Nutrient and mineral composition of dried mamaki leaves (Pipturus albidus) and infusions

Mamaki, Pipturus albidus, is currently one of the few native Hawaiian plants suitable for herbal tea preparation. This study reports the nutritional composition and mineral content of dried mamaki leaves and infusions. Three varieties and two sub-varieties, namely “hybrid purple”, “green”, “purple sub-variety 1”, “purple sub-variety 2” and “panaewa”, of mamaki were harvested in winters and summers over a 3-year period. Statistical analyses showed macronutrient values in dried mamaki leaves harvested in summer were significantly different from those in winter. The elemental values of phosphorus, magnesium, sodium, boron, copper, iron, manganese and zinc were also significantly different between the two seasons. Dried mamaki leaves contained higher amounts of ash, protein, fat and total fibers when compared with various commercial teas. Copper and iron levels in infusions from the leaves harvested in summer were significantly higher from those in winter. Phosphorus, potassium, sodium, boron, iron, manganese, and zinc values in steeped infusions of whole, ground, and crushed leaves were significantly different from each other. The dried leaves and infusions both contained the highest amount of calcium when compared to those in other commercial teas. The high calcium content found in infusions make the mamaki leaves a valuable commodity.