What types of food spoil the fastest?

[Schrodinger's Dog]

It's about two weeks before my course starts, and I'm looking to find a new experiment; if anyone still remembers the chocolate milk and milk experiments with sugar in, they were a lot of fun for me and I hope people enjoyed them as much as I did.

https://www.physicsforums.com/showthread.php?t=111458&highlight=milk

So can anyone suggest something that's not obvious, but an experiment to test it that would be fairly easy to set up.

At the moment I have a few ideas: for example: what food type goes off first, using high protein, fat and sugar and carbohydrate and fibre foods to see which stay fresh the longest.

or maybe an experiment involving my dog, I'm kind of stuck on what to do.

If anyones interested in a little light hearted experimentation - under scientific conditions of course - well as close to science as I can get - please suggest any ideas.

 

[Moonbear]

I'm afraid to suggest anything. Last time, your cat died during the experiment.

 

[Cyrus]

You should put mentos into diet coke.

 

[Schrodinger's Dog]

I'm afraid to suggest anything. Last time, your cat died during the experiment.

Don't remind me, but that wasn't due to the experiment.

You should put mentos into diet coke.

I think that's covered pretty much by Mythbusters.

Thanks anyway. All suggestions welcome.

 

[berkeman]

It's about two weeks before my course starts, and I'm looking to find a new experiment; if anyone still remembers the chocolate milk and milk experiments with sugar in, they were a lot of fun for me and I hope people enjoyed them as much as I did.

https://www.physicsforums.com/showthread.php?t=111458&highlight=milk

So can anyone suggest something that's not obvious, but an experiment to test it that would be fairly easy to set up.

At the moment I have a few ideas: for example: what food type goes off first, using high protein, fat and sugar and carbohydrate and fibre foods to see which stay fresh the longest.

or maybe an experiment involving my dog, I'm kind of stuck on what to do.

If anyones interested in a little light hearted experimentation - under scientific conditions of course - well as close to science as I can get - please suggest any ideas.

Sorry, I wasn't part of the old thread (and it's too long for me to make sense of quickly), so I'm not clued in. What is the class, and what are the rules for picking a project? I'd love to suggest something, but I'm not sure of the guidelines.

 

[Moonbear]

Don't remind me, but that wasn't due to the experiment.

Are you sure? That was a lot of sour milk to drink.

Sorry, I wasn't part of the old thread (and it's too long for me to make sense of quickly), so I'm not clued in. What is the class, and what are the rules for picking a project? I'd love to suggest something, but I'm not sure of the guidelines.

It's not for a class. It's something to keep him occupied while not in classes. Last time he did a comparison between regular milk and chocolate milk (and then I think he did a modification of that with various amounts of sugar added to the milk) to determine which turned sour first after sitting out at room temperature. It was mostly being silly, but in the end, a fun exercise that I thought would be good to use with elementary students to teach about things like experimental controls...and uncontrolled variables, like the cat having a preference for one of the bowls of milk.

 

[Schrodinger's Dog]

Sorry, I wasn't part of the old thread (and it's too long for me to make sense of quickly), so I'm not clued in. What is the class, and what are the rules for picking a project? I'd love to suggest something, but I'm not sure of the guidelines.

As Moonbear said it's just for fun so any suggestions are welcome.

Are you sure? That was a lot of sour milk to drink.

Aye it was, but let's not dwell on the past.

It's not for a class. It's something to keep him occupied while not in classes. Last time he did a comparison between regular milk and chocolate milk (and then I think he did a modification of that with various amounts of sugar added to the milk) to determine which turned sour first after sitting out at room temperature. It was mostly being silly, but in the end, a fun exercise that I thought would be good to use with elementary students to teach about things like experimental controls...and uncontrolled variables, like the cat having a preference for one of the bowls of milk.

I'm surprised anyone still remembers.

 

[berkeman]

As Moonbear said it's just for fun so any suggestions are welcome.

Fair enough, sounds like fun. What areas of science can it be in? Sounds like the last one was mostly biology and chemistry. What other sciences are fun for you to play in? You could build a 5MW laser for fun like in the movie "Real Genius"

 

[Schrodinger's Dog]

Fair enough, sounds like fun. What areas of science can it be in? Sounds like the last one was mostly biology and chemistry. What other sciences are fun for you to play in? You could build a 5MW laser for fun like in the movie "Real Genius"

Or I could do a Dr. Michio Kaku and build a particle accelerator in my basement. But I have two weeks, so keep it simple.

5 jigawatt at most

 

[turbo]

Remember the "hot water freezes faster" thing? You could take a water sample, heat it on the kitchen stove, removing samples every 10 degrees or so, and place them in marked containers in your 'fridge. When they have all come down to 'fridge temp, put them in the freezer and keep track of when they freeze. It might be better to have a chest freezer for this part of the experiment to keep temperatures consistent.

 

[DaveC426913]

If anyones interested in a little light hearted experimentation - under scientific conditions of course - well as close to science as I can get - please suggest any ideas.

I'd really like experimental confirmation of the complete falsity of the direction of water down the toilet myth.

While it's all well and fine to refute it with logic, it would be nice to actually be able to answer the question "How would you know? Has anyone actually done it?"

 

[Schrodinger's Dog]

Remember the "hot water freezes faster" thing? You could take a water sample, heat it on the kitchen stove, removing samples every 10 degrees or so, and place them in marked containers in your 'fridge. When they have all come down to 'fridge temp, put them in the freezer and keep track of when they freeze. It might be better to have a chest freezer for this part of the experiment to keep temperatures consistent.

I'd really like experimental confirmation of the complete falsity of the direction of water down the toilet myth.

While it's all well and fine to refute it with logic, it would be nice to actually be able to answer the question "How would you know? Has anyone actually done it?"

Both good ideas, I'm kind of interrested in the ice one myself, and it's much easier to set up. Anyway I won't start it 'til this weekend, and I have a week off work next week.

Keep 'em coming.

 

[Schrodinger's Dog]

OK assuming there are no other ideas I'm going to go with the Ice water and warm water thing. I have a freezer so this should be quite simple to set up. Thanks for the input.

 

[DaveC426913]

I guess I'm not enthused about the ice cube experiment is because it has been demonstrated with http://en.wikipedia.org/wiki/Mpemba_effect" .

 

[Schrodinger's Dog]

I guess I'm not enthused about the ice cube experiment is because it has been demonstrated with http://en.wikipedia.org/wiki/Mpemba_effect" .

OK so it's a given. Back to square one.

The orginal milk experiment revolved around a disagreement: is sugar the cause of chocolate milks preservation and not something else, answer: no: that's precisely why it doesn't go off as quickly as normal milk. So what I've got to think of is an experiment that challenges a notion; doesn't have to particularlly grand or involve any laws of thermodynamics, it just has to be something so simple that no one has ever thought about why? I have a whole week or so, so if you can think of anything? Let me know, I'd like to start the experiment on Sunday, but if it's quickly proven, it can run from x till the Sunday after that; that's when I'm back to work.

 

[DaveC426913]

Well, the toilet/sink draining thing would require involvement from others' sinks, including those from the southern hemisphere, so that's maybe not so easy...

 

[Schrodinger's Dog]

I once did a thought experiment about why people think that busses always etither take ages or turn up in threes, but I think that'd be dull .

But it could be anything really, blue tacks an interesting material, maybe something to do with that, like glass it's a sort of "viscous" solid?

 

[turbo]

I guess I'm not enthused about the ice cube experiment is because it has been demonstrated with http://en.wikipedia.org/wiki/Mpemba_effect" .

I actually proposed a slightly different experiment, though, which involves bringing all the water samples to the same temperature (say, in a refrigerator) before putting them in the freezer. This experiment would demonstrate whether water will freeze faster or slower based on its previous temperature history. One possible factor my be that heat can drive off dissolved gases in the water.

 

[Schrodinger's Dog]

I actually proposed a slightly different experiment, though, which involves bringing all the water samples to the same temperature (say, in a refrigerator) before putting them in the freezer. This experiment would demonstrate whether water will freeze faster or slower based on its previous temperature history. One possible factor my be that heat can drive off dissolved gases in the water.

Well reinstated then, you're the front runner so far as the other experiment may be a little awkward.

So for example with have five samples all of the same water source, all heated to different temperatures, and then each is cooled to say 5 degrees in the fridge before being placed in the freezer. I have some ice cube holders, it will be simple to visually inspect each cube to denote when the water has all frozen without desturbing the ice too much, and the level of the freezer is consistently the same temperature, as I have different enclosed levels.

 

[turbo]

Yes, that's the thought. Start out with a big pot of cool tap water, and take a sample out of that, then start heating the water, taking samples periodically as it heats up. I would suggest one more wrinkle - once the water gets to boiling temperature, take a sample, and then let the water boil for 10 minutes and take another sample and perhaps wait another 10 minutes and get a final sample. If de-gasification of the water effects the rapidity with which it freezes, we should expect that there might be a time-related factor as well as temperature-related.

 

[Schrodinger's Dog]

Yes, that's the thought. Start out with a big pot of cool tap water, and take a sample out of that, then start heating the water, taking samples periodically as it heats up. I would suggest one more wrinkle - once the water gets to boiling temperature, take a sample, and then let the water boil for 10 minutes and take another sample and perhaps wait another 10 minutes and get a final sample. If de-gasification of the water effects the rapidity with which it freezes, we should expect that there might be a time-related factor as well as temperature-related.

Thanks that's a real help, I'll start the experiment on Sunday or Monday, and run it as long as necessary. I have a thermometer so I can determine the exact temperature of the water. this should be fairly easy to run and to get results.

Use controls as well of course. Double up on all the water samples.

 

[turbo]

Thanks that's a real help, I'll start the experiment on Sunday or Monday, and run it as long as necessary. I have a thermometer so I can determine the exact temperature of the water. this should be fairly easy to run and to get results.

Use controls as well of course. Double up on all the water samples.

Be sure to keep us updated!

 

[Moonbear]

Since it's also possible that evaporation plays a role, a control you could include is to let some boiled water cool to refrigerator temperature and then measure out a volume into an ice cube tray, vs taking a sample while it is still boiling to cool in the tray. This would better determine if it is the degassing or just the volume loss of a steaming sample put into an ice cube tray.

Don't forget to randomize the location of your samples in the tray. Don't want to always put the hottest sample to the back or front, etc., just in case there's a slight difference in freezer temperature nearer or farther from the door.

 

[Schrodinger's Dog]

Since it's also possible that evaporation plays a role, a control you could include is to let some boiled water cool to refrigerator temperature and then measure out a volume into an ice cube tray, vs taking a sample while it is still boiling to cool in the tray. This would better determine if it is the degassing or just the volume loss of a steaming sample put into an ice cube tray.

Don't forget to randomize the location of your samples in the tray. Don't want to always put the hottest sample to the back or front, etc., just in case there's a slight difference in freezer temperature nearer or farther from the door.

Yeah good tips, I'll start the experiment tomorrow (Monday afternoon) the freezer I think is uniform from front to back because it has 6 draws/compartments, but I will be using controls as a matter of course anyway, need to buy some supplies over the pound shop, science is a costly business.

 

[Schrodinger's Dog]

OK just an update, I've decided due to a technicality, which was I've been sitting watching you tube all day mostly and dallying around here; the experiment will be started tomorrow, fingers crossed unless I start playing that stupid bloody maths game again or watching A Bit of Fry and Laurie and Jeeves and Wooster on you tube.:rofl: so funny those guys, you give him back when you've finished with him, he's a comic legend over here. anyway I digress, in case anyones still even remotely interested it's t minus 18 hours or so and counting

 

[hypatia]

Well? We're all waiting on pins and needles!

 

[turbo]

Welllllllll?

 

[K.J.Healey]

I always wondered if the hot water freezing faster than cold had anything to do with people using hot water from their faucet rather than heating it themselves. Is it possible that hot water heaters can slightly contaminate the water with excess minerals (due to it sitting for hours there just letting stuff fall out and gather). And perhaps these minerals in some way increase the freezing point of the water?

 

[Schrodinger's Dog]

Welllllllll?

Problem, I only have two ice trays so I couldn't start the experiment, I have to go into town to get some, so there's going to be a delay on the start sorry I'd hoped the shop across the road had some as that's were we got them originally but since they've changed management they don't stock them anymore. I'll be going into town this afternoon, so it'll start this evening.

I always wondered if the hot water freezing faster than cold had anything to do with people using hot water from their faucet rather than heating it themselves. Is it possible that hot water heaters can slightly contaminate the water with excess minerals (due to it sitting for hours there just letting stuff fall out and gather). And perhaps these minerals in some way increase the freezing point of the water?

I could heat them in a pan, that should minimise contamination.

 

[Schrodinger's Dog]

Well no luck going into town, It's obviously the wrong season for ice trays, fear not though I've decided to use something else, I'll begin the experiment tomorrow as I want to start a bit of coursework for a few hours, but no worries by tomorrow evening say 6pm EST we should have a yay or nay. I promise

 

[Schrodinger's Dog]

The experiment

Hypothesis: Does warm water freeze faster than cold water?

There is a well known effect whereby hot water will freeze faster than cool water, my intent is to show whether under scientific conditions we can observe this effect.

Method

I have taken 5 different specimins of water and five controls of the same temperature for each dish of water, the dishes are all the same size and all filled to the same level.

The small dishes are all on the same level of the freezer and all pretty much in a simillar position so the temperature should be simillar.

I have boiled some water and then left it pouring out the water, leaving it for fifteen minutes then bringing another source to the boil and letting it cool for the fifteen pouring and the same for the third except without leaving it to cool.

Temperatures are about 100, 80, 55 degrees c respectively the other samples are at room temperature, and near freezing.

I will monitor the water every 15 minutes, and then report every half hour.

Equipment

10 dishes
3 pots for water
a thermometer
a gas stove
some water
a dog
a cup of tea

Ok we have a go on the experiment, I left the chilled water in the freezer for a while so it's pretty close to 0 although no freezing yet. Hopefully this will suffice. Results posted as and when.

Wish me luck

 

[Schrodinger's Dog]

After even just 15 minutes the iced water is freezing, the room temperature water has an ice crust on top, the others are unfrozen so far.

 

[Schrodinger's Dog]

Ok half an hour after the fifteen minute update, oddly the cool water appears from the look of it to be freezing faster than the hot but the 80 degree water is cooling the slowest of all and still has no ice cover on it, the ice water is practically frozen, with a liquid centre.

 

[Schrodinger's Dog]

Ok pretty dull now, the chilled water has pretty much frozen to ice cubes or I should say ice dishes or discs I suppose anyone know what they're called? The room temperature water appears on the surface to be freezing faster but I don't want to risk removing the water until I'm sure it's all frozen around the water so for now I don't know. The 80 degree water still appears the slowest, the 100 degree water appears to be freezing faster than both the 50 degree and the 80 degree but it's difficult to tell atm.

The dog has flaked out on the bed btw, in case anyones interested.

 

[Schrodinger's Dog]

Looks like this going to be fairly clear cut, the room temperature water is almost frozen, the 50 degree is now freezing about as fast as 80 degree with the 100 degree being more frozen at the moment but here really isn't much in it.

Dog has roused himself to sigh occasionally, otherwise he appears disinterested. Probably not aware of the ramifications of science. Maybe he's a creationist?

He has just burst in my room and picked up the rubber chicken, I think it's because he's found a victim to throw it for him.