Red wine pomace may have heart health benefits

Sept. 25, 2024 – DENTON – Scientists can’t seem to agree on whether a glass of red wine is good for you or not. But, what about the waste from fermented grapes used to make wine?

Mandana Pahlavani, PhD, an assistant professor from Texas Woman’s Department of Nutrition and Food Sciences, received a $300,000 grant from the U.S. Department of Agriculture (USDA) to study the “novel microencapsulation of red wine pomace to modulate gut health in coronary artery disease.”

Pahlavani is the project director for the study and her co-principal investigator is Naima Moustaid-Moussa, PhD, from the Institute for One Health Innovation at Texas Tech. She is also collaborating with Ahmad Kalbasi, PhD from the Texas A&M Biological and Agricultural Engineering Department.  

Pahlavani’s study focuses on increasing the bioavailability of polyphenols obtained from the red wine pomace. Grape pomace is the leftover waste after grapes are pressed to make juice or wine. This could be the skins, seeds, stems and pulp from a grape. And, red wine pomace is the pomace after the grapes have been fermented. 

Previous research has shown that polyphenols, which contain antioxidant and anti-inflammatory properties, have many health benefits. Red wine pomace, due to its fermentation, contains even more polyphenols. 

“We hypothesized that encapsulation of red wine pomace will enhance the bioavailability of its antioxidant by increasing the good bacteria population in the human gut and improving cardiovascular disease,” Pahlavani said.

The encapsulation of the red wine pomace is one of the unique aspects of Pahlavani’s study. By encapsulating the red wine pomace, Pahlavani is hoping to protect the antioxidants from the human body’s metabolism system. 

“Polyphenols have antioxidant properties affecting gut microbiota; however, their bioavailability is very low,” Pahlavani said.

Pahlavani and her team of students will spend the first year of the two-year grant working in her Nano-Nutrient and Cardiometabolic Research (NNCR) lab on the encapsulation. This involves grinding the red wine pomace into a fine powder and wrapping it in a shell.

“We can’t see that structure because it’s very small,” Pahlavani said. “Nano-size has a core and a shell. The core is red wine pomace and the shell is a protein. It is called a capsule because it has a shell.”

After ensuring the shell’s protection through an electronic microscope, Pahlavani and her team will then test the encapsulated red wine pomace with a gastric simulation system, like an artificial human digestive system.

The second year of her study will focus on feeding mice the encapsulated red wine pomace and then measuring the gut microbiota diversity. 

“Successful results from this study will lead us to the next phase, which is the clinical study,” Pahlavani said.

Not only could her study have a beneficial impact on the human body, it can also help the environment. Byproduct grape waste has been a sticky problem for winemakers.

Grape pomace makes up about 10% to 25% of the weight of grapes. That leads to the wine industry producing 10 to 12 millions tons of grape waste every year. Winemakers have looked for sustainable uses for the pomace, using it as fertilizer, animal feed or a renewable energy source. 

It’s only been recently that researchers and food scientists have looked more closely at the healthy compounds in grape pomace. You may have heard of grapeseed oil, which is extracted from grape seeds during the winemaking process. 

“Most studies have focused on the health benefit effects of grape seed and no study has investigated or compared the availability of antioxidants in red wine pomace,” Pahlavani said.

Many wineries are looking for ways to reuse or offload their grape pomace. The red wine pomace for Pahlavani’s research came from Messina Hof Winery in Bryan, Texas.

“Results of our study can make a significant impact by providing a nutritionally rich and cheap source of antioxidants with higher availability, resulting in improving gut health,” Pahlavani said.

In the future, people might walk into their local grocery store and purchase juice enriched with red wine pomace.  

Not the same thing as a glass of red wine, but it will hopefully cause less controversy.