Science Fact : Tapai Pulut

What Is Tapai Pulut?

The fermented glutinous rice (Tapai Pulut) is a popular Malaysian favorite, normally eaten as a dessert. Tapai Pulut is made by fermenting glutinous rice (Oryza sativa glutinosa). It is served at functions such as festivals and weddings within the Malay community of Peninsular Malaysia. Tapai Pulut tastes sweet with a pleasant aroma and is wrapped with rubber tree leaves or banana leaves. 

What Do I Need?

 

Glutinous Rice                          

 

Rubber Tree Leaves                             

 

 Yeast

What to do?

1. 
   

   First, wash the glutinous rice and soak it overnight.
   2.      Next, cook the glutinous rice.
   3.      When the rice is cooked, cool it.
   4.      Pound the yeast. Sprinkle it on top of the cooked rice.
   5.      Turn the rice over and sprinkle yeast on it.
   6.      Put the rice in air tight container and let it ferment for 2 days.
   7.      After 2 days, the rice is ready to be wrapping in rubber tree leaves.
   8.      Keep it in refrigerator.

What’s Going On?

1.            Yeast carries out both aerobic respiration and anaerobic respiration.
   2.      Anaerobic respiration in yeast cells is called fermentation.
   3.      During fermentation, yeast secretes the enzyme zymase which hydrolyses glucose in the absence of oxygen to form ethanol, carbon dioxide and energy.
                                                    
   Glucose           → ethanol + carbon dioxide + energy
   
   
   
   
   4.      The enzyme zymase by the yeast speed up the fermentation process.
   5.      In the fermentation process, only a small amount of energy is released. A large amount of energy is still stored in ethanol as chemical energy. This is because glucose is not completely broken down in anaerobic respiration.
   6.      The products of fermentation such as carbon dioxide, is used as a raising agent in baking bread while ethanol is used to produce alcoholic drinks such as wine.