CN102669396A

CN102669396A - Cold air drying method for dried fruit

Info

Publication number: CN102669396A
Application number: CN2012101692496A
Authority: CN
Inventors: 满桂富; 李日坤; 宁进辉; 许英本
Original assignee: HEPU PERFUMING GARDEN FOOD CO Ltd
Current assignee: HEPU PERFUMING GARDEN FOOD CO Ltd
Priority date: 2012-05-28
Filing date: 2012-05-28
Publication date: 2012-09-19

Abstract

The invention discloses a cold air drying method for a dried fruit. The existing drying method includes heat drying, freeze drying, vacuum drying, infrared drying and the like, and the heat drying or freeze drying method is commonly used. The fruit contains glucose, fructose, sucrose, cellulose, vitamin, pigmentum, enzyme, water substance and protein which are all sensitive to temperature, and if the temperature is low, the dried fruit product becomes hard and is bad in taste; if the temperature is overhigh, the active ingredients in the fruit can be broken, and the dried fruit changes color and taste and looses the flavor. The common actions of an air conditioner, a fan and a dehumidifying device are utilized, the drying is conducted at the temperature lower than or equal to 37 DEG C, the temperature in the whole drying process is similar to room temperature in the southern region in China, so that the active ingredients contained in the fruit are not damaged, and the flavor of the fruit is maintained.

Description

A kind of method for cold air drying of fruit preserved fruit

Technical field

What the present invention relates to is a kind of method for cold air drying of fruit preserved fruit, belongs to fruit deep process technology field.

Background technology

China's south fruit generally has the maturity period to concentrate, and fruit is concentrated ripe phenomenon in a large number, and the fruit shelf life is all shorter, is not under the situation of very maturation at preservation technique, is prepared into preserved fruit to fruit, a kind of good method that improves the fruit added value of can yet be regarded as.As everyone knows; The preparation of fruit preserved fruit; Key technology is dry, and dry mass directly influences the quality of preserved fruit, because the water content of the quality of preserved fruit and preserved fruit, appearance luster, mouthfeel, local flavor, hygiene index, quality all have relation; Therefore, production is vital to the drying means of fruit preserved fruit for preserved fruit.Existing drying means, nothing more than heat drying, freeze drying, vacuum drying, infrared drying or the like, heat drying are in the dry preserved fruit of need, to import thermal source, make moisture in the fruit to external diffusion through improving temperature.Freeze drying is that the temperature of fruit is reduced, and when arriving certain low temperature, improves temperature again and makes water sublimed.Vacuum drying is the vacuum that reduces fruit, makes the moisture in the fruit more be prone to diffusion.Though these methods all have certain drying effect, yet the characteristic of fruit has determined these methods all to be not suitable for the production of preserved fruit.All contain glucose, fructose, sucrose, cellulose, vitamin, pigment, enzyme, moisture and protein in the fruit; Each fruit also has its specific composition; So the local flavor of particular fruit is just arranged; These compositions are very sensitive to temperature, and temperature is low can to cause the quality of preserved fruit product to harden, the mouthfeel variation; Temperature is too high, can destroy the effective ingredient of fruit the inside, makes the preserved fruit variable color spoiled, and local flavor loses to the greatest extent.Therefore seek the dry Perfected process of a kind of suitable fruit preserved fruit, be very important,, do not find to have the bibliographical information of desirable preserved fruit drying means through retrieval.

Summary of the invention

The method for cold air drying that the purpose of this invention is to provide a kind of fruit preserved fruit, overcome the traditional drying method can not rational and effective the deficiency of dry fruit, through the wood invention, can improve the comprehensive quality of preserved fruit, make the preserved fruit quality step higher level.

For realizing above-mentioned purpose, the present invention has taked following technical scheme, and a kind of method for cold air drying of fruit preserved fruit comprises following concrete steps:

1. fruit is carried out preliminary treatment, fruit is cleaned, need the removing skin of peeling; Be cut into sheet or bulk or strip, blanching 10-30 second in boiling water, place the high concentration liquid glucose dipping of sugar content 68-72% to make the chankings sugar content reach 33-36%; And make chankings hygiene index reach satisfactory standard; With 50-60 ℃ of heated-air drying 6-8 hour, make chankings reach moisture 30-35%, it is subsequent use to obtain the preserved fruit piece;

2. get the preserved fruit piece and be tiled on the tray, thickness is no more than 10 millimeters, and the tray that will be paved with the preserved fruit piece to put into drying device dry;

3. in drying device, start blower fan the air in the drying device is flowed, gas flow rate is the 1.0-1.5 meter per second; Start dehumidifier and air-conditioning simultaneously; Dehumidifier can heat release in dehumidifying, and this moment, air-conditioning made the gas temperature in the hothouse be in 30-35 ℃ to gas refrigeration, every cubic metre of volume moisture removal reach the 0.06-0.08 liter/hour; Dry 10-12 hour like this, obtaining water content was the fruit preserved fruit of 10-20%.

Take the present invention of above-mentioned measure, when dry preserved fruit, utilize the acting in conjunction of air-conditioning, blower fan and dehydrating unit; Be no more than under 37 ℃ the state dryly in temperature, whole dry run temperature is similar with China southern area room temperature, and effective ingredient contained in the fruit is not had any destruction; Kept original vitamin in the fruit to greatest extent, cellulose, enzyme; Protein and other are of value to the composition of human body, and preserved fruit has kept the peculiar taste of former fruit, and preserved fruit quality soft or hard is suitable; Surface color is bright and new tempting, and preserved fruit has reached following technical indicator:

Project	Standard value
		Color and luster	The basic primary colors that keeps
Tissue morphology	Complete form, basically identical
		Smell	Has distinctive flavour of corresponding kind fruit and fragrance, free from extraneous odour
Impurity	There is not macroscopic exogenous impurity
		Moisture content %	≤20.0
Moisture activity	≤0.65

Total plate count (CFU/g)	≤1000
		Coliform (MPN/100g)	≤30
Mould (CFU/g)	≤50
		. saccharomycete (CFU/g)	/
Pathogenic bacteria	Must not detect

The specific embodiment

Embodiment 1

1. get pineapple and peel, clean, be cut into bulk; Blanching is 20 seconds in boiling water; Place the high concentration liquid glucose dipping of sugar content 70% to make the chankings sugar content reach 35%, and make chankings hygiene index reach satisfactory standard, with 50-60 ℃ of heated-air drying 8 hours; Make chankings reach moisture 30-35%, it is subsequent use to obtain the preserved fruit piece;

2. get the pineapple piece and be tiled on the tray, thickness is no more than 10 millimeters, and the tray that will be paved with the pineapple piece to put into volume through drying frame be that the drying device of 180-200 cubic meter is dry;

3. in drying device, start two power and be 0.37 kilowatt blower fan, make air quantity reach 28000 cubic metres/hour; Air in the drying device is flowed, and gas flow rate is the 1.0-1.5 meter per second, starts two dehumidifiers, two air-conditionings simultaneously; The air themperature balance is to 30-35 degree centigrade; The moisture removal of every dehumidifier reaches 6.8 liters/hour, dry 10-12 like this hour, obtains water content and be 15% pineapple preserved fruit.

Embodiment 2

1. get mango and clean stoning; Be cut into bulk, blanching is 15 seconds in boiling water, places the high concentration liquid glucose dipping of sugar content 70% to make the chankings sugar content reach 35%; And make chankings hygiene index reach satisfactory standard; With 50-60 ℃ of heated-air drying 8 hours, make chankings reach moisture 30-35%, it is subsequent use to obtain the preserved fruit piece;

2. get the mango piece and be tiled on the tray, thickness is no more than 10 millimeters, and the tray that will be paved with the mango piece to put into volume through drying frame be that the drying device of 180-200 cubic meter is dry;

3. in drying device, start two power and be 0.37 kilowatt blower fan, make air quantity reach 28000 cubic metres/hour; Air in the drying device is flowed, and gas flow rate is the 1.0-1.5 meter per second, starts two dehumidifiers, two air-conditionings simultaneously; Air themperature balance and 30-35 degree centigrade; The moisture removal of every dehumidifier reaches 6.8 liters/hour, and dry 10-12 like this hour, obtaining water content was the mango preserved fruit of 10-20%.

Embodiment 3

1. getting the holy girl really cleans; Remove the base of a fruit, blanching 10-30 second in boiling water, place the high concentration liquid glucose dipping of sugar content 68-72% to make the chankings sugar content reach 33-36%; And make chankings hygiene index reach satisfactory standard; With 50-60 ℃ of heated-air drying 6-8 hour, make chankings reach moisture 30-35%, it is subsequent use to obtain the preserved fruit piece;

2. get the holy girl and really be tiled on the tray, only spread one deck, and the tray that will be paved with the pineapple piece to put into volume through drying frame be that the drying device of 180-200 cubic meter is dry;

3. in drying device, start two power and be 0.37 kilowatt blower fan, make air quantity reach 28000 cubic metres/hour; Air in the drying device is flowed, and gas flow rate is the 1.0-1.5 meter per second, starts two dehumidifiers, two air-conditionings simultaneously; Air themperature balance and 30-35 degree centigrade; The moisture removal of every dehumidifier reaches 6.8 liters/hour, and dry 10-12 like this hour, obtaining water content was the holy girl fruit preserved fruit of 10-20%.

Claims

1. the method for cold air drying of a fruit preserved fruit is characterized in that said method comprises following concrete steps:

(1) fruit is carried out preliminary treatment, fruit is cleaned, need the removing skin of peeling; Be cut into sheet or bulk or strip, blanching 10-30 second in boiling water, place the high concentration liquid glucose dipping of sugar content 68-72% to make the chankings sugar content reach 33-36%; And make chankings hygiene index reach satisfactory standard; With 50-60 ℃ of heated-air drying 6-8 hour, make chankings reach moisture 30-35%, it is subsequent use to obtain the preserved fruit piece;

(2) get the preserved fruit piece and be tiled on the tray, thickness is no more than 10 millimeters, and the tray that will be paved with the preserved fruit piece to put into drying device dry;

(3) in drying device, start blower fan the air in the drying device is flowed, gas flow rate is the 1.0-1.5 meter per second; Start dehumidifier and air-conditioning simultaneously; Dehumidifier can heat release in dehumidifying, and this moment, air-conditioning made the gas temperature in the hothouse be in 30-35 ℃ to gas refrigeration, every cubic metre of volume moisture removal reach the 0.06-0.08 liter/hour; Dry 10-12 hour like this, obtaining water content was the fruit preserved fruit of 10-20%.