Grapes to be shipped as fresh are packed in wooden crates, then pre-cooled to about 40 ° F (4.4 °C) in railroad cars or refrigerated rooms. Grapes destined for immediate delivery are sometimes shipped without pre-cooling though they should be shipped in a refrigerated container.
Grape bunches can be arranged in different ways in the containers. In the stem-up pack arrangement clusters stems are in full view but packs are attractive. Fresh grapes can be packed in this manner with very little handling injury.
Generally, the grapes will be fumigated with sulfur dioxide prior to or during cooling to prevent mold growth.
Grapes that are to be stored for future shipment should be packed in crates, pre-cooled to 36-40 °F (2.2 - 4.4 °C), place in refrigerated storage 29- 32 ° F (-1.67 – 0 °F), and fumigated with sulfur dioxide and should be held ih this manner until shipped.
Periodic re-fumigation with sulfur dioxide may be required to prevent spoilage by molds.
Most table grapes are packed as they are picked to avoid extra handling. A large part of the California grape crop is packed in the vineyard. This method has some advantages over the house-pack method:
• Less capital investment in packing facilities
• Only a vineyard crew to mange rather than a picking and lacking crew whose production must be coordinated
• No large inventory of filed lugs