The mixture of pulp, seeds and skins is called mash.
Grappa, is brandy made from the juice of grape skins and seeds, also called pomace.
Tannins in wine come from the skins, seeds, and stems of grapes.
White wine is made from "white" grapes, red wine from "red" grapes. As you have noticed, so-called white grapes aren't exactly white. They vary from green to grayish. while "red" grapes can be from red, to almost black. Blush wines, or rosé, are made by removing the grapes skins shortly into the fermentation process. The grapes are crushed, as in normal wine-making, but then the skins are filtered out after a couple of days. Much of a wine's color comes from the skins of the grapes.
The word for pressed grapes is "must." Must refers to the freshly crushed grape juice that contains the skins, seeds, and stems, which is the primary ingredient in winemaking. After pressing, the must undergoes fermentation to produce wine.
The unique flavor and characteristics of wine come from compounds called phenols, which include tannins, anthocyanins, and flavonoids. These compounds are found in the skins, seeds, and stems of grapes, and contribute to the taste, color, and mouthfeel of the wine.
pomace -- the refuse from grapes, skins, etc...
Normally Red wine is made with red grapes, and White wine with white (greenish) grapes. Red wine get its color from the red skin being in the mix that get squeezed (with seeds and all), and left weeks fermenting. White wine is fermented without the skin and seeds (these are filtered out before starting the fermentation process). It is, though, possible to make white wine out of red grapes by removing the red skin prior to fermenting. This type of wine is called 'blanc de noirs' (white from black).
No, but white wine can be made from red grapes if the extracted juice is not kept in contact with the red skins.
Filter
The primary berry used in winemaking is the grape. Different varieties of grapes, such as Cabernet Sauvignon, Merlot, Chardonnay, and Pinot Noir, contribute unique flavors and characteristics to the wine. The fermentation process of crushed grapes, along with their skins, seeds, and stems, results in the production of wine, with the type of grape largely determining the wine's style and taste.
Don't use the skins in the fermentation, just the clear pulpy flesh of the fruit