Brain scanner to foil meat cheats

1 	Use a textbook to find out how NMR spectroscopy works. 

	a) What type of scanning radiation is used? 
	b) Why must the sample be placed in a magnetic field? 
	c) What types of atoms are detected by this method?

2 	What was this method first used for in hospital?

3 	Why do you think such a sophisicated analytical method is needed to find 	out something as simple as the water content of meat?

4 	What do you think are the disadvantages in having an extra-high water 		content in meat on sale in the shops?

5 	Why does food which has been frozen and then thawed often have a different 	texture from fresh food?