With droughts in the United States increasingly impacting wheat production , many producers are looking for more durable alternatives. Researchers from Drexel University, the University of Pennsylvania, City University of New York and Monell Chemical Senses Center recently reported that American pallets are likely to accept pearl millet — a hardy, gluten-free grain that has been cultivated for centuries in rugged, drought conditions in Africa and India — as an acceptable substitute in recipes that use wheat flour.
The challenge of introducing an alternative ingredient is always whether or not consumers will like the taste. To understand how U.S. consumers might take to this wheat alternative, researchers from Drexel's Food Lab in the College of Nursing and Health Professions , joined colleagues from CUNY, Brooklyn College, Penn and the Monell Center to, conduct two pilot studies on sensory perception and liking of whole grain, United States pearl millet. Their findings were recently published in the journal Foods .
The results of the study showed that fermented pearl millet flour can successfully replace up to 20% of whole wheat flour in sandwich-style whole grain bread without affecting consumer acceptance or willingness to purchase it. Beyond this amount, however, flavor acceptability declined, which emphasizes the need to balance nutritional improvements with sensory appeal, according to the researchers.
"This study highlights that simple food preparation methods, such as fermentation, can enhance the nutritional value of millet without compromising flavor — up to a point," said lead author May M. Cheung, PhD, an assistant professor at City University of New York, Brooklyn College.
Pearl millet bran contains a considerable amount of phytic acid, an "antinutrient" that reduces the absorption of micronutrients, such as calcium and iron. The research team used fermentation to prepare the millet — a traditional technique that is inexpensive, readily accessible to both consumers and businesses and is consistent with consumer desire for minimally processed foods.
For the first pilot study, 12 adults tasted flat breads made with pearl millet fermented for different durations. The research team found that the longer the fermentation, the more effective it was at lowering phytic acid levels in the millet. But they also found that, for flat breads made solely of pearl millet, the longer the millet was fermented, the less they liked its taste. So, for the second pilot study, the research team substituted fermented pearl millet into whole-grain sandwich bread, in varying amounts, to find out how much fermented pearl millet U.S. consumers would tolerate. Thirty adult participants taste tested sandwich breads made with anywhere from 0% to 50% fermented millet flour as a partial substitute for wheat flour. Again, participants were asked to rate how much they liked the bread samples and if they would buy the bread. The team found that up to 20% of fermented pearl millet flour could be used in sandwich breads before people start rejecting the breads.
"This kind of interdisciplinary research, while familiar in food science, is relatively new in culinary science. Where food scientists often go to the chemistry of food to solve a problem, culinary scientists look to the food's flavors and traditional foodways to solve a similar problem," said Jonathan Deutsch, PhD, professor and director of the Drexel Food Lab in the College of Nursing and Health Professions and co-author of the study. "Being able to access the resources of Dr. Paul Wise's lab at Monell and Dr. Sol Katz, at the University of Pennsylvania, who inspired the project by analyzing videos of traditional millet bread making, is the kind of true interdisciplinary collaboration we need. None of us individually could have gotten to these findings."
The research team noted these findings may have important implications for food manufacturing and public health. Millet is a drought-resistant, nutrient-rich grain that remains not widely used in the U.S. food supply. By identifying an effective way to improve millet's nutritional profile while maintaining flavor, this research provides a simple and practical approach to increasing millet's appeal. It also highlights the value of simple and natural food preparation techniques, according to the researchers, which may be applied to other nutrient-dense grains to enhance their viability in modern food systems.
"I was surprised by how effectively simple practices inspired by traditional knowledge can improve nutrition without requiring a deep understanding of the underlying science," said Cheung, a graduate of Drexel's Nutrition Sciences PhD program. "This simple and more natural method reduced phytic acid levels and improved mineral bioavailability in millet, making it a more nutritious option for the U.S. population."
Cheung added that it was surprising that they could substitute up to 20% of fermented millet flour before affecting how much U.S. consumers like the bread samples. "Perhaps an even higher percentage of fermented millet can be added if we tested these samples in a population that is more familiar with fermented foods," said Cheung.
The continued collaboration of the Drexel Food Lab, the University of Pennsylvania, City University of New York, Brooklyn College, Monell Chemical Senses Center and other partners will further refine the balance between nutrition and sensory properties in the millet food formulations.
"Our goal is to identify the 'sweet spot' where we maximize both health benefits and consumer acceptance, ensuring that underutilized, nutrient-rich foods, like millet, can become more widely integrated into the U.S. diet," said Cheung.
In addition to Cheung and Deutsch, this study was co-authored by Lauren Miller and Rachel Sherman, of Drexel; Solomon H. Katz, PhD, of the University of Pennsylvania; and Paul M. Wise, PhD, of the Monell Chemical Senses Center. Read the full study here: https://www.mdpi.com/2304-8158/14/5/871 .
