Processing Technology of Chestnut Tea

(1) Overview

Chinese chestnut is a famous dried fruit in China with rich nutrition, high amylopectin content, delicate powder, sweet and waxy crisp raw and cooked food and excellent flavor. Chinese chestnut also has a high role in medical and health care, which is contained in the ancient book "Southern Yunnan Materia Medica". Chestnut has the effect of tonifying qi, thickening intestines and stomach, tonifying kidney, strengthening muscles and promoting blood circulation.

(2) Raw materials and formulations

Chestnut: 15%:

Carrots: 3%

Sugar: 4%

Milk powder: 2.5%

Ethyl maltol: 0.02%

Xanthan gum: 0.35%

Drinking water: excess.

(3) technological process

Chestnut → peeling → underwear removal → color protection → pre-cooking → beating (cooked carrot slices, mixed syrup) → grinding → blending → homogenization → degassing → filling → sterilization → inspection

(4) main points of operation

① peeling, underwear removal, color protection: use a peeling machine or manual peeling. Before peeling, the chestnut should be exposed to the sun for 6 hours for 10 hours, or 150 to 180 ℃ high temperature chain baking for 20 seconds for 25 seconds to make the chestnut shell crack. The machinery in direct contact with the chestnut during the peeling process should be made of stainless steel to prevent browning; using the lye corrosion polishing method, the shelled chestnut should be put into a sodium hydroxide solution with a concentration of 6% 0.8% and a temperature of 90: 95 ℃ (the weight ratio of chestnut to lye is 1:2) for 2 minutes, while passivating the enzyme activity in the surface fruit. Quickly remove and wash the lye after corrosion, transfer to a barrel grinder to remove underwear; rinse the underwear with tap water and neutralize it with 2%-4% dilute hydrochloric acid solution for 4-6 minutes. Remove it and put it into the color protection solution (the composition of the color protection solution is 0.1% citric acid, 0.1% sodium chloride, 0.05% disodium ethylenediamine tetraacetate).

② pre-cooking: remove the chestnut from the color protection solution and boil it in the boiling precooking solution for 40 minutes (the weight ratio of the precooking liquid to the chestnut seed is 3:2, the composition of the boiling liquid is 15% sucrose, 0.05% sodium chloride, 0.12% disodium ethylenediamine tetraacetate, 0.1% citric acid).

③ preparation of cooked carrot slices: carrots remove roots, disease spots, etc., wash and cut into thin slices of about 3mm. Cook 11O ℃ in a pressure cooker for 20 minutes. Cool and set aside.

④ preparation of mixed syrup: sucrose, maltose and liquid glucose are weighed according to the dosage and formula. First of all, 100 kg of sucrose and 50 kg of water are heated and dissolved, and then maltose and liquid glucose are added. Heat to boil and keep above 80 ℃ for 10 minutes.

⑤ beating and grinding: mix boiled corn seeds, carrot slices and mixed syrup and beat it with a beater with a sieve diameter of 0.2mm. After beating, further grind the pulp with colloid and transfer it to a mixing tank.

⑥ preparation: according to the formula, take milk powder, ethyl maltol, xanthan gum and other auxiliary materials, fully mix and transfer to the mixing tank. Turn on the mixer and mix all kinds of raw and auxiliary materials in the cylinder evenly.

⑦ homogenization: homogenization with high pressure homogenizer at 18 ~ 22 MPA. The material produces hole effect, shear effect and collision effect under high pressure, and the fineness is less than 1 ~ 2 microns.

⑧ degassing, filling, sterilization: in order to prevent oxidation and browning of finished products, vacuum degassing is carried out before filling. The conditions are as follows: temperature 35: 45 ℃, vacuum 90.6 ~ 96.0 KPA, time 10 minutes, automatic filling. Seal in time after filling. The size of the tank is 250ml, the vacuum degree of the sealing process is 0.03mm / 0.035mpa, and the sterilization formula is 10mm / 39mm / 10ml / 39mm / 10ml / 10ml / 10ml, the vacuum degree of the sealing process is 0.03mm / 0.035mpa, and the sterilization formula is 100 ℃. It was quickly cooled to 40 ℃ after sterilization and kept for 7 days after 25 ℃.

⑨ inspection out of the factory: after heat preservation, sample inspection is carried out according to the standard inspection procedures and methods, and the packaging leaves the factory after passing the inspection.

(5) quality standards

1. Sensory index

Color: light yellow to orange

Tissue morphology: uniform turbid liquid, thick feeling, no impurities, no precipitation delamination for a long time

Taste and smell: with chestnut fruit tea due to the chestnut aroma, carrot flavor is obvious, sweetness palatable, no peculiar smell.

2. Physical and chemical index

Net capacity: 250ml, allowable tolerance ±3%, but the average volume per batch shall not be lower than the specified volume

Soluble solids (in terms of refraction): 18% 22%

Insoluble solids: 78%.