In a study conducted by University of Illinois scientist Soo-Yeun Lee and featured in this month's Journal of Food Science, Lee developed formulations with 10 grams of protein (6.5 grams of it protein) and five grams of fiber that were intended to overcome the negative taste and texture characteristics often associated with soy.
While commercial products still scored higher for aroma, texture, taste and overall enjoyment with participants, the soy formulations scored an average of 50 percent on an acceptance scale, compared to an average of 70 percent for recognized brands.
The most accepted soy-based cereal would meet the requirements for three different FDA health claims in reducing the risk of cardiovascular disease (CVD) and meeting guidelines for high-protein and high-fiber foods.
"We know we need to do some tweaking but, even at this stage, one of our formulations did better than a product that's already on store shelves," Lee said .
"We're still experimenting with different flavors and sweeteners, but I'm confident that soy-based, high-protein cereals can not only optimize nutrition, they can also taste good."
The study A total of 120 consumers, aged between 18 and 65 and who ate breakfast cereal at least once a week, were asked to compare commercial cereal products with four formulations with soy flour content of 41 percent, 47 percent, 54 percent and 60 percent.
For overall acceptance, scores decreased as the soy flour content increased.
Evaluation with milk significantly increased acceptance scores for aroma and texture, but had no effect on overall and taste acceptance.
The addition of cinnamon did not effect perception of texture, but improved scored for aroma and taste.
The laboratory-developed products scored between 4 and 5 out of 9 in overall acceptance, providing a good base from which to develop tastier products.
The article said: "Although the laboratory-developed products did not perform as well as the commercial products did, it should be noted that the laboratory-developed products are prototypes and a foundation to build and improve upon.
"Among the consumers who participated in the test, over 75 percent considered high-protein content to be somewhat and very important in the breakfast cereals they consume, indicating a need in the market for the type of product that was developed in our laboratory."
The researchers said that future optimization work could include flavors other than cinnamon, such as vanilla, coconut or nuts.
Also, an increase in sweetness was desired by many of the participants, suggesting the need for high-intensity sweeteners that would no change the carbohydrate to protein ratio of less that 1.5.
Soy ingredients Soy has received attention for its hypolipidaemic and hypocholesterolaemic properties, as well as its ability to lower blood pressure, improve arterial compliance and endothelial function, insulin resistance and weight loss in obesity.
"Diets high in soy protein are also effective in combating obesity," Lee said .
"Soy protein is very high-quality protein, and high-protein meals eaten early in the day stick with you so you eat less."
She added: "Because most Americans eat cereal for breakfast, we thought it made sense to boost the protein content of the food they're used to eating."
Many companies have been trying to find ways to base products on soy, by masking its negative taste.
According to the article, basing breakfast cereals on soy has been limited because of objectionable sensory characteristics, and so it has been limited to use as a fortifying ingredient.
The article's author wrote: "Soy foods are associated with beany aroma and bitter taste.
Furthermore, addition of soy into extruded products can have negative impacts on texture, such as decrease in expansion and increase in breaking strength."
Source: Journal of Food Science Published online ahead of print, doi: 10.1111/j.1750-3841.2007.00602.x "Consumer Acceptance of an Extruded Soy-Based High-Protein Breakfast Cereal" Authors: K. Yen, Y. Lee and S-Y. Lee