Discussion in 'Supporting Biology' started by jan, Jul 1, 2019.

  1. jan


    Morning All, we are starting food tests again but i am always stumped for foods that work well.
    Can anyone give me ideals for foods that will work for each food group. Thanks
  2. We use:
    Instant mashed potato mix
    Powdered milk
    Powdered egg white
    Whey powder
    Ann Chinnery likes this.
  3. This is what we use:
    Egg whites
    Pure fruit juices
    Ann Chinnery likes this.
  4. We use the above plus cake mix as a 'mystery substance' once they have done all their standard tests.
    Ann Chinnery likes this.
  5. snap and suet for fat
  6. (ready grated) cheese, banana, oil, egg albumin solution (made up from powder), pumpkin seeds, milk, bread and raw potato. I'm pinching the smash potato idea as they can never manage to crush up spuds! We used to do apple but now do banana as it's easier to smoosh up for testing.....
    Ann Chinnery likes this.
  7. Ham (protein), pasta (starch), cheese (protein and fats), flapjacks (sugars and fats)
  8. We stopped using grated cheese as it is coated in flour & gives positive for starch. Easy enough to buy a block, grate it & freeze it in Gallipots ready for use.
    We also cut our bread up in small bits & leave it out in a tray to dry. Once dried it keeps for months ( or years if the mice don't pinch it :p)
    We use Instant potato too & cous cous.
  9. Do you use the cous cous dried or do you put water on it first?
    I haven't had any complaints about the cheese testing positive for starch....maybe the kids don't bother testing it??...I had better buy myself a grater and a proper block of cheese!!
  10. I powder it all in the blender, just let the cheese dry out.
  11. We use instant mash powder, milk powder, cereals, biscuits, crisps, yeast, flour, butter, sunflower spread, oil and cheese
  12. JFKtech

    JFKtech and then there were two - now JFK Techs :)

    I've had complaints recently that the cheese doesn't test positive for protein, likewise dried egg white. Presumably it works for you guys ?!
  13. Cheese works for us - just takes a little while
  14. If we're using egg powder we make it strong, like a 5% solution and that gives a pretty decent positive, it does make it a little obvious however if the teacher is looking for unknown solutions as it's pretty opaque....
  15. I tend to use apple too as often have one at the back of the fridge that needs using up! But like the idea of banana.
    Have also discovered mini marshmallows are good for both sugar and starch and also use rice for starch.
    Jenny D likes this.
  16. Yes, it does, if it's not ready grated. We use bog standard tesco cheddar.
    We use mini marshmallows too. One for the pot, one for me, one for the pot....:p
    ClaireS and Lisa J like this.
  17. We put hot water on the cous cous. Something else that gets frozen in the Gallipots.
    ClaireS likes this.
  18. We use
    egg white
  19. If you want a top tip for the testing of cheese go for Cottage Cheese, pulverise it and filter to make an extract it will test +ve for protein and reducing sugar. I've seen people trying to get a result with Cheddar Cheese by Adding the Biuret reagent directly to the Cheese with no joy.:D:D:D Also you can get a really strong colouration if you use QUANTITATIVE BIURET REAGENT where the intensity is proportional to the number of amino groups of the protein. You can reduce the mess by using a Dimple tray.:);)

    Food tests.png
  20. Our results are fine:p