Experimental materials:

Medium-sized ripe purple grapes

Fine sugar 40-60 grams of fine sugar per 500 grams of grapes.

The amount of vinegar koji or rice vinegar is 5% of grape juice (vinegar koji is added according to the instructions).

How to make wine:

First, pre-fermentation is carried out in an environment of 25-28 degrees.

1. Prepare a sterilized clay pot or jar, preferably dark and opaque. Rinse with clean water first, and then disinfect with 70% alcohol by volume.

2. Wash the grapes with water, and don't use chemicals such as detergents. After drying, put your hand into the jar and crush three or two grains together. Cover and ferment for one day.

3. Add half of the sugar and stir evenly the next day, add the other half of the sugar and stir evenly after three days of fermentation, and then ferment for another three days.

4. Use clean chopsticks or spoons to press the floating grape skins below the liquid level once or twice a day.

5. At this point, the pre-fermentation is over. Filter out grape juice with siphon and filter cloth.

Secondly, after the pre-fermentation, the post-fermentation was carried out at 18-25℃.

1. After the pre-fermentation, put the juice into a light-proof glass bottle, cover it and let it stand for 12 hours, and then seal it for post-fermentation.

2.30 days later, when you open the wine, you can find that the liquor becomes clear, and there is a layer of sediment at the bottom, which is the "corpse" and impurity of yeast after completing its historical mission. This layer is used in industry to make yeast puree.

3. Purify the pure liquid on the upper layer again by siphoning or filtering. Fill in opaque wine bottles, and then seal and store for half a year until the wine is mature.

Vinegar making: ferment at 30-35℃.

1. Mix a portion of wine with a portion of boiled water and cool it, then add a proper amount of vinegar koji or 5% rice vinegar as the base material according to the instructions, put it in a jar, open the lid and ferment, and cover it with a layer of gauze to prevent insects.

2. Ferment for 3-4 days after a complete layer of acetic acid bacteria white film is produced on the surface. (I fermented it for 6 days after 22 degrees. )

3. Finally, filter out the clarified vinegar, put it into the pot, boil it until there are sparse bubbles along the edge of the pot, turn off the fire, bottle it while it is hot and seal it.

Production technology of fruit wine

I. The purpose of the experiment

Learn to make wine from grapes and know its principle.

Two. Experimental principle

Using the anaerobic respiration of yeast to produce alcohol and make fruit wine.

Three. Materials and appliances

Grape, 70% alcohol, prepared potassium dichromate solution, 3mol/L sulfuric acid solution, test tube, test tube clamp, measuring cylinder (5ml) cotton ball, juicer, special alcohol fermentation device and thermometer.

4. Production steps

1. Selection and treatment of materials

Selecting fresh grapes, cleaning, pruning and juicing.

2. Disinfection and sterilization of experimental equipment

(1) The juicer should be cleaned and disinfected with 70% alcohol.

(2) Filling: the treated grapes are filled into two thirds of a special fermentation container and sealed.

3. Control fermentation conditions

The fermentation temperature is controlled in the range of 18-25 degrees Celsius for about 10- 12 days.

4. Take quantitative fermentation broth and potassium dichromate detection solution for testing every day, observe the color change and make records.

Verb (abbreviation of verb) results and analysis

According to the daily inspection, summarize the situation of alcohol fermentation and study and adjust the fermentation conditions in time.