Mineral elements and related antinutrients, in whole and hulled hemp (Cannabis sativa L.) seeds

Abstract

Hemp (Cannabis sativa L.) seeds have been traditionally used as food and their consumption is increasing nowadays. They have a remarkable nutritional value, but scarce information is available about mineral elements and their bioavailability. The objectives of this study were to determine the mineral element and phytate contents of eight different varieties of whole hemp seeds and commercial hulled hemp seeds. Phosphorus was the most abundant mineral element with higher content in hulled seeds (1.1 g/100 g) than whole seeds, as well as potassium, magnesium, and zinc. Calcium, manganese, and copper contents were higher in whole seeds. Iron content (8 mg/100 g) was similar in whole and hulled seeds; while sodium was below 5 mg/100 g. Phytate was abundant in hemp (especially hulled) seeds (4 g/100 g), and could compromise iron and zinc absorption (phytates/Fe and phytates/Zn molar ratios above 20 and 15, respectively), as well as involve poor phosphorous absorption. These seeds represent a valuable contribution to manganese (>5 mg/100 g) and copper (>1.4 mg/100 g) intake, approaching 100% and 50%, respectively, of daily NRVs, with a serving size of 30 g. Hemp seeds are an apparently excellent source of minerals, although phytates content should be taken into account to properly interpret nutritional claims.