Phytate, Calcium, Iron, and Zinc Contents and Their Molar Ratios in Foods Commonly Consumed in China

Abstract

A total of 60 food samples commonly consumed in China were analyzed for phytate using the anion-exchange method and for calcium, iron, and zinc using atomic absorption spectrophotometry. The foods analyzed included those based on cereal grains and soybean. Phytate contents expressed on a wet weight basis ranged from 0 for foods made from starches to 1878 mg/100 g for dried stick-shaped soybean milk film. The calcium contents were between 2.08 mg/100 g for ground corn and 760.67 mg/100 g for diced fried soybean curd. The lowest values of iron and zinc were 0.04 mg/100 g for Panjin pearl rice cooked with discarding extra water and 0.08 mg/100 g for potato and bean starches, while the highest values of iron and zinc were observed in dried stick-shaped soybean milk film. Although many foods were relatively rich in calcium, zinc, and iron, many also contained a higher level of phytate. Of the 60 food samples, 34 foods had a phytate/calcium molar ratio >0.24, 53 foods had a phytate/iron molar ratio >1, 31 foods had a phytate/zinc molar ratio >15, and only 7 foods had a phytate x calcium/zinc >200. Phytate in foods impair the bioavailability of calcium, iron, and zinc, which to some extent depends upon food processing and cooking methods.

Effect of soaking and sprouting on iron and zinc availability in green and white faba bean (Vicia faba L.)

“…The same result was observed by Ma et al (2005) who reported that Fe concentration of the faba bean grains ranged from 3.0 to 11.3 mg/100 g. The Zn concentration ranged from 1.1 to 4.4 mg/100 g. After soaking, the Fe content of the faba bean was significantly lower than raw faba bean (P<0.05). After soaking, the losses of Fe contents were 28.2 and 39.8 %.…”

“…They are relatively inexpensive compared to meat foods and they have a high carbohydrate content (50-65 %). In China, plant foods provide at least 50 % of the dietary energy and nutrients, and faba bean is one of the most important legumes (Ma et al 2005). Faba beans are a good source of dietary minerals, such as phosphorus, potassium, calcium, sulphur, zinc and iron.…”

Iron intake does not significantly correlate with iron deficiency among young Japanese women: a cross-sectional study

“…The remaining total Fe intake was assumed to be non-haem Fe. Because we had insufficient information on the phytate content in Japanese food, we used dietary composition data from other countries (32)(33)(34)(35) . Bioavailable Fe is the amount of Fe actually absorbed and utilized in the body, and is determined by several factors, including intake of phytate, Ca, vitamin C, meat, fish, tea and coffee and the individual's Fe status.…”

Efeito do triacilglicerídeo de cadeia média, da fibra e do cálcio na disponibilidade de magnésio e de zinco pelo método in vitro e metodologia de superfície de resposta

“…A forma química dos minerais e fibras contidas em alimentos ou em dietas, principalmente na presença de oxalatos e fitatos, impede a absorção de ferro, zinco, cobre e cálcio. Por isso, em dietas enterais, existe a preocupação de serem adicionados substratos que não venham a impedir a biodisponibilidade de nutrientes, levando pacientes à desnutrição de minerais essencias para as funções metabólicas do organismo humano [25][26][27] . Isso pode interferir em outros minerais e provocar deficiências múltiplas nos indivíduos.…”