SPONGE CAKE RESEARCH STUDY
Snack cakes are a long time staple of the bakery industry. And one of the most commonly available snack cakes in retail stores in the U.S. is the sponge cake, a type of foam cake that relies on whole eggs. Its tough and resilient structure is necessary to withstand filling, frosting and packaging.
Overall, not a single product performed as well as or better than real eggs in all attributes assessed.
The areas of sponge cake quality most negatively affected when eggs are removed and/or replaced included batter viscosity, color/appearance and texture.
Tasters unanimously preferred the Control to the Test formulas at the start of testing. Its golden brown color, high rise, even top, uniformly open cell structure, and sweet, eggy baked good aroma and flavor won panelists’ approval as the most appealing sponge cake. It was neither dry nor moist, and its structure was tender in the mouth, yet firm and pleasant to chew.
Sponge Cake Visual Comparison
Made with REAL EGGS
Made with EGG REPLACERS*
For this study, researchers prepared a control or gold standard formula using whole eggs. The team also prepared test formulas with eggs reduced and/or removed from the sponge cake formula and substituted with products marketed as egg replacing ingredients for food manufacturers. Analytical tests and organoleptic sensory evaluations were performed on each sponge cake formula.
Seven egg replacer ingredients were tested including:
- Starch-based blend
- Soy-based blend
- Whey protein concentrate
- Wheat protein isolate
- Blends of various ingredients
- Fiber-based blend
The recommended egg replacement varied from 20 to 100 percent. Suppliers generally recommended keeping the ratio of moisture to dry ingredients the same. (When removing some or all of the liquid egg from a formula, moisture is lost and needs to be added back in the form of water to balance the formula.)
Different egg replacer ingredients have varying water absorption capacities. If an ingredient absorbs an excessive amount of water, additional water may need to be added to the formula to obtain the correct batter viscosity to flow through production equipment. Additionally, this can lengthen bake times to get the correct internal temperature and final moisture content.
Both the batter and cooked, cooled cakes were analyzed using industry standard, category-specific tests. Consistent batching, mixing, portioning and baking procedures were used to limit variables.
Tests used to assess sponge cake batter and finished cakes:
- Batter specific gravity
- Batter viscosity
- Baked good height & shape
- Water activity
- Subjective/sensory tests
- Cooked appearance
- Cooked aroma
- Overall likeability
*This photo represents only 1 of 7 egg replacer products.