Beany flavour study to enhance the appeal of soy-based foods

The soy-based foods market has been experiencing rapid growth in recent years, driven by increasing health consciousness and rising demand for plant-based alternatives for milk, meat and other products. However, while a beany flavour might be acceptable in foods like tofu or soy milk, it’s less welcome in products such as plant-based burgers or protein shakes.

Researchers at the University of Missouri have been recently working on developing novel ways to overcome the flavour challenges associated with soy-based food to create wider interest for the products and also potentially improving the nutrional value of the foods in the process.

In the study, Bongkosh “Jeab” Vardhanabhuti, an associate professor of food science at University of Missouri, and her team at the College of Agriculture, Food and Natural Resources compared the taste and aroma of four soybean varieties — three of them being specially bred by the university's plant scientists. All the varieties were grown under identical conditions and processed into a raw soy slurry, similar to uncooked soymilk.

The researchers found that a variety called “Super” yielded the best results, delivering the most pleasant flavour and aroma, making it more appealing to Western consumers.

Specially bred soybeans

“People in Asian culture have been using soybean products for centuries. Now, more and more Western consumers are interested in soy products, and we are looking to offer options for everyone,” Vardhanabhuti said.

The specially bred Super soybean used by researchers was designed with a healthier fat profile. Plant scientists also reduced certain sugars that don’t offer nutritional value and removed an enzyme called lipoxygenase, a key culprit in creating off-flavour compounds.

“Overall, this research shows that smart plant breeding can make soy-based foods taste better, which could help more people accept and enjoy them,” Vardhanabhuti said.

For this study, researchers prepared the raw soy slurry by washing the soybeans, soaking them in water overnight and then grinding them with fresh water. The mixture was strained and refrigerated. They measured protein, fat, moisture, fibre and ash content using standard laboratory methods. Additionally, gas chromatography was used to analyse the types of fats in the soy oil, while ion chromatography and enzyme tests measured sugars such as sucrose. Finally, several tests were conducted to assess aroma compounds.

Nine trained panellists — all experienced in sensory testing — evaluated the slurries based on 12 traits: colour, five aroma characteristics and six flavour characteristics.

“There’s a clear need for soybeans with a milder or even neutral flavour profile — beans that can be added to a variety of products without announcing themselves on the palate,” Vardhanabhuti said.

This research is the first in a series of studies that Vardhanabhuti’s research team is conducting to improve the taste of soybeans. Next, the team will examine improving the taste in products such as tofu, soy milk and soy protein.

The findings have been published in Food Chemistry.

Image credit: iStock.com/BongkarnThanyakij