Wine, Nongrape

Winemaking is one of the most ancient of human endeavors. Archaeological evidence suggests that early winemakers began practicing their art nearly eight thousand years ago. Since then, efforts have been largely directed toward controlling the fermentation of the grape. United States regulatory agencies classify nongrape wines by their primary component into apple or pear, fruit or berry, citrus and agricultural wine. The latter includes wines made from honey, root crops, flower parts, cacti, and rice.

Successful fermentation of nongrape materials presents a variety of challenges. Most important is increasing the sugar content in the fruit or other component. At optimal maturity of any fruit, the sugar content is insufficient to yield a wine of 10+ percent alcohol. As a result, winemakers are allowed to add sugar, a process called chaptalization. A winemaker also needs to control acidity since fruit and vegetables are often deficient. The deficiency is corrected by addition of either citric or malic acids or by blending higher acid fruit or wine. In contrast, citrus and some berries may be too high in acidity, a defect that can be corrected by the practice of amelioration or regulated addition of water. Nitrogen deficiencies may arise from the fruit and/or processing and, if critically low, result in interrupted or stuck fermentation. Such fermentations require addition of exogenous nitrogen, typically in the form of diammonium phosphate (DAP). With the exception of berries, processing of fruit and vegetable products generally results in very poor juice yields. Pectinase enzyme preparations may be used to attack cell wall structure, liberating fluid. Alternatively, the fruit may be frozen and thawed before processing. Formation of ice crystals ruptures cell walls, which then release fluid and increase juice yield. However, this may result in premature oxidation and diminished fruit character. An alternative, fermentation of macerated pulp, rather than of expressed juice, will trap heat of fermentation and increase the probability of stuck fermentation. In contrast, fermentation of larger volumes of juice requires cooling capable of dissipating heat.

When making mead or honey wine, the principal component, honey, is typically 70 percent sugar or more, with the compositional balance reflecting type and origin of the flowers. Honeys may range in color and flavor from light, mild, and fragrant to darker and more strongly flavored. Since refined honeys have reduced character, due to thermal processing, mead producers prefer to purchase unprocessed or minimally processed honey. While intensified in flavor and aromatics, natural honey is prone to crystallization when stored at refrigeration temperatures. Although sensorially unapparent, honey is acidic (average pH 3.9). The primary acid is gluconic (5.7 g/L) with lower concentrations of other common acids, which reflect the honey's origins.

Pulque is fermented from the sap (aguamiel ) of the Agave (Maguey), a succulent plant indigenous to the desert highlands of central Mexico. Bacteria, primarily Zymomonas mobilis, and yeasts have historically been responsible for alcoholic fermentation; however, modern producers use commercial yeast (Saccharomyces cerevisiae ). Wine made from melons is not as successful as those made from other products. Unless cofermented or blended with more highly flavored fruits, melon wines are generally insipid. Further, color is colloidal: A variety of melon that is red when fermenting will become straw-yellow upon clarification and bottling.

Dandelion wine is probably the best-known example of wine made from flower parts. Although most view dandelions as a nuisance, the flower has a long history as a medicinal herb and teas. Petals are excised, boiled, and extracted in various formulations of sugar and acid (citrus fruit or juice) for several days prior to straining and addition of yeast. Since petals are typically low in available nitrogen, supplementation is required.

Berry fermentations from cultivated and native berries are relatively simple. Most have adequate to excess acidity and juice/wine yields are acceptable. Apple wine (cider, hard cider, apple jack) is also an ancient beverage, and consumption of fermented apple juice is well over two thousand years old. English colonists brought apple seeds to north America where both "hard" and nonalcoholic juice became their most popular drink. Pear wine, also known as perry or poire, has its origins in both the England and Normandy region of northern France. Compared with ciders, perrys have more refined and ephemeral aromas. Perry also contains a high level of the nonfermentable sugar-alcohol, sorbitol, resulting in a more full-bodied presentation.

Included in the stone fruits category are wines made from numerous varieties of peaches and nectarines, plums, apricots, and cherries. Each presents unique challenges. As noted above, the most significant issue is juice yield. Enzyme additions are helpful. Produced from either cultivated or native species, cherries yield a relatively distinctive and easily managed fruit wine. Cherry pits contain organic cyanides either as cyanogenic glycosides or hydrocyanic acid. Therefore, any cracked seeds should be separated from the pulp prior to fermentation. Among commercially available varieties, sour cherries, such as Montmorensay, are sought after due to their already high acidity. However, sweet cherries may also produce excellent wine upon blending or with acid supplementation. "Wild" or chokecherries are common to much of North America. Chokecherries derive their name from their extraordinary acidity or "sourness" compared with cultivated cherries.

See also Alcohol ; Apple ; Beer ; Berries ; Fermentation ; Fermented Beverages Other than Wine or Beer ; Flowers ; Fruit ; Sugar and Sweeteners ; Wine .

K. C. Fugelsang