The mineral composition of apples. Composition in relation to disorders of fruit imported from the southern hemisphere

Calcium concentrations in individual apples grown in Australia, South Africa and New Zealand, and affected by lenticel blotch pit, were low (1.5–3.1 mg per 100 g fresh weight). Bulked samples of Cox's Orange Pippin fruit grown in 19 orchards in New Zealand and imported in 1971 and 1974 had, on average, lower concentrations of phosphorus and nitrogen than is usual in this variety grown in England. Comparisons of concentrations of calcium and the incidence of bitter pit in these samples indicated a similar threshold of 5.5 mg per 100 g above which the disorder was unlikely to occur and which is similar to that found for bulked English Cox apples. Although bitter pit symptoms were visible externally in many apples, about twice the number were found to be affected by the disorder when cut.