10 BIODIVERSITY, OCCURENCE OF ORGANISMS AND THEIR EXTINCTION IS THE RESULT OF EVOLUTION

Activity 3: Rosehip tea

WORKSHEET Workshop


The teacher collects and dries rosehips (or buys them dried in a herbal pharmacy). He/ she puts the rosehips into two beakers and pours hot water from the kettle into the one of the beakers only and allows it to infuse (he/she makes infusion). The teacher pours hot water into the other beaker too but boils the contents on the stove for about 25 min (he/ she makes rosehip tea). Pupils observe the appearance of the contents of both beakers at the beginning of the experiment and 25 minutes later. The contents of the beaker, which has not been boiled is clear, slightly coloured and contains vitamin C. The content of the second beaker has become intensively orange as the carotenes, which are dyes that give rosehips the orange color, are released by boiling. However, vitamin C is destroyed with a long boil. After it has cooled down, pupils can taste the contents of both beakers to try their differences.