Potatoes calcium content

McGuire, R. G., Kelman, A. (1984). Reduced severity of Erwinia soft rot in potato tubers with increased calcium content. Phytopathol., 74,1250-1256. 

Potatoes are an excellent source of carbohydrates and contain significant amounts ofphosphorus, potassium, calcium, and vitamins, especially vitamin C. Potato protein content, at over 10%, is relatively close to that of wheat flour (11%) also, thanks to their lysine, methionine, cystine and cysteine contents, potatoes are a valuable supplement to cereal proteins. For instance, potatoes provide a significant source of proteins (10-15% of total requirements), a major source of vitamin C, an important source of energy, and also minerals like iron and other vitamins such as thiamin, nicotinic acid, riboflavin, and pro-vitamin A (p carotene) (Salunkhe and Kadam, 1991). 

There are significant differences in maj or and trace mineral contents amongst different genotypes of potato (Randhawa et al., 1984 True et al., 1978). Potassium levels varied the most and manganese the least. In a study of 74 Andean landraces, the iron content ranged from 29.87 to 157.96 p,g/DW, the zinc content from 12.6 to 28.83 p,g/g DW, and the calcium content from... 

Potatoes are a poor source of minerals, except for the abundant element potassium the calcium content is particularly low. The phosphorus content is rather higher, since this element is an integral part of the potato starch molecule, but some 20 per cent of it is in the form of phytates (see p. 115). 

Potassium, phosphoms, calcium, and magnesium concentrations changed with irrigation and fertilization in physiologically mature tubers (Ilin et al., 2002). The total concentration of iron, calcium, and zinc increased with application of fertilizers whereas the content of phosphoms and molybdenum was reduced (Bibak et al., 1999 Frossard et al., 2000). The wide range of mineral content reported in potatoes may not only be due to genotype and environmental factors, but also sampling issues. 

Cieslik, E., Sikora, E. (1998). Correlation between the levels of nitrates and nitrites and the contents of potassium, calcium and magnesium in potato tubers. Food Chem., 63(4), 525-528. 

Table XII. Calcium and Magnesium Content of Potato Tubers...

Mushrooms are high in water content (90%) and low in calories (28 to 35 kcal per 100 g). They contain atrout 20% more protein than potatoes, but they furnish less than half as many calories. Furthermore, they are very low in calcium, vitamin A, and vitamin C moderately low in thiamin and riboflavin and a good source of phosphorus, potassium, and niacin. However, many of the nutrients that are lacking in mushrooms may be provided by green leafy vegetables and milk products, which go well with the fungi. 

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