CN106490132A - Using the infrared method for carrying out pomace drying of intermediate waves - Google Patents

Abstract

The invention discloses a method for drying fruit pomace by using medium-short-wave infrared, which includes: using medium-short-wave infrared radiation with a wavelength of 1-4μm and a radiation power of 900-1350W to irradiate pomace for the first stage of treatment, wherein the radiation distance The temperature is 8-12cm, the temperature is 70-80°C, and the irradiation time is 4-5h. The method for rapidly drying fruit pomace provided by the present invention has the advantages of short drying time, fast drying speed, simple operation, easy control, low investment cost and the like. The final water content of pomace dried by the method provided by the invention is controlled below 10%, and the water activity is low, which is not conducive to the growth and reproduction of microorganisms, and can be stored for a long time, providing guarantee for the transportation and subsequent processing and utilization of pomace .

Description

Method for drying pomace by using medium and short wave infrared

technical field

The invention belongs to the technical field of agricultural product processing, and relates to a method for drying pomace by using medium and short wave infrared.

Background technique

my country is the world's largest producer and exporter of fruit, with an annual output of more than 100 million tons of fruit, and has always maintained a rapid growth trend. Pomace is the waste residue left after plant fruit is squeezed to extract its juice or oil, and it is an important by-product of the fruit processing industry. Pomace mainly includes fruit peel, pulp, fruit seeds, etc. It is rich in pectin, dietary fiber, polyphenols, flavonoids and other nutrients, and has a very high reuse value. However, the level of processing and reuse of pomace in my country is significantly lower than that of developed countries. Except for a very small part used to produce feed, most of them are directly abandoned, which not only causes a huge waste of resources, but also seriously pollutes the environment.

Drying is an essential step before pomace is further processed. Pomace has a high water content and a lot of soluble substances, and it is easy to spoil in a short period of time, making it difficult to store and transport. Dried pomace is not only convenient for storage and transportation, but also beneficial to the subsequent processing of pomace and improving the commerciality of pomace. At present, traditional methods such as natural drying and hot air drying are usually used for drying pomace in my country, which have problems such as long production cycle, high cost, high energy consumption, and serious loss of nutrients. The quality of the produced pomace is poor, and it is difficult to meet the requirements of further intensive processing, which makes it difficult to reflect the added value of pomace products. It can be said that pomace drying is a technical bottleneck restricting the reprocessing and utilization of pomace in my country.

At present, there are research reports on the drying method of pomace. For example, methods such as utilizing rotary cylinder drier, air flow drier and air drying are used to dry pomace, but these methods have certain defects. The disadvantage of the rotary cylinder dryer is that the filling factor of the material, that is, the ratio of the volume of the material to the volume of the cylinder is small. Therefore, generally in the case of large output, the diameter and length of the cylinder are relatively large. In addition, there are many transmission parts, which require frequent maintenance. And it is not suitable for drying viscous materials, otherwise the phenomenon of wall sticking will occur; the disadvantage of the airflow dryer is that it is not suitable for large-scale continuous production, and the drying cost is high; Dust, sand and other pollutants, and the processing cycle is very long, requires a lot of manpower and material resources, covers a large area, and the efficiency is very low. The most important thing is that this method will be affected by the weather. If it is rainy, If the pomace cannot be dried in time, it will deteriorate and can only be discarded as waste.

Contents of the invention

An object of the present invention is to solve at least the above problems and/or disadvantages and to provide at least the advantages as will be described hereinafter.

Yet another object of the present invention is to provide a method for drying pomace using medium and short wave infrared.

For this reason, the technical scheme provided by the invention is:

A method of drying pomace using short and medium wave infrared, comprising:

The pomace is irradiated by mid-short wave infrared with a wavelength of 1-4μm and a radiation power of 900-1350W for the first stage of treatment, wherein the radiation distance is 8-12cm, the temperature is 70-80°C, and the irradiation time is 4-5h .

Preferably, in the method for drying pomace by using mid-short wave infrared, when performing the first-stage treatment, the pomace is spread flat on a drying rack, and the thickness of the pomace is 0.5-1.5 cm.

Preferably, in the method for drying pomace by using mid-short wave infrared, the first-stage treatment also includes a dehumidification process, and the dehumidification fan has a wind speed of 2-3m/s.

Preferably, in the method for drying pomace by using mid-short wave infrared, the moisture content of the pomace to be dried is 75-85%.

Preferably, in the method for drying pomace by using mid-short wave infrared, the pomace is the pomace left after screw pressing, belt pressing or screw pressing.

Preferably, in the method for drying pomace by using mid-short wave infrared, the pomace is apple pomace, peach pomace, citrus pomace, pear pomace, grape pomace, tomato pomace and carrot pomace Any one or several types of slag.

Preferably, in the described method of utilizing mid-short wave infrared to dry pomace, after the first-stage treatment, it also includes sequentially:

The second stage of treatment: irradiate pomace with medium-wave infrared radiation with a wavelength of 2-3μm and a radiation power of 1000-1250W. The radiation distance is 10-15cm, the temperature is 60-70℃, and the irradiation time is 10-20min. The thickness of pomace is 1-3cm;

The third stage of treatment: using short-wave infrared radiation with a wavelength of 0.7-1μm and a radiation power of 1200-1350W to irradiate pomace, the radiation distance is 12-15cm, the temperature is 50-60℃, and the irradiation time is 5-15min. The thickness of pomace is 2-5cm.

The present invention at least includes the following beneficial effects:

The method for rapidly drying fruit pomace provided by the present invention has the advantages of short drying time, fast drying speed, simple operation, easy control, low investment cost and the like. The final water content of pomace dried by the method provided by the invention is controlled below 10%, and the water activity is low, which is not conducive to the growth and reproduction of microorganisms, and can be stored for a long time, providing guarantee for the transportation and subsequent processing and utilization of pomace .

Other advantages, objectives and features of the present invention will partly be embodied through the following descriptions, and partly will be understood by those skilled in the art through the study and practice of the present invention.

detailed description

The present invention will be further described in detail below in conjunction with the embodiments, so that those skilled in the art can implement it with reference to the description.

It should be understood that terms such as "having", "comprising" and "including" as used herein do not entail the presence or addition of one or more other elements or combinations thereof.

The invention provides a method for drying pomace by using medium and short wave infrared, comprising:

The pomace is irradiated by mid-short wave infrared with a wavelength of 1-4μm and a radiation power of 900-1350W for the first stage of treatment, wherein the radiation distance is 8-12cm, the temperature is 70-80°C, and the irradiation time is 4-5h .

Different from the drying of simple solid or liquid substances, since the pomace contains both solid and liquid, and has a certain viscosity, the method of medium and short wave drying is also different from the drying of substances with a single material form. In the present invention, in order to ensure that the fruit pomace can be quickly dried, reduce energy consumption, keep its nutritional components from being lost, and then promote the postharvest synthesis of certain nutritional components in it, the present invention utilizes short- and medium-wave infrared radiation to irradiate the pomace. After the stage treatment is completed, the water content in the treated pomace can be lower than 10% (mass fraction), the water activity is lower than 0.6, and the retention rate of polyphenol components is higher than 80%.

In one embodiment of the present invention, preferably, when performing the first-stage treatment, the pomace is spread on a drying rack, and the thickness of the pomace is 0.5-1.5 cm.

In one of the embodiments of the present invention, as a preference, the first-stage treatment further includes a dehumidification process, and the dehumidification fan has a wind speed of 2-3 m/s.

In one embodiment of the present invention, preferably, the moisture content of the pomace to be dried is 75-85%.

In some embodiments of the present invention, preferably, the pomace is the pomace left after screw pressing, belt pressing, or screw pressing, including but not limited to these sources.

In some embodiments of the present invention, preferably, the pomace is any one of apple pomace, peach pomace, citrus pomace, pear pomace, grape pomace, tomato pomace and carrot pomace or Several kinds.

In some embodiments of the present invention, as a preference, after the first stage of treatment, it also includes sequentially:

The second stage of treatment: irradiate pomace with medium-wave infrared radiation with a wavelength of 2-3μm and a radiation power of 1000-1250W. The radiation distance is 10-15cm, the temperature is 60-70℃, and the irradiation time is 10-20min. The thickness of pomace is 1-3cm;

The third stage of treatment: using short-wave infrared radiation with a wavelength of 0.7-1μm and a radiation power of 1200-1350W to irradiate pomace, the radiation distance is 12-15cm, the temperature is 50-60℃, and the irradiation time is 5-15min. The thickness of pomace is 2-5cm.

After the first-stage treatment, further, in order to make the pomace have lower water content and lower water activity, the second-stage treatment can be carried out to continue to dry the water and kill microorganisms. At the same time, the second-stage treatment has It is beneficial to the synthesis of certain nutrients in pomace, such as polyphenols, sugars, flavonols, etc. The third stage of treatment can kill microorganisms in pomace, and further promote the synthesis of polyphenols, sugars, and flavonols. At the same time, the temperature gradient in the first, second and third stages gradually decreases, which facilitates the cooling of the slag after treatment and improves the processing efficiency.

Example 1

Medium and short wave infrared fast drying peach residue

Dry peach pomace as follows:

(1) Peach (the kind is Okubo) obtains peach skin dregs after screw pressing, and the moisture content is 85%;

(2) spread the peach residue obtained in step (1) on the mesh tray, and the thickness is 1cm;

(3) Drying the peach residue in step (2) with medium and short wave infrared, with a wavelength of 1.0-4.0 μm, a radiation power of 900 W, a drying temperature of 80° C., and a drying time of 4 hours.

(4) During the medium and short wave infrared drying process described in step (3), the humidity exhaust fan is turned on, and the wind speed is controlled to be 2.1m/s.

(5) The moisture content of the dried peach skin dregs obtained through the above steps is 7.36%, and the water activity is 0.53.

Example 2

Medium and short wave infrared fast drying apple pomace

Dry the apple pomace as follows:

(1) Apple (the kind is Shaanxi Qinguan) obtains apple pomace after belt pressing, and the moisture content is 76%;

(2) spread the apple pomace obtained in step (1) on the mesh tray, and the thickness is 1cm;

(3) Drying the apple pomace in step (2) with medium and short wave infrared, the wavelength is 1.0-4.0 μm, the radiation power is 1350W, the drying temperature is 70°C, and the drying time is 4.5h;

(4) During the medium and short wave infrared drying process described in step (3), the humidity exhaust fan is turned on, and the wind speed is controlled to be 2.1m/s.

(5) The moisture content of the dried apple pomace obtained through the above steps is 8.37%, and the water activity is 0.56.

Example 3

Short and medium wave infrared rapid drying of citrus pomace

Dry the citrus pomace as follows:

(1) citrus (the variety is Sanxia tangerine) is screw squeezed to obtain citrus peel residue with a water content of 80%;

(2) spread the apple pomace obtained in step (1) on the mesh tray, and the thickness is 1cm;

(3) Drying the apple pomace in step (2) with medium and short wave infrared, with a wavelength of 1.0-4.0 μm, a radiation power of 1350 W, a drying temperature of 80° C., and a drying time of 4.2 hours.

(4) During the medium and short wave infrared drying process described in step (3), the humidity exhaust fan is turned on, and the wind speed is controlled to be 2.1m/s.

(5) The moisture content of the dried apple pomace obtained through the above steps is 9.89, and the water activity is 0.59.

Example 4

Medium and Short Wave Infrared Rapid Drying of Pear Dregs

Dry pear pomace as follows:

(1) pears (the kind is Sanxia tangerine) obtain pear skin dregs after screwing the juice, and the moisture content is 75%;

(2) spread the apple pomace obtained in step (1) on the mesh tray, and the thickness is 0.5cm;

(3) Drying the pear pomace in step (2) with medium and short-wave infrared, with a wavelength of 1.0 μm, a radiation power of 1150 W, a drying temperature of 75° C., and a drying time of 5 hours.

(4) During the medium and short wave infrared drying process described in step (3), the humidity exhaust fan is turned on, and the wind speed is controlled to be 2m/s.

(5) The moisture content of the dried pear residue obtained through the above steps is 9.01%, and the water activity is 0.53.

Example 5

Medium and Short Wave Infrared Rapid Drying of Grape Pomace

Dry the pomace as follows:

(1) Grape pomace is obtained after the grapes are squeezed by a screw, and the water content is 80%;

(2) spread the apple pomace obtained in step (1) on the mesh tray, and the thickness is 0.75cm;

(3) Drying the apple pomace in step (2) by medium and short wave infrared, with a wavelength of 4.0 μm, a radiation power of 1200 W, a drying temperature of 73° C., and a drying time of 4.3 hours.

(4) During the medium and short wave infrared drying process described in step (3), the humidity exhaust fan is turned on, and the wind speed is controlled to be 3m/s.

(5) The moisture content of the dried apple pomace obtained through the above steps is 7.69, and the water activity is 0.57.

Example 6

Dry tomato pomace as follows:

(1) Tomato pomace is obtained after screw pressing, with a moisture content of 80%;

(2) spread the tomato skin residue obtained in step (1) on the mesh tray, and the thickness is 0.8cm;

(3) Drying the tomato pomace in step (2) by medium-short wave infrared, with a wavelength of 2.0 μm, a radiation power of 1000 W, a drying temperature of 73° C., and a drying time of 4.6 hours.

(4) During the medium and short wave infrared drying process described in step (3), the humidity exhaust fan is turned on, and the wind speed is controlled to be 2.5m/s.

(5) The moisture content of the dried tomato skin dregs obtained through the above steps is 8.63%, and the water activity is 0.57.

Example 7

Dry tomato pomace as follows:

(1) Tomato pomace is obtained after screw pressing, with a moisture content of 80%;

(2) spread the tomato skin residue obtained in step (1) on the mesh tray, and the thickness is 0.8cm;

(3) Drying the tomato pomace in step (2) by medium-short wave infrared, with a wavelength of 2.0 μm, a radiation power of 1000 W, a drying temperature of 73° C., and a drying time of 4.6 hours.

(4) During the medium and short wave infrared drying process described in step (3), the humidity exhaust fan is turned on, and the wind speed is controlled to be 2.5m/s.

(5) Using medium-wave infrared radiation with a wavelength of 2 μm and a radiation power of 1000 to irradiate pomace, the radiation distance is 10 cm, the temperature is 60 ° C, the irradiation time is 10 min, and the thickness of the pomace is 1 to 3 cm;

(6) Using short-wave infrared radiation with a wavelength of 0.7 μm and a radiation power of 1200 W to irradiate pomace, the radiation distance is 12 cm, the temperature is 50 ° C, the irradiation time is 5 min, and the thickness of the pomace is 2 cm.

The moisture content of the dried tomato skin dregs processed through the above steps is 8.03%, the water activity is 0.50, and the carotene content is increased by more than 10%.

Example 8

Dry carrot peels as follows:

(1) Carrot skin dregs are obtained after the carrot is squeezed by a screw, and the water content is 78%;

(2) spread the carrot peel dregs obtained in step (1) on the mesh tray, and the thickness is 1cm;

(3) Drying the carrot peel residue in step (2) with medium and short-wave infrared, with a wavelength of 3.0 μm, a radiation power of 1100 W, a drying temperature of 78° C., and a drying time of 4.8 hours.

(4) During the medium and short wave infrared drying process described in step (3), the humidity exhaust fan is turned on, and the wind speed is controlled to be 2.8m/s.

(5) Using medium-wave infrared radiation with a wavelength of 3 μm and a radiation power of 1250 W to irradiate carrot peels, the radiation distance is 15 cm, the temperature is 70 ° C, the irradiation time is 20 minutes, and the thickness of the laid fruit residues is 3 cm;

(6) Use short-wave infrared radiation with a wavelength of 1 μm and a radiation power of 1350 W to irradiate carrot pomace. The radiation distance is 15 cm, the temperature is 60 ° C, the irradiation time is 15 min, and the thickness of the pomace is 5 cm.

The moisture content of the dried tomato skin dregs processed through the above steps is 8.16%, the water activity is 0.49, and the carotene content is increased by more than 12%.

Example 9

Dry the pomace as follows:

(1) Grape pomace is obtained after the grapes are squeezed by a screw, and the water content is 80%;

(2) spread the grape pomace obtained in step (1) on the mesh tray, and the thickness is 0.8cm;

(3) Drying the grape pomace in step (2) by medium-short wave infrared with a wavelength of 2.0 μm, a radiation power of 1000 W, a drying temperature of 73° C., and a drying time of 4.6 hours.

(4) During the medium and short wave infrared drying process described in step (3), the humidity exhaust fan is turned on, and the wind speed is controlled to be 2.5m/s.

(5) Using medium-wave infrared radiation with a wavelength of 2.5 μm and a radiation power of 1125 W to irradiate grape pomace, the radiation distance is 12.5 cm, the temperature is 65 ° C, the irradiation time is 15 min, and the thickness of the grape pomace laid is 2 cm;

(6) Using short-wave infrared radiation with a wavelength of 0.85 μm and a radiation power of 1275 W to irradiate grape pomace, the radiation distance is 12.5 cm, the temperature is 55 ° C, the irradiation time is 10 min, and the thickness of the grape pomace is 3.5 cm.

The moisture content of the dried tomato skin dregs processed through the above steps is 7.43%, the water activity is 0.49, and the flavonol content is increased by more than 11%.

As mentioned above, the final water content of pomace dried by the method provided by the present invention is controlled below 10%, and the water activity is low, which is not conducive to the growth and reproduction of microorganisms, and can be stored for a long time. Use is guaranteed.

Although the embodiment of the present invention has been disclosed as above, it is not limited to the use listed in the specification and implementation, it can be applied to various fields suitable for the present invention, and it can be easily understood by those skilled in the art Therefore, the invention is not limited to the specific details and embodiments shown and described herein without departing from the general concept defined by the claims and their equivalents.

Claims (7)

1. a kind of infrared method for carrying out pomace drying of utilization intermediate waves, it is characterised in that include：

It is 1-4 μm using wavelength, radiant power carries out first stage process for the intermediate waves infrared radiation pomace of 900-1350W, Wherein, radiation length is 8-12cm, and temperature is 70-80 DEG C, and exposure time is 4-5h.

2. the infrared method for carrying out pomace drying of utilization intermediate waves as claimed in claim 1, it is characterised in that carry out the first rank When section is processed, the pomace is laid on drying frame, pomace thickness is 0.5～1.5cm.

3. the infrared method for carrying out pomace drying of utilization intermediate waves as claimed in claim 1, it is characterised in that first rank During section is processed, also include hydrofuge process, wet-emitting blower wind speed is 2-3m/s.

4. the infrared method for carrying out pomace drying of utilization intermediate waves as claimed in claim 1, it is characterised in that pomace to be dried Water content be 75～85%.

5. the infrared method for carrying out pomace drying of utilization intermediate waves as claimed in claim 1, it is characterised in that the pomace is From screw press, belt squeezing, spiral remaining pomace after squeezing the juice.

6. the infrared method for carrying out pomace drying of utilization intermediate waves as claimed in claim 1, it is characterised in that the pomace is In apple peel, peach skin slag, citrus peel residue, pear skin slag, grape skin, tomato peel and carrot skin slag any one or several Kind.

7. the infrared method for carrying out pomace drying of utilization intermediate waves as claimed in claim 1, it is characterised in that described first Also include carrying out after phase process successively：

Second stage process：It is 2-3 μm using wavelength, medium-wave infrared irradiation pomace of the radiant power for 1000-1250W, radiation Distance is 10-15cm, and temperature is 60-70 DEG C, and exposure time is 10-20min, and the pomace thickness of laying is 1～3cm；

Phase III is processed：It is 0.7-1 μm using wavelength, short-wave infrared radiation pomace of the radiant power for 1200-1350W, spoke Distance is penetrated for 12-15cm, temperature is 50-60 DEG C, exposure time is 5-15min, and the pomace thickness of laying is 2～5cm.