Faced with growing concerns about food waste and protecting the environment, scientists are finding smart ways to turn leftovers into useful new items. A clear example comes from fruit processing—specifically, the pulp, skins, and seeds left after apples and grapes are pressed to make juice, cider, or wine. This leftover material, often tossed aside, is now being viewed as a promising ingredient for creating new and flavorful drinks.

Researchers Dr. Zhuoyu Wang, Dr. Andrej Svyantek, and Dr. Zachariah Miller, working at Texas A&M University and Montana State University, explored this idea by mixing apple and grape remnants to make blended fermented beverages. Their findings, shared in the science journal Fermentation, looked closely at how these mixtures behaved during the fermentation process, which is the natural conversion of sugars into alcohol by yeast, and how the final drinks turned out.

Changing the blend of apple and grape material led to noticeable differences in how the drinks fermented and what they tasted like. When more grape was used, the fermentation moved faster, bringing in more sugar and nutrients helpful to the yeast, a microorganism that drives fermentation. On the other hand, using only apple leftovers slowed down the process and required an extra round of yeast to finish the job. The final drinks also looked different depending on the mix—grapes brought in red shades, while apples created yellow tones.

Each fruit also added its own unique flavors and helpful plant compounds. Grapes offered more of the tart and bold elements often found in wine, while apples added a smooth, fruity touch. Together, they formed a balanced drink with layers of flavor. As Dr. Wang described, “The dynamic color changes indicated that grape pomace contributed to the wine’s red color, whereas apple pomace mainly contributed to the yellow coloration in the fermented products.” Pomace refers to the crushed fruit skins, pulp, and seeds left over after pressing.

Reviewing the finished beverages, the team found differences in alcohol strength, tartness, and health-related properties like antioxidants, which are compounds that help protect cells from damage, depending on how the fruits were blended. One of the best combinations turned out to be an equal mix of apple and grape, which delivered a drink with smooth alcohol levels, appealing taste, and just the right level of sharpness. This blend also showed how two types of fruit waste can work together to make something better than either one alone.

More than just flavor, this experiment showed how fruit waste can play a bigger role in making food systems more sustainable. As Dr. Wang noted, “This fermentation study indicated the potential application of grape and apple pomace in the wine industry.” Using these leftovers helps reduce waste and supports a circular economy, which is an approach where materials are reused and recycled to minimize waste, ensuring that every part of the harvest is used for something valuable instead of being thrown away.

Dr. Wang and her team believe this kind of study points to real-world solutions. By using parts of the fruit that usually go unused, beverage makers can create new products that taste great and help the environment. These efforts show how science can help industries think differently about what they throw out—and what they could turn into something better.

Journal Reference

Wang, Z.; Svyantek, A.; Miller, Z. “Apple and Grape Waste Pomace Fermentation and Co-Ferment Product Chemistry.” Fermentation, 2025, 11, 126. DOI: https://doi.org/10.3390/fermentation11030126