Skip to main content

Flour Power: Exploring the Nutritional Potential of Grape Pomace Flour

“Leftovers” isn’t exactly the first thing I think of when it comes to wine, but fortunately it’s something Barbara Banke and Peggy Furth, founders of Whole Vine, considered.

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


“Leftovers” isn’t exactly the first thing I think of when it comes to wine, but fortunately it’s something Barbara Banke and Peggy Furth, founders of Whole Vine, considered. Their whole vine concept uses the parts of the vineyard left over from wine--the seeds and skins--to create 16 different varieties of flour based on the different wine grapes, such as Zinfandel, Syrah, Riesling and Chardonnay.

About 80% of the total harvested grape crop is used to make wine. Grapes are gathered and then pressed to extract juice. Then, it’s the winemakers, not the grapes, that become pressed when it comes to the dilemma of what to do with the remaining 20 percent. Pomace (the solid leftover seeds, skins, and pulp) has been used as compost or converted to fertilizer and animal feed. However, pomace is packed with nutrients, leading to an interest in exploring its use in food.

Along with being gluten-free and high in fiber, pomace flour contains a bevy of chemical components, including phenolic compounds. In wines, phenols provide structure and color, and may have significant health benefits. Some of these phenols are retained in grape pomace. One study found over 39 types of anthocyanins, hydroxybenzoic and hydroxycinnamic acids, catechins, flavonols and stillbenes within grape pomace. Other research has explored their health potential: phenols within grape pomace have been shown to exhibit powerful antioxidant properties, inhibit the oxidation of human low-density lipoproteins, and also act as free radical scavengers.


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


Besides being nutritious, research has shown pomace flour can be a tasty addition to products such as bread, yogurt and salad dressing. In the name of research, I decided to test it myself. This was the tough part. Okay, that’s not true at all. Kendall-Jackson is a sister company to Whole Vine and their chefs regularly incorporate pomace flour into their dishes. I got to try some of these treats, including:

Trout accompanied by a fried green tomato dredged in chardonnay flour, along with chardonnay grapeseed oil in its natural state and also in powder form, a transformation made possible with the addition of tapioca maltodextrin.

And for dessert, basil panna cotta served with chardonnay cake.

Feeling inspired, I decided to do a little experimenting with pomace flour. After some serious deliberation (pasta? bread? brownies? all three?) I decided on an orange and almond biscotti that uses chardonnay flour and another pomace incarnation, grappa. "Biscotti" comes from the Latin bis cottis, meaning "twice cooked." After their double baking, these crunchy cookies are ready to be served in traditional Tuscan style, by dipping them into the Italian wine, vin santo.

Chardonnay Orange Almond Biscotti

(Modified from this recipe in Bon Appétit)

3 cup all purpose flour

¼ cup chardonnay flour

1 tablespoon baking powder

1/3 teaspoon salt

1 1/2 cups sugar

10 tablespoons (1 1/4 sticks) unsalted butter, melted

3 large eggs

1 tablespoon grappa

1 ½ tablespoons orange zest

1 cup whole almonds, toasted, coarsely chopped

1 large egg white

PREPARATION

Position rack in center of oven and preheat to 350°F. Line baking sheet with parchment paper.

Sift flours, baking powder and salt into medium bowl. Mix sugar, melted butter, 3 eggs, grappa and orange zest in large bowl. Add flour mixture to egg mixture and stir with wooden spoon until well blended. Mix in almonds.

Divide dough in half. Using floured hands, shape each dough half into 13 1/2-inch-long, 2 1/2-inch-wide log. Transfer both logs to prepared baking sheet, spacing apart.

Whisk egg white in small bowl until foamy; brush over top and sides of each dough log.

Bake logs until golden brown (logs will spread), about 30 minutes. Cool logs completely on sheet on rack, about 25 minutes. Maintain oven temperature.Transfer logs to work surface; discard parchment paper. Using serrated knife, cut logs on diagonal into 1/2-inch-wide slices. Arrange slices, cut side down, on same baking sheet. Bake 12 minutes. Turn biscotti over; bake until just beginning to color, about 8 minutes. Transfer to rack and cool. (Can be prepared 1 week ahead. Store in airtight container at room temperature.)

Image Credits: davitydave, memegenerator, remainder by author.

Layla Eplett writes about the anthropology of food. She has a Masters in Social Anthropology of Development from the University of London's School of Oriental and African Studies and loves getting a taste of all kinds of culture--gastronomic, traditional, and sometimes accidentally, bacterial. Find her at Fare Trade.

More by Layla Eplett