Australia's Science Forum

We just introduced this subject and one prac teacher wants to do is determination of water in fruit, veg and meat. She is planning to dry it over few days in lab . No good. I do not want fresh meat laying around in heat for days.
What is the easiest way of doing this prac?
I was going to ground small amount of beef with a known amount of sand and dry overnight at 105oC. Same with fruit and veg. Would this work?
Lada

We have done this in the past with junior year groups. We would use ham and other fruit, vege, fats etc and dry them in the oven for a few days. You only need it at a lowish temperature say 60deg. The ham doesn't smell as it dries out quite quickly.

How does this fit in with senior science??

Thanks, Rae
I will ask teacher if processed pork (ham) still classify as meat.
But it could work with fresh meat too, if temp only 60o, it will not cook it

Hi Lada,

We incubate it for a few days but we use ham or other processed meat. I do not think rotting fresh meat is OH&S friendly for several reasons.

Thanks Rae and Lou,
sounds like ham it is!!

Any meat is OK! as long as you keep above 80 C in drying oven!
Some of the fruits though present a problem as they remain soft and never dry completly
I just had a thought! Has anyone tried this experiment in a solar dessicator?

We did something similar last year using a dehydrator that we borrowed from our Home Economics people.

Yep...dehydrator from home science works best. I will never allow meat to be dried in the incubator oven again. Took years to get the smell out. Also with the dehydrator and fan the moisture from the food evaporates better than in the oven.

We place them in labelled paper bags and dry in oven over a few days and the students measure the weight before and after drying without taking items out of paper bag. then we dispose of the bags with contents inside.

Hope that may be of some use.

Superbug

We use a food dehydrator. It has trays to allow the air to circulate and dry the fruit etc. Works well
Adrianna

our SS teacher burns the crap out of it..weighing it before and after - and thats the water content. He requests ham & tomato.
I hate it - it stinks out the place.
The other teachers don't think it is effective - but he wont listen...so burning it is!!!