Take Away Food Testing

[cactus155]

Hi all,

Does anyone have or know of a experiment/experiments to test the amount of fat in a take away burger with others from the same chain and different chains????

We tried today using a blender, adding a small amount of water and then placing the result mush on a piece of filter paper but the teacher was unsure of whether the result was due to the fat or the water

Thanks

[Sassi]

I'm not sure I would ever want to know how much fat is actually in one of those things, yuuuuuuuuuuuk! But how did you actually do it, the filter paper I mean...

[cactus155]

But how did you actually do it, the filter paper I mean...

After it was blended up we placed a small amount of the resulting mush on the filter paper and left it to soak into the filter paper and after a while there was a ring of what could have been fat, water or a combination of the two around the mush. The teacher wants a definate way to determine how much fat is in the burgers

[smiley]

Dunno about fat testing, but we grew mould on bread and got some pretty interesting results. We used fresh bakery bread (Brumbies), supermarket white bread, and a Macca's cheesburger roll. (You wouldn't believe what it took to get a plain roll from them!) Anyway, the bakery bread, with no preservatives, grew mould in a couple of days, supermarket bread a bit longer, and the M roll went for more than 2 weeks, and then only a tiny speck! Scary, huh?

Cheers, K

[Whspa]

I just found this on an internet site.

"If a drop of liquid (such as alcohol, water or oil) falls on paper it makes a mark which is bright and translucent (lets light through) when the paper is held up to the light. With some liquids the mark disappears as soon as the liquid evaporates. Alcohol takes a few seconds to disappear, water takes about a minute, but oil remains, forming a permanent grease spot. In this way paper provides a method of distinguishing between oil and other liquids."

Carol

[Robb]

Hi All,

There is a very affective way of determining fat content. Although it may not be feisable within a school but I will list it anyway incase there is someone whoms knows the process or has the equipment.

The equipment you use is called a soxhlet Extractor. (It looks similar to a condenser but it has external glass piping within the glass inner column). And what it does is allows for a thimble (Test tube looking porous paper, (Thick filter paper really!)) and this thimble is where you add a know mass of food of interest. (Say 50.0000g) And this then get placed in through the top of the Soxhlet Apparatus and rests on the glass shelf approx half way down the column.

Simply then attach a 500mL Quickfit round bottom flask to the based which contains (250mL) of Choroform, (needs to be Chloroform) and then attached to the top of the extractor a condenser to collect vapourous chloroform. The apparatus then is heated (with a heating mantle, due to flammability of Chloroform) and the soxhlet extractor allows the vapour of chloroform to condense in the condenser at which point the liquid then falls through the thimble which then allows the Chloroform to absorb the fat/oil.

This process needs to continue for at least two hours, thhis is to allow for the whole sample to be in contact with the Chloroform. At the end of the process pull the apparatus appart simply evaporate the Chlorofom off using a fume cupboard for obvious reasons and the residue left is the fat/oil content.

Simply re-weigh the sample residue and subtract the original weight from this to give you your fat content. Do some tricks with your results by applying them as apercentage of fat content and go from there.

Beaware though, Soxhlet extractors are extremely expensive and very fradgile as the are external glass piping conected to is that protrude out and up the soxhlet extractor.

Only scientific suppliers will have access to soxhlet extractors. They do range between $200 - $300, each. And the thimbles are roughly $20.00 each (supplied only in packs of 10).

Cheers,

Robb.....

[JudyM]

I was thinking something along the lines of whspa.

Perhaps once the water has evaporated from the filter paper the amount of fat could be measured as a visual thing, using a ruler to measure how far the fat has spread. Maybe even weigh the filter paper before & after.

I'd be interested to find out how you get on.

Cheers
Judy

[Ocker]

Reducing things to basics
1 get say 100g sample of meat
2 Add 100ml of water and mush
3 bring to boil for 2 minutes
4 Strain through fine mesh
5 Put in evaporating dishes & evaporate water off
6 Weigh result oil/fat & You're left with relative ratios of fat per sample

[Rita]

We had a happy meal (including coke) in a blender. Poured this into a measuring cylinder and let stand until the next class. Two layers of fats were found. Fat content could then be measured.
Am trying to attach photo.
Rita