Starch boiled with : acids ... shows an adhesiveness to the tongue; when mixed with water it should give a white milky fluid, without any particles of dirt floating on the top, and should settle ...

The green parts contain chlorophyll and photosynthesise to make starch ... when placed in a beaker of hot water. In this experiment you need to place a leaf in boiling ethanol to decolourise ...

Unfortunately, this process is incredibly inconsistent, and will vary with your water to pasta ratio when boiling the noodles—and even then it's usually around 1% when 2% to 3% starch is needed ...