Pourable and pumpable, viscous sweeteners are plant-derived liquids that bakers use to not only sweeten products but also add color, flavor and even nutrition. They are appreciated for their ability to bind ingredients and moisture, too. Some of them are minimally processed extracts, such as agave nectar and maple syrup, while others are produced commercially with assistance from acids, enzymes and/or heat. Think corn syrup and molasses. Concentrated fruit slurries also qualify as viscous sweeteners, as does honey.
Those with a healthful natural halo provide permission for consumers to enjoy a sweet treat. Economical options make baked foods affordable, often extending product shelf life and thus reducing waste.
Bakers value the ease of working with liquid sweeteners, as they can be metered and dispensed for quick dissolution in batter and dough. They are also more sanitary than their dry counterparts, as particles do not linger in the air.
“From a processing standpoint, viscous sweeteners can be easily incorporated into formulations and provide a smooth, homogenous texture in comparison to granulated sweeteners,” said Tom Sanders, global applications manager, ASR Group-DFI Specialty Ingredients.
The most cost-effective options tend to be flavorless and colorless with their primary purpose to provide sweetness, humectancy or both. Examples include corn syrup, high-fructose corn syrup (HFCS) and invert sugar. Others are more complex, thereby contributing to the sensory profile of the product.
Chemical compositions
Sucrose, also known as table sugar, is the base by which various ingredients are compared in terms of relative sweetness. Sucrose has a value of 1.0. It is a disaccharide of glucose, also known as dextrose, which has a sweetness of 0.7, and fructose with a sweetness of 1.2 to 1.8. Therefore, viscous sweeteners vary in relative sweetness based on their composition.
They also differ in their ability to brown through the Maillard reaction. This is a function of the presence of reducing sugars and is measured by dextrose equivalent (DE). The DE may also be an indicator of sweetness for ingredients that have a high DE value being sweeter than those with a lower value.
“Depending on the makeup of the liquid sweetener, it can either help or hinder the browning of the finished product,” said Tim Christensen, research and development, bakery applications, Cargill. “Both agave and honey, for example, contain reducing sugars. Some of these are simple sugars that can caramelize at lower temperatures, further contributing to crust color. In contrast, regular corn syrup contains dextrins, which do not brown as easily as some sugars.”
The buzz in bakery
Honey is a viscous sweetener that carries unique advantages ranging from flavor to functionality to marketability, according to Catherine Barry, director of marketing, National Honey Board. It is composed of fructose and glucose, making it up to 50% sweeter than sugar. This may allow a product developer to reduce the overall amount of sweetener ingredients used in a formula.
“The complex nature of honey gives it a natural dynamic you can’t find in other sweeteners,” Ms. Barry said. “Honey may seem simple on the surface, but if you analyze it, you’ll find it has more than 180 components including all-natural minerals, antioxidants, vitamins and prebiotics, as well as a host of carbohydrates and acids that give honey its complex flavor profile.”
Honey lends depth and complex flavor profiles to baked foods. It also is the only sweetener with a vast array of flavor profiles and varietals, all of which are naturally developed based on a honeybee’s diet.
“Monofloral honeys, such as orange blossom, buckwheat or watermelon, give bakers the ability to impart specific flavor profiles on their finished bakery foods,” Ms. Barry explained. “In monofloral varietals, honeybees predominantly visit one type of plant, and the nectar they pull from the flowers imparts a unique color, flavor and aroma on the honey. There are more than 3,000 varietals of honey worldwide.”
In addition to its flavor and functionality, honey’s key benefits include its lack of processing. Most natural sweeteners have been significantly manipulated using extreme heat, chemicals or machines to turn leaves, fruit and sap into powders or concentrated syrups.
“In contrast, honey is just honey,” Ms. Barry said. “Honeybees do all the heavy lifting, and beekeepers take the excess honey and extract it by removing the wax caps with a heated knife and spinning the honey to separate it from the comb.”
Most people think of sweetness when they think of honey, but there is also a tartness in the ingredient’s acidity. This profile balances flavors in baked foods without overwhelming sweetness. The acidity (average pH 3.91) also helps inhibit mold growth.
“Honey’s fructose content helps clean label breads hold in moisture and naturally extends shelf life. This reduces dryness and crumbliness of baked foods, making for a more acceptable finished product,” Ms. Barry said. It’s an amazing binder, holding together bars and bakery foods with a significant amount of inclusions. There is a reason so many fruit-, nut- and seed-dense bars contain honey.”
Like most sugar compounds, honey caramelizes during baking and contributes a desirable golden color to products.
“However, since honey’s main sugars are glucose and fructose, the Maillard reaction triggered by honey will be sped up,” Ms. Barry explained. “This allows bakers to lower their oven temperature or bake time and still maintain a quality color through their bake.”
Converting juices into syrups
While honey may be considered the most minimally processed viscous sweetener, others come close. These are juices extracted directly from plants and simply purified, heated, filtered and sometimes reduced.
Agave nectar, also called agave syrup, is the naturally sweet juice extracted from the agave cactus plant. It is about 1.4 to 1.6-times sweeter than sucrose with the same 4 calories per gram. The juice is a concentrated source of inulin, a dietary fiber that is not sweet by nature but, when heated, gets hydrolyzed into fructose.
Filtering determines the agave nectar’s flavor and color. The rule of thumb is that one cup of sugar can be replaced with ⅔ cup agave, along with a minor adjustment to added liquids. Depending on the application, agave nectar may add richness and enhance other flavors. Because fructose’s browning point is significantly lower than that of sugar, when working with agave nectar, baking times and temperatures are often reduced.
“Agave is less common in baked goods partly due to its premium price and strong browning effect when heated,” Mr. Sanders said. “But its high sweetness factor and clean label status makes it ideal for nutrition bars.”
Pure maple syrup is made by concentrating the slightly sweet sap of the sugar maple tree. The sap is simply boiled down into syrup. Color and flavor vary according to time of harvest. Light amber maple syrup, for example, is extracted early in the season and, as the name suggests, has a light golden amber color with mild maple flavor. As the harvest season progresses, the sap gets darker and more flavorful. It is the end-of-season syrups that are mostly used as commercial ingredients. These full-bodied syrups have intense maple flavor and a dark color.
Fruit syrups are another all-natural option. Prune juice concentrate, for example, is dark with a lightly caramelized flavor. It contains about 36% total sugars. More than half is glucose with the rest fructose and sorbitol.
“Just a small amount added to a reduced-fat and -sugar brownie recipe improves flavor and texture,” said Kate Leahy, spokesperson, Sunsweet Ingredients. “Prune juice concentrate may also help extend the shelf life a few days longer for baked goods designed for grab-and-go displays, in particular in gluten-free products. In gluten-free pumpkin bread, for example, the pumpkin and prune juice concentrate work together to enhance moisture and structure, eliminating the need for xanthan gum.”
Fresh plum concentrate is another option. It is a dark red syrup with a tart cherry flavor.
“It is a little higher in acid than prune juice concentrate (pH is 3.4-3.9) and not quite as sweet,” Ms. Leahy said. “Both can contribute to the Maillard reaction, which can be especially beneficial in baked goods such as gluten-free products that tend to have difficulty browning. Both concentrates also can add sheen to items such as sauces and fruit compotes, so making a switch to them from HFCS and other sweeteners will not cause a product to lose its luster.”
Carolina Innovative Food Ingredients uses the sweet potato to make natural viscous sweeteners. One ingredient is a cloudy sweet potato juice that adds flavor, color and a nutritional boost. There’s also a clarified version that is an alternative to HFCS and sugar.
This article is an excerpt from the June 2020 issue of Baking & Snack. To read the entire feature on sweeteners, click here