I occasionally forget to harvest the grapes in my yard in the fall. I thin the fruit from my 11-plant mini-vineyard when I want a finer crop for wine.
You need unripe grapes to make verjus, so how do you do that? Lots of them. For what seems like a small amount of juice, anything you do with grapes requires many pounds of fruit. In the production of wine, the standard ratio is 12 pounds of grapes to 1 gallon of wine. The amount of grapes I used to make my verjus was more like 12 pounds for 2 to 3 quarts of verjus. So yeah, to make this, you’ll need a bucket of grapes.
Fortunately, green grapes grow near you. Most every place in America has wild grapes, usually along riversides. Go find some and fill a five-gallon bucket full. Or thin your personal vineyard…
When life gives you unripe grapes, make verjus, according to the proverb “When life gives you lemons, make lemonade.”
Verjus itself is essentially just tart, acidic grape juice. However, it only adds acidity to a recipe without having the same impact as real vinegar. If you’ve ever eaten vinegar pickles while drinking wine, you know that this is not a good combination. A dish acidified with verjus will remain wine-friendly.
Try roasting them if you’ve ever purchased a bunch of grapes only to find that they were too sour to enjoy; roasting concentrates the sugar content in grapes and improves their flavor. Roasted grapes go well with pork or chicken, and you can also make a compote in a blender or food processor to serve with cheese and crackers. As a dessert or snack, I chose to combine the grapes with plain Greek yogurt and some sesame snaps for crunch.
Keep them close to apples or bananas
Store unripe grapes in a paper bag, possibly with a ripe apple or banana, to further encourage their natural ripening. The reason? The ethylene of these two fruits, i. e. Your sour grapes will be ripe in a few days thanks to the action of the gaseous plant hormone typical of some varieties that continue to ripen even after harvesting: Paper is a material that is able to retain moisture and prevents the fruit from withering or becoming wrinkled while ripening. When it comes to ripening grapes at home without the use of paper, bananas can be a great help. Simply leaving the grapes near a banana or a group of bananas is an alternative to storing them inside of a bag because the ethylene gas from the bananas will cause the grapes to ripen, enabling a relatively quick transformation.
In a wicker basket or box, arrange unripe grapes among apples or pears, covered with cotton napkins. Don’t forget to keep them in a dry, warm location for a few days. Using linen napkins is the final piece of advice for ripening unripe grapes. You’ll need at least two: one for setting the grapes on a table and the other for covering the entire bunch of grapes with closed edges to prevent air from getting in. The only drawback is that this method requires at least a week for the grapes to ripen, but we assure you that the wait will be worthwhile!