Study shows techniques for reducing sugar content in dairy products show promise
According to the IDFA, dairy sales gross more than $125bn per year, however, consumers also demand healthier, low-calorie products that taste the same as their higher calorie counterparts.
In the Journal of Dairy Science report, researchers reviewed the options available to the dairy industry to reduce sugar in products such as ice cream, yogurt and flavored milk without sacrificing flavor.
Lead investigator MaryAnne Drake, PhD, William Neal Reynolds Distinguished Professor, at the Department of Food, Bioprocessing, and Nutrition Sciences at the research center, said dairy foods represent a large market.
"The dilemma of how to reduce sugar content without sacrificing flavor and negatively affecting product sales is challenging, as sugar plays an important role in dairy foods, not only in flavor, but also in texture, color and viscosity,” Drake said.
“Replacing sugar can have negative effects, making substitution inherently difficult."
Dairy products can be high in unwanted added sugar. Some of the standard processes for developing healthier food products, by reducing fat, sugar, and salt, may result in an unacceptable flavor. Sweet taste perception can also be affected by texture of the food matrix and the presence of fat.
Other sugar reduction techniques include hydrolysis of lactose, ultrafiltration and direct reduction.
Ice cream is one of the most heavily consumed dairy products in the world. To achieve its sweetness, 10 to 14% sugar needs to be added. Studies have shown reduced sugar and reduced fat products, such as ice cream, show a higher propensity for a bitter aftertaste and a lower intensity of creaminess. Among the promising options the researchers found were:
Calorie-reduced ice creams sweetened with sorbitol and sucralose were most accepted compared with other "light" vanilla ice creams or ice cream with a minimum reduction of 25% of the total energy, sugar or lipid.
Erythritol and lactitol are sugar alcohols that have been used to create low-calorie ice cream. Erythritol is more commonly used for sugar reduction in ice cream because it provides volume and texture, and is only a fraction of the calories in sucrose.
Chocolate-flavored ice creams are typically formulated with higher sugar content to decrease the bitterness associated with cocoa. When the sugar is reduced, not only does the ice cream taste more bitter, but it also tastes less ‘chocolatey.’
One study said marketing sugar-reduced chocolate ice cream to dark chocolate lovers could be a successful strategy, as they already tolerate substantially higher levels of bitterness.
Frozen yogurt is often viewed as a healthy alternative to ice cream because of its lower fat content and the presence of lactic acid bacteria, even when frozen, but the sugar content is typically the same as regular ice cream. A study of frozen yogurt determined that substituting inulin and isomalt for sugar and fat led to a similar sweetness and a reduction in fat with no added sugar.
While yogurt is generally recognized as healthy, it is usually sweetened with sugar to increase palatability. Several studies have reported that liking yogurt is influenced by texture, aroma and taste, and that sweetness is an important component.
Several studies found sweetener blends of non-nutritive sweeteners have been successful in reducing sugar content of yogurt.
One reported it was possible to produce a probiotic yogurt successfully using sweeteners without affecting the viability of the probiotic microorganisms. The addition of non-nutritive sweeteners did not negatively affect the yogurt-making process because the sweeteners did not break down over time.
Flavored milk is popular among children and adults, and studies have shown flavored milk increases milk consumption. Chocolate milk, the most popular flavor, typically has higher sugar content and is therefore a frequent target for sugar reduction.
However, the researchers said, reducing sugar in chocolate milk is quite costly and many school directors choose the higher sugar alternative to reduce cost or choose to eliminate chocolate milk entirely. There have been several studies into alternative ways of reducing sugar calories in chocolate milk with some contradictory results.
One study showed withdrawing a chocolate milk option meant that three or four additional foods needed to be added into the diet to replace the nutrients from milk, adding additional calories and cost. Therefore, sugar-reduced chocolate milk should be considered the cheaper alternative.
In another study, parents preferred natural non-nutritive sweeteners over nutritive sweeteners as the sweetener source in chocolate milk.
Some studies found added sugar could be directly reduced in chocolate milk and still be accepted by children and adults if it did not exceed 30%.
Overall, the most successful techniques for sugar reduction in dairy foods involve replacing sugar with non-nutritive sweeteners, whether natural or artificial, because these provide the sweet taste desired by consumers without added calories. Direct reduction of sugar and lactose hydrolysis methods also show promise.
"Understanding current sugar-reduction techniques, research, and consumer response to sugar reduction in dairy products is important for dairy manufacturers in order to design and produce sugar-reduced products," Drake said.
"Sugar reduction is an inherently difficult task due to the many functions of sugar in food products, but progress is being made in developing products acceptable to consumers.”
Source: Journal of Dairy Science
Invited review: Sugar reduction in dairy products
H.R. McCain, S. Kaliappan, M.A. Drake