阅读说明：本技术 一种肉类抗菌防腐保鲜膜、保鲜袋及其制备方法 (Meat antibacterial and antiseptic preservative film, preservative bag and preparation method thereof ) 是由 李丹 李中华 王鑫 张富丽 侯建设 王学晖 张佳佳 张春红 李哲 于 2020-05-27 设计创作，主要内容包括：本发明属于食品包装技术领域,提供了一种肉类抗菌防腐保鲜膜,它包括依次压合形成的以下层结构：第一聚乙烯层、第一醋酸乙烯酯共聚物层、聚偏二氯乙烯层、第二醋酸乙烯酯共聚物层、第二聚乙烯层、聚丁二烯1,3-丁二烯的聚合物层；其中所述第一聚乙烯层中包括占第一聚乙烯层重量百分比2-6％的纳米银聚乙烯抗菌母粒和占第一聚乙烯层重量百分比1％的开口爽滑剂；制成保鲜袋时,所述第一聚乙烯层设置在保鲜袋内侧,与待保鲜物接触。本发明的肉类抗菌防腐保鲜袋能显著延长鲜肉类的保鲜时间。(The invention belongs to the technical field of food packaging, and provides an antibacterial and antiseptic meat preservative film which comprises the following layers of structures formed by sequential pressing: a first polyethylene layer, a first vinyl acetate copolymer layer, a polyvinylidene chloride layer, a second vinyl acetate copolymer layer, a second polyethylene layer, and a polymer layer of polybutadiene 1, 3-butadiene; wherein the first polyethylene layer comprises nano-silver polyethylene antibacterial master batches accounting for 2-6 wt% of the first polyethylene layer and an opening slipping agent accounting for 1 wt% of the first polyethylene layer; when making the freshness protection package, first polyethylene layer sets up at the freshness protection package inboard, with treat the freshness protection package contact. The antibacterial and antiseptic meat freshness protection package can obviously prolong the freshness protection time of fresh meat.)

1. The antibacterial and antiseptic meat preservative film is characterized by comprising the following five-layer structure formed by sequentially pressing: the polyethylene film comprises a first polyethylene layer, a first vinyl acetate copolymer layer, a polyvinylidene chloride layer, a second vinyl acetate copolymer layer and a second polyethylene layer;

wherein the first polyethylene layer comprises nano-silver polyethylene antibacterial master batches accounting for 2-6 wt% of the first polyethylene layer and an opening slipping agent accounting for 1 wt% of the first polyethylene layer;

the melt index of the nano-silver polyethylene antibacterial master batch is less than or equal to 10g/10 min.

2. The meat antiseptic, preservative and preservative film of claim 1 further comprising a polymer layer of polybutadiene 1, 3-butadiene, said polymer layer of polybutadiene 1, 3-butadiene being disposed on a side of said second polyethylene layer distal from said second vinyl acetate copolymer layer.

3. The antibacterial preservative film for meat as claimed in claim 2, wherein the structures of the layers account for the following mass percent of the preservative bag:

first and second polyethylene layers: 40-50%;

first and second vinyl acetate copolymer layers: 30% -40%;

polyvinylidene chloride layer: 12 to 15 percent;

polymer layer of polybutadiene 1, 3-butadiene: 5 to 10 percent.

4. The meat antibacterial preservative film according to claim 2, wherein the thickness of the film is in the range of 45-65 μm;

the longitudinal tensile strength of the antibacterial preservative film for meat is more than 35Mpa, and the transverse tensile strength of the antibacterial preservative film for meat is more than 35 Mpa; the longitudinal elongation at break is more than or equal to 50 percent, and the transverse elongation at break is more than or equal to 50 percent; the moisture permeability under the conditions of 38 ℃ and 100 percent relative humidity is not more than 10 g/square meter per 24 h.atm; the oxygen permeability under the conditions of 38 ℃ and 100 percent relative humidity is not more than 20 cc/square meter.24 h.atm.

5. An antibacterial and antiseptic meat freshness protection package is characterized in that the freshness protection package is made of the freshness protection film of any one of claims 1 to 4, the first polyethylene layer is arranged on the inner side and serves as an inner layer of the antibacterial and antiseptic meat freshness protection package, and when the freshness protection package is used for containing articles, the freshness protection package is in direct contact with the articles to be preserved.

6. A method for preparing the antibacterial preservative film for meat as claimed in claim 5 comprises the following steps: the method is characterized by comprising the following steps:

s1, preparing polyethylene, vinyl acetate copolymer and polyvinylidene chloride, and dividing the polyethylene and the vinyl acetate copolymer into two parts according to the designed layer thickness or weight;

s2, adding the nano-silver polyethylene antibacterial master batch and the opening slipping agent into one part of polyethylene, and uniformly mixing to form a polyethylene mixture;

s3, placing the raw materials in the steps S1 and S2 in different hoppers of a film blowing machine according to the sequence of polyethylene, vinyl acetate copolymer, polyvinylidene chloride, vinyl acetate copolymer and polyethylene mixture from outside to inside, and forming a five-layer cylindrical film through melting, co-extrusion and film blowing;

s4, placing the five-layer cylindrical film for 48 hours for crosslinking, and obtaining the antibacterial and antiseptic meat freshness protection package through a bag making process of a bag making machine.

7. The method of claim 6, wherein the step S1 further comprises preparing a polybutadiene 1, 3-butadiene polymer, which is placed in the outermost hopper in the step S2;

the blow-up ratio in the raw material blown film process in step S3: the stretching ratio is (3-4):1, and the environment temperature of the film blowing is 15-17 ℃.

8. The method for preparing the antibacterial, antiseptic and freshness-keeping bag for meat according to claim 7,

the melt indexes of the polymers of the polyethylene, the vinyl acetate copolymer, the polyvinylidene chloride and the polybutadiene 1, 3-butadiene are all less than or equal to 10g/10 min.

9. The method for preparing the antibacterial, antiseptic and freshness-keeping meat bag according to claim 7, wherein the formula formed by the polymer mass of the polyethylene, the vinyl acetate copolymer, the polyvinylidene chloride and the polybutadiene 1, 3-butadiene accounting for the total mass of the raw materials is one of the following three formulas:

the formula I is as follows: a polymer of 40% polyethylene + 40% vinyl acetate copolymer + 12% polyvinylidene chloride + 8% polybutadiene 1, 3-butadiene;

and a second formula: a polymer of 45% polyethylene + 30% vinyl acetate copolymer + 15% polyvinylidene chloride + 10% polybutadiene 1, 3-butadiene;

and the formula III: a polymer of 43% polyethylene + 38% vinyl acetate copolymer + 14% polyvinylidene chloride + 5% polybutadiene 1, 3-butadiene.

Technical Field

The invention relates to the technical field of food packaging, in particular to an antibacterial and antiseptic meat preservative film, a preservative bag and a preparation method thereof.

Background

At present, with the continuous improvement of living standard of people, the quality requirements of people on vegetables, fruits, meat and the like are higher and higher, meanwhile, the loss of the vegetables, the fruits and the meat in daily life is also huge, the meat is stored at a higher loss rate, and the enhancement of the preservation of the meat, the vegetables and the fruits is particularly necessary.

At present, the meat preservation technology is researched more, and the technology mainly comprises an active packaging preservation technology, modified atmosphere preservation, ultrahigh pressure preservation, ice temperature preservation, biological preservative preservation and the like. In the aspect of the use and application of the preservative film, the most applied method is to achieve the preservation of packaged meat by adding an antibacterial active agent and the like into a high polymer preservative material, such as: adding the antibacterial substance into an extruder, mixing the antibacterial substance into a preservative film or coating the antibacterial substance on the layer surface of the multilayer packaging material contacted with food to achieve the aim of preserving the meat; the aim of keeping the meat fresh is also achieved by physically radiating and chemically modifying the packaging material.

Disclosure of Invention

The invention aims to provide an antibacterial and antiseptic meat preservative film which is formed by taking various polymers of different types as main materials, adding a nano silver material with antibacterial property and an opening slipping agent, can realize antibacterial and good preservation property when being used as a preservative bag, obviously prolongs the preservation time period of fresh meat, enhances the meat preservation and solves the waste problem.

The technical scheme of the invention is that the meat antibacterial and antiseptic preservative film comprises the following five-layer structure formed by sequential pressing: the polyethylene film comprises a first polyethylene layer, a first vinyl acetate copolymer layer, a polyvinylidene chloride layer, a second vinyl acetate copolymer layer and a second polyethylene layer; wherein the first polyethylene layer comprises nano-silver polyethylene antibacterial master batches accounting for 2-6 wt% of the first polyethylene layer and an opening slipping agent accounting for 1 wt% of the first polyethylene layer; the melt index of the nano-silver polyethylene antibacterial master batch is less than or equal to 10g/10 min.

The meat needs to be kept fresh as far as possible to block air (oxygen), and polyvinylidene chloride (PVDC) is a chemical material with good barrier property and without being influenced by humidity, is a good barrier material, but cannot be directly fused with Polyethylene (PE). It is desirable that the intermediate-first vinyl acetate copolymer layer (EVA) fuse polyvinylidene chloride with PE, with PE in the inner and outermost layers and polyvinylidene chloride as the middle layer.

Further, the preservative film also comprises a polymer layer of polybutadiene 1, 3-butadiene, wherein the polymer layer of polybutadiene 1, 3-butadiene is arranged on the side, far away from the second vinyl acetate copolymer layer, of the second polyethylene layer.

Further, each layer structure accounts for the following mass percent of the freshness protection package:

first and second polyethylene layers: 40-50%;

first and second vinyl acetate copolymer layers: 30% -40%;

polyvinylidene chloride layer: 12 to 15 percent;

polymer layer of polybutadiene 1, 3-butadiene: 5 to 10 percent.

Further, the thickness of the preservative film is within the range of 45-65 μm; the longitudinal tensile strength of the antibacterial preservative film for meat is more than 35Mpa, and the transverse tensile strength of the antibacterial preservative film for meat is more than 35 Mpa; the longitudinal elongation at break is more than or equal to 50 percent, and the transverse elongation at break is more than or equal to 50 percent; the moisture permeability under the conditions of 38 ℃ and 100 percent relative humidity is not more than 10 g/square meter per 24 h.atm; the oxygen permeability under the conditions of 38 ℃ and 100 percent relative humidity is not more than 20 cc/square meter.24 h.atm.

The invention also provides an antibacterial and antiseptic meat preservative bag which is made of the antibacterial and antiseptic meat preservative film, wherein the first polyethylene layer is arranged at the inner side and is used as the inner layer of the preservative bag, and the antibacterial and antiseptic meat preservative bag is in direct contact with an object to be preserved when containing objects.

The invention also provides a preparation method of the antibacterial and antiseptic meat preservative film, which comprises the following steps: the method comprises the following steps:

s1, preparing polyethylene, vinyl acetate copolymer and polyvinylidene chloride, and dividing the polyethylene and the vinyl acetate copolymer into two parts according to the designed layer thickness or weight;

s2, adding the nano-silver polyethylene antibacterial master batch and the opening slipping agent into one part of polyethylene, and uniformly mixing to form a polyethylene mixture;

s3, placing the raw materials in the steps S1 and S2 in different hoppers of a film blowing machine according to the sequence of polyethylene, vinyl acetate copolymer, polyvinylidene chloride, vinyl acetate copolymer and polyethylene mixture from outside to inside, and carrying out melting, co-extrusion and film blowing to form a five-layer cylindrical film;

s4, placing the five layers of cylindrical films for 48 hours for crosslinking, and obtaining the antibacterial and antiseptic meat freshness protection package through a bag making process of a bag making machine.

Further, the above step S1 includes preparing a polymer of polybutadiene 1, 3-butadiene, which is disposed in the outermost hopper in step S2;

the blow-up ratio in the raw material blown film process in step S3: the stretching ratio is (3-4):1, and the environment temperature of the film blowing is 15-17 ℃.

Furthermore, the melt indexes of the polymers of the polyethylene, the vinyl acetate copolymer, the polyvinylidene chloride and the polybutadiene 1, 3-butadiene are all less than or equal to 10g/10 min.

Further, the formula formed by the polymer mass of the polyethylene, the vinyl acetate copolymer, the polyvinylidene chloride and the polybutadiene 1, 3-butadiene accounting for the total mass of the raw materials is selected from one of the following three formulas:

the formula I is as follows: a polymer of 40% polyethylene + 40% vinyl acetate copolymer + 12% polyvinylidene chloride + 8% polybutadiene 1, 3-butadiene;

and a second formula: a polymer of 45% polyethylene + 30% vinyl acetate copolymer + 15% polyvinylidene chloride + 10% polybutadiene 1, 3-butadiene;

and the formula III: a polymer of 43% polyethylene + 38% vinyl acetate copolymer + 14% polyvinylidene chloride + 5% polybutadiene 1, 3-butadiene.

The meat antibacterial and antiseptic preservative bag is used for preserving meat, the preservation time of the meat can be greatly prolonged, fresh pork can be preserved for 25 days, and beef can be preserved for 90 days.

Detailed Description

The present invention will be described in further detail below with reference to specific embodiments in order to make the present invention better understood by those skilled in the art.