Protein

• protein is made up of:

  carbon, hydrogen, nitrogen, oxygen, phosphorus and sulphur.
• how many essential amino acids:

  -20 essential amino acids

  -10 essential in children

  -8 essential in adults
• essential amino acids:


  are ones that can't be made in the body so have to be supplied by food sources.
• non-essential amino acids:


  are ones which most can be made and digested in the body
• chemical structure of protein:

  
• amino acids- condensation reaction 


  join others by peptide bonds. They are formed when the amino group of one amino acid reacts with carboxyl group, with the loss of one water molecule. which is called a condensation reaction .
• protein complementation 


  is when two LBV foods are eaten together to obtain all the essentail amino acids needed in the body.

  For example, beans on toast
• Denaturation of protein molecules:

  heat

  mechanical

  PH (acid levels)

  all disturb and breaks the bonds that hold the molecules together and causes then to unravel and lose the structure.
• types of protein 


  -collagen is in meat and fish mainly in connective tissue.

  -Actin is in meat and fish mainly in muscle tissue.

  -Albumin is in egg white
• LBV - low biological value foods 


  are ones which don't contain all the essential amino acids

  e.g. seeds, nuts, vegetables and grains.
• HBV - high biological value foods


  are ones which contain all the essential amino acids for the body.

  e.g. meat, fish, dairy products, eggs and quorn.
• function of protein 


  primary: repair and growth. repair muscle tissue and growth of hair and nails.

  secondary: is energy
• excess of protein 


  can damage kidneys and liver
• deficiency of protein 


  stunted growth in children.

  slower repair of cuts and wounds.

  Have a low immune system and get ill easily.