LSU AgCenter researcher Witoon Prinyawiwatkul sits in a private booth where tasters can be given various food products to evaluate in terms of taste, texture and liking. (Photo by Rick Bogren)

LSU AgCenter researcher Witoon Prinyawiwatkul explains a texture analyzer that’s used to measure the hardness and springiness of food samples. (Photo by Rick Bogren)

News Release Distributed 09/17/14

BATON ROUGE, La. – Changing people’s perceptions of how foods taste – or even how foods feel in the mouth – can help direct them to more healthful food choices, said Witoon Prinyawiwatkul, a researcher in the LSU AgCenter School of Nutrition and Food Sciences.

Prinyawiwatkul is leading a team of AgCenter researchers who are evaluating how people respond to sensory differences to assess the effectiveness of changing sodium content in processed foods. They’re studying how different approaches to modifying the salt content in foods can improve the healthfulness of the food while reducing the amount of sodium.

Americans consume unhealthy amounts of sodium, mostly in the form of salt, or sodium chloride, Prinyawiwatkul said.

Although sodium is a critical element in the human body for functions as retaining fluids, balancing electrolytes and controlling nerve function, too much is unhealthy. “It’s a ‘silent killer’,” he said.

“If you don’t cook, you don’t have a choice,” Prinyawiwatkul said.

Citing results from the Centers for Disease Control and Prevention, Prinyawiwatkul said more than 90 percent of Americans consume more sodium than the recommended intake. And more than 65 percent of the sodium comes from processed foods and other retail products, 25 percent is consumed in restaurants, and the remaining 10 percent is added by consumers.

The solution to this problem is reducing sodium intake in the diet. “We can use different salts, such as potassium chloride, or simply reduce sodium consumption through a stepwise approach or both,” Prinyawiwatkul said.

Potassium chloride is the most common salt substitute, but when used at high concentrations, it imparts bitterness and a metallic aftertaste. The AgCenter researchers use sensory trials to measure consumer attitudes to taste, texture and appeal of foods with modified salt content.

In one study, researcher Damir Torrico is blending emulsions of oil and water in a process similar to making mayonnaise to see if the size of the oil droplets affects the saltiness and bitterness of the product.

While the size of the oil droplet had no effect on saltiness, Torrico discovered the emulsion suppressed the bitterness of potassium chloride, which wasn’t observed in a water solution.

The researcher now is looking at replacing some of the sodium with potassium to maintain saltiness while adding another compound to block the bitterness of the potassium.

“We’re adding potassium chloride along with bitterness suppressors to see if we can impart saltiness with minimal bitterness,” Prinyawiwatkul said. “We also want to reduce sodium and manipulate the taste bud receptors by modifying the emulsion characteristics.”

In another study, Kennet Carabante and Chuck Boeneke are focusing on reducing the sodium content of cheddar cheese.

Working in the AgCenter creamery, the researchers have changed the sodium content in typical cheddar cheese recipes to find out how the changes affect cheese quality. They have successfully produced low-sodium cheese by replacing a portion of the sodium chloride with potassium chloride and a bitterness blocker.

Carabante took the cheese to the public. In a series of taste and sensory tests, consumers rated the product with a 6.2 acceptance level on a 9-point scale.

That, said Prinyawiwatkul, compares favorably with typical responses. “A score of 6.2 is good,” he said. “It’s almost impossible to get an 8 or 9.”

Consumers buy based on taste, texture and price, Prinyawiwatkul said. With so many similar products in the marketplace, why wouldn’t consumers buy those with low sodium?

To find out how consumers perceive the positives and negatives of sodium reduction, researcher Wisdom Wardy is measuring how tasters react emotionally and perceive low-sodium products in terms of taste and flavor versus health benefits.

“We have discovered that consumers’ preference for low- and reduced-sodium products improves when they learn of the health benefits they provide,” Prinyawiwatkul said.

The AgCenter research in food preferences got a boost recently with the opening of the new Animal and Food Sciences Laboratories Building on the LSU campus in Baton Rouge.

The sensory laboratory includes space for focus group sessions and private booths where people can taste and respond to questions about foods they sample.

“People learn to like food when they’re growing up,” Prinyawiwatkul said. “We want to find out how we can change those likes to move people to more healthful foods.”

Rick Bogren