Building a hydrocolloid textural system is an application-dependent task that benefits from the guidance of a specialist. Consider that while locust bean and tara gums both improve freeze/thaw stability and provide a short texture and creamy mouthfeel, they aren’t interchangeable.

“Tara gum happens to be silkier in texture,” Brooks said, “and therefore may be perceived as creamier in the finished product.”

It’s only natural

Hydrocolloid gums were once viewed sceptically as 'chemical' additives, but today’s consumers seem savvier about how benign — and how downright 'natural' — these plant-based ingredients are. With consumers yearning for simpler labels, back-to-basics ingredients are in order, Fligel said. Functional whey and milk proteins fit the bill, having a solid track record as consumer-friendly ingredients and texturisers that “help build viscosity and eliminate the need for stabilisers,” she said.

Bacterial cultures are another natural texturiser with a long history in fermented dairy. Curic-Bawden noted that Greek-style yogurt’s thickness, smoothness and creaminess depend not just on concentrated protein but “a great deal on culture choice. New cultures with extra-high texture give more mouth thickness and higher gel firmness, allowing for the removal of gelatin and the reduction or elimination of added non-dairy stabilisers.”

Culture strains, particularly those with a higher rate of exopolysaccharide (EPS) production, help to improve flavour, mouthfeel and creaminess, even in nonfat products, Curic-Bawden said.

This is no mean feat, because reducing or eliminating fat in dairy has dire consequences for texture, not only changing product body and thickness but muting flavour release, altering the way a product coats the mouth and playing havoc with the sensation of 'melt away' we expect when we eat it.

Still, cultures aren’t alone in conferring creaminess. Functional whey and milk proteins have an effect on texture, Fligel said. “They work well in low-fat yogurt formulations by providing a thicker texture profile — that is, fat-mimetic properties. They also provide a higher protein content without jeopardizing texture or flavour,” she said.

Protein ingredients that excel in yogurt smoothie and beverage applications help to thin out the viscosity for a smoother finish, while other options “provide an indulgent, thick and creamy texture,” she said. “Each ingredient is unique and provides a slightly different texture profile, which can help with clean-label claims.”

Rice starch is a label-friendly texturiser whose neutral taste and small starch granules “mimic the feeling of fat globules in the mouth without altering the original taste of the product,” said Rudy Wouters, vice president of the Beneo-Technology Center, Tienen, Belgium.

Such is true of inulin, too, which Beneo extracts from chicory root. Chicory root-derived inulin acts perfectly as a fat replacer in low-fat dairy products and provides a creamy mouthfeel and body, Wouters said. As a soluble dietary fibre, inulin lets Greek-style yogurt manufacturers increase a product’s fibre content. When following a traditional straining method, “It is preferable to add the inulin after the concentration process,” he said. Or, processors can include inulin in the fruit prep or syrup for fruited or sweetened yogurts, respectively.

Looking ahead

For a creamy texture, there is nothing like cream.

“Adding a bit of cream works best to improve mouthfeel and creaminess,” Curic-Bawden said. “And we now see more Greek-style yogurt offered in 2% to 3% fat.”

Fligel anticipates a similar shift across dairy emphasizing decadence.

“We expect to see more indulgent, dessert-like textures,” she said. “Creamy, higher fat, more dairy beverages and more innovation in frozen desserts.”
Brewer is excited about technology innovations that open up possibilities for dual textures, such as “combining a smooth beverage with a crunchy inclusion, or a crispy snack with a smooth outer coating. With the changing demographics in the U.S., it will be more important than ever for food manufacturers to understand the key textural trends and drivers for targeted demographic groups in identified food segments to help drive innovation and ultimately sales.”

This blog post has been adapted and summarised from:

The texture of dairy foods is as important as flavor, color | 2014-01-08 | Dairy Foods 


There is a Texture Analysis test for virtually any physical property. Contact Stable Micro Systems today to learn more about our full range of solutions.

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