Analyzing Alginate Functionality

Heat-stable gels

In bakery products, alginates are used to form soft gels in fruit preps, fruit-pie fillings and icings. For high-Brix fruit preps, alginate contributes to a smooth texture and sheen, without masking flavor. Its heat stability prevents filling from boil-over when heated.

Alginate is also fully compatible with all types of fruits, pH levels, solids contents and other ingredients typically used in pie fillings. Alginates also can provide a range of textures, from fully gelled to a more-viscous, nongelled structure.

In icing, alginates give improved texture and stability. They are generally effective for icings and frostings at levels between 0.05% and 0.20%.

In water-based dessert gels, alginates form a strong, stable gel with excellent flavor release. Heat is not required for gel formation, and alginate is effective at any pH level and solids content at a usage level of 0.8% or less. Alginates can replace gelatin in these desserts, which is especially important when formulating a vegetarian product.

Emulsion stability

Alginates stabilize both the emulsion and suspend solid particles in creamy salad dressing. In low-fat dressings, PGA can impart some fat-mimetic properties and also boost viscosity lost from fat reduction. PGA has excellent stability in a dressings’ acidic environment, is heat-stable and remains effective at levels of 0.05% or less.

PGA also works as a stabilizer in a variety of beverages. In orange juice, adding 0.1% alginate can stabilize the pulp and provide a subtle boost in body without adversely affecting flavor or other important attributes.

Another beverage application where PGA provides stabilization is whipped fruit drinks, which should have smooth body, stable foam and full flavor. PGA is suitable for these types of beverages since it is effective at any pH and Brix level. It can also be easily dissolved without heat and with moderate shear, although high shear is recommended to obtain maximum foam.

Maureen Akins is a food scientist in the applications section of R&D at TIC Gums, Inc., Belcamp, MD. She currently oversees areas of product development using gums to provide stabilization in meat, bakery, salad dressing, dairy and nonfood applications. Akins has a B.S. in biology and a M.S. in food science, both from Virginia Tech. For more information, e-mail info@ticgums.com.