KANSAS CITY — Cut down on sugar. The 2015 installment of the Dietary Guidelines for Americans voiced the sour recommendation that sugar intake be limited to 10% or less of calories. The emphasis was on added sugars, not those inherent in foods, such as the lactose found in milk or the fructose in an apple.
In response, many bakers have made lowering added sugars a priority. This is not as easy as it sounds. Conventional sugar, also known as sucrose, is essential for baking. Not only does it add desirable sweetness, but because of its unique chemical nature, sugar also performs many other critical functions in baked goods. For example, in yeast-raised items, sugar fuels yeast fermentation. In some products, it affects the rate of starch gelatinization, which impacts shelf life, while in others, sugar participates in the Maillard reaction responsible for the development of desirable surface browning during baking and frying.
When reducing added sugars in baked goods, high-intensity sweeteners are often used in conjunction with traditional sweeteners and/or bulking agents to get the best sweetness profile along with the other desirable functionalities. High-intensity sweeteners are many times sweeter than sucrose, and thus, significantly smaller amounts are needed to achieve the same level of sweetness. The greatest challenge when working with high-intensity sweeteners in baked goods is to identify the right balance of ingredients to achieve desired sweetness while also providing necessary texture and mouthfeel.
“The decision tree can be complex when selecting a sweetening system,” said Thom King, president, Steviva Ingredients. “Each sweetener will have different physical, chemical and sweetening properties, so finished product attributes and ingredient functionality are important considerations.
The presence or absence of other ingredients can magnify or mute sweetener tendencies, according to Mr. King. “When certain sweeteners are used in tandem, their value exceeds their solo contribution,” he said. “Making the most of synergies optimizes flavor while lowering the use levels, ultimately reducing costs.”
Part of that decision tree includes finished product descriptors and label claims. Currently in the US, there are eight high-intensity sweeteners. Six of them — acesulfame potassium (ace-k), advantame, aspartame, neotame, saccharin and sucralose — are regulated by the Food and Drug Administration (FDA) as food additives and are considered to be artificial sweeteners. The others — monk fruit and stevia — are regulated as Generally Recognized as Safe (GRAS) ingredients and considered to be natural sweeteners.
All but one of these high-intensity sweeteners are further classified as non-nutritive, meaning they are very low in calories or contain none at all. The exception is aspartame, which does contain calories. Because aspartame is about 200 times sweeter than sucrose, not much is needed to achieve desired sweetness, and therefore, it typically contributes negligible calories to a formulation.
“Since its introduction more than 25 years ago, aspartame has revolutionized the food industry due to its clean, sweet taste that is closer to the taste of sugar than any other high-intensity sweetener,” said Ihab Bishay, senior director, applications development, Ajinomoto North America, Inc. “Aspartame is made up of components naturally occurring in common foods, such as dairy products, grains, meats and juices, and is metabolized by the body.”
Because aspartame is not heat-stable, its use in baked goods is limited to components added after baking or frying, such as frostings, fillings and glazes.
All other artificial sweeteners are heat-stable and can be used in baking and frying. Saccharin has been around the longest. Discovered in 1879, saccharin is 200 to 700 times sweeter than sucrose. In the early 1970s, saccharin was linked with the development of cancer in laboratory rats, which led to placement of a mandatory warning label on saccharin-containing products. Since then, more than 30 human studies demonstrated that the results found in rats were irrelevant to humans and that saccharin is safe for human consumption. In 2000, the National Toxicology Program of the National Institutes of Health concluded that saccharin should be removed from the list of potential carcinogens. Products containing saccharin no longer have to carry the warning label.
Ace-K is about 200 times sweeter than sugar and is often used in combination with sucralose, which is about 600 times sweeter than sugar. Blends of the two are available for ease-of-use in the baking environment. A blend of ace-K, sucralose and natural flavor can replace the sugar in fruit preps used in some baked goods. It can cut calories in half and reduce added sugars by more than two-thirds.
The two most recently approved additives — advantame and neotame — have the greatest sweetness intensity. Approved in 2002, neotame is approximately 7,000 to 13,000 times sweeter than sugar. Advantame was approved in 2014 and is almost 20,000 times sweeter than sugar.
“Advantame also has a clean, sweet taste with no off-tastes,” Mr. Bishay said. Plus, it enhances many flavors, such as vanilla, chocolate and fruit, which are commonly used in bakery products. “It can be blended with sugar or high-fructose corn syrup for partial sugar replacement to reduce cost and calories or with other high-intensity sweeteners.”
The two GRAS high-intensity sweeteners — stevia and monk fruit — are the ones many bakers are pursuing because of their natural, clean-label reputation. Both are based on plant extracts and are heat stable.
Stevia-based sweeteners are the more widely known of the two. Based on extracts (steviol glycosides) from leaves of the Stevia rebaudina plant, stevia-based sweeteners are 200 to 400 times sweeter than sugar. FDA has received many GRAS notifications for use of high-purity (95% minimum purity) steviol glycosides including rebaudioside A (also known as reb A), stevioside, rebaudioside D and steviol glycoside mixture preparations with reb A and/or stevioside as predominant components. FDA has not questioned any of the notifiers’ GRAS determinations. The use of stevia leaf and crude stevia extracts is not considered GRAS, and importation into the US is not permitted for use as sweeteners.
The other GRAS high-intensity sweetener is monk fruit, also known as luo han guo (Siraitia grosvenorii). This small, vine-grown, subtropical fruit gets its zero-calorie sweetness from naturally occurring antioxidants called mogrosides, which are up to 300 times sweeter than sugar.
Thaumatin is a plant extract recognized for its taste-enhancement properties. Used by West Africans for hundreds of years to sweeten corn breads, sour fruits and also to make palm wine palatable, thaumatin is a natural protein that is water-extracted from the katemfe fruit (Thaumatococcus daniellii) harvested from the West African rainforests, rendering it a natural ingredient.
In the 1970s, great emphasis was placed on thaumatin’s sweetening properties, and for some time, this defined its regulatory and marketing path. Today, thaumatin has GRAS status as a flavor enhancer, but does not have approval as a sweetener. It appears on ingredient statements as “natural flavor.”
Being approximately 2,000 to 3,000 times sweeter than sucrose, this natural flavor is water soluble and stable to heat and pH, making it useful in most applications. It is a protein and, therefore, contains 4 Cal per g, but because of its intense sweetness, usage levels are very low; thus, it contributes negligible calories.
Thaumatin is known to mask off-tastes associated with some artificial sweeteners. It also enhances flavors and improves the taste of sugar and salt replacers. It combines well with other sweeteners, helping extend and enhance the flavor profile and length of delivery.
The most recent sweetener to enter the marketplace is allulose, an almost no-calorie sugar monosaccharide that exists in nature. Having received GRAS status in 2015, the ingredient provides the mouthfeel of table sugar, along with about 70% of its sweetness; thus, it is not a high-intensity sweetener. Rather, it is considered a low-calorie sugar because it provides 90% fewer calories than full-caloric sugar.
“Allulose may not be a high-intensity sweetener, but it is a very good match with many of them in the market,” said Yuma Tani, deputy manager of R&D, Matsutani. “It is a monosaccharide characterized as a ‘rare sugar’ and contains just 0.2 Cal per g, delivering true sugar flavor with no aftertaste. Bakers can formulate with allulose to create low-calorie bakery products without the drawbacks of long-lasting aftertaste and synthetic or chemical perception.”
As a substance that exists in nature, allulose is found in small quantities in jackfruit, figs, raisins and wheat and is naturally present in small quantities in foods such as caramel sauce, maple syrup and brown sugar. Allulose has several beneficial health characteristics. When consumed, the body absorbs the allulose but does not metabolize it; therefore, it is not converted to glucose, so its calories are not available to the body, making it practically calorie-free. Unlike other caloric sugars, allulose has no impact on blood glucose or insulin levels.
Erythritol and maltitol are popular sugar alcohols used in baked goods. Because these sweeteners contain bulk, they are often used in combination with high-intensity sweeteners to achieve the right texture in baked goods.
Erythritol has about 60 to 70% the sweetening power of sucrose with 0 Cal per g. It occurs naturally in fruits such as pears, melons and grapes, as well as mushrooms and fermentation-derived foods such as wine, soy sauce and cheese. Since 2001, it has been considered GRAS, making it an attractive bulk sweetener in baked goods sporting natural claims.
Maltitol, on the other hand, is sweeter (about 90% sweetness of sugar) while also containing calories (2.1 Cal per g). Many of its characteristics are similar to sucrose, making it popular in baked goods.
Bakers must never forget that no single ingredient can replace the sweetness and the many functions of sugar in baked goods. When working with high-intensity sweeteners, it is critical that a baker recognize the functions sugar performed in a system and identify a suitable replacement.
For example, sugar slows down foaming thus stabilizing meringue by protecting the egg whites from being overbeaten. Once the foam is formed, sugar prevents its collapse by providing support to the air bubbles. Another example is that sugar keeps baked goods moist by bonding with water molecules. When tying up water, sugar prevents the proteins and starches in the system from binding with water, which could create a tough texture. Thus, sugar creates tenderness in baked goods. In both of these situations, hydrocolloids can typically assist.
In some systems, sugar adds crunch. For example, moisture evaporates from the surface of a product as it bakes, allowing dissolved sugars to re-crystallize. This creates the crunchy, sweet crust associated with brownies and muffins. Sometimes, an egg wash can assist with providing crunch and, depending on the application, also contribute desirable brown color.
Knowing sugar’s functions allows formulators to blend high-intensity sweeteners and other ingredients to achieve desired taste and physical attributes.
“Our most successful sweetening system for baked goods is a non-GMO crystalline fructose and stevia blend,” Mr. King said. “This blend delivers up to a 70% sugar reduction. It participates in the Maillard reaction, thus facilitating browning and caramelization. It also works with yeasts.
“Additionally, we have a stevia-fortified agave nectar that is a plug-in system designed to replace 42 DE high-fructose corn syrup,” Mr. King continued. “This works very well in pies, including most fruit varieties, as well as pecan, sweet potato and pumpkin. The solution delivers a 75% clean-label sugar reduction.”
Both of these systems rely on nutritive sweeteners (crystalline fructose or agave nectar) to provide sugar functionality beyond sweetness. That’s what the stevia is for.
“For deeper clean-label sugar reduction, we have a stevia and erythritol blend and a stevia, monk fruit and erythritol blend,” Mr. King said. “Both of these offer 95% clean-label sugar reduction. Because they do not ferment or participate in the Maillard reaction, they are best used in baked products such as cookies, snaps and cakes, but in certain application, browning can still be achieved with an egg wash.”
Both ingredients are also available in a format similar to confectionary sugar. This renders them suitable for use in fillings, frostings and fondants.
In conclusion, Mr. Bishay said, “High-intensity sweeteners will become increasingly important in bakery products to replace the added sugar for an increasingly health-conscience consumer, as well help improve the taste profile of some of the newer ancient grain-based and newer grain-based-products that are gaining traction with consumers.”
Still sweet, still popular
Honey, mankind’s first sweetener, continues to exert its sweet power today, with 93% of consumers viewing it as a natural sweetener and 43% actively seeking food products made with it, according to an independent study of consumers nationwide, commissioned by the National Honey Board (NHB).
“This study confirmed our assumptions that consumers love honey,” said Catherine Barry, NHB’s director of marketing. “Many consumers think the ingredient is natural, look for it on labels and pay more for a product that is made with honey.”
Another key finding was that nearly 60% of consumers would pay 5% more for bread primarily sweetened with honey. About half would pay that upcharge for food bars similarly sweetened.