Objectives :
Revision – how is carbohydrate structured
Define dextrinization
Define caramelisation
Define gelatinisation and what can affect it
Tasks:
Watch the lesson videos
Fill in the gaps
Copy out the tables
Answer questions
(Optional and be careful) Make spun sugar or bonfire toffee
On you glossary page please write out the following terms:
Dextrinisation – when dry heat turns starch brown.
Caramelisation – when heat (moist or dry) changes the colour, flavour, and texture of sugar.
Gelatinisation – when moist heat is applied to starch. The starch gains swell and burst, releasing amylose, which thickens the mixture around boiling point.
Please watch the lesson video part 1:
Fill in the gaps on dextrinisation using the words below, the worksheet is on the learning platform (or copy it out):
Dextrinisation:
·When foods contains starch such as ……….. , …………. , ………… , ………….. and …………. are cooked by …………… ……………… (grilling, baking, toasting), they develop a ……………….. colour on the outside.
This is partly due to the effect of heat on the ……………….. molecules, which break into smaller groups of ………………… molecules called ………………….. .
……………………………… is the name given to this process.
Carbohydrates are made from …………………… , …………………………. and ………………….. . When you ……….. them you have gone past the dextrinization stage and the ………………… and ……………….. have been driven off by the heat and you are left with ……………….. .
Please watch the lesson video part 2:
Please write up the stages of caramelisation:
1. Sugar that is used in cooking (sucrose) is a disaccharide made from glucose and fructose.
2. When sugar is heated, it firstly melts.
3. Then it forms a syrup and starts to boil.
Answer the question:
Why does the colour of the sugar change during caramelisation? (please write it out in a full sentence)
Hint: Think back to why your toast changed colour…
Complete the table below (the answers are in the video above):
Please watch the animation:
Fill out the gaps on gelatiniation:
1. When starch ………………. are put into water and then heated, at about ………⁰C they start to absorb the water, which causes them to …………. up and get bigger.
2. It is important to s…….. the sauce r…………….. as it is heating up, to prevent the starch granules from staying at the ………………… of the liquid, where they would swell up, stick together and cause the sauce to have a l……………… t……………… .
3. At about 80⁰C, the starch granules are so swollen they start to burst and release ……………. ………………….. into the surrounding liquid.
4. These released starch m………….. form a 3D network that t………. water molecules and stops them moving around so much.
At …………. point the sauce completely thickens, the sauce should be h……….. for a few minutes to make sure all the starch is c……………. .
This process is called ……………………..
5. As the cooked sauce cools down, the starch molecules start to form ……………. chains and the water molecules stay ………………. inside them, so the sauce gradually becomes a solid …………..
Copy out the table:
Please send me a picture/the word document of your work by 19th May
Feedback: I will say thank you for completing the work (again keep up the hard work - this will all be super useful for NEA1)
FAQs: Don't forget I'll be on my email (kconnett@taptonschool.co.uk) to instantly respond to questions between 12-1pm on Monday. If you can't get on to email at that time, please email your questions over the weekend and I will add it to the FAQ section here.