How to evaluate nutritive sweeteners for bakery and snack uses
June 22, 2012
by Laurie Gorton
What’s the deal with nutritive sweeteners? Food industry critics recently put intense scrutiny on foods containing sugar, yet consumers continue to seek them out. And every baker knows that without nutritive sweeteners, yeast would perform poorly, crusts would brown anemically, bread would stale quickly, cookies would go limp, and cakes would lack all taste appeal whatsoever.
Sweeteners earn their rightful place in baked foods not only for their sweet flavor but also for their ability to bulk, structure, brown, aerate, fuel and maintain the product’s moisture, shelf life and appeal. Through specification of nutritive sweeteners, the formulator can deal a winning or losing hand for the finished product. As Catherine Barry, director of marketing, National Honey Board, Firestone, CO, said, “When choosing a sweetener, bakers should always factor in flavor, functionality and consumer perceptions of the sweetener.”
Today, product developers can pick among many sweeteners. “Choice of nutritive sweetener is a complex subject,” observed Joe Hickenbottom, vice-president, sales and marketing, Malt Products Corp., Saddle Brook, NJ. “The formulator has to be specific about the baked item’s requirement. Is it a sweetener to support fermentation? Is it chosen for cost, for flavor? You must compare apples to apples.”
Dealing with goals
The term “nutritive sweetener” applies to sugars and carbohydrate syrups carrying 4 Cal per g and contributing a significant portion of a food’s energy value. Usage levels range from 2% in breads and 30% in cakes to 70% in icings (all percentages are on a formula weight basis). In contrast, high-intensity sweeteners weigh in at very low calorie count and minuscule usage level.
Flavor agent, yeast fuel, moisture guard, structure builder, crust browner — nutritive sweeteners play many roles. In any yeast-raised product, yeast fermentation depends on sugar for its fuel, whether naturally present or deliberately added. In chemically leavened cakes, sugar acts primarily as a sweetener. In both product types, it affects the rate of starch gelatinization, which improves shelf life, and it helps maintain moisture content. Sugar also participates in the Maillard reaction responsible for crust browning.
Deciding among nutritive sweeteners requires an understanding of finished product goals. “Should the sweetener be in the formula just for flavor purposes, or can it be used to add textural benefits?” asked Brook Carson, technical product manager, ADM, Overland Park, KS. “Varying particle size and shape can affect the finished product texture. Sweeteners can also be chosen based on the desired flavor profile.”
Selection should encompass the whole formulation, according to Judie Giebel, technical services representative and AIB Certified Baker, Briess Malt & Ingredients Co., Chilton, WI. “Bakers must consider all other ingredients being used in their formula,” she said. Will the sweetener boost flavor, or is it the structure, color or browning that is most important?
Function is often the determining factor. “You will need to decide which functionality you are trying to achieve,” said Stefanie Ringo, technical services lead, nutritive sweeteners, Cargill, Minneapolis, MN. “High-fructose corn syrup (HFCS) may be a good replacement for sugar while a blend of sugar and corn syrup may be more desirable in other applications.”
Practical considerations also involve bakery equipment. Ms. Carson explained, “If a plant is not set up for liquid sweeteners, dry sweeteners are a better choice.”
On the other hand, an automated large-scale bakery may find handling dry sucrose to be less cost-effective and more labor-intensive, suggested Eric Shinsato, technical sales support manager, Corn Products International, Westchester, IL. “Corn syrups can be delivered by tank truck or railcar, depending on volume requirements, and off-loaded into a bulk storage tank,” he said.
From there, an automated system controls the flow of the syrup to the mixing area. “If manually bag dumping dry sucrose, the product will need to weighed by scale or load cell,” Mr. Shinsato added. “There is also the cost of disposal of bags or totes as well as the labor to move and handle the product.”
Shuffling a change
Probably the biggest decisions about nutritive sweeteners today concern HFCS. When introduced in the 1980s, it quickly replaced nearly all sugar, liquid sucrose and invert syrup used for breadmaking. Recently, a number of outspoken food industry critics pushed to get rid of HFCS, and many bakers returned to sucrose.
But now a sweetener that many tossed on the discard pile is getting picked up and played again. “I get the impression from talking to people in the baking industry that there is a move back to HFCS from sucrose,” Mr. Hickenbottom said, “but the decisions are being made with little hoopla.
“Bakers recognize that there is no difference in functionality between these sweeteners in the baking process,” he added. “In formulation and performance, 42 or 55 HFCS compares equally with liquid sucrose; however, there is a huge cost difference with sucrose much higher in price than HFCS.”
Sanjiv Avashia, senior food scientist, Tate & Lyle, Inc., Decatur, IL, also reported some bakery customers are going back to corn syrups. He emphasized reasons for this choice go far beyond sweetness. Such functional aspects as solubility, sweetness profile, humectancy, browning action — all can be important aspects, depending on the product being made. “It’s not just the sweetness that corn syrup brings,” he said.
The sucrose-HFCS hand
Formulators interested in swapping sucrose for HFCS must consider several performance factors. HFCS is roughly 80% water, while granular sucrose contains essentially none. Liquid sugar has lower solids content than HFCS, and the volume added to a batch would need to be increased.
“One will see differences in crust color of breads formulated with sucrose,” Ms. Ringo said. “The lighter-color crust may also not have some of the flavors associated with the color compound formed from dextrose and fructose in the oven.”
Depending on the application, sucrose and HFCS differ in several ways. Mr. Shinsato explained, “These may include spread and texture in soft cookies, sucrose crystallization in fillings and glazes, and browning and shelf life in other baked foods. If HFCS is replaced in bread or other yeast doughs, then the rate of fermentation may be reduced or prolonged over time. For processing, the order in which ingredients are added may need to be adjusted if additional water is added.”
Sucrose has a tendency to crystalize under low-moisture conditions, and the finished product may stale faster, according to Mr. Avashia.
Food safety concerns enter the picture, too. “Sucrose is much more sensitive to microbial contamination than corn syrup and must be handled accordingly,” Ms. Ringo said. Water activity in the finished product can increase because of the solids difference. “Corn syrup may improve the shelf life of certain baked goods while sugar does not provide this trait, so this should be taken into consideration as well,” she added.
Labeling also can be an issue. “A formulator may have specific requirements related to caloric contribution, natural claims or limiting allergens,” Ms. Carson noted.
Ante up function
Moving beyond the sucrose-HFCS faceoff, bakers can bid their sweetener hands many ways.
Look at the specific needs of the end product, Ms. Ringo advised. “Brownies and cakes require a fine, uniform granulation if using dry sweeteners to ensure proper structure setting and rising,” she said. “In some baked products, the crystalline texture provided by sugar can be an advantage. In other products, minimizing or eliminating crystallization through use of corn syrups may provide the desired texture.” Corn syrups are often blended with sugar to achieve specific effects.
Also, mixing sucrose with crystalline fructose produces a synergistic effect, according to Mr. Avashia. “Together, they make products sweeter than each would separately. This allows you to reduce total sweetener solids, thus cutting calories without impact on the perception of sweetness.”
Browning presents another interesting option. “The reducing properties of dextrose can enhance browning,” Mr. Shinsato said. “It can also provide humectant properties to improve shelf life. Corn syrups impart a soft or chewy texture as well as humectancy.”
Fermentability will be key for yeast-raised products. “You have to consider proof times, too, when you choose among sweeteners,” Mr. Hickenbottom said.
Still, flavor can be the most important function, and it differs from sweetness. “Some sweeteners carry a flavor while others are bland, and they all deliver varying degrees of sweetness,” Ms. Giebel said. “For example, HFCS has an intense sweetness and no flavor. Tapioca syrup, meanwhile, carries the same bland flavor but lower sweetness levels depending upon its DE. As a result, HFCS could be used at a lower level than standard sugar, and tapioca syrup would need to be used at a higher volume to attain the correct level of sweetness.”
Flavor masking is another aspect of sweeteners that covers off-flavors of vitamins, minerals or other fortification materials. Ms. Giebel explained that brown rice syrup has a slight butterscotch flavor that complements baked foods, while malt extract carries a strong, almost molasses-like taste that can mask other unpleasant flavors.
The specs for nutritive sweeteners provide valuable guidance for optimizing their use. This is especially true for dextrose equivalency, usually expressed as DE, and granulation size.
The DE of a sweetener syrup indicates the percentage of native starch broken down by processing. The greater the DE number, the more dextrose the syrup contains, and the sweeter it tastes. Common practice describes corn syrups as 27, 42, 62, 70 or 95 DE. This numbering carries over to HFCS, but its numbers stand for the percentage of fructose. Thus, 42 HFCS contains 42% fructose. HFCS also comes in 55 and 90% fructose formats. Sucrose, a natural disaccharide, contains one unit of fructose and one of dextrose.
“A 62-DE syrup is the sweetest likely to be used in baked foods,” Mr. Hickenbottom said, “but at that level, the baker should be stepping up to HFCS.”
Low-DE syrups, although supplying useful adhesion for gluten-free breads, are not common in more usual bread styles because “you could end up with a brick instead of a loaf,” said Jim Mitchell, director of R&D, Ciranda Organic Ingredients, Hudson, WI. The crust won’t brown properly, and the product will dry out faster.
At low and mid-range conversions, much more of the starch source’s attributes come through, according to Mr. Mitchell. “For example, low-DE corn syrup is more viscous than low-DE tapioca syrup. Tapioca has more film-forming characteristics, and so a low-DE tapioca syrup will produce a tack-free texture compared with a low-DE corn syrup.”
If more sweetness and less structure are needed, then a higher DE level is the answer, according to Ms. Giebel, but if viscosity and texture are required, then lower DE works best.
Summarizing DE’s impact, Mr. Shinsato observed that it affects three important baking properties: sweetness, browning and humectancy. “As the DE of the sweetener increases, all three of these properties increase,” he said. “The proper choice of DE will help balance these characteristics to give the desired result in the finished product.”
With dry sweeteners, granulation is generally not a factor when the sweetener serves primarily as a fuel for yeast fermentation. But in cakes, cookies and similar applications, particle size is of vital importance. “Granulation will affect the overall structure and tenderness of the finished product,” Ms. Giebel said. “Finer granulation results in a smoother, softer, more tender product than a coarse grind.”
Ideally, particle size should be similar to that of other dry ingredients such as flour, Mr. Shinsato advised. Such sizing maintains a homogenous blend without segregation. Typical bakery mixes use standard-grade dextrose and spray-dried maltodextrins and corn syrup solids.
Differentiating 6X powdered sugar from the 10X style isn’t easily done by eye, but many experienced bakers can distinguish them by feel. Granulation size makes a big difference to the finished product. While the coarser 6X powdered sugar yields very satisfactory flat and creme-style icings, 10X sugar makes smoother and more tender icings that approach the character of fondants.
Cane, beet and corn aren’t the baker’s only sources of nutritive sweeteners; most grains can be converted into syrups, with malted barley extract one of the earliest sweeteners used by bakers. These grain syrups contribute unique flavors, colors and sweetener profiles as well as functional differences. For example, many contain maltose, which beneficially influences crystallization to improve the quality of frozen doughs as well as frozen finished products.
Malt extracts range in color from light golden to amber to intense black and are half as sweet as sugar. Their use, Ms. Giebel explained, is mainly for browning, flavor and color and are best combined with other sweeteners for sweetness. “Dark malt extracts work great in spice cake, gingerbreads and dark breads,” she said. The darker extracts can replace certain caramel colors while the lighter styles are well-suited to pizza crusts, flatbreads, cookies, bagels and whole grain products to add flavor to mask the whole grain tannins.
Brown rice syrup, made from long-grain brown rice by a natural process, will replace any sweetener of the same DE. Lower DE styles work well as binders in bars and granolas while higher DE rice syrups give sweetness and humectancy, Ms. Giebel explained. Briess produces sorghum syrup from the grain, not the cane, of the sorghum plant, and the syrup contributes flavor and good browning properties to gluten-free baked goods.
Tapioca syrup offers clean, bland flavor and can replace any sweetener with the same DE on a 1:1 basis. “Tapioca syrup is used where you want just sweetness or viscosity but no flavor,” Ms. Giebel explained. Because tapioca is traditionally cultivated, it is also non-GM, a factor of importance in certain formulations and markets.
“When moving from corn syrup, or more specifically from HFCS, you may want to consider agave syrup,” Mr. Mitchell advised. “It can replace HFCS on a straight 1:1 basis, and agave is actually higher in fructose than HFCS. Or you could use a special tapioca fructose syrup.”
It’s just a drop-in change to substitute organic nutritive sweeteners for non-organic styles, as long as the formulator takes into account a few differences, according to Mr. Mitchell. “It is hard to find a perfectly white organic sugar,” he said. Many have a gold tone and a more pronounced flavor, which can be advantages in certain applications.
Win the game
Whether the project involves developing a new product or evaluating a current one, a good look at its nutritive sweetener will be well worth the effort. Cost savings could be one result, but new market opportunities can also come into play.
For example, consumers are shifting their attention away from HFCS and toward claims of “less sugar” or “no sugar added.” When reformulating, consider eliminating sweeteners that don’t provide necessary functionality, Mr. Hickenbottom advised. “You can readily eliminate those not needed and limit your use to one or two, thus reducing the overall need for a number of sweeteners in the product,” he said.
There are certainly enough cards in the nutritive sweetener deck to deal a new hand and play a more profitable baked foods game.