EDWARD'S LECTURE NOTES:
More notes at http://tanguay.info/learntracker
C O U R S E 
The Science of Gastronomy
Prof. Lam Lung Yeung, The Hong Kong University of Science and Technology
https://www.coursera.org/course/scigast
C O U R S E   L E C T U R E 
The Transfer of Heat Through Foods via Conduction
Notes taken on August 1, 2013 by Edward Tanguay
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conduction
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thermal energy is transferred from one molecule to the nearby molecule by means of a collision, there is no relocation of molecules
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during cooking, heat is transferred from the outside to the center of a solid piece of food by means of conduction, e.g. steak
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cellular structure of food impedes heat transfer
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rate of heat transfer is determined by
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thickness of food
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overall shape of food
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temperature of pan
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amount of time heat is applied
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how much energy is need to heat up food?
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(mass) (specific heat capacity) (change in temperature)
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heat capacity
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the measurable physical quantity that specifies the amount of heat required to change the temperature of an object or body by a given amount
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water has a very high heat capacity
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you need a lot of energy to heat up water
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in general, the higher the content of water in food, the slower it will heat up
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water also holds heat longer, which is why when you burn your tongue it is usually on parts of food that contain a high amount of water, e.g. a tomato or cheese on a pizza, but probably not the crust
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metals have a low heat capacity
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you don't need a lot of energy to heat up metals
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heat conductance
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how fast heat flows through the food
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silver and copper
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high conductance, low heat capacity (heat up quickly)
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water (and fish and meat)
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low conductance, higher heat capacity (heats up quickly, i.e. has a higher capacity to hold heat)
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applications
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stone grill
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stone can store a lot of energy and gradually pass out the heat
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Teppanyaki grill
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style of Japanese cuisine that uses an iron griddle to cook food
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widely used to cook food in front of guests at restaurants