Taste Tests and PTU

[rae]

Hi All,

One of our teachers has just asked for Phenylthiourea(PTU) to do taste tests. Apparently some people can taste it and others can't.
Does anyone know a substitute for this that would have the same effect?
PTU costs $182/25g ,he's got to be kidding!!

Thanks
Lorrae

[smiley]

We have PTU papers in my store cupboard. They were purchase in the PKE (the pre-Kristin Era) but I'm guessing they came from somewhere like Southern Biological, judging from the packaging. Check suppliers, I'm sure that will be a cheaper option.

Cheers, K

[rosalie]

Southern Biological have PTC Paper strips for taste tests. 100 for about $12.

Rosalie

[Ocean Breeze]

What does PTU taste like? When and where would you use it?

[smiley]

Hi again. Yes, its PTC papers. I just went onto the Southern Bilogical website 5 mins ago, and they say they no longer stock it, but Science supply does, and it's approx $9.00 (8-someting actually) for 100 papers.

Cheers, K

[rae]

What does PTU taste like? When and where would you use it?

I think it has a bitter taste and is used in genetic testing. Apparently you inherit the ability to taste the bitterness or PTU or not. It is linked with the ability to taste the bitterness of certain foods. It is also used to treat certain typers of thyroid disease.

Lorrae

[smiley]

We had an hilarious time yesterday getting various teachers to try the taste paper in the staff room, under the guise of "I think this might be too old to work now". One teacher put it on the tip of her tongue, and said "Nope, no taste at all". We told her to try the back of her tongue, whereupon she ran screaming to the kitchen for water. Consensus among the "tasters" was that jelly beans helped eliminate the (apparently) foul taste.

If you do the reading, the Americans (typically) use it to formulate race-based statistics. The rest of the world just views it as an interesting genetic trait. I can't taste it myself. I must be in the 30% that can't. Mind you, our stats were lower than a 70/30 split. Apparently the break up is 20% of people are homozygous tasters, 50% are heterozygous tasters, and 30% are non-tasters. Are we Homozygous non-tasters? I would guess so.

The truly scary part in my reading was the line "tasters are only able to taste this product if it dissolves in their own saliva, and the solution was not prepared using another person's saliva.YUCK!! Imagine being asked to make that up! Let alone try someone else's solution.

Good Luck with using it. It rates as a good laugh. Cheers, K

[RosalieM]

If it is what I am thinking of, we used this paper when I was at uni in genetics. It is in brussell sprouts so those people who like brussel sprouts can't taste the PTU and those who don't like brussel sprouts can taste it. I used it after that as an excuse not to eat them when I went home on holidays "I can't eat brussel sprouts Dad - it's genetic!"
Rosalie

[labman]

Hi All,
I buy mine from Omega Scientific (S.A.company) for $6.00 per vial of 100. They also sell control papers for the same price, some teachers like to have those on hand too. They have no taste to react to, but the students don't know that!
Contact number for Omega is (08)82894311
Cheers,
Lisa

[J]

I love brussels sprouts!!
I guess that means I'm a non-taster.
Wow! The things you learn on this site!


Julie

[dolphinscales]

If it is what I am thinking of, we used this paper when I was at uni in genetics. It is in brussell sprouts so those people who like brussel sprouts can't taste the PTU and those who don't like brussel sprouts can taste it. I used it after that as an excuse not to eat them when I went home on holidays "I can't eat brussel sprouts Dad - it's genetic!"
Rosalie

I dont think this is correct - i am a taster and i LOVE brussel sprouts!!!


I thought that this tasting prac was restricted or banned due to the fact most people who cannot taste keep going back in case they got a "bad" paper - and the stuff is not good for you . I know in WA we are not allowed to do it any more.

Mind you it is a pitty as i think it is a great prac - sigh!

[Ocean Breeze]

Gosh! The info we can learn on this site! Brilliant!
So am I hearing that its a prac that can be used to demonstrate genetics in sr Bio, rather than eg, the juniors yr 8 Bio topic that involves taste testing?

[smiley]

Don't know about Seniors v Juniors prac, but have you done the prac where kids map their families with the 8 non-race-based human traits?
The traits are: Widows peak present or absent
Earlobes attached or detached
Ability to roll the tongue
Cleft chin present or absent
Hair on 2nd metacarpal (ie middle section of finger) present or absent
Profile of fingernails curved or flat
Which thumb on top when hands are folded(for most of the world its Left)
2nd toe longer or shorter than big toe.

All these traits are represented across the spectrum of humankind, and are not race-based like eye colour, hair colour can be.

We did this prac up here,and got the kids to assess as many of their family members as possible. Interestingly, we had some boarding kids from a remote community and 7 out of 8 had identical traits, demonstrating how things run in families. The hand-folding one is definitely the freakiest. Try it.

Cheers, K