Food Science

Nutrients – what do we need?

What is food?• Something that living organisms take into

their bodies to:–provide us with energy –help us to develop– to keep us warm–prevent disease –Live

• We need food for all these processes

The Magnificent 7 (food substances)

Carbohydrates

• Most common source of energy

• Found in breads, potatoes, cereals

and pasta

• Sustained energy

• If not used up – gets turned into fat

• 4 – 5 portions a day

Fibre• Needed to maintain healthy digestive

system – not strictly a nutrient• Found in

– wholegrain breakfast cereals– wholegrain, granary or seeded

breads– brown rice– fruit and vegetables– beans and pulses– nuts and seeds

Minerals• Chemical elements needed to

keep you healthy• Maintain immune system• Helps cells and organs do their

jobs• Found in:

– Fruit– Vegetables

Vitamins• ‘Vital’ for life, can’t live without them

• Only tiny amounts needed

• Vitamin A, C, E

• Found in:–Fruit–Vegetables

Fat• Supplies energy• Insulates us• Fuel reserve• Needed as building blocks• Found in:

– Meat– Olive oil– Butter– Milk– Nuts

• To much is not good

Proteins• Needed to build and

repair new cells• Builds muscle• Found in:

– Meat and fish– Dairy products– Soy products– Nuts and pulses– Eggs

• 12 % of daily intake

Water• Between 50-60 % of your body is water• Needed for healthy body• Should drink 6 – 8 glasses a day• Found in:

– Fruits (watermelon)– Vegetables (cucumber)– Taps

• Need more when exercising• Brain is 80% water, being dehydrated effects your

concentration

A balanced diet• Each food should be eaten in the right

proportionsFruit and vegetables Bread, other cereals and

potatoes

Meat, fish and alternatives

Milk and dairy foods

Foods containing fat

Foods containing sugar

Food scientists

• Investigate foods to determine which nutrients they contain

• Test for:– Carbohydrates – starch and glucose– Fat– Protein

Carbohydrates

• Starch– Long chain carbohydrate (complex)

• Glucose– Smaller, usable molecule

• Two tests:– Benedicts for glucose– Iodine for starch

Testing our food: Starch

Testing our food: Glucose

Testing for Fat

• Fat – emulsion test

Testing for Protein

• Biuret test for protein

• Complete a spider diagram entitled Nutrients showing– Each of the seven nutrients– What we need them for– An example of each