Lemons trees may be grown from nursery root stock, but mostly the fruit is grown on graft made on stock of the sour orange.
Once established, the trees may bear fruit for many years. Since the trees, and particular the fruit, are damaged by freezing temperatures, they may have to be protected in cold weather.
Lemons are produced in United States, mainly in California and Arizona.
They are harvested when the skin in green or silver in color and ripened to a yellow color in bins, the air of which contains some ethylene.
Most lemons are marketed in the fresh state, and as such are handled in much the same manner as are grapefruit.
Cooled to about 32 degree F and held at this temperature, fresh lemons have a storage life of 1 – 4 months.
Some lemon juice is prepared and frozen as a lemonade concentrate. The fruit is washed, sized and inspected, after which the juice is extracted and screened.
Sugar is added to provide a soluble solid to acid ration of 14:1 – 19:1. The mixture is then evaporated at low temperature under vacuum to provide a 5:1 concentrate.
The screen pulp (which contains some liquid) is then added to the concentrate to provide 2.4 – 4% pulp by volume.
The concentrate mixture is frozen to a slush having a temperature of 25 degree F ( - 3.9% degree C) in a refrigerated heat exchanger.
The slush is filled into cans, the cans sealed and conveyed through a cold air tunnel until the product is cooled to a temperature of – 18 degree F (-27 degree C) or lower.
Some lemon juice is evaporated to a concentration of about 2:1 and packaged in glass or plastic containers with 0.1% sodium benzoate. Pulp and sugar are not added to this product, which requires no refrigeration. Pectin is manufactured from lemon peel as in the case of grapefruit.
Lemons
