A similar experiment is included in the “Chemistry of drinks” set from the MEL Chemistry subscription.
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In this experiment, you’ll find out how to make curd at home from just two ingredients.
Observe safety rules when working with heating devices
Warning! Only under adults supervision.
Reagents and equipment:
* 1 liter of cow’s milk;
* 5% calcium chloride solution (15 ml);
* hot plate;
* glass container.
Pour milk into a saucepan and heat to a temperature of 40 С (104 F). Then add the calcium chloride solution and heat for 20 minutes. Keep stirring the mixture constantly and don’t bring it to the boil. Watch the milk curdle.
Cow’s milk is a dispersion system–a water emulsion consisting of drops of fats, sugars and proteins bonded with mineral components. A liter of milk contains 30-35 g of proteins. When a coagulant is added (for example, calcium chloride solution), the balance in the system is disrupted and the proteins curdle (coagulate). So we get curd. Incidentally, in Quebecois cuisine, this product is called caillé and is considered to be a national dish.