First Experiment
First Experiment
-How does the ratio of milk to water affect the softness and appearance of bread?
Before Cooking-6Ws
1. Who?
This experiment is designed and carried out by myself. This is to minimize the errors created in the experiment, including the kneading strength.
This experiment is designed and carried out by myself. This is to minimize the errors created in the experiment, including the kneading strength.
2. Where?
The ingredients are bought in the supermarket.
This experiment took place in the dining room of my home.
3. When?
I did the experiment on 27th March 2020 from 15:00-19:30.
4. What?
Ingredients that I used:
Apparatus that I used:
Why do I investigate the effect of the ratio of milk to water?
Liquid is an important ingredient in bread making. The type of liquid used will have a great impact on the overall quality of the bread. Therefore, I would like to see how different types of liquid affect the texture and appearance of bread.
Why do I choose the softness and appearance of bread as the dependent variable?
Why do I choose the softness and appearance of bread as the dependent variable?
First, the texture is difficult to measure. One of the most direct ways to measure their texture is comparing their softness. This can be done by observing the number and size of bubbles and comparing the thickness of bread after compression with the same strength after the bread is being sliced.
Second, the presence of lactose in milk may also cause changes in the colour of the crust, which the most significant variable. The golden brown colour would be desirable and attractive for bakery products.
6. How?
How to do the experiment?
The ratio of milk to water of starter is changed, while the amount of ingredients of the dough is kept the same. The dough is divided into 4 equal portions after mixing the ingredients and the starters with different milk to water ratio (M to W ratio) is added accordingly.
How to measure the result?
Compare the colour of the crust after cooling. Slice the bread to observe the number and size of bubbles and compare the thickness of bread after compression with the same strength.
While Cooking
(1) Milk is used as all liquid.
(2) M to W ratio of 5:1
(3) M to W ratio of 2:1
(4) M to W ratio of 1:2
1. Starters with different milk to water ratio is mixed.
2. A big dough is mixed.
3. The dough is divided into 4 equal portions. Starters are added and mixed thoroughly. Then, cover them with cling wrap.
5. Knead each dough into a ball shape and place them onto a tin plate.
6. Bake the dough in a 175°C oven for 35-40 minutes until the top of the bread is golden brown.
7. Allow the bread to cool to room temperature.
After Cooking
Observation
1. Softness of the bread: Number and size of bubbles
The bread with most milk content has the highest amount and largest air bubbles. There is a significant air bubble below the bread crust. Meanwhile, the number and size of air bubbles decreases with reducing the ratio of milk to water.
2. Softness of the bread: Thickness of bread after compression
Ratio of milk to water
|
Thickness of bread after compression
|
Milk used as all liquid
|
2.8 cm
|
5:1
|
3.1 cm
|
2:1
|
3.3 cm
|
1:2
|
3.5 cm
|
From the above table, when applying the same force to the bread, the bread with most milk content is the thinnest, while the bread with milk to water ratio 2:1 and 1:2 have a similar thickness. This shows that the higher the milk to water ratio, the thinner the bread when compressed with the same force, the softer the bread.
Ratio of milk to water
|
Colour of the crust
|
Milk used as all liquid
|
Dark brown
|
5:1
|
Brown
|
2:1
|
Brown
|
1:2
|
Light brown
|
As seen from the picture, the bread with the lowest milk to water ratio has the lightest colour, while the bread with the highest milk to water ratio has the darkest colour. Also, Bread with milk to water ratio 5:1 and 2:1 have similar crust colour. This shows that the higher the milk to water ratio, the darker the colour of bread crust.
Data Analysis
From the above observation and measurement, it is significant that the softness and colour intensity increases with increasing milk to water ratio. This implies that milk does improve the overall quality, including the texture and appearance of bread. This may be due to the presence of lactose and milk fat in milk. Lactose in milk has little sweetening power and caramelize quickly in the oven, forming a darker crust. Meanwhile, milk fat forms an extensible thin film that stabilize gas bubbles during fermentation, forming increased softness.
Source of errors and improvements
1. Ingredients stuck on the spatula or in the container
As the dough could be sticky, some of it would be left on the spatula or in the container. When the dough is being transferred from one container to the other, some of the dough may are not baked. In order to minimize the error, I would add more flour during kneading to prevent the dough from sticking on the spatula and in the container.
As the dough could be sticky, some of it would be left on the spatula or in the container. When the dough is being transferred from one container to the other, some of the dough may are not baked. In order to minimize the error, I would add more flour during kneading to prevent the dough from sticking on the spatula and in the container.
2. Portion of dough divided
In step 3, the dough needs to be separated into 4 equal portions. However, I separated it without thorough mixing. There may be an uneven distribution of ingredients inside the container and have insufficient amount of ingredients in one of the breads. To minimize the error, the dough has to be kneaded and mixed thoroughly until no grain is present.
In step 3, the dough needs to be separated into 4 equal portions. However, I separated it without thorough mixing. There may be an uneven distribution of ingredients inside the container and have insufficient amount of ingredients in one of the breads. To minimize the error, the dough has to be kneaded and mixed thoroughly until no grain is present.
3. Time for fermentation
During kneading, I treated the dough one by one. Therefore, time used for the dough to ferment could be slightly different. The dough with longer fermentation time may raise higher, which may affect the investigate result especially fermentation time is the cause of having different softness. To minimize this error, I would minimize the processing time by asking for help or use machines.
During kneading, I treated the dough one by one. Therefore, time used for the dough to ferment could be slightly different. The dough with longer fermentation time may raise higher, which may affect the investigate result especially fermentation time is the cause of having different softness. To minimize this error, I would minimize the processing time by asking for help or use machines.
4. Baking position
During baking, the heating wire of the oven cannot be adjusted, while it is mainly located at the back and middle of the oven. This may cause uneven distribution of heat, leading to the uneven colour of crust. To minimize this error, I would rotate the baking plate when the baking process is halfly finished.
During baking, the heating wire of the oven cannot be adjusted, while it is mainly located at the back and middle of the oven. This may cause uneven distribution of heat, leading to the uneven colour of crust. To minimize this error, I would rotate the baking plate when the baking process is halfly finished.
5. Measurement error
When measuring the thickness of bread after being compressed, only the height of the bread is measured. However, there may be a difference in size when kneading the dough in a ball shape. Also, the shape would be changed after fermentation. To minimize the error, the width of each bread should keep the same or similar. Only the height of the dough would be increased.
When measuring the thickness of bread after being compressed, only the height of the bread is measured. However, there may be a difference in size when kneading the dough in a ball shape. Also, the shape would be changed after fermentation. To minimize the error, the width of each bread should keep the same or similar. Only the height of the dough would be increased.
Comments
Post a Comment