Loss of Sulphur Dioxide in the Bulk Storage of Fruit Juices

Losses of SO₂ added to citrus juices, in a typical experiment conducteed on lime juice, were determined in the laboratory at different temperatures in the range 50 to 110°F. At 50°F., 2.3% SO₂ was lost within the firt 5 minutes and 129% during 3 hours after addition. At 110°F these losses were 22.0% and 46.3% respectively. Losses actually determined in the preparation of squash under factory conditions compared reasonably well with the laboratory data. Curves have been presented for approximate calculation of the additional amount of SO₂ at a particular temperature to make up for the loss. Losses of SO₂, which occurred from barrels of juice during storage, were fairly heavy, and seemed to depend on the construction and nature of wood of the barrels, method of handling, temperature, etc. These losses should be occasionally made up by addition of further necessary quantities of the preservative to the juice in barrels.