CN102050273A - Manufacturing method of packing material capable of sensing food freshness - Google Patents

Abstract

The invention discloses a method for manufacturing a packaging material capable of perceiving the freshness of food. First, different gas color-sensitive materials that have color changes in the odor emitted by the food deterioration are selected for different types of food; and then food-grade safety film or Acid-free paper is used as the base material for food packaging; finally, different gas color-sensitive materials are dissolved in corresponding organic solvents to form different gas color-sensitive material solutions with a concentration of 0.1-0.5mol/L, and then different gas color-sensitive materials A stabilizer with a concentration of 5 mol/L is added to the solution, and then the obtained different products are uniformly coated with a group of gas color-sensitive material dot arrays at intervals in the center of the food packaging base material by means of inkjet. Or a column of gas color sensitive material dots. The packaging material made by the invention not only has the fresh-keeping function of ordinary packaging materials, but also can sense the freshness and quality of food, and can also be used for anti-counterfeit packaging of medicine, cosmetics and chemical industry.

Description

A method of manufacturing a packaging material capable of sensing food freshness

technical field

The invention relates to a food packaging material, in particular to a manufacturing method of a packaging material capable of perceiving the freshness and quality of food.

Background technique

Most of the current food packaging materials are based on their shape, color and function. The function is mainly to improve the air permeability of the packaging material by adding rare metals to the material and through special processes such as nanometer and silicon windows, so as to prolong the shelf life of food. and shelf life. However, the quality of packaged food, especially fresh food, and whether it has deteriorated must be obtained through a series of physical and chemical analysis methods. At present, there is no packaging material that can perceive the freshness of food, so that consumers or quality inspectors can know the freshness of the food at a glance.

Volatile gases (VOCs) in food are mainly small organic molecules such as esters, aldehydes, alcohols, ketones, aromatic hydrocarbons, and organic acids. During the process of food deterioration, VOCs will change significantly, and microorganisms will also produce spoilage gases such as acids, alcohols, ammonia and amines. The quality and freshness of the food can be known through the gas emitted by the food. However, the current volatile gas detection in food is mainly gas chromatography and sensory evaluation, both of which are time-consuming and laborious, and require professionals to complete.

In 2000, Professor Kenneth S. Suslick of the University of Illinois at Urbana-Champaign discovered that some chemicals such as metalloporphyrins and pH indicators will change color when they encounter odor molecules. These chemicals are called gas color-sensitive materials, so These gas color-sensitive materials can be made into sensors to detect odors, which are called color-sensitive gas sensors. The color-sensitive gas sensor has the property of molecular recognition, can distinguish similar chemical substances, even isomers with very similar chemical properties, and is not sensitive to the temperature and humidity of the environment.

Contents of the invention

In order to overcome the deficiencies of the prior art, the present invention proposes a manufacturing method of a new type of packaging material, which combines gas color-sensitive materials with traditional food packaging materials, so that the produced packaging materials can directly sense the freshness and quality of food.

The technical scheme of the present invention adopts the following steps in sequence: first, for different types of food, select different gas color-sensitive materials that have color changes in the odor emitted by the food deterioration; then select food-grade safety film or acid-free paper as Food packaging base material; finally, different gas color-sensitive materials are dissolved in corresponding organic solvents to form different gas color-sensitive material solutions with a concentration of 0.1-0.5mol/L, and then added to different gas color-sensitive material solutions Stabilizer, the concentration of the stabilizer is 5mol/L, and then the obtained different products are uniformly coated in a group of gas at intervals of L=10-15cm in the center of the food packaging base material by means of inkjet. Color-sensitive material point array, the diameter of each gas color-sensitive material point is 1-5mm, drying each group of gas color-sensitive material point arrays can be made into a unified packaging material for various foods; or a certain product obtained At intervals of L=10-15cm in the center of the food packaging base material, use inkjet method to uniformly paint a gas color-sensitive material point with a diameter of 1-5mm at intervals, and all the gas color-sensitive material points form a row. , drying each gas color-sensitive material point to make a specific type of packaging material for a certain type of food.

The packaging material made by the invention not only has the freshness preservation function of ordinary packaging materials, but also can sense the freshness and quality of the packaged food, and can also be used for anti-counterfeiting packaging of medicine, cosmetics and chemical industry, and has broad application prospects.

Description of drawings

   Below in conjunction with accompanying drawing and 2 embodiments the present invention is described in further detail:

Fig. 1 is a schematic diagram of a unified packaging material in Example 1, and the food packaging base material is a plastic wrap;

Fig. 2 is a schematic diagram of a special-purpose packaging material in Example 1, and the food packaging base material is a plastic wrap;

Fig. 3 is the freshness and shelf life situation diagram of eggs under the normal temperature indicated by the color of the gas color-sensitive material of the unified plastic wrap;

Fig. 4 is the situation diagram of the freshness and shelf life of fish meat under normal temperature indicated by the color of the gas color-sensitive material of the special-purpose plastic wrap;

Fig. 5 is the color display diagram of the gas color-sensitive material of two kinds of commonly used perfumes in the market;

In the figure: 1. Preservative film; 2. Gas color-sensitive material points.

Example 1

There are mainly four types of food in daily life, namely eggs and milk, meat, fish and fruits and vegetables, each of which emits a different smell. There are two types of plastic wrap used for these foods. One is a special type of plastic wrap, which is specially used for a new type of freshness preservation of a certain type of food. Therefore, the specific type of plastic wrap is divided into egg and milk type plastic wrap, meat plastic wrap, Fish cling film and fruit and vegetable cling film. The other is a unified type of fresh-keeping film, which can be used as a new type of fresh-keeping for various foods. Among them, the odor component emitted by the corruption of eggs and milk is mainly hydrogen sulfide, so choose gas color-sensitive materials that have obvious changes in color when reacting with hydrogen sulfide, such as iron porphyrin, tin porphyrin, methylene blue, Nile red, fluorescent yellow, etc. The gas color-sensitive material of the new type of fresh-keeping film for eggs and milk; the odor component emitted by meat corruption is mainly ammonia odor, and the odor component emitted by fish corruption is mainly amine odor, choose iron porphyrin that has a color reaction with ammonia and amine Porphyrin, zinc porphyrin, tin porphyrin, cobalt porphyrin, silver porphyrin and pH indicators are used as gas color-sensitive materials for new plastic wraps for meat and fish; the odor components emitted by the spoilage of fruits and vegetables are mainly methyl mercaptan, Cobalt porphyrin, protoporphyrin, copper porphyrin and pH indicator were selected as gas color-sensitive materials for new plastic wraps for fruits and vegetables. The gas color-sensitive material of the unified plastic wrap includes each of the gas color-sensitive materials mentioned above.

Choose food-grade safety film, such as polyethylene, polyvinyl chloride and polyvinylidene chloride, as the food packaging base material. Each of the selected different gas color-sensitive materials is dissolved in a corresponding organic solvent, and the gas color-sensitive material is dissolved at a concentration of 0.1-0.5 mol/L to form different gas color-sensitive material solutions. The present invention selects different organic solvents for different gas color-sensitive materials, for example, selects chlorotoluene as the solvent for the porphyrin compound, and selects alcohol as the solvent for the hydrophobic acid-base indicator. Then add a stabilizer to different gas color-sensitive material solutions, the concentration of the stabilizer in different gas color-sensitive material solutions is 5mol/L, and the stabilizer can be dibutyl phthalate.

As shown in Figure 1, the different products obtained above, that is, different gas color-sensitive material solutions added with stabilizers, are respectively sprayed on the plastic wrap 1 at intervals and evenly by point spraying, forming a group of gas color-sensitive materials. permutation array. Spray a group of such gas color-sensitive material arrays at intervals of L=10-15cm in the center of the plastic wrap. The diameter of each gas color-sensitive material point 2 in the array is 1-5mm, and then quickly use hot air to Each gas color-sensitive material point 2 in each group of gas color-sensitive material point arrays is dried to obtain the required unified plastic wrap for various food packaging.

As shown in Figure 2, the production of special-purpose plastic wrap is relatively simple. It is only necessary to select one of the gas color-sensitive materials that have obvious color changes to the smell of this type of food and dissolve it in an organic solvent at a concentration of 0.1-0.5mol/L. , then add a stabilizer with a concentration of 5mol/L, and apply the resulting product on the preservative film 1 at intervals and evenly by point spraying, and spray a Gas color-sensitive material dots 2 with a diameter of 1-5mm form a row of all gas color-sensitive material dots 2, and then quickly dry each gas color-sensitive material dot 2 in the row with hot air to obtain the desired A specific type of plastic wrap for a type of food.

Pack the eggs with the uniform plastic wrap made by the above method at room temperature, as shown in Figure 3. Figure 3(a) shows the colors of a group of gas color-sensitive materials on the plastic wrap used to pack fresh eggs, and Figure 3 ( b) is the color of the gas color-sensitive material on the plastic wrap that has been stored for 10 days; Figure 3 (C) is the color of the gas color-sensitive material on the plastic wrap that has been stored for 15 days. It can be seen that the color of the gas color-sensitive material dots in the middle row on the plastic wrap in Figure 3(b) has changed after being stored for 10 days, and the color of the gas color-sensitive material dots in the bottom row on the plastic wrap after being stored for 15 days The color of the points is also changed. Therefore, the freshness and quality of the packaged eggs can be determined by the color change of the gas color-sensitive material on the plastic wrap.

The specific type of fresh-keeping film made by the above method is used to pack fish at normal temperature, as shown in Figure 4: Figure 4 (a) shows that the color of the gas color-sensitive material on the fresh-keeping film of fresh fish that has just been killed is yellow, and Figure 4 ( b) shows that the color of the gas color-sensitive material on the plastic wrap turns straw yellow after 4 hours; Figure 4(C) shows that the gas color-sensitive material on the plastic wrap turns blue after 1 day. Thus, the freshness and quality of the food can be determined through the color change of the gas color-sensitive material on the plastic wrap.

Example 2

The selection of gas color-sensitive materials is consistent with the method in Example 1, and acid-free paper is used as the food packaging base material. The production method is the same as the method in Example 1, except that the gas color-sensitive material is sprayed onto the acid-free paper instead of the plastic wrap by point spraying.

    The unified packaging materials made in Example 1 and Example 2 can be used as anti-counterfeiting packaging materials for cosmetics. Figure 5 shows the colors of gas color-sensitive materials of two commonly used perfumes in the market. Figure 5(a) is the unique color of the gas color-sensitive material on acid-free paper and Lancome (LANCOME) sensory hypnotic perfume, Figure 5(b) is the color-sensitive material on acid-free paper and Boss (HUGO BOSS) Uke The unique color after the effect of women's perfume. This shows that every kind of perfume has its unique fragrance, and the effect of these fragrances and the gas color-sensitive material on the packaging material can produce its unique color, therefore, the packaging material made by the present invention can be used for the anti-counterfeiting packaging of cosmetics, In the same way, anti-counterfeiting packaging materials for products such as medicine and chemical industry can also be used.

Claims (2)

1. the manufacture method of the packing of an energy perception food freshness is characterized in that adopting successively following steps:

A,At different types of food, select for use the smell that this food spoilage is given out that the different gas look quick material of change color is arranged;

B, the insurance film of selecting food stage for use or acid-free paper are as the packaging for foodstuff base material;

C, different gas look quick materials is dissolved in respectively in the corresponding organic solvent to form concentration be the different gas look quick material solution of 0.1～0.5mol/L;

D, add stabilizer in different gas look quick material solutions, the concentration of stabilizer is 5mol/L;

E, the product that gained is different respectively with point-like at interval, are equably painted one group gas look quick material lattice array every a segment distance L=10-15cm with ink-jetting style in packaging for foodstuff base material central authorities, the diameter of each gas look quick material point is 1-5mm, and oven dry is respectively organized gas look quick material lattice array and promptly made the unified type packing that are used for varieties of food items; Or with a certain product of gained in packaging for foodstuff base material central authorities every identical distance with ink-jetting style with the point-like interval, coat a gas look quick material point that diameter is identical equably, all gas looks quick material point forms row, dries each gas look quick material point and promptly makes the obligatory type packing that are used for a certain based food.

2. the manufacture method of the packing of a kind of energy perception food freshness according to claim 1, it is characterized in that: described stabilizer is a dibutyl phthalate.

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