Field Notes

Study Suggests Sweet Taste Perception Changes as Children Develop

Compared with adults, children and adolescents are less sensitive to the sweet taste and need 40% more sucrose in a solution for them to detect the taste of sugar, according to a new study.

Along with higher taste detection thresholds, both children and adolescents prefer significantly more concentrated levels of sweetness than adults.

“Both of these dimensions of sweet-taste perception—sensitivity and preference—undergo distinct developmental trajectories from childhood to adulthood,” says M. Yanina Pepino, PhD, a professor of food science and human nutrition at the University of Illinois, Urbana-Champaign, who cowrote the study. “However, they did so independently, and we found no association between the two.”

The study included 108 children, 172 adolescents, and 205 adults, who ranged in age from 7 to 67. The National Institutes of Health and the American Diabetes Association supported the research, conducted at the Monell Chemical Senses Center in Philadelphia and Washington University in St. Louis.

Julie A. Mennella, PhD, of the Monell Center cowrote the study, published in the journal Nutrients.

The researchers gave participants different pairs of sugar-water concentrations to taste and measured both the concentration that participants preferred and the lowest concentration at which they could detect the taste of sugar.

“While children’s lower sensitivity required higher sucrose concentrations for them to detect the taste, participants’ sweet-taste sensitivity did not predict the level of sweetness they preferred,” Mennella says.

“To illustrate these age-related differences in taste sensitivity, we estimated the number of 8-oz glasses of water in which 4 g of sucrose—the equivalent of one sugar cube—could be dissolved and participants in each age group could start detecting the sweet taste.”

For example, children and adolescents’ lower sensitivity means they would only be able to detect the taste if the sugar cube were dissolved in five glasses—40 oz—of water, but adults would be able to detect it in a less concentrated solution of seven glasses—56 oz—of water.

Consistent with previous studies, the researchers found that children preferred more intense sweetness than did adults.

Adults favored levels of sweetness similar to a typical cola soft drink, which contains the equivalent of about eight sugar cubes in an 8-oz glass of water, Mennella says. Children and adolescents preferred a 50% higher sucrose concentration—equivalent to about 12 sugar cubes in 8 oz of water.

The study built upon and combined data from the researchers’ previous research.

“Using the same sensory evaluation methods we used here to measure sucrose preferences, we found previously that the binding potential of dopamine receptors in the striatum, a brain area that encodes the value of rewards, decreased with age—and predicted, independently of age, the most preferred sucrose concentration in healthy young adults,” Pepino says.

The researchers hypothesized that the changes in sucrose taste sensitivity and preferences that occur during adolescence may result from distinct developmental trajectories with different underlying mechanisms.

“For example, developmental changes in taste sensitivity may be secondary to changes in the anatomy of the mouth and saliva composition, whereas changes in sweet-taste preferences may be the consequences of changes in the activity and morphology of the brain reward system,” Pepino says.

— Source: University of Illinois at Urbana-Champaign

 

Cooking Red Meat at High Temperatures May Impact Heart Disease

The world’s best chefs have taught us how to barbeque, grill, and pan-fry a steak to perfection. But while the experts may be seeking that extra flavor, new research from the University of South Australia (UniSA) suggests high-heat caramelization could be bad for our health.

Conducted in partnership with the Gyeongsang National University in South Korea, the study found that consuming red and processed meat increased a protein compound that may increase the risk of heart disease, stroke, and complications in diabetes.

UniSA researcher Permal Deo, PhD, says the research provides important dietary insights for people at risk of such degenerative diseases.

“When red meat is seared at high temperatures, such as grilling, roasting or frying, it creates compounds called advanced glycation end products—or AGEs—which, when consumed, can accumulate in your body and interfere with normal cell functions,” Deo says.

“Consumption of high-AGE foods can increase our total daily AGE intake by 25%, with higher levels contributing to vascular and myocardial stiffening, inflammation, and oxidative stress—all signs of degenerative disease.”

Published in Nutrients, the study tested the impacts of two diets—one high in red meat and processed grains and the other high in whole grains, dairy, nuts, and legumes, and white meat using steaming, boiling, stewing, and poaching cooking methods.

It found that the diet high in red meat significantly increased AGE levels in blood, suggesting it may contribute to disease progression. In Australia, CVD represents 1 in 5 of all deaths.

Coresearcher Peter Clifton, MBBS, PhD, MRCP, FRACP, an adjunct research professor at UniSA, says while there are still questions about how dietary AGEs are linked to chronic disease, this research shows that eating red meat will alter AGE levels.

“The message is pretty clear: If we want to reduce heart disease risk, we need to cut back on how much red meat we eat or be more considered about how we cook it.

“Frying, grilling, and searing may be the preferred cooking methods of top chefs, but this might not be the best choice for people looking to cut their risk of disease.

“If you want to reduce your risk of excess AGEs, then slow cooked meals could be a better option for long-term health.”

— Source: University of South Australia