My Awesome Revelation

Long time no post man. LOL.
Anyway, remember how I found out that my experiment is actually used for making curry stuff? Well, my aunty happens to do this experiment practically every week. Why? Because she sells mishti. Mwahahaha. So I asked her about my experiment and I found out that...

Too much vinegar = the end product is too hard and smells really bad but there is also more
Too little vinegar = end product doesn't form too well, smell isn't as bad but not that much is made

Also, when I told her how much milk I used, she told me that you could get less than a hand full of casein. Well, now I know how much I lost down the drain. And why she has humongous pots in her house.
Furthermore, I delved into the deepest pits of my memory until I remembered my parents making mishti, and I really wanted to help. Anyway, the main point is that when they filtered the casein, they used a cloth to drain out all of the water, so that the water could completely come out and no casein would be lost. Now I know why a normal strainer didn't work. x.x

So... all that's left is for me to do my experiment again? Oh wait, I have to write up my method, AGAIN. Waaaaaah~

----- I just realised, do I list my aunty in my a references, bibliography or acknowledgments? I'm leaning towards acknowledgment...

Something which I should have mentioned....

Ok well, you know how I was doing the experiment before? My parents happened to see me (well, more specifically my dad) and he asked me why I was making some of this curry dessert thing called mishti. And I was giving him the O-o face and then I realised that it was true. Then he started laughing at me.

Anyway, I'm pretty sure if you're not of Bengali/Indian/etc background you'll have no idea what it is, so I tried researching it.
Well, in Bengali, "mishti" literally means "sweet" in English. You can have a large variation in the way they are made so you can get different shapes, colours and tastes.
For example, the ones below are white and black(yes I know they're not black but we just call them that) mishtis.

I don't know what it looks like to non-Bengali people, but omg, this looks so yummy. X.X
I searched up some recipes for it on the internet and instead of using vinegar, they use lemon juice. Which also has acidic properties so naturally casein would form. (http://indianfood.about.com/od/sweetsanddesserts/r/chamcham.htm)

So, I thought that this is one of the things that I could put in my introduction. I could say that my research could help maximise the quality of the mishti? Or something like that. 8D

--------- I just realised when I use the term "curry" I mean people like Bengalis/Indians/Pakistanis. I'm not sure if this is racist, but I use it all the time and I know heaps of other people who use it too... Anyway, just know that I'm not reffering tothe curry that you eat with rice. Yeah, that spicy thing. Totally does not go with dessert. LOL.

Why does the Milk Curdle when I add Vinegar?

Well, I knew that I had to answer this question, but seriously, the chemical bonds and everything look so complicated. Seriously, I went on this site: http://www.itisacqui.it/sitob/formagette/curdling.htm to find out what happens, but it's so hard to understand. ;-;
Anyway, I might ask Ms Zhang for help on it ^^''
Until then, I have a diagram. Of casein.

I'm not gonna lie, I have NO IDEA as to what the labels on the picture are.
All will reveal itself in the due course of time... 

Anyway, I went on yahoo answers and google to try and find out the answer to the question that is on the title of this post.
I'm not even sure if we're allowed to use yahoo answers. LOL.
Ah well, I'll just trust the people with a professional looking profile picture. AHAHAH.


One person said "The hydrogen ions from vinegar (5% water solution of acetic acid) react with -NH2 groups of lysine and asparagine to clot the milk and drive proteins out of solultion."
Um, yeah, so what is lysine, asparagine (related to asparagus?) and MINUS NH2? I understand the NH2 part but why the minus?!! There was also a typo in 'solultion'. Now I know why teachers don't like yahoo answers.

On to the next website. A cooking website. Don't you just love my variation in sources. Not. I should be using books or something shouldn't I? Too bad, it's the 21st century
According to Shirley Corriher on  http://www.finecooking.com/why-vinegar-curdles-milk.aspx "Acid on protein causes the protein to coagulate, because the acid is actually "cooking" the protein strands. When vinegar curdles milk, what you get is a dairy version of scrambled eggs." and that "When in doubt, a little cornstarch is always good insurance to prevent curdling."
Well, at least I can understand this answer... No, I still don't know what "coagulate" is. Why isn't this taught in school? -cries- Anyway, next time I am going to do the following because I'm really tired right now and need a shower:

• Find out why milk curdles when I add vinegar? (what I should have answered here)
• Learn what coagulate is
• Ask Ms Zhang for help
• Try and find more stuff on what happens when I add more vinegar to my milk (there are seriously NO websites with this!!!)

Different Types of Milk

So, for my experiment, obviously I'm going to do more than one experiment, because otherwise it would be too easy and I wouldn't be able to make very many conclusions. I think I said that first I'll do experiments where the independent variable is how much vinegar is added to the milk. My second "lot" of experiments is going to be with a fixed about of vinegar but with different types of milk. So this is research on the the second experiement.

It's said that whole milk is recommended for children, teenagers and body builders, and people trying to lose weight should drink skim milk which is actually funny . This is because, according to differencebetween.net (http://www.differencebetween.net/object/difference-between-skimmed-milk-and-whole-milk/) whole milk has all of the fat from the original cow milk, and usually, there is 3.5% of milk fat** for every cup of milk. However, in skim milk, there is a skimming process where as much fat as possible is taken out. This leaves the skim milk with 0.5% of milk fat, because obviously, not all of the milk fat is taken out.

The fat from skim milk is taken out by centrifuges. (http://www.answerfitness.com/tag/whole-milk-versus-skim-milk/) (hmm. this term seems so familiar. oh yes, year 8 FTW) Based on personal knowledge, centrifuges spin a liquid around and the excess solid is taken away. I'm pretty sure this is also how blood is put into a centrifuge and thats how you can see the plasma, red bloods cells and white blood cells.

 The fact that whole milk has more fat in it than skim milk means it's tastier. Obviously. I hate skim milk. It already smells, so curdling it will make it even worse.

I should really start my experiment.

**is the fatty portion of milk. wikied the definition....^^ (http://en.wikipedia.org/wiki/Butterfat)

SRP update...

I feel so bad, I haven't updated this in so long. I had to read over my posts to see what I had done in relation to my experiment... and realised why I got such a bad mark D: Anyway, I'll try harder from now on.

Ok, so I did a little more research and I found out some really interesting stuff. I might repeat some stuff but it's worth repeating.

Well, from the mixing of the vinegar and milk, you get casin as I've said before, and it occurs when the protein in the milk meets the acid in the vinegar. True plastics, called polymers, are a different in the way that they can be solids or liquids, and the molecules can chain themselves together, which is why you can get stuff like slime.
I got this information from:
http://www.sciencebob.com/experiments/polymer.php

On this website (http://pbskids.org/zoom/activities/sci/plasticmilk.html) it says that the chemical reaction separated the milk into two parts, the curds which is the solid and the liquid which is the whey. Also, on this website, kids as young as 6 did this experiment, which made me feel really bad. But they said that it felt like "wet playdough" and "smelt really bad". Something in my research with variables finally came up and a person said "
The skim milk smelt the worst, the 1% was the best we thought, 2% and whole milk produced the most, but was the bumpiest. " I have no idea what they're going on about with the percentages but I can conclude that whole milk might create more casein. I am seriously wondering why. Another thing to research.

Another thing I found out was that Little Miss Muffet was really eating this, in her nursery rhyme. This is because curds and whey as mentioned above can be made from milk by the help of a coagulant (something that helps cause a transformation of a liquid for example into or as if into a soft, semisolid, or solid mass). I saw the pictures of it and it looks seriously gross...

Um yeah. I'm SO glad I live in the 21st century, because people actually had to eat that stuff back in the day when their milk spoilt. O_O''
Casein was also manufactured into buttons, crochet hooks and knitting needles between the World War 1 & 2.  After World War II advances in technology made casein plastics obsolete.

More Research!

I looked arouns various sites, and of course they all have different procedures. For example the one on WikiHow (http://www.wikihow.com/Make-%22Plastic%22-out-of-Milk) says that I should microwave the milk. But most other methods like this one (http://www.instructables.com/id/Homemade-Plastic/) say that I should boil the milk to a certain point. I'm pretty sure boiling the milk would be more accurate, as the microwave could have some small errors. Also, it doesn't really seem scientific to use a microwave...

Casein is actually used in cheeses to keep it together and in glue! It's also used for numerous other things, such as paints, soap making and cement, as shown by this website: http://chestofbooks.com/home-improvement/repairs/painting/Paint-Making-Color-Grinding/Part-V-Casein-And-Cold-Water-Paints-Chapter-XXXI-Origin-A.html.

Some properties of casein are that it is tough, flammable, resistant to water and has poor dimensional stability (I'm not exactly sure what this means, but I think it's the ability of something to stay in its original dimensions when it's being changed. I will ask Ms Zhang when I see her next!) with info taken from http://books.google.com.au/books?id=0g9QjxsbqmUC&pg=PA136&lpg=PA136&dq=casien+plastic+heat+chemical&source=web&ots=u7KLwl6eWg&sig=9V40234r-SgMztftGpwzPYDrQgI&hl=en&sa=X&oi=book_result&resnum=1&ct=result#v=onepage&q=&f=false

One last thing. Ms Zhang mentioned that I have to put in water with the milk and everything for my experiment but it's not in any of the methods I've encountered! Maybe she accidentally said the wrong thing. :D

Researching the Experiment

I have to know what the method (equipment and procedure) of the experiment is, so I need a type of guide that tells me what the basic method for my experiment is. Of course, I'll be changing this when I actually do my own method in passive past tense and all that jazz.
Seeing as I don't know how to do references or proper bibliography yet I learnt it in year 8 though.. oops , I'll just make a link to the website. =D

http://www.csiro.au/resources/plastic-milk-activity.html

From another website, people actually explain why the milk turned into 'casein.' Apparently they use this stuff in cheese. Kind of gross but hey, it's awesome science. -cough cough-

http://www.newton.dep.anl.gov/askasci/chem00/chem00367.htm