A Spoonful of Sugar Helps the Savory Perform

A Spoonful of Sugar Helps
the Savory Perform
November 1995 -- Applications

By: Lynn A. Kuntz
Associate Editor*
*Editor since August 1996

  Sugar and other sweeteners come to mind readily when you think of confectionery products, cakes, beverages and many dairy products. But they also appear quite frequently in savory and non-sweet applications.

  While it's often fashionable to decry the use of sugars in so many processed foods, many product designers find that using sweeteners can provide a wide range of benefits in savory foods. The flavor - as well as the appearance, texture and even the shelf life - may benefit from a spoonful of sugar.

  The use of sweeteners in savory products appears to be on the rise, largely because of the changing tastes of the American consumer. In some products, a gradual shift has occurred; as manufacturers have added more sugar to certain products, people have begun to prefer them at higher sweetness levels.

  "Look at hot dogs, for example," points out Paul Maki, principal scientist, Griffith Laboratories, Alsip, IL. "If you go back 30 or 40 years you would never see sugars or any sweeteners in them. Now you have fairly high levels of corn syrup solids, dextrose or sorbitol to provide a certain level of sweetness which enhances the consumer acceptability of the product."

  Processed food applications are following culinary trends. Consumers are becoming more adventurous, trying and returning to different ethnic cuisines. Many of these combine sweet and savory elements. Italian-style spaghetti sauces traditionally use sugar to counterbalance the acidity of tomatoes. Asian has become a very popular profile, and it not only includes mainstream flavors like sweet and sour, but other sweet influences such as ginger, coconut milk and sweetened condiments, including tamari, plum sauce or peanut sauce. Caribbean jerk gives a sweet fruity flavor. Mexican fajitas have a sweet profile. Island cuisine can incorporate pineapple, coconut or banana. The trend toward fusion foods can combine a number of these sweet elements.

  In addition to the ethnic trends, fruit is becoming more common in savory applications. It can provide additional nutrients and flavor, as well as sweetness. Sometimes it can even provide functional benefits such as moisture retention. Applications can range from traditional products, such as pineapple with ham or fruit-based glazes, to more unusual concepts like fruit-flavored beers or even processed meats containing a substantial level of cherries. The sweetness levels of these types of products vary. Some require added sugars to enhance and amplify the flavor of the fruit; others rely solely on the natural sugars present in the fruit itself.

Tackling taste

  The most obvious result of adding sugars to foods is the effect on the product's taste. Sugar, in fact, provides the benchmark for the basic taste response referred to as sweet.

  Taste, as opposed to flavor, comprises the four primary tastes - sweet, salty, bitter and acidic - and may include other tastes such as savory umami. These are picked up by taste buds, or papillae, located in the mouth and on the tongue.

  While the mechanisms behind the sense of taste are not fully understood, research shows that many of the perceptions are related. The relationships vary with the tastes involved and the compounds that provide the stimulus. Eric Walters, Ph.D., a researcher at the Finch University of Health Science at the Chicago Medical School, North Chicago, IL, proposes that some molecules for sweet compounds and some for bitter compounds may compete for receptor sites, masking bitterness. Other relationships between sweetness and the other tastes have been observed, indicating that adding sugars to savory products changes their taste.

  Sweeteners can modify certain notes. They may take some of the sharpness or bite out of saltiness or mute the bitterness. Some metallic and bitter notes can be masked fairly effectively with sweet ingredients. Sweeteners can change something with a sour flavor, such as vinegar, into something that comes across as more pleasantly tart. Balanced properly, sweet and sour can create an agreeable flavor. They also act as a counterpoint to each other, which provides the basis for some of the most popular sauces and condiments in this country - ketchup and barbecue sauce, for example.

  "In some cases, if you have the balance right you might not even pick up a sweet flavor," says Keith Blowers, senior food technologist, McCormick Flavor Division, Hunt Valley, MD. "The actual sweetness threshold depends upon what other ingredients are in the product. For instance, the intent might be to project a fruity flavor, as in tomato sauce or a tropical marinade. Recently, there has been an increased interest in more complex flavor types, such as Asian, where fruit characterizes the overall flavor. Sometimes instead of sucrose I use fructose, which imparts a more fruity sweetness. Other alternatives to sucrose include corn syrup, honey, molasses and dextrose."

  The effect of sugar on other tastes provides an excellent product development tool. Sugar covers up undesirable notes and can enhance others. However, there is a lot of room for error for those who leave common sense by the door when using sweeteners to modify the flavor of foods.

  "One of the things sweeteners are used for is to mask salt perception," says Maki. "At another company, someone tried to increase the salt content on a sausage product - almost doubling it - by doubling the sweetener in the product."

  When this formulation was subjected to sensory analysis, half of the untrained panelists couldn't tell the difference in a triangle test. The test, however, didn't reveal if the panel couldn't tell the difference because the two products actually tasted the same or because there was so much salt in the first product that it affected their sense of taste.

  "This actually got implemented into production," says Maki. "They did a quarterly monitor of the sales results and sales started dropping severely. So they had to go back and reformulate back to the way it was initially."

Favorable flavor

  Besides modifying other tastes, sweeteners can influence the flavor of a food. Sometimes this provides an advantage - masking off-flavors or providing a blending effect, for instance. Some flavors, especially fruit flavors, require a certain level of sweetness to promote the right flavor balance or even to provide recognition.

  "For a honey-flavored ham, you can develop a honey flavor, but without the right sweetness level, you don't really identify the honey," says Maki. "It comes across as a strange off-flavor that no one can quite identify until you tell them it is honey. Often it comes down to delivering the level of sweetness that people anticipate or associate with a particular product."

  Exactly what and how much flavor a sweetener affects depends on the level and the type of compound that is either doing the masking or being masked. Corn sweeteners, especially the lower DE (dextrose equivalent) products, typically have the greatest ability to mask flavors. However, a food designer should keep in mind that this potential extends to good flavors as well as bad. Depending on the end result, the flavor level in a product may have to be increased to compensate for any masking effect.

  Other complex flavor effects can occur. For instance, the National Honey Board's Food Technology Program reports that mixing honey into ground turkey may help reduce off-flavor development promoted by high levels of unsaturated fat in the cooked poultry.

  Samples with added honey showed lower concentrations of aldehydes (compounds that produce off-flavors) than the controls made without honey. High levels of aldehydes are related to the development of oxidative rancidity. It has been proposed that Maillard reaction compounds produced during heating may act as antioxidants during long-term storage or with higher fat meats. More testing is needed to validate these findings further, according to a National Honey Board spokesperson.

  Sometimes the sweetener used contributes a unique flavor of its own. For example, the flavor of honey blends well in many savory applications; ham, poultry, snacks, salad dressings and breads are often formulated with this ingredient. Malt syrups help to flavor bread and other baked products such as crackers. Fruit juices contribute to the flavors of marinades, glazes and dressings.

The color connection

  One of the most important contributions of certain sweeteners in savory products is their connection to Maillard and other forms of nonenzymatic browning. In this relationship, reducing sugars (those that can reduce copper ions) react with the amino acids in proteins, especially under neutral or alkaline pH. This results in the formation of a number of compounds - typically acids, aldehydes and alcohols - that produce brown pigments and characteristic caramelized or roasted flavors. These flavors and colors arise from several different compounds. The exact composition depends on a number of factors, including the time and temperature, the type of sugar and the type of protein.

  The type of sugars and the type of amino acids also affect the rate and extent of the browning reaction. For example, Iysine and fructose provide extensive browning, but the reaction is reduced if the sugar is lactose. Because the sugars form new compounds, the sweetness level of the finished product can change. However, these compounds are critical to the acceptability of the appearance and flavor of savory products such as bread or roasted chicken.

  Dextrose (glucose), fructose, maltose and lactose are reducing sugars, but sucrose is not. However, sucrose can break down into its monosaccharide components through enzyme or heat-induced hydrolysis. These will then react with proteins. Polyols such as sorbitol are not reducing sugars.

  "In corn syrup, the higher the DE the more reducing sugars," explains Joseph Limas, technical service, American Maize-Products Co., Hammond, IN. "There are a lot more reducing sugars that will go through the Maillard reaction. That's one of the important factors to consider in choosing sweeteners. Sometimes that's beneficial, but other times you may not want those color attributes in the finished product. So you may want to go toward a lower DE.

  "High-fructose corn syrups (HFCS) are really going to be over 90 DE," he continues. "Because practically all they consist of is dextrose and fructose, you have a high level of reducing sugars. Because the DE is so high, the industry doesn't really use that term - DE - when talking about high-fructose corn syrups. They talk about the percent of fructose in the product. In the baking industry, for making breads you can use nearly 100% reducing sugars using high-fructose corn syrup. You get a lot of color with the monosaccharides. You just have to decide which are the attributes you want for your final product."

  Corn syrups may contain several components that are inherently subject to browning, such as proteins. Manufacturers may run corn syrup through an ion exchange system to remove most of these and reduce the chance of color pickup. Without ion exchange the syrup will color readily upon storage, especially with elevated temperatures.

  The process and the application determine whether the Maillard reaction will occur. Products that will be exposed to high-heat processes such as baking or grilling will show a much greater effect than something that is merely boiled. The degree of browning is controlled more by the amount of reducing sugar present than by the duration of heating or by the amount of the temperature change. Once browning begins, the reaction takes place quickly; so if excessive browning occurs, the fix is usually found in the formulation rather than the process.

  "One trend we currently are seeing is the interest in rotisserie cooked chicken," says Blowers. "Product developers are starting to ask for more complicated flavor profiles for rotisserie rubs and glazes. Due to the high cooking temperature, there is somewhat of a problem with caramelization of the sugars.

  This poses a challenge when developing, for example, barbecue flavors that are characterized by sweet, tomato flavor.

  "Often alternative sources of sweetness can be used, such as sorbitol, maltol, vanilla or artificial sweeteners," he adds. "In this case, these materials will increase the perception of sweetness and often can function as sweetness enhancers to boost the intensity of the actual sugar flavor in the system. This can help reduce the browning problem in high-heat processes."

  Even though reducing sugars can cause excessive browning, sometimes it is possible to use them in high-heat applications. For example, Maki has had some success with corn syrup solids in glazes and sauces for processed meat products.

  "When we use (corn syrup solids) in a glaze type of application," Maki says, "we have a great deal of moisture, so it probably cools the surface of the product when it evaporates. You don't seem to get the exposure to the direct heat and charring. We end up combining sweeteners for some of the textural benefits where traditionally their use wouldn't be considered."

Collective benefits

  Sweeteners do more than alter color and flavor in savory products. Often they are added for functional reasons, changing the characteristics of the finished product.