SU762840A1 - Method for drying fruit husk - Google Patents

Description

The invention relates to a method of drying fruit juice, mainly citrus, and can be used in the food industry, especially in the manufacture of citrus powder for sweets, cookies, jelly, puddings and syrups.

There is a drying method that involves blowing the particles of the product with hot air in two stages, with the temperature at the first stage —_ 140-150 ° С, and the second stage — 98-100 ° C _? [£ 1.

The disadvantage of this method is that the quality of the product 15 deteriorates, as it is exposed to the high temperatures necessary for removing moisture from the inner layers of the product for a long time. The process proceeds for a long time due to the fact that during convective drying, thermal diffusion prevents the movement of moisture from the inner layers of the product to the surface, since the temperature inside the product is lower than on its surface.

The aim of the invention is to obtain a high-quality product by intensifying the process of moisture transfer from the inner layers of the product to! surface. thirty

This goal is achieved by the fact that when forming the squeeze is heated to 80-90 ° C, and hot air is blown at the first stage for 50-60 minutes at an air temperature of 98-100 ° C, and at the second stage, 25-30 min at air temperature 5060 ° С. In addition, the moisture content of air during the entire blowing is 10-15 g of water per 1 kg of dry air.

Preheating the squeeze before blowing hot air reduces the temperature difference between the inner and surface layers of the product, thereby intensifying the process of moisture transfer from the inner ^ layers of the product to the surface, since thermal diffusion practically does not affect the movement of moisture ^ inside the material. The temperature of the coolant, not exceeding 100 ° C, provides high-quality dry citrus marc and intensive process management. Exceeding it adversely affects the quality of dry marc. Application for blowing in the first stage of air with a moisture content of 10-15 g of water per 1 kg of dry air, dripping at the speed of its movement 762840

2.5-3.5 m / s creates the best conditions for heat transfer and allows you to finish the first stage in 50-60 minutes. ”The moisture content of the surface layers of the husks at the end of the first stage is 1012%. To preserve vitamins vyzhim- <Kah air temperature in the second sta- ^e days blowing was decreased to 50-60 ° C, which corresponds to the limit of thermal stability of the product at a moisture content of 10-12%. After the evaporation zone is deepened into the product, the driving forces of the drying process are the forces of internal mass transfer, to which the speed of movement of the heat SITC does not have a significant effect. ^four

influence. Therefore, in order to reduce energy consumption, as well as to prevent the possible carry-over of individual dried particles of the product from its surface, the speed of air in the second stage is reduced to 1.5-2.0 m / s.

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Example 1. Tangerine husks are formed on metal pallets in the form of cylinders with a diameter of 7 mm and at the same time heated to 80 ° C.

Then the squeeze trays are placed in 25

"the dryer, where it is blown by a stream, of air in the first stage at 98 ° C and at a speed of 2.5 m / s for 60 minutes."

In the second stage of blowing, the air temperature is reduced to 60 ° C and the speed is up to 1.5 m / s. After blowing for 30 '25 min, the husks acquire the required moisture (6%) and drying is considered complete. Moisture content of air, while blowing - 10-15 g of water per 1 kg of dry air. 35

Example 2. The method is carried out as in example 1, but the husks are heated to 90 ° C; air temperature -

100 and 50 ° C, air speed 3.5 and

2.0 m / s, duration 50 / I and 30 minutes, respectively, of the first and second stage of blowing, the final moisture content of the residue is 4%

The proposed method provides high-quality drying of citrus marc, while After this, a light yellow powder with high taste and nutritional properties is obtained. "" "" ""

The annual economic effect from the introduction of the proposed method of drying is 95 thousand rubles.

Claims (2)

Claim 1. The method of drying fruit juice, mainly citrus, involving the molding of a squeeze in the form of cylindrical bodies and blowing them with hot air in two stages, characterized in that, in order to obtain a high-quality product by intensifying the process of moisture transfer from the inner layers of the product to the surface, during molding, the squeeze is heated to 80-90 ° C, and hot air is blown at the first stage for 50.60 minutes at an air temperature of 98100 ° C, and at the second stage - for 2530 minutes at an air temperature of 50 ° 60 ° . 2. The method according to π.1, from l and tea to the fact that the moisture content of air during the entire blow is 10-15 ~ г g of water per 1 kg of dry air.