Lab 8 making

Lab 8 making

 

1. Tutorial Purpose

L deepen understanding of the basic principles and general processes and methods of Bread Production.

L conduct an Exploratory Test on the preparation of standard powdered bread as raw material, as well as adding auxiliary materials or using a fermentation method to observe its impact on the quality of the finished product.

 

2. Experimental Equipment and raw and auxiliary materials

2.1Lab Equipment

Dough generator, splitter, kneading machine, forming machine, sending cabinet, oven, electronic scale, stainless steel cutter, baking die, Baking Plate, electric furnace, etc.

 

2.2Raw and auxiliary materials

Special powder, standard powder, yeast, salt, oil, fresh eggs, sugar, modifier, milk powder, vegetable oil

 

3. experiment content

 

3.1 basic processes and methods for making breads

3.1.1 Formula

Specially crafted powder 100

Fresh yeast, 1.0

Sugar 12

Precision salt 0.5

Vegetable oil 1.0

Water 50

3.1.2 Test Procedure

First powder adjustment first fermentation → second powder adjustment → first fermentation shaping → xingfa → baking → cool-down → finished product inspection →

3.1.3 operation points

① First powder adjustment:

Take 80% of the flour, 70% of the water and all yeast (water-soluble with a small amount of 30-36 ℃ in advance) together into the powder regulator, first Slow stirring, after mixing materials, stir them at medium speed for about 10 minutes to make the materials fully reinforced into a thick and smooth yeast dough, the prepared dough temperature should be at 30-32 ℃ (visible when the flour temperature is adjusted with water temperature required by rice ).

② First fermentation:

Insert a thermometer into the dough, put it in a 32 ℃ Constant Temperature Incubator container, static fermentation 2-hours, observe the fermentation maturity (initiated by the dough with a hand gently pressed to slightly collapse) it can be extracted. Note that the dough temperature during fermentation should not exceed 33 ℃.

③ Second powder adjustment:

The remaining raw materials (sugar, salt, and other solids should first be dissolved with water) and the dough after the above fermentation mature together with the powder regulator. Mix slowly and then stir at medium speed for 10-12 minutes. Become smooth and uniform dough.

④ Second fermentation:

The method is the same as the first time. The time is about 1.5-2 hours.

⑤ Integer

After the second fermentation, the dough was made into a stainless steel knife and cut into about 150 grams of green dough. the dough was squashed to remove the gas from the dough. After shaping the dough, the dough was filled with a thin layer of oil coated on the inner wall, then, apply sugar water or egg on the surface of the billet with a small batch of pens.

6. xingfa:

The baking mould with green billet is placed in the temperature control and humidity control box. The temperature in the box is adjusted to 30 ℃, the relative humidity is 90-95%, and the waking time is 45 minutes-1.0 hours, generally, we observe that the highest point initiated by the Green billet is slightly higher, and the upper port of the baking die will wake up and mature, so we can immediately go to the place.

7. Baking:

The blank should be immediately placed on the baking tray, pushed into the oven of far infrared food whose temperature has been pushed to about 250 ℃. At first, only the bottom fire is enabled, and the surface fire is not enabled, the temperature in the furnace can gradually decrease. observe that the surface fire will be opened immediately when the green billet in the furnace is initiated to the desired height (the door can be quickly opened for observation), and the temperature will rise again, when you observe that the surface color of the bread is slightly lighter than the expected color, turn off the surface fire and continue the heating at the bottom fire. At this time, the temperature can be basically balanced until the bread is cooked and then immediately go to the place, generally, it is observed that direct steam occurs in the outlet of the oven, and the total baking time reaches 15 to 16 minutes. Note that the temperature fluctuation during baking should be controlled between 2400-260 ℃.

Refer cooling:

The baked bread is dragged out of the baking mould after being cooler, and naturally cools down to room temperature in the air.

Finished product quality inspection:

Inspection Method inspection items

Sensory inspection form, color, internal tissue

Taste, hygiene

Physical and chemical testing of acidity and moisture

 

3.2 experiment on making bread with standard powder

At present, most of the flour used for making bread in China is standard powder and special powder. Because the gluten and ash content of the two are different, they are used as raw materials to add other similar auxiliary materials, the quality of the finished bread made under the same process conditions and operation methods is very different. Through this experiment, the quality of the finished bread is compared with the above 3.1, you can make a comparison.

The formula and steps of this experiment are the same as those of 3.1 except for the standard powder used in the above 3.1 formula.

 

3.3 Add superior accessories for making bread Experiment

In order to improve the nutritional value of the bread and add a good color and flavor, it is often used to add egg products, dairy products, and other superior auxiliary materials to the bread. In this way, it will have a certain impact on all the operations of making the bread. Through this experiment, we can observe its effect in comparison with the above 3.1.

 

4 questions

① What are the requirements for flour raw materials for making bread? Why?

② Why does the factory usually use secondary fermentation to produce bread? In this experiment, which method do you think is appropriate? Why?

③ What is the impact on the package quality of sugar, dairy products, egg products and other auxiliary materials?

④ Why should the surface fire be opened for a while later than the base fire during the baking?