The Collaborative International Dictionary
Verjuice \Ver"juice`\, n. [OE. vergeous, F. verjus, that is, the juice of green fruits; verd, vert, green + jus juice. See Verdant, and Juice.]
The sour juice of crab apples, of green or unripe grapes, apples, etc.; also, an acid liquor made from such juice.
Tartness; sourness, as of disposition.
Wiktionary
n. A very acidic juice made by pressing unripe grapes.
Wikipedia
Verjuice ( ; from Middle French vertjus "green juice") is a highly acidic juice made by pressing unripe grapes, crab-apples or other sour fruit. Sometimes lemon or sorrel juice, herbs or spices are added to change the flavour. In the Middle Ages, it was widely used all over Western Europe as an ingredient in sauces, as a condiment, or to deglaze preparations. It is still used to some extent in the American South.
It was once used in many contexts where modern cooks would use either wine or some variety of vinegar, but has become much less widely used as wines and variously flavoured vinegars became more accessible. Nonetheless, it is still used in a number of French dishes as well as recipes from other European and Middle Eastern cuisines, and can be purchased at some gourmet grocery stores. The South Australian cook Maggie Beer has popularised the use of verjuice in her cooking, and it is being used increasingly in South Australian restaurants.
Modern cooks most often use verjuice in salad dressings as the acidic ingredient, when wine is going to be served with the salad. This is because verjuice provides a comparable sour taste component, yet without "competing with" (altering the taste of) the wine the way vinegar or lemon juice would.
Verjus, called husroum (حصرم) in Arabic, is used extensively in Syrian cuisine. In Syria, much of the production of husroum is still done over the course of several days by female members of land-owning clans—even if many of them live in cities. The husroum produced during this time will be distributed to various households within the extended family and used throughout the year. The same is true for the production of olive oil and tomato paste.
Verjus, called ab-ghooreh (آبغوره) in Persian, is used extensively in Northern Iranian and Azeri (i.e., native Azerbaijan) cuisine, such as in Shirazi salad.
Usage examples of "verjuice".
Genoa, La Bochetta, and La Scrivia,--an opinion which I share and which Napoleon adopted,--not to speak of the verjuice with which the Alpine rocks have been bespattered by other learned men,--is it surprising, Monsieur le marquis, to see modern history so bemuddled that many important points are still obscure, and the most odious calumnies still rest on names that ought to be respected?
Crab Apple, armed with thorns, grows in our fields and hedgerows, furnishing verjuice, which is rich in tannin, and a most useful application for old sprains.
The man was so full of verjuice that he could not resist an opportunity of squirting a drop or two m my direction.
After the pieces cool, they are put into close vessels and over them are poured either good small ale or beer mingled with verjuice and salt.
Afterward, putting it into close vessels, they pour either good small ale or beer mingled with verjuice and salt thereto till it be covered, and so let it lie (now and then altering and changing the sousing drink lest it should wax sour) till occasion serve to spend it out of way.