Task 2: Function Properties of Carbohydrates- Dextrinisation

In your own words, summarise what you have learnt about the chemical and physical properties of carbohydrates in relation to dextrinisation and caramelisation. As part of your summary comment on something that you did not know or understand before now or something that you still don’t understand and want to know more about.

 You may use the following ONLY as a guide if you are unsure what to comment on.

•  The difference between dextrinisation and caramelisation
•  Chemical/physical changes that occur.
•  The experiments and how they helped your understanding.
•  Usefulness of dextrinisation in food processing.

Just saying, that cooking and applying knowledge of food science through conclusion questions is so much easier then learning through power points and notes from textbooks! We did these experiments focusing on the functional properties of carbohydrates- better worded as we got to make chocolate chip cookies, toffee, and honeycomb! YUM YUM YUM!

 

When we were doing this experiment at school, a lot of people were finding it hard, burning there sugar in the pan turning it black and the smell was disgusting- this was hard to understand for me, because I have been making these, and doing these specific 'experiments' in the kitchen my whole life. When they couldn't understand why when you added the bicarb soda(the acid) to the sugar mixture is aerated and created a gas, but then traps itself inside the mixture forming a fluffy honeycomb mixture- I was so confused. I mean why did I understand this but they didn't? I'm usually the quiet one that doesn't share my opinions about things in class. But I knew that I was one of the most knowledgeable person when it came to the practicals in the kitchen.

 

So when reading through my notes about this experiment, I came to the conclusion that the things we learn in this class helps me so much in my career- not only is learning about all these chemical structures hard, but its also really interesting. My aspiration of becoming a chef, has only increased my interest in learning about food science, and the chemistry of food, and not only can I help my peers almost every time when they need it, I can better my knowledge and understanding of this subject-which is really exciting! 

So lets get down to business with the differences between Dextrinistation and Caramelisation..

Firstly, lets do definitions

Dextrinisation is prettymuch where things that have starch in them become brown through heating. The more complicated definition is the process in which starch breaks down into dextrins. For example, you know when your toast goes brown and burnt if you toast it for too long? Thats because the starch molecules have broken down into dextrins, and because of the amount of exposure to the dry heat in the toaster and the temperature, it burns pretty easily if you don't keep an eye on it!

Where as Caramelisation is where things that have sugar in them go brown when coming in contact with heat. I know your reading this going.. what is this chick on, she just said that? So yes, its pretty much the same method as dextrinisation in the form of heat application to either starch or sugar and making it brown. The difference is the starch or the sugar. The degree of caramelisation that occurs is determined by the length of heating time, the addition of other ingredients(eg, fat, bicarbonate soda), the type and amount of sugar used and the temperature at which the sugar reaches.

So remember if it has starch- its dextrinisation
and if it has sugar in it- its caramelisation or even crystallisation!

The usefulness of dextrinisation in food processing is pretty simple to explain, as dextrinisation is responsible for bread turning brown during toasting(as mentioned before), the formation of the brown crust you see on baked bread, pastries and baked starchy vegetables such as potatoes, sweet potatoes etc, baked breakfast cereals and the delicious brown gravies for your beautiful baked dinner. Did you know that dextrins are also used as a colouring agent, and also a sweetening agent?

As for Carmelisation, its used for the maiking of all your yummy cakes, baked products, ice-cream, honeycomb, creme caramel(one of my absolute favourites!) and pretty much all confectionery products.

Just because I mentioned creme caramel, I'll leave you with this pretty one, with whipped cream on the top, surrounded by a sugar cage(made of toffee-get it, cause we we're talking about making toffee) I think I might make one of these for dessert tonight!