Tagatose is a naturally occurring rare sugar that has garnered interest as a sweetener. It offers a unique appeal in the food industry due to its taste profile, which closely mimics that of sucrose, or common table sugar. This makes tagatose a compelling option for those seeking sugar alternatives that do not compromise on sensory experience.
Understanding Tagatose
Tagatose is classified as a monosaccharide, a simple sugar. It is found in small quantities in nature, such as in certain dairy products like cheese, yogurt, and sterilized powdered milk, and in some fruits like apples and oranges, but its natural abundance is limited.
Commercial production of tagatose typically involves an enzymatic conversion process starting from lactose. This industrial method allows for a more scalable and cost-effective supply. Tagatose appears as a white, crystalline, and virtually odorless solid. It possesses about 92% of the sweetness of sucrose, but delivers significantly fewer calories, approximately 1.5 kcal/g, which is about 38% of the caloric value of sucrose (4 kcal/g). Tagatose also exhibits high solubility in water and remains stable across a pH range of 2-7.
Health Aspects of Tagatose
Tagatose has a notably low glycemic index (GI) of 3, considerably lower than sucrose’s GI of 68. This minimal impact on blood sugar levels makes it a suitable sweetener for individuals managing blood glucose, helping prevent rapid spikes. Research indicates tagatose can also contribute to lowering HbA1c levels, a marker for long-term blood sugar control.
The sugar also functions as a prebiotic, meaning it supports the growth and activity of beneficial bacteria in the gut, such as Bifidobacteria and Lactobacilli. Only about 15-20% of ingested tagatose is absorbed in the small intestine, with the remaining 80-85% traveling to the colon where it is fermented by the gut microbiota. This fermentation process produces short-chain fatty acids, which play a role in maintaining gut health and supporting immune function.
Tagatose is considered non-cariogenic, meaning it does not contribute to tooth decay. It does not get readily fermented by cariogenic oral bacteria like Streptococcus mutans, which are known to cause dental caries. Studies suggest it can inhibit biofilm formation and reduce the activity of these bacteria, potentially improving oral health. Unlike traditional sugars, tagatose is metabolized differently in the body; only a small portion is absorbed and processed in the liver, similar to fructose but at a slower rate.
Using Tagatose
Tagatose finds diverse applications across the food and beverage industry, serving as a sweetener in baked goods, beverages, dairy products, and confectionery. Its ability to closely mimic sucrose in taste and texture makes it a versatile ingredient for product reformulation. In baking, tagatose offers functional properties beyond sweetness, promoting browning and caramelization, which are attributes often lacking in other sugar alternatives. It also helps in moisture retention, contributing to the freshness of baked goods.
While generally recognized as safe (GRAS) by the U.S. Food and Drug Administration (FDA) since 2001, and approved as a novel food ingredient in the European Union, consumption of tagatose at high levels can lead to potential side effects. Exceeding approximately 30 grams per serving may result in digestive discomforts such as bloating, gas, and a laxative effect. These symptoms are typically mild and temporary, and individuals may develop a tolerance with frequent consumption.