“Homemade food colorings” experiment

The word “dyes” of­ten calls up as­so­ci­a­tions with some­thing ar­ti­fi­cial and harm­ful, but this doesn’t have to be the case. In this ex­per­i­ment, you will learn how to use veg­eta­bles to make safe, nat­u­ral dyes.

Safe­ty pre­cau­tions

This is a safe ex­per­i­ment. Ob­serve safe­ty rules when work­ing with boil­ing wa­ter and heat­ing de­vices.

Reagents and equip­ment:

• 200g spinach;
• 2-3 beets;
• 100g onion skin;
• glass jar;
• grater;
• fry­ing pan;
• stove;
• 1 ta­ble­spoon of 9% vine­gar;
• spat­u­la;
• fun­nel;
• ban­dage or gauze;
• knife;
• cut­ting board;
• la­dle;
• 100mL 40% ethanol so­lu­tion.

Step-by-step in­struc­tions

Beet­root dye: grate 2-3 beet­roots, put the pulp in the fry­ing pan, add 200mL wa­ter and a ta­ble­spoon of 9% vine­gar, and stew for 15 min­utes. Fil­ter the stew through the fun­nel with gauze. Spinach dye: put 200g fine­ly-chopped spinach in a fry­ing pan and add 100mL 40% ethanol. Stew for 15 min­utes. Fil­ter through the fun­nel with gauze.

Onion skin dye: pour 500mL boil­ing wa­ter over 100g onion skin and leave for 15-20 min­utes. Fil­ter through the fun­nel with gauze. The dyes are ready!

Pro­cess­es de­scrip­tion

Put boiled eggs in the dye so­lu­tions for 30-60 min­utes. No­tice that the eggs change col­ors. Spinach leaves con­tain a green pig­ment called chloro­phyll, which dis­solves well in ethanol. Onion skin con­tains a pig­ment called beta-carotene, which gives the skin its gold­en col­or and dis­solves well in hot wa­ter. Beet­root con­tains a mix­ture of dif­fer­ent pig­ments that col­or it red. They dis­solve well in wa­ter but de­com­pose when heat­ed for long pe­ri­ods of time. Some vine­gar must be added to pre­serve their col­or. Eggshells main­ly con­sist of cal­ci­um car­bon­ate, which has a por­ous struc­ture that can eas­i­ly ab­sorb dyes.