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Re: Food Science B
Posted: February 8th, 2017, 5:26 am
by Sasstiel
witwi465 wrote:One of the items on the list of students to bring to the competition is a 9-volt conductivity tester. I have looked it up on Amazon and it costs over $200. I will leave the link below. Is there an alternate item or a low cost one, or did I just view the wrong conductivity tester?
https://www.amazon.com/Extech-Conductiv ... B0137IN21A
My coach says that we don't need one (which we didn't). They were too expensive to buy and too confusing to make.
Re: Food Science B
Posted: February 8th, 2017, 6:08 pm
by Skink
It's an artifact from the Powder event rules. That said, they're in the rules, so competitive teams will bring them. Fortunately, they take minimal effort (or know-how) to home-make; there are instructions either on this or the National site.
Re: Food Science B
Posted: February 8th, 2017, 6:15 pm
by Sasstiel
Skink wrote:It's an artifact from the Powder event rules. That said, they're in the rules, so competitive teams will bring them. Fortunately, they take minimal effort (or know-how) to home-make; there are instructions either on this or the National site.
So far, we haven't used one
I suppose, if you want to take the time to make one, you can, but my team decided not to.
Re: Food Science B
Posted: February 9th, 2017, 5:49 am
by dholdgreve
witwi465 wrote:One of the items on the list of students to bring to the competition is a 9-volt conductivity tester. I have looked it up on Amazon and it costs over $200. I will leave the link below. Is there an alternate item or a low cost one, or did I just view the wrong conductivity tester?
https://www.amazon.com/Extech-Conductiv ... B0137IN21A
There is no need to invest that kind of money. Here is one from Carolina for $28.00 that will do everything needed for this event.:
http://www.carolina.com/catalog/detail. ... AlhN8P8HAQ
We ran this event a few weeks ago and had a station where we asked the kids to put 4 soups in order from least saline to most saline. A device like this would perform admirably.
Re: Food Science B
Posted: February 9th, 2017, 7:28 am
by Sasstiel
dholdgreve wrote:witwi465 wrote:One of the items on the list of students to bring to the competition is a 9-volt conductivity tester. I have looked it up on Amazon and it costs over $200. I will leave the link below. Is there an alternate item or a low cost one, or did I just view the wrong conductivity tester?
https://www.amazon.com/Extech-Conductiv ... B0137IN21A
There is no need to invest that kind of money. Here is one from Carolina for $28.00 that will do everything needed for this event.:
http://www.carolina.com/catalog/detail. ... AlhN8P8HAQ
We ran this event a few weeks ago and had a station where we asked the kids to put 4 soups in order from least saline to most saline. A device like this would perform admirably.
Thank you! I will ask my coach for this
Re: Food Science B
Posted: February 9th, 2017, 10:15 am
by smolblob
Sasstiel wrote:In the last meet I attended, there was no "lab work" with Benedict', Biurets, etc. Any ideas why?
it's really just up to the event coordinator. I think it would be in their best interest to test that and ensure the competitors have a good knowledge of the tests, but it's just an option that they can choose to take.
on a side note, what tests did you guys have to do for the lab part? aside from the obvious ones like benedict's and biuret's, have they given any ~weird~ solutions/chemicals to test with?
Re: Food Science B
Posted: February 9th, 2017, 10:34 am
by goodcheer
Sasstiel wrote:cwscio wrote:Has anyone evaluated the equations found in the 2017 power point on Soinc.org/food science?
I have asked a chemical engineer to assist us with the equations. He looked at the power point and shook his head at the manner in which it was written.
I would suggest not using that; the rules call for joules/gram. However, if you want to find calories, here's the equation I use...
Q=m*c*ΔT. Q is the number of calories, m is the measurement of water (in grams, 1 mL = 1 gram), c is this equation: 1 calorie/gram*degree Celsius, and ΔT is the temperature of the water before burning subtracted by the temperature of the regular water (this is in degrees Celsius) (for example, 40-32=8).
If you want to convert calories to calories/gram, find the mass of the food before burning and divide the calories (what you just got) by that mass. Also, 1 cal/g = 4.1868 Joules/g.
I agree the powerpoint is not very clear with the calculations for calibrating the device and for using it in testing. It is probably clear to those with good understanding of the concepts, but for many of us, like me, we are left scratching our heads.
My questions is this: the letter c in the equation, is that a constant for water?
The powerpoint has it equal to two values: 4.18 J/(g degK) and 1.0 cal/(g degC). Is that correct? Should the degK be degC?
I appreciate those who took the time to put the ppt together to try to help, but my density is very high and my heat of combustion is....not constant.
Re: Food Science B
Posted: February 10th, 2017, 10:23 am
by NeilMehta
Would an n-spire be okay to use for the competition as a calculator?
Re: Food Science B
Posted: February 14th, 2017, 11:00 pm
by Jesusfather123
Can someone suggest a good website to study about vitamins ?
Thanks
Re: Food Science B
Posted: February 17th, 2017, 6:22 am
by smartnerd30
looking help for this problem on how to solve it.
4) For an adult on a 2000 calorie diet, what is the maximum amount (in ml) of this product that he can consume per day based on recommended daily limits listed on the label.
Serving size is 2tbsp (30ml), servings per container 32
vitamin A 2%
Calcium 4%