CHICAGO — The term “retronasal,” though not commonly known, may play a role in sugar reduction. Retronasal may occur while people are consuming products, said Alex Woo, Ph.D., chief executive officer of W2O Food Innovation. Aromas are sucked backward into the nose, and this retronasal sweet aroma increases the sweet perception in the mouth.

A speaker at the Institute of Food Technologists’ Wellness 2014 in Chicago March 20, Dr. Woo gave retronasal as one example of sweetness modulation, or finding ways to make sweeteners taste sweeter in products. In sweetness modulation, formulators might take a product that is 6% sugar and make it taste like it was 12% sugar, he said. The achievement thus could allow for a 50% sugar reduction in the product.

He gave several sweetness modulation examples involving congruent flavors. A strawberry aroma may make people think the product is sweeter. A tomato aroma may fool a person’s brain into thinking the tomato has more sugar than it actually does, Dr. Woo said.

Vanilla comes with a twist. In the United States people associate vanilla with sweetness, but in Japan people associate it with salty.

Temperature also may affect the sweetness of a product. Stevia is sweeter in cold water. In contrast, drinking hot water prior to eating dark chocolate makes the chocolate taste sweeter, Dr. Woo said.

With sight, people associate round shapes with sweetness, he said. Strawberry mousse may be perceived as sweeter when it sits on a white plate instead of a black plate. A red room and red fruit may make whiskey taste sweeter, Dr. Woo said. With sound, hearing higher pitches such as those from a piano may make a product taste sweeter. High-pitched sounds thus pair well with sweet wine.

Besides explaining sweetness modulation, Dr. Woo also talked about several sweeteners.

The high-intensity sweetener stevia may be 200 to 400 times sweeter than sugar, he said, but it also may bring a bitter aftertaste. Monk fruit, another high-intensity sweetener, works well in blends. It has no bitterness, but it may be twice as weak as stevia in its ability to provide sweetness. It also may cost three times as much since monk fruit is grown only in China.

Dr. Woo said to be aware of monatin. The sweetener, an amino acid, is not approved for use in foods and beverages, but it may be in the future, he said. Monatin is 3,000 times sweeter than sugar.

Erythritol, a polyol, is non-caloric and cost-effective. It may be used in natural promotions although some people do not consider erythritol to be a clean label ingredient, Dr. Woo said.