24.5.09
Chemi what?
Have u ever wondered what happens to the ingredients when they are cooked?
For an instance,the pancake.
What happens when the batter is placed in the hot pan?
What changes occur within?
As you know,cooking is one big chemical reaction.
Obviously,there will be chemical changes that's brewing in the batter when it is pan-fried.
So what are the chemical changes?
Firstly what is pan-frying?
It is a dry heat cooking method that is characterized by the use of less cooking oil as compared to deep frying.The oil used,at most,cover the food to be cooked only half way.It exposes the topside which allows some moisture loss and contact with the pan bottom creates greater browning on the contact surface.The heat eventually melts the fat,gelatinizes the starch,coagulation of flour and browning reactions like Maillard reaction and Dextrinisation.
Maillard reaction is a chemical reaction between a protein and a carbohydrate.It requires heat and it is a form of non-enzymatic browning.In context to pancakes,the protein group comes from the egg and milk whereas the carbohydrate group comes from the flour.
Dextrinisation is the browning process produced by dry heat on starch. The starch molecule breaks down into dextrin.
As we know,pancakes are made from a batter consisting of
flour,eggs,a pinch of salt and milk which is then pan-fried.
Flour consists of two proteins known as gliadin and glutenin.This two proteins form a gluten network upon hydration and kneading.The higher the protein content in the flour,the more water will be absorbed.Upon hydration,it forms a complex intertwined network(gluten network) which is filled with water in the spaces.
As wholemeal flour contains a higher amount of protein content,it gives a more characteristic texture like being more tender and less chewy as compared to plain flour
Eggs are the connectors to all ingredients.When the batter is heated,egg white proteins in it bounce around and slam into surrounding water molecules.It breaks the weak bonds that keep the protein curled up.New chemical bonds are form,these bonds connect one protein to another.Eggs also acts as a tenderizing,flavouring and emulsifying agent in this context.
Salt are natural flavour enhancers.It also affects the pancake from the moment its added in the batter.It slows down chemical reactions that are happening in the batter and also makes it a little stronger and tighter.
Milk has different roles in the batter.It functions as water(solvent),fat binder,incorporation of air,viscosity,gelation,nutrient content and flavour.
http://books.google.com.sg/books?id=Nze8hLpVmasC&pg=PA296&lpg=PA296&dq=effects+of+milk+in+baked+products&source=bl&ots=Ai-C0Bmc-G&sig=aBcvc2buZZ0mA3sX9jKkI3SVqtk&hl=en&ei=8aQZSqaJJYaG6wPtq5mXCg&sa=X&oi=book_result&ct=result&resnum=1#PPA293,M1
Posted at 22:21