Healthier Soups

Purées are especially suited to formulate the drinkable, lunch-type soups that are becoming trendy for at-the-desk dining. These don’t have many particulates.

Reducing fat

“The old term ‘fat-free’ doesn’t have a strong importance like in the past, because consumers understand that fat, in moderation, is good for you and makes the soups taste yummy,” says Mindy Edwards, senior flavor chemist, Wixon, Inc., St. Francis, WI.

Fat produces texture and mouthfeel; it lingers on the tongue and satiates. “Fat is an important part of soups, especially cream soups, where it affects the flavor and appearance, flow properties and mouthfeel,” says Dan Berg, food scientist, Tate & Lyle, Decatur, IL. “The right choice of starches can replace a significant portion of that fat to give you the same texture and mouthfeel at a lower fat level.” Specific-molecular-weight specialty starches have been designed for this type of application. “It mimics the lubricity of fat so you are able to make a soup that has the same mouthfeel qualities of a higher fat at a lower fat content,” he says. “Because fats also contribute to the overall viscosity of the soup,” he says, a wide range of starches “can give you the textural qualities that you expect from cream soup, down to a thinner broth soup that would use less starch.”

Stepan recommends very fine, micropuréed vegetables to replace fat. It’s not a proportional replacement. Less purée will “produce the same mouthfeel as a greater amount of fat,” he says. “If fat is running 30% to 40% in the soup, maybe a 20% micropurée might replace that.” Using butternut as an example, he notes that purées provide more to the eating experience than merely mouthfeel. “You’re going to have a lot of flavors. There’s going to be florals in there. There’s going to be sweetness along with what’s coating your tongue. When it’s over, it’s all going to wash away because it’s a purée, where the fat sticks to your tongue and you have this after-feeling coating. The purées work better in terms of a clean finish.”

Flavor houses offer products for fat-free or lower-fat applications. A fat-mouthfeel enhancer, notes Christopher Warsow, corporate executive chef, Bell Flavors & Fragrances, Northbrook, IL, “works quite well in cream-based soups to accentuate and enhance whatever fat is already present.”

For cream soups, a dry dairy system containing “dairy cream coprocessed with our proprietary ingredients and flavor technology—natural flavors, other dairy ingredients, other nondairy ingredients” produces a 1:1 match for liquid cream when rehydrated at roughly 20% solids, says Marc Janssen, commercial director, Kerry Ingredients & Flavours, Beloit, WI. “This delivers all the flavor and functionality of heavy cream, half-and-half and milk, with the added benefit of roughly half the fat of liquid dairy.”

In the flow

Fricke often uses dehydrated potatoes as a thickener. “You adjust the consistency when you’re cooking by using a little bit,” she says. “You can use it as a base in a purée soup.” She recommends using 1% to 2% for thickening and up to 10% as a base.

Often, starches are used for processing, and for suspension of pasta, vegetables and meats. “With instant soups, the biggest challenge is good dispersion.” Berg recommends an agglomerated-type starch for ease of use, including in “foodservice applications where a foodservice operator will have boiling water and needs to make soup very quickly. A standard starch may lump up if you add it directly into the boiling water, even if it is dispersed in the other dry ingredients. Agglomerated starches will mix in quite easily in close-to-boiling water. The product is ready to go right out to the steam table and serving area. We also have low-temp starches that hydrate at between 120°F and 140°F. It’s not quite a standard cook-up starch, but it doesn’t hydrate immediately upon adding water. It starts to thicken when you start to heat it a little bit.” This provides another way of thickening, without thickening too quickly and causing lumps.

In a typical broth base, Berg recommends a standard, waxy, cook-up starch to give slight viscosity. For steam-table stability, “you typically use cross-linked starches,” he says, a modification that binds the starch molecules together in the starch granule, which helps maintain stability. “Viscosity of starches comes from the swelled starch granule that can hold a lot of water. If you continue to heat that, it can break down. By cross-linking the starch, it will maintain its viscosity and maintain its integrity,” he says. “A properly chosen starch thickens to the right level and maintains its thickness when held on a steam table.”

The challenge with developing frozen soups is protecting against syneresis from freeze/thaw cycles. Berg suggests using substituted modified starches. In substitution, hydroxyl groups are removed on the glucose polymer, and some are replaced with a functional short-chain molecule called a hydroxypropyl unit, he says. “That unit prevents the starch molecules from reassociating with themselves. It increases the water-holding capacity of the starch, so you can use less starch.”

Any ingredient that changes the pH will have an effect on stability. In a tomato-based soup, starches and thickeners must be stable in low-pH conditions. “Starch suppliers have a wide range of levels of cross-linking of starches. It’s simply a matter of choosing the one that will fit the application,” continues Berg.

Salt content affects how starches cook out. The viscosity has a little effect on “how you perceive salt, and a thick soup may be perceived as less salty than a thinner-broth one,” says Berg.

Sodium reduction

The challenge in reducing soup’s sodium levels is that salt has long been used in processed and canned soups. “I believe soup is one of the toughest products to reduce salt in, because salt drives a lot of flavor in soup,” says Warsow. “American consumers have become accustomed to a certain degree of salinity in their chicken soup. When you remove that salt, people instantly pick that up.”

More flavor can be derived from rich, meat-based broths and herbs. “The more flavor you build into a system, the less the mind misses the salt,” says Warsow.

One potassium-chloride-based salt-replacement product “is plated with a proprietary flavor system that does two things,” says Warsow. “First, it enhances salt that is present in the product. Second, it changes the way that your palate perceives the potassium chloride. Our flavor system brings the perception closer to the beginning of the flavor response curve. Potassium chloride has a bit of a late onset of perception, unlike salt, which is immediate.” The system also blocks the bitter, metallic notes that are objectionable when tasting plain potassium chloride, he says

Another product allows a 50% reduction in sodium levels “with all the taste of salt, and it can be used pound-for-pound as a replacement,” according to Bob Kaminski, Wixon, Inc. Other ingredients can mask the bitter, metallic aftertaste normally associated with potassium chloride.