PGA ,a derivative of alginic acid, is a strong emulsifier that imparts a range of viscosities, depending on its degree of esterification. PGA can also be used to create thick, creamy texture and lingering mouth-coating. Gum acacia also has emulsification properties.
Guar gum is often utilized as a low-cost thickener. While guar alone can yield a slimy mouthfeel, synergy with xanthan gum provides an excellent texture at reduced cost (compared to xanthan alone).
Grace Wang, food scientist, TIC Gums, Inc., White Marsh, MD, suggests that blends are often needed to create and stabilize the complex textures of dressings. “Xanthan used for thickening may be combined with emulsifiers that help keep oil and water from separating,” she says. Blends might also incorporate additional gums to provide specific textural properties. “Microcrystalline cellulose, MCC, helps provide a fatty mouthfeel,” she notes. “Cellulose gel acts as a fat mimetic, giving a full-fat mouthfeel in lower-fat products.”
In dairy-based dressing, kappa-carrageenan can be useful because of its interaction with protein. And in vinaigrettes, iota carrageenan might be used to help suspend herbs and other particulates.
Blends can also be used to replace ingredients. Combining xanthan and modified gum acacia, for example, can replace a portion of eggs. According to Wang, modified gum acacia delivers greater emulsifying power than regular acacia, and at lower cost than PGA.
Protein punch
Proteins can also enhance viscosity and mouthfeel in dressing applications. “Whey protein concentrates are treated under different processing conditions to obtain the differences in mouthfeel, texture and flavor,” says Ludtke. These specialized whey protein concentrates (WPCs) can deliver a range of textural effects, from mild increases in viscosity to creamy gel-like mouthfeel, as well as flavor notes such as mild, milky and creamy; slightly sweet dairy; or a slightly tart dairy, which she says is especially complementary with cheese flavors.
Ludtke suggests a 2% use level will create a notable difference in viscosity. Specific levels will, of course, vary, especially when using WPC to replace another ingredient. “If you use nonfat dry milk in your formula, you can use half the amount of WPC as your nonfat and replace the rest with water to get the same viscosity,” she says.
Creamy mouthfeel, dairy notes and opacity make WPCs ideal for fat replacement, especially in buttermilk or ranch-type dressings. Ludtke adds that WPCs are often added to gum-containing systems to enhance the creamy texture while providing a longer, smoother pour.
R. J. Foster is a wordsmith with a B.S. in food science from the University of Wisconsin-Madison and over 15 years of experience in the food industry. He can be reached through his website,
wordsmithingbyfoster.com.
Dressing Data
According to a recent Kraft Foods’ Salad Dressing “Pure Taste” survey, a national consumer poll of 1,000 adults conducted by TSC, a division of Yankelovich, 81% of Americans eat at least one salad a week, with one in five eating a salad almost every day. Most (77%) refuse to eat salad without dressing and many (70%) use salad dressing as a dip or marinade. In addition, many prefer salad dressing with no artificial preservatives (66%) and nearly half (46%) prefer low-fat or fat-free salad dressing. The favorite flavor list is topped by ranch (30%), followed by blue cheese (14%), Italian (10%) and French/Catalina (9%).