CN105660825A

CN105660825A - Worm-prevention fresh keeping method of no-clean red jujubes

Info

Publication number: CN105660825A
Application number: CN201511034610.4A
Authority: CN
Inventors: 焦中高; 刘杰超; 张春岭; 陈大磊
Original assignee: Zhengzhou Fruit Research Institute CAAS
Current assignee: Zhengzhou Fruit Research Institute CAAS
Priority date: 2015-12-30
Filing date: 2015-12-30
Publication date: 2016-06-15
Anticipated expiration: 2035-12-30
Also published as: CN105660825B

Abstract

The invention discloses a worm-prevention fresh keeping method of no-clean red jujubes. The method comprises the following steps of firstly killing potential worm ova and young worms in raw materials of red jujubes by a freeze-thaw processing method, and then performing fresh keeping treatment by a modified atmosphere packaging manner during packaging, so that the worm-prevention fresh keeping purpose of the no-clean red jujubes is achieved by a purely physical method when the freeze-thaw processing method is combined with the modified atmosphere packaging manner. According to the worm-prevention fresh keeping method disclosed by the invention, the technology is simple, no chemical agents are used, the problems that worms are generated, the red jujubes mildew and rot, pulp has brown stains, nutrient losses are caused and the colors become bad in the storage and sale process of the no-clean red jujubes can be effectively solved, and the worm-prevention fresh keeping method is particularly suitable for fresh keeping of half-dried no-clean red jujubes with a certain moisture content.

Description

The insect protected fresh keeping method of a kind of wash-free red dates

Technical field

The present invention relates to red date fresh-keeping technical field, specifically the insect protected fresh keeping method of a kind of wash-free red dates.

Background technology

Red date is the traditional excellent tonic product of China, and its effect such as blood-enriching qi-invigorating, beautifying face and moistering lotion is pursued deeply, is therefore one of the important batching of China's traditional methods to keep in good health's meals always. Along with the development of society and the raising of living standards of the people, more and more human consumers pays close attention to the health of self more, and edible red date is one of good selection, but owing to traditional red date is without cleaning and sterilizing, edible inconvenient, therefore make wash-free red dates market comparatively fast be developed. More than the 80% of current China red date year amount of finish is wash-free red dates, and its market scale also constantly expands, and increases progressively with the ratio of annual more than 10% in recent years always. In order to keep good mouthfeel, wash-free red dates must keep certain moisture (generally 20～25%), cause its very easily occur in storage sales process infested, go mouldy, g, nutritive loss and color and luster deterioration etc., therefore must take certain technique means, wash-free red dates is carried out insect protected Preservation Treatment. Generally adopt chemical preservative fresh-keeping in wash-free red dates is processed at present, the method even also being taked chemical agent stifling in order to prevent to damage by worms kills worm's ovum potential in red date raw material and larva, bring certain potential safety hazard to product, also it is not consistent with present food security development trend and customer demand.

Summary of the invention

It is an object of the invention to provide a kind of green, safety, free of contamination wash-free red dates insect protected fresh keeping method.

For reaching foregoing invention object, the present invention adopts following technical scheme:

In the wash-free red dates course of processing, first adopting the method for freeze thawing treatment to kill worm's ovum potential in red date raw material and larva, then adopt when packing the mode of modified atmosphere packaging to carry out Preservation Treatment, the two combines and reaches the fresh-keeping object of pure physical method insect protected. Specifically comprise the following steps:

1) screening nothing is gone mouldy, the water content of free from insect pests is about 25～30% half dry-making red date, carton or plastic crate is loaded after classification, it is placed in-22～-25 DEG C of cryogenic freezing storehouses freezing 72～96 hours, then takes out, thaw under 20～25 DEG C of conditions 48～96 hours.

2) by existing technique, to step 1) red date that obtains cleans, dry, selected etc.

3) by step 2) featured red date loads in bag film, it is placed in and fills nitrogen Vacuum Packaging Machine, regulate the pumpdown time, fill the nitrogen time etc., make a nitrogen content being equipped with in the bag film of wash-free red dates be 90～98%, obtain modified atmosphere packaging wash-free red dates after heat-sealing, carry out storing or selling.

Step 1) in freeze thawing treatment need to repeatedly carry out freezing-thaw 2～4 times, with thorough killing ova.

Step 2) in the dry hot blast temperature adopted be 45～65 DEG C, after dry, red date moisture content is 20～25%.

Utilize method provided by the present invention that red date is carried out insect protected Preservation Treatment, the wash-free red dates prepared occurs without infested, mildew phenomena in selling period, the speed that g degree and total polyphenols, general flavone content decline significantly processes lower than blank and chemical preservative, reaches the object that insect protected is fresh-keeping. Technique of the present invention is simple, do not use any chemical agent, pure physical method is adopted to achieve the green non-pollution of wash-free red dates fresh-keeping, avoid the security risk using chemical preservative and pharmacy fumigation to kill worm and may bring, improve quality and the market competitiveness of wash-free red dates product, there is obvious Social benefit and economic benefit.

Embodiment

Below in conjunction with embodiment the present invention will be further explained explanation.

Embodiment 1

An insect protected fresh keeping method for wash-free red dates, comprises the following steps:

1) screening nothing is gone mouldy, the water content of free from insect pests is about 25～30% half dry-making red date, loads carton or plastic crate, be placed in-22～-25 DEG C of cryogenic freezing storehouses freezing 96 hours, then take out, thaw 72 hours under 20～25 DEG C of conditions after classification. Repeat said process 2 times.

2) the red date clean water after thawing, removes surface dirt etc., is then placed under the condition of 50 ± 5 DEG C, drying room inherence warm air drying, takes out, Temperature fall when being down to below 25% to moisture content, selected.

3) featured red date loads in bag film, it is placed in and fills nitrogen Vacuum Packaging Machine, regulate the pumpdown time, fill the nitrogen time etc., make a nitrogen content being equipped with in the bag film of wash-free red dates reach more than 90%, obtain modified atmosphere packaging wash-free red dates after heat-sealing, carry out storing or selling.

Embodiment 2

1) screening nothing is gone mouldy, the water content of free from insect pests is about 25～30% half dry-making red date, loads carton or plastic crate, be placed in-22～-25 DEG C of cryogenic freezing storehouses freezing 72 hours, then take out, thaw 48 hours under 20～25 DEG C of conditions after classification. Repeat said process 3 times.

2) the red date clean water after thawing, removes surface dirt etc., is then placed under the condition of 60 ± 5 DEG C, drying room inherence warm air drying, takes out, Temperature fall when being down to below 25% to moisture content, selected.

3) featured red date loads in bag film, it is placed in and fills nitrogen Vacuum Packaging Machine, regulate the pumpdown time, fill the nitrogen time etc., make a nitrogen content being equipped with in the bag film of wash-free red dates be about 95%, obtain modified atmosphere packaging wash-free red dates after heat-sealing, carry out storing or selling.

Embodiment 3

1) screening nothing is gone mouldy, half dry-making red date water content of free from insect pests is about 25～30% half dry-making red date, carton or plastic crate is loaded after classification, it is placed in-22～-25 DEG C of cryogenic freezing storehouses freezing 80 hours, then takes out, thaw under 20～25 DEG C of conditions 60 hours. Repeat said process 2 times.

2) the red date clean water after thawing, removes surface dirt etc., is then placed in drying room under 50～60 DEG C of conditions warm air drying, takes out, Temperature fall when being down to below 25% to moisture content, selected.

3) featured red date loads in bag film, it is placed in and fills nitrogen Vacuum Packaging Machine, regulate the pumpdown time, fill the nitrogen time etc., make a nitrogen content being equipped with in the bag film of wash-free red dates be 92～93%, obtain modified atmosphere packaging wash-free red dates after heat-sealing, carry out storing or selling.

Claims

1. the insect protected fresh keeping method of a wash-free red dates, it is characterised in that, comprise the following steps:

1) screening nothing is gone mouldy, the water content of free from insect pests is about 25～30% half dry-making red date, carton or plastic crate is loaded after classification, it is placed in-22～-25 DEG C of cryogenic freezing storehouses freezing 72～96 hours, then takes out, thaw under 20～25 DEG C of conditions 48～96 hours;

2) by existing technique, to step 1) red date that obtains cleans, dry, selected etc.;

2. the insect protected fresh keeping method of a kind of wash-free red dates according to claim 1, it is characterised in that: step 1) in freeze thawing treatment need to repeatedly carry out freezing-thaw 2～4 times, with thorough killing ova.

3. the insect protected fresh keeping method of a kind of wash-free red dates according to claim 1, it is characterised in that: step 2) in the dry hot blast temperature adopted be 45～65 DEG C, after dry, red date moisture content is 20～25%.