The Dutch tried to establish vegetable gardens on their East Indies fleet but found it impracticable. During the end of the 18th century sprouted beans-a rich source of vitamin C-were recommended as an antiscorbutic, but malt (sprouted barley), after it had been dried and stored as a powder on board ship, was of minimal value. The use of malt soup, made by heating malt extract with milk, was associated with a high incidence of infantile scurvy. Beer was also repeatedly recommended as an antiscorbutic. Beer consumed immediately after the fermentation period, and not boiled before fermentation, might have been an effective antiscorbutic. However, beer produced commercially after 1850 was devoid of vitamin C (Watt, 1982).
Another drink prized by sailors since the 16th century was "spruce-beer" made from the green leaf buds of fir trees. Extracts made from leaves of the American spruce, the tree thought to have been used by the Canadian Indians who shared their remedy with Jacques Cartier on his voyage to Newfoundland in the 16th century, yielded 200 mg of vitamin C per 100 g of leaves (Carpenter, 1986). Although infusions of fresh spruce leaves contained 14 mg/100 ml, after fermentation the vitamin content virtually disappeared (Hughes, 1975). Cider, i.e. fermented apple juice, was also recommended, but depending on how it is made it contains little or no vitamin C.
In 1747, James Lind carried out his famous controlled clinical trial on board a British naval vessel to prove conclusively the power of lemons and oranges over popular remedies to cure matched scorbutic cases on a scorbutic diet. Twelve sailors with scurvy were divided into two-man teams, and each received a different antidote: cider, diluted sulfuric acid, vinegar, sea water, various drugs, or 2 oranges and a lemon a day. Those receiving the oranges and lemons improved after 6 days. Those receiving the cider were the next best at the end of 2 weeks. His conclusion was "that oranges and lemons were the most effective remedies for this distemper at sea" (Hughes, 1975).
The main problems with oranges and lemons were storage and transportation. The pressed juice was used as an antiscorbutic. After 1875, however, there was a loss of faith in lime juice in naval circles since most of the vitamin C was lost largely as a result of long periods in settling tanks and the pumping of juice through copper pipes (Carpenter, 1986). Evaporating 800 ml juice down to one-tenth of this volume to produce "robs of oranges/lemons" resulted in the loss of one-half of the vitamin. When the rob was stored for a month at room temperature, less than one-seventh of the original vitamin remained (Hughes, 1975).
There have been a number of theories about the cause of scurvy since the 18th century, e.g. food poisoning, infection, protein deficiency, and a deficiency of potassium and/or iron. These theories in turn were a reflection of the methods used to prevent and cure scurvy.