Hard copy Journal

Hard copy Journal

Yeah...Since the concept of online journals was new to me, and I wanted to work in school but didn't have a laptop, well most of my initial brainstorming and lists of variables and whatnot are on paper. Very messy paper. So, here (clicking will enlarge the scans):

This is the preliminary brainstorming, when I haven't even settled what to cook. It started with dumplings (which then led to questions about consistency and factors involved), but then Ms Tan suggested fish balls...The format of my results were xy graphs pretty much from the start though, and this was also when the infamous Image-J debuted.

Variables/constants/likely relationships between them hashed out during science block, note the top with hastily scrawled ideas from discussing with others.

The difference between a theoretical experiment (and tables) with square tangyuan (in pencil) dreamt up during class and the actual trial with round tangyuan (in pen) developed after actually trying it. Who knows, there is a reason why generations of Asian women make balls instead of blocks. Also, see how the measurements ended up being halfway across the page because there wasn't enough space.

Cleaned up version of the table, still with random bits of data everywhere they're not supposed to be of course, plus reflections for the trials below.

Number crunching time after trials 1 and 2. The top part is feedback from friends who took a look at my blog so far, bottom is the data for density used while discussing the results with Ms Tan.

Working for the new shape of tangyuan (same surface area, different volume), and finally getting it.

Trial 0 and the actual experiment...

(p.s. If you're wondering why there're strange bulges all over the paper, why yes, I did spill water on it while cooking tangyuan.)

Directors's Cut: Trial 1

Directors's Cut: Trial 1

This...went about as well as could be expected, I guess. Being the first, the no-prior-experience-totally-untested-theory-from-books-only product it was. Basically if you look at the experiment steps you'd be thinking...hey, that emphasis is strange...oh! and this out of the blue apparatus as well, and then you take a look at the results and yup. few balls short of the proverbial ball pit.

Or in other words things went wrong, let me show you why (I think).

• GRB stuck to everything. Every-single-thing-and if-that-thing-didn't-exist-they'll-find-a-way-to-stick-to-it-anyway. No doubt it was dough exhibiting its properties, but still very disruptive to the shape of the balls, so dustings of cornflour are worth possibly decreased consistency of results.
• In a subset of the above, GRB stuck to the strainer used to display and lower them. Unfortunate combination of hot steam and basic properties, will change to bare hands.  

A lot of the dough was left, skewed results severely

• Dots of food colouring in an attempt to reduce the amount of colouring needed rubbed off onto the plate and other GRBs. Returning more traditional method of just mixing colouring into dough.
• Rice dough holds its shape abysmally. Even without multiple weigh-ins and a trip to the displacement can, their shapes flattens between the seconds it took to take a picture for measurements of surface area. Hence: finish as many steps as possible before shaping, and shape more times if necessary. Hopefully the cornflour will help.
•   Water heating at 200°C meant water constantly boiling over. The violent upwards movement of bubbles propelled the GRB upwards as well. Impossible to  discern when they floated naturally with much accuracy, also added (250ml of) water eight times to save the hotplate. So, hotplate at lowest possible setting (120 °C) that's still above boiling point. Future experiments varying amount of heat will just have to have less water, or be incredibly long.

LB: Trial 1 Results

LB: Trial 1 Results

Date: 30 June 2012

Time: 3pm-7pm
Room temperature: 27°C

Weather: Sunny 

**In figure 2, the difference between manual and image-j values for ball-shaped GRB's surface area is because image-j only calculated 2D area, which you can see is not very different from the other types of GRB 

Figure 5: Photos used to derive values for surface area

As you can see from figure 1, the GRB generally shrinks in all aspects after cooking, which contradicts my hypothesis. Figure 3 also shows a lack of internal consistency, with a 20cm² of difference, even before cooking, between two supposedly identical flats. More details (eg speculations on why) can be found in the commentary post. 

LB: Trial 1 Procedure

LB: Trial 1 Procedure 

Research Question: Does the process of gelatinisation cause the GBR to float?
Hypothesis: The higher the surface area to volume ratio, the faster the GBR floats in water.

Steps

   1. Measure out 100g of rice flour and water using a weighing scale, mix until evenly distributed.

Dough after mixing

   2.  Divide the dough into 6 parts, 4 parts of 40g each using the scale and 2 parts of 20g each using a spring balance.

Use cling wrap to prevent the dough from sticking

Keep adding dough, then press the lumps together when the amount is correct

3.  Roll all parts into balls. Then, evenly flatten 2 of the 40g balls until about 1 cm thick, leaving the rest untouched.

4.  Mark 1 GRB from each category (40g flats, 40 balls and 20g balls) with a dot of green dye. 
5. Lay all GRB on black paper covered with plastic, with a ruler in sight, and then take a photo from directly above.

This photo will be used for measuring surface area 

6. Individually wrap the 2 20g balls in cling wrap and place them inside a plastic bag. Squeeze out remaining air before twisting the bag closed.

Due to the cling wrap, the balls will not stick together

7. Fill a displacement can with water, and slowly submerge the plastic bag while using the 100ml measuring cylinder to catch the displaced water. Record the volume and repeat steps 6-7 for the other two pairs.

Place the can on a flat elevated surface, e.g. kitchen sink

    8. Using a 250ml cylinder, pour 750ml of water  into a pot. Put the pot on a hotplate set to 200°C and start the stopwatch. When the water has begun to boil, slowly lower all GRB into the water with a strainer.

The water should take about 3 minutes to boil

Make sure the GRB are not sticking together

      9. Stir continuously with the strainer and record the time it took for each GRB to float. Turn off the hotplate when all GRBs are floating.

The white 20g ball floated first.

    10. Using the strainer, transfer all GRB into a plate while making sure they are not touching each other (prone to sticking) and leave them to cool for 30 minutes.

11. Repeat step 5. 

12. Repeat steps 6-7, but directly slipping the GRBs into the displacement can without wrapping them. 

13. Weigh each GRB with the spring balance again.