12.04.2024

BASIS REZEPT/EXPERIMENT 1

30g rice starch


7.5g glycerol

100ml distilled water


15ml vinegar

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PREPARATION:

1. measure the distilled water, glycerol & vinegar, pour into a pot and stirr

2. slowly add the rice starch -> stirr continuously for two minutes with a whisk at 60 degrees Celsius

3. pour into two petri dishes

4. distribute evenly with a spoon

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OBSERVATIONS:
 

thickens quickly when heated, state when poured into the petri dish - creamy thick & white color

after 5 min: same state


after 20 min: completely cooled, surface matt, upper layer pudding-like (spread test) lid (on a petri dish) -> immediately removed (condensation -> not yet fully cooled)

after 36 min: lid on the petri dish

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EXPECTATIONS: 

elastic, pliable, solid material.

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One dish with lid/cover and one without

EXPERIMENT 2

15g rice starch


15g banana powder


7.5g glycerol


100ml distilled water


15ml vinegar

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PREPARATIONS:

1. measure the distilled water, glycerol & vinegar, pour into a pot and stir

2. slowly add the rice starch and banana powder -> stir continuously for two minutes with a whisk at 60 degrees Celsius

3. after 8 minutes of whisking -> too liquid state = due to the banana powder, add another 15g rice starch

4. whisk for 4 minutes

5. remove pot from the stove

6. whisk for 3 minutes without heat

7. pour into two petri dishes

8. distribute evenly with a spoon

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OBSERVATIONS:

Starch did not clump (just as in Exp. 1)


banana powder initially formed many small mini lumps -> dissolved by whisking

state when decanting - creamy liquid, grey beige, initially air bubbles

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EXPECTATIONS:

a more elastic substance (than in Exp. 1) -> banana powder acts as a gelling agent, mould (banana)

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One dish with lid/cover and one without.

19.04.2024

CATCH UP

(12.04.) Experiment 1:
 (picture 1)

with lid - state unchanged: still liquid/creamy consistency, white colour

without lid - state: rock hard at the top (hard plastic) & slightly rubbery at the bottom (not yet completely dried), milky transparent, broken structure/individual chunks, strong reduction of mass

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(12.04.) Experiment 2: (picture2)

with lid - state unchanged


without lid - state: beige brown colour (slightly lighter), firm - yields only slightly when pressure is applied with a finger & pressure marks appear when hard pressure is applied with a fingernail, elastic - can be bent but tears quickly, smooth surface, leather-like to the touch, white dots = air bubbles, mass only slightly reduced The target state of the final material based on this: Elastic, pliable, without tearing

PLAN

Experiment 3 - xanthan instead of banana powder


Mini - Experiments 1 & 2 - exposure of fragments from Exp. 1 & 2 to test water resistance/absorbability

MINI - EXPERIMENT 1

petri dish with distilled water


chunks from the first experiment (12.04.)


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OBSERVATIONS:

After 5min - becomes soft

After 15 (17)min - small particles (white) soak off

After 30min - more pieces soak off

After 60min - upper hard part unchanged, rubbery part (bottom) very soft

MINI - EXPERIMENT 2

petri dish with distilled water


chunks of the second experiment (12.04.)

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PREPARATIONS:

After 5min - becomes soft, sticks slightly to the bottom

After 15 (17)min - upper layer brown, lower layers become beige/lighter in colour

After 30min - much lighter/somewhat lighter than at 15min, top layer still firmest = takes longer to absorb water since the layer was completely dry

After 60min - all soft, water is milky

EXPERIMENT 3

15g rice starch


15g xanthan


7.5g glycerol


100ml distilled water


15ml vinegar

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PREPARATIONS:

1. measure the distilled water, glycerol & vinegar, pour into a pot and stir together

2. slowly add rice starch & xanthan -> stir continuously with a whisk at 60 degrees Celsius

3. whisk for 1 min: Yeast dough-like consistency

4. pour 1/4 into a petri dish and large silver collecting dish

5. distribute evenly with a spoon

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EXPECTATIONS:

more pliable material than in Exp. 1 & 2, white, slight shine

EXPERIMENT 3 vol.2

3/4 of the mixture of Exp. 3

PREPARATIONS:

  4. add 85ml of distilled water

  5. boiled at 60 degrees Celcius

  6. pour into large petri dish and large silver collection dish

  7. distribute evenly with a spoon

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OBSERVATIONS:

sticky consistency, porridge-like, ivory-coloured,

runnier than Exp. 3, firmer consistency than Exp. 2

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EXPECTATIONS:

more pliable material than Exp. 3

EXPERIMENT 4

15g rice starch

5g xanthan

10g banana powder

7.5g glycerol


100ml distilled water


15ml vinegar

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PREPARATIONS:

1. measure the distilled water, glycerol & vinegar, pour into a pot and stir together

2. slowly add the rice starch, xanthan & banana powder -> stir continuously with a whisk at 60 degrees Celsius

3. add another 5ml of distilled water, 5ml of glycerol & 5ml of vinegar

4. whisk for 2 minutes

5. pour into a petri and collection dish

6. evenly distribute the mixture with a spoon

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OBSERVATIONS

lumpy & solid -> just as in Exp. 3, softer consistency/runnier, creamy with very small lumps

26.04.2024

CATCH UP

(12.04.) Experiment 1: (picture 1, left)

with lid - state: slightly firmer, like solid body cream, has a crack -> probably due to slowed drying out

without lid - state: same colour & mass, completely hard, no more soft spots

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(12.04.) Experiment 2: (picture 1, right)

with lid - state unchanged


without lid - completely solid, can be bent -> breaks through



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(19.04.) Mini - Experiment 1: (picture 2)

State - somewhat dissolved = piece is still intact, water has dried out

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(19.04.) Mini experiment 2: (picture 3)

State - solid consistency, dissolved part sticks to the petri dish and is slimy/creamy


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Result Mini - Experiment 1 & 2:

Experiment 1&2 absorb water, which dissolves the material and creates a slimy substance when it dries again

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(19.04.) Experiment 3: (picture 4, bottom)

Petri dish - completely dried out, yellow/corn-coloured, large loss of mass (very flat layer)

Large silver collection dish - completely dried out, yellow „film“

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(19.04) Experiment 3 vol.2: (picture 4 top, picture 5, picture 6)

Petri dish - completely dried out, too solid, breaks

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(19.04.) Experiment 4: (picture 7, picture 8, picture 9)

Petri dish - soft, pliable, brownish yellow, air bubbles

Large silver collection dish - difficult to peel off (carefully!), flexible, only partially stretchable -> tears, beige transparent

PLAN

dry tangerine peel and bark in the oven (sterilising) 


Experiment: Mixture without rice starch

EXPERIMENT 5

10g xanthan

10g banana powder

12.5g glycerol


105ml distilled water


20ml vinegar

(double the amount for preparation)


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PREPARATIONS:

1. measure the distilled water, glycerol & vinegar, pour into a pot and stir together

2. slowly add the banana powder -> stir continuously with a whisk for two minutes at 60 degrees Celsius

3. slowly add the xanthan -> stir continuously with a whisk for two minutes at 60 degrees Celsius

4. whisk for 3 minutes without heat

5. pour into a large Petri dish

6. distribute evenly with a spoon

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OBSERVATIONS:

milky consistency & colour when heated

Consistency - creamy/firm like jelly, beige grey colour when decanting

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EXPECTATIONS:

material that does not break apart, dries, elastic, pliable

AUSBLICK

add the tangerine peel & bark (elm) to the mixture

sterilise in the oven for 90 minutes

03.05.2024

CATCH UP

(19.04.) Experiment 3:

State - unchanged, rock hard, corn coloured

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(19.04.) Experiment 4:

State - flexible, elastic, does not break, smooth surface

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(26.04.) Experiment 5: (picture 1)

State - not dried, same state as when poured, sticky, grey

PLAN

Repeat Experiment 4

Experiment 4 with bark (elm)

Experiment 4 with tangerine peel

EXPERIMENT 6

15g rice starch

5g xanthan

10g banana powder

12.5g glycerol


105ml distilled water


20ml vinegar

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PREPARATIONS:

1. measure the distilled water, glycerol & vinegar, pour into a pot and stir together

2. slowly add rice starch, xanthan gum & banana powder -> stir continuously with a whisk at 60 degrees Celsius

3. pour into a petri dish (square)

4. on baking paper

EXPERIMENT 7

15g powdered bark (elm)

15g rice starch

5g xanthan

10g banana powder

12.5g glycerol


105ml distilled water


20ml vinegar

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PREPARATIONS:

1. measure the distilled water, glycerol & vinegar, pour into a pot and stir together

2. slowly add rice starch, xanthan & banana powder -> stir continuously with a whisk at 60 degrees Celsius

3. add the bark and whisk

4. pour into a petri dish (square)

5. distribute the rest evenly on baking paper

EXPERIMENT 8

15g powdered tangerine peel

15g rice starch

5g xanthan

10g banana powder

12.5g glycerol


105ml distilled water


20ml vinegar

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PREPARATIONS:

1. measure the distilled water, glycerol & vinegar, pour into a pot and stir together

2. slowly add rice starch, xanthan & banana powder -> stir continuously with a whisk at 60 degrees Celsius

3. add the tangerine zest and stir in

4. pour into a petri dish (square)

5. pour on baking paper

6. distribute evenly with a spoon

17.05.2024

CATCH UP

(26.04.) Experiment 5: (picture 1)

State - sticky, firm, pliable, sticks together (handle carefully!), slightly stretchy

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(03.05.) Experiment 6:

State - pliable, elastic, does not break, smooth surface, good consistency

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(03.05.) Experiment 7: (picture 2)

State - hard, not bendable, dark brown, breaks when bent

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(03.05.) Experiment 8: (picture 3, picture 4)

State - pliable and firm, orange colour, good consistency

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Result: Experiment 8 = final recipe

reason: pliable, soft, smooth underside, slightly rough upper side, robust, elastic, comes very close to leather properties

PLAN

Exp. 8: Quantity x3 to achieve a flat surface with a press

Exp. 4 with orange peel instead of tangerine peel

EXPERIMENT 9

26g powdered tangerine peel

45g rice starch

30g xanthan

30g banana powder

38g glycerol


300ml distilled water


60ml vinegar

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PREPARATIONS:

1. measure the distilled water, glycerol & vinegar, pour into a pot and stir together

2. slowly add rice starch, xanthan & banana powder -> stir continuously with a whisk at 60 degrees Celsius

3. shred the tangerine peel

4. add the tangerine peel and stir in

5. pour into a petri dish (square)

6. on baking paper

7. fill into previously lasered  medium-density fibre board (mdf) mould

8. distribute evenly with a spoon

9. put into the  press

10. leave to dry

EXPERIMENT 10

12g powdered orange peel

15g rice starch

5g xanthan

10g banana powder

12.5g glycerol


105ml distilled water


20ml vinegar

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PREPARATIONS:

1. slowly add rice starch, xanthan & banana powder -> stir continuously with a whisk at 60 degrees Celsius

2. add the orange peel and stir in

3. pour into a petri dish (square)

4. pour on baking paper

5. distribute evenly with a spoon

27.05.2024

CATCH UP

(17.05.) Experiment 9:

State - removed from the press: still moist, only slightly dried, left it outside the press, remaining in the mould for further drying

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(17.05.) Experiment 10: (picture 1, picture 2)

State - well dried, elastic, pliable, firm, yellow

10.06.2024 - Open Lab Day

CATCH UP

(17.05.) Experiment 9:

State - well dried, left in the mould - baking paper removed to let it dry further, deep orange, smooth surface, pliable

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Photos of the utensils and results

27.06.2024

CATCH UP

(17.05.) Experiment 9:

State - dried, deep orange, smooth surface, flexible, elastic, cut out from the mould

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Photos of the result

FINAL RESULT

FLYER

UTENSILS

CONCLUSION

At the beginning, the production of the tangerine leather was a bit tricky. We did a lot of experiments to find out what quantities of the various ingredients would produce a satisfactory material of our intention. We were lucky that everything went smoothly and none of the experiments went mouldy. As a result, we were able to do even more experiments.

The tangerine peel gave the material a pleasant texture, firmness and colour. The banana powder, combined with rice starch, provided a certain elasticity that is very similar to that of leather. To summarise, the whole process was a great experience and we are proud of our result.