The Hangi Essays - Physics, Heat Transfer, Thermodynamics

The Hangi How does the construction of the Hangi cook the food with it? Introduction: The Hangi is a traditional Maori method of cooking food. Food from a Hangi is cooked underground by red-hot volcanic rocks and steam, which condenses onto the food, therefore cooking it. To make a hangi , a pile of wood is lit under the ground, heating up the light and easy to heat volcanic rock red hot. In modern Hangi , wire baskets filled with food are put inside the ground along with the volcanic rocks and covered with a wet cloth and soil dug up from the ground. The very hot steam created underground with the food has no other way of escaping, so it condensed onto the food, transferring its heat onto it. After 3 hours, the food should be completely cooked. Paragraph 1: Construction of Modern and Traditional Hangi Before the Introduction of metals and wire, the Maori only had Hangi to cook their food. In traditional Hangi , the food is laid out onto bark, large leaves, clean sticks, large leaves and other sorts of vegetation. These methods carry a whole range of uses including keeping the food clean, reduce burning, and to keep direct contact with the super-heated rocks to an absolute minimum. Some tribes used a carved wooden bowl called " Kono " to cook food by placing their food inside, then putting hot rocks on a liquid base to heat up the liquid, therefore cooking the food inside of it. The traditional Hangi cooked a variety of food such as fish, birds, other land animals, and vegetable leaves such as Puha , Kokihi and Kohetake . This method of cooking food was not however mainly used for cooking food but also favoured by Tohunga (Expert Practitioners) for making medicines and remedies by heating up leaves, bark and other organic matter. The introductio n of cooking vessels such as pots and pans ended the daily use of Hangi to cook food. This is because Hangi take a lot of time, preparation and planning to go into it, while the use of a pot or pan can make that process much faster.In modern Hangi , the leaves that were used are likely to be substituted with aluminium foil and metal baskets made of wire. The baskets prepared with food wrapped with aluminium foil are carefully placed inside the stones, with cabbage leaves on the bottom of the basket to prevent the basket and aluminium foil from burning. The food is then covered on the top with a wet cloth, then sprayed with water to create extra steam for the Hangi to cook on. Then a mound of Earth is placed on top of the Hangi is a way which traps the steam and heat from escaping. The food is then cooked and ready to eat in 3 to 4 hours. The modern Hangi , in my opinion, is better that the traditional Hangi for a number of reasons. Firstly, the tr aditional Hangi uses material they find in the bush such as leaves, bark and sticks to put their food over. This might be a health hazard to the people that eat the food as dirt and other debris such as ash from burning objects like wood, or the dirt finding a way to get into and contaminate the food. Also, people might get burn in the making of the fire, especially in the very hot conditions inside and near the Hangi . A modern " Hangi Machine" is available for purchase and it is a much safer way to cook food. With this Hangi machine, you are able to cook kai very easily, with less preparation and danger. But I believe the Hangi Machine undermines the whole "traditional cuisine" part of the Hangi . Paragraph 2: Types of Heat Transfer and Open and Closed Systems Liquids and Gases expand when they are heated. This is because the particles in the liquids and gases vibrate faster and faster as they get hotter, causing them to move. They also lose energy when they are cooler, slowing the vibration of the particles down, which makes the particles slower than when the liquid and gases are