Food speed lesson 3 run throughs 2 Breaks

And how about eating? We need a healthy diet, this contains – Carbohydrate – Protein – Vitamin – Mineral – Water – Fat – Fibre

Carbohydrates are chains of identical sugar molecules. Enzymes called carbohydrases (amylases) break the chemical bonds, making glucose molecules carbohydrase long carbohydrate molecule sugar molecules Enzymes and carbohydrate digestion

5/7 is Carbohydrate

Starch Test Put a sample of food in the bottom of a test tube. Add a drop of iodine solution. What colour change will there by if starch is present.

Glucose (From carbohydrates) … for energy

Test for Glucose Put a sample of your food stuff in a test tube. Add five drops of Benedict’s solution. Heat gently in a water bath. Benedict’s solution will turn from in the presence of glucose.

Proteins are made up of different amino acids. There are 20 different types of amino acids. Enzymes called proteases break down proteins. These enzymes work in an acidic environment to break proteins into smaller amino acids. protease long protein molecule amino acid molecules Enzymes and protein digestion

Whey PROTEIN to build muscle

Test for Protein Put a sample of your food stuff in a test tube. Add five drops of Biuret’s solution. Carefully shake the test tube. Biuret’s solution will turn from blue to purple

1/7 is Protein

Fats Store energy and used in cell membranes to help stop water moving through

Where do we find fats Fats often coat foods Like oil on chips

Fats are digested in two stages: Firstly, bile breaks fat into smaller droplets. This is called emulsification. Secondly, the enzyme lipase breaks each fat molecule into the smaller glycerol fatty acid molecules. bile lipase + fat molecule glycerol fatty acids Enzymes and fat digestion

Test for Fats Add Ethanol and shake Add distilled water If fat is present a milky-white emulsion (layer is formed)

1/7 is Fat

Carbohydrates: Bun, Chips (Lots of the meal!) Protein: Meat (Not much.. 1/7 th ?) Fat: Coating the chips and meat … 1/7 th ?

Vitamins and Minerals What else?

Vitamins Are made of many different types of elements Key Vitamins are C and D Vitamin C – Dissolves in Water and found in fruit – Problems of not enough include falling out teeth Vitamin D – Dissolves in Fat – Problems of not enough include soft bones

Vitamins and Minerals in the salad

Vitamin C To stop you losing your teeth to scurvy

Vitamin D Stops rickets Bendy bones

Minerals Minerals are elements Key minerals are Iron and Calcium Iron – Found in meats, – used in blood. You could also just go and lick some iron. Calcium – Found in dairy products (milk, cheese) and fish – Used in bones, teeth, blood clotting and muscles

You need minerals and vitamins Iron in the blood To carry oxygen

No calcium can cause problems

Water Facts 70% of the human body Humans lose around 1.5 litres per day – In urine, faeces, sweat and breathing Re-absorbed in drink, food AND RESPIRATION Losing 5% water = unconsciousness Losing 10% water = death

A Water saving methods The Kangaroo Rat Method Don’t drink and absorb all water in kidneys. RESPIRATION EQUATION Glucose+Oxygen => Energy+CO2 + WATER

Fibre Allows your faeces to pass through Found in things you don’t digest (think of your faeces after eating sweetcorn!) Without it you look like this

Things can be added to food Food Additives make things look better,

Make it last longer

Even change taste

Fortifiers make food stronger Iron in cereals!!!

Some things are left over.

These are residues They could be hormones for growth

Fertilizers to add minerals

Or even pesticides To kill bugs

Food residues These can also be eaten in food.

Food problems

Too much = problems Rubbing joints (arthritis) Type II Diabetes – No Insulin Heart attacks

Too little = problems too The body doesn’t eat food so it eats itself – Atrophy Hair loss Reduced immune system

How to work it out BMI Mass (kg) Height x Height (m)