Harvesting grape

When to harvest grapes may be one of the most quality-oriented decisions a winemaker has to make. To obtain the full flavor, body, and color, the grape must be mature when harvested. Both immature and overripe fruit produce inferior red wines. 

The harvested grapes are delivered primarily to the wineries in gondola tanks on a truck flatbed. The size of these containers ranges from two tons up to eight tons per container. There is no standard size for these grape containers. The size of grape load delivered also varies. 

Harvested grapes are delivered to the wineries within a few hours after harvesting to ensure that the fruit is in sound condition. The wine industry, recognizing the importance of sound fruit in winemaking, instituted a wine grape inspection program with the State of California. This voluntary program was initiated in 1957. 

To vinify separately the mechanical harvested grapes, when the sanitary quality of the crop is poor ... 

Zimmerli and Dick (1996) pointed out that apart from climatic differences, different practices in grape cultivation (e.g., use of pesticides or different cultivars, and wine making) may influence the ochratoxin A concentration in wine. The latter include time and condition of storage of harvested grapes, type of maceration, and time and temperature of fermentation. 

In 1996, 22 farm workers were hospitalised while harvesting grapes after being poisoned by drift during the application of pesticides in a nearby cotton field. 

Wine production is a fundamentally simple process, with the potential to be highly nuanced (Figure 19.1). Following harvest, grapes are crushed and the resulting must (juice H-seeds-t-skins) is used either directly for fermentation (red wines) or pressed to release the juice from the skins and seeds (white and blush wines). Grapes are not... 

PROCESSING. Harvested grapes reach consumers through several routes table grapes, canned grapes, juice, jam, jelly, raisins, and wines. In recent years, the U.S. crop has been processed as follows wines, 48% raisins, 31% table grapes, 15% juice, jam, and jelly, 5.7% and canned, 0.7%. 

In future, Fourier transform infrared spectrophotometry will be an invaluable tool for assessing the condition of harvested grapes. This method is already capable of detecting the presence of rotten grapes, but there is no close correlation with the measurement of laccase activity. 

Mechanical harvest transport does not follow the same rules. The harvested grapes should be brought rapidly to the winery after the juice has been separated from the solid parts to the extent... 

Mechanically harvested grape crops, especially white, require rapid draining. This is most often effected with grills forming a double floor in the bottom of bin trailers. 

Sorting the harvest to eliminate bad grapes is only possible with intact grapes. This operation is difficult with machine-harvested grapes. Cutters, however, may precede the harvester to eliminate most of the damaged, spoiled or unripe grapes. 

According to the literature, Champagne must contains 25-100 mg/1 of proteins (in BSA equivalent), while the level is considerably lower in base wine 14-32 mg/1 (Tusseau and Van Laer, 1993). In harvested grapes, 75% of total nitrogen is in amino acid form, while it accounts for 95% in new base wine (Tusseau et al 1989). 

GRAPE JUICE. In laboratory tests, unfermented grape juice caused mild attack (2 mpy) of 1100,3003, and 3004 alloys at room temperature. Aluminum alloy equipment has been used for harvesting grapes and grape juice has been transported in aluminum alloy tank cars (see Fruit and Fruit Juices). See also Ref (4) pp. 88, 91. (6) p. 10. 

Juice (d = 1.0 g/mL) from freshly harvested grapes has about 24% sucrose by mass. What is the molality of sucrose, CeH Oe, in the grape juice after 25% (by mass) of the water content has been removed Assume a volume of 15.0 L. 

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