Juice processing technology

One. Get the juice

The pretreatment is pre-treatment, including selection, washing, crushing, heat treatment, etc.

Two. Juice

1. The juice of fruit is squeezed and leach two kinds, with meat juice can use slurry method.

2. Most fruit juice is rich in juice, commonly used for pressing, called "juicing"

3. Only fruit with less juice can be used in the extraction method, such as hawthorn, plum, date and so on.

4. Berries: direct slurry.

The yield of fruit

3. Screen

The aim is to remove the coarse particles and suspended objects in the juice.

1. Their presence can affect the state and flavor of the juice, and make the juice change easily.

2. Coarse filtration can be combined with juicing and can be carried out separately. The diameter of filter hole is about 0.5mm (100-200 mesh)

Iv. Clarification of juice

Clarify the object

1. Suspensions include color granules and other fine particles. Visible to the naked eye, it is the granules formed after the breakdown of the tissues, whose composition is mainly: cellulose, hemicellulose, glycosides, bitter substances, enzymes, etc.

2. The colloidal particle is contained pectic substances, gumminess and protein particles, not visible to the naked eye, can temporarily are transparent state in the fruit juice, but them with different charge, precipitation will gradually gathered, muddy juice.

Clarification method

1. Enzymatic clarification

2. Gelatin -- tannin clarification

3. Enzyme and gelatin joint clarification method

4. Other clarifications.

Filtering five.

The clarified juice must be filtered to remove the tiny suspension. Common equipment: bag filter, fiber filter, plate frame filter, vacuum filter, centrifuge, etc. The diatomite filter, plate frame filter, centrifuge separator and vacuum filter are used in juice production.

6. Adjustment and mixing

Determine the minimum juice content and determine the formula according to the required solid acid ratio. Sugar acid adjustment:

X=[W (b-c)] / (d-b) X: the amount of concentrated sugar that needs to be added (kg)

D: concentration of concentrated sugar (%), W: before adjusting the weight of the juice (kg), C: before adjusting the sugar content of the former juice (%)

B: the required amount of sugar after adjustment (%)

Seven homogeneous.

In order to prevent the separation of solid liquid when processing turbidity or meat juice, homogeneous treatment must be carried out. Homogenization - the gap between the seat and stem of the valve through the homogenizer at high pressure, and the fine particles are further broken, the pectin and the juice are close, and the homogeneity is maintained. Average pressure is generally 15-40mpa.

Eight degassing.

The purpose of degassing is to remove the oxygen, remove the gas from the suspended particles, reduce the tank and sterilization, and reduce the corrosion of the inner wall of the tank.

Degassing method: 1. Vacuum degassing - intermittent continuous type. Continuous centrifugal sprinkler head: spray type, centrifugal and film type.

2. Displacement method: adsorption gas is excluded by the replacement of inert gases such as N2/ CO2.

3. Chemical degasification method: the use of antioxidant or oxygen - like enzymes as a removal agent is added to the juice. Such as ascorbic acid, glucose oxidase.

Concentrated nine.

Purpose: 1. Reduce capacity, save packaging and transportation expenses. Quality is more consistent. 3. Increase sugar and acid content and increase the storage of products. 4. The concentrated juice is versatile and can be used as the base material for various foods.

Methods: the method of concentration is divided into vacuum concentration, reverse osmosis, ultrafiltration concentration and freezing concentration.

10. Aromatic recycling

Purpose: in the process of heating concentration, some typical aromatic substances in fruit with the moisture evaporation and escape, so that the concentration products lose the original natural, gentle flavor, therefore, it is necessary to put these material recycle and concentration, and then added to the juice.

The technical route: 1. The first is to separate the aromatic ingredients before they are concentrated, and then add them to the concentrated juice. 2. One is to separate the vaporized steam from the tank and recycle it, then add it back to the juice.

Eleven. Dry fruit juice

Purpose: 1. Low water content can prolong the storage period and save transportation and packaging costs. 2. After processing and making fruit powder, the application range of fruit raw materials was broadened. 3. Super fine fruit powder is more convenient to eat, the nutrient composition is easier to digest, and the taste is good.

Drying: vacuum drying, foaming drying, spray drying, fluidized bed drying.

12. Juice sterilization

Fruit juice sterilization: aim to kill microorganisms, prevent fermentation, passivate various enzymes and avoid undesirable changes.

Sterilization: high temperature short time sterilization (60-90 - s under 88 ℃) instantaneous ultra high temperature sterilization. 107 ~ 116 ℃ under 2 ~ 3 s)