Processing technology of acetic acid fermented beverage of Xiaobai pear

(1) Product features

It has the health care function of pear and acetic acid fermented beverage and is rich in nutrition. According to traditional Chinese medicine, pear is cold and sweet, which has the effects of moistening the lungs, eliminating phlegm, relieving cough, reducing fire, clearing the heart and so on. Acetic acid produced by acetic acid fermentation has the functions of eliminating fatigue, refreshing, invigorating body and relieving thirst, increasing appetite and so on.

(2) Major primary and secondary branches

Xiaobai pear, Pectinase, wine yeast 145, acetic acid bacteria AS1.41, aspartame (APM), xanthan gum, white granulated sugar, honey.

(3) main equipment

Belt juicer, fruit crusher, constant temperature incubator, shaker, seed tank, saccharification tank, plate and frame filter, air compressor, refrigerator and alcoholization, lactic acid reactor.

(4) technological process

Xiaobai pear → washing → crushing, juice extraction → Pectinase treatment → filtration, residue → adjustment sugar concentration → ethanol fermentation → acetic acid fermentation → pear vinegar → deployment → fine filtration → homogenization → bottle → sterilization → cooling → product

(5) description of operation points

(1) yeast preparation: bevel culture medium, 10 °Bx wort plus 2% Agar, inoculated with yeast, cultured at 28-30 ℃ for 24 hours.

Triangular flask medium (primary seed): 150ml of 10 °Bx wort was placed in 250ml triangular flask, 5% activated bacteria were shaken well, and cultured at 28 °30 ℃ for 24 hours.

Large triangular flask culture (secondary seeds): take 400ml 10 °Bx wort in 5000 ml flask, add 10% wheat bran hydrolysate, add 400ml primary seeds, culture at 28ml 30 ℃ for 18 hours.

Liquid wine mother (tertiary seed): take 140kg of pear juice, add it to a 200L seed tank, add 10% wheat bran hydrolysate, adjust sugar content to 10 °BX, connect 10% secondary seeds, and culture at 28-30 ℃ for 10 hours.

(2) preparation of acetic acid bacteria seeds.

Slant culture: glucose 10g, yeast extract 1g, calcium carbonate 2g, anhydrous ethanol 3.5ml, Agar 2g, adding 100ml distilled water, adjusting pH to 6.5.Acetate bacteria were added and cultured for 48 hours at 30: 32 ℃.

Flask culture: 100ml of the above liquid medium (without Agar) was placed in a 500ml flask, 3.5ml anhydrous ethanol was added, and then connected with the above activated strains of acetic acid bacteria, the inoculation amount was 10%, and the culture was shaken at 30: 32 ℃ for 36 hours.

Large triangular bottle culture: take 4000 ml of pear juice, put it in 5000 ml large triangular bottle, put into 10% triangular bottle acetic acid bacteria culture medium, and culture at 30: 32 ℃ for 20 hours.

(3) preservation method of acetic acid bacteria: liquid seed preservation method. After inoculation and culture, the acidity of the small triangle bottle reached 1.8 × 2.2 g / 100 ml, and about 2% calcium carbonate was added and stored at a low temperature in the refrigerator.

(4) Pectinase treatment of pear juice: 0.12% Pectinase was added to pear juice and incubated at 50-55 ℃ for 2 hours.

(5) the sugar content of pear juice is adjusted: the sugar content is 10%, the reducing sugar is more than 4%, and the acidity (in terms of acetic acid) is about 0.2%.

(6) ethanol fermentation: carried out in a closed tank, the temperature is kept at 28030 ℃, the filling volume is 80%, the fermentation time is about 5 days, the ethanol content of the mature fermentation broth is 5%, the acidity (acetic acid) is about 0.6%, and the residual sugar is controlled at 0.5% 0.8%.

(7) acetic acid fermentation: using liquid submerged fermentation, adding 10% acetic acid bacteria culture liquid, constantly stirring and ventilating, ventilation as fermentation broth: air volume = 1 0.06 / 0.08, which is controlled in three stages.

Prophase: the temperature of the tank is controlled at 32-34 ℃, the air volume is small, and the time is about 24 hours.

Mid-term: increase the air supply, the temperature is 3435 ℃, the time is about 16 hours.

In the later stage, 33 ℃, about 20 hours, it is appropriate to determine that the acidity in the fermentation broth no longer rises.

(8) blending: add 0.03%APM, 0.2% xanthan gum, honey and white granulated sugar.

(9) homogenization: the feed liquid is heated to 50 ℃ homogenization, the first homogenization pressure is 18 MPA, and the second homogenization pressure is 25 MPA.

(10) Sterilization: after filling, sterilization at 85 ℃ for 15 minutes for 20 minutes.

(6) Product quality indicators

Total sugar (glucose) 6%-8%; total acid (acetic acid) 0.3%-0.5%; soluble solids 8%-10%.