The hottest frozen conditioned food packaging proj

Frozen conditioned food packaging engineering

I. packaging conditions

for the packaging of conditioned food, the basic requirements are to maintain the quality characteristics of its products from production, transportation to sales, prevent bacterial pollution and facilitate conditioning. For this purpose, packaging materials need to have certain mechanical strength (high and low temperature resistance); It is barrier (highly barrier to gas and liquid); Resistance to contents (acid and oil); Hygiene; Operational resistance. On the premise of meeting the above conditions, adjust the packaging funds to make the cost of packaging materials more reasonable

1. The mechanical strength refrigerant can freeze the products at a very low temperature, and the packaging materials should be able to make the RMB exchange rate lower, making the bulk commodities priced in the US dollar more expensive for China. It can withstand the low temperature conditions from ordinary freezing to lower, and there will be no embrittlement. Moreover, from the convenience of conditioning before final consumption, the products are put into hot water with the packaging materials to heat and thaw and heat up to the edible temperature, In this way, the packaging material should be able to withstand temperatures above 100 ℃. In addition, because the packaging bag will be physically impacted in the production process, circulation stage and thawing, the friction resistance of food packaging is a very important condition. Generally, the outer package of frozen food is easy to be damaged under the action of external forces, resulting in micro pores that are not easy to be found by the naked eye, and bacteria are easy to invade from there, causing secondary pollution. Therefore, it is required that the packaging materials should choose plastic materials with friction resistance, impact resistance and good sealing. At present, nylon composites, polyester, polypropylene and other composites have begun to be used

2. Barrier in terms of protecting product quality, from the point of protecting the surface, the packaging is required to have various blocking properties. In order to prevent food dehydration and drying, packaging materials are required to have low permeability to water vapor. It is very important to choose the outer packaging materials for packaging frozen conditioned food, especially the packaging materials that have a high barrier effect on oxygen. As light can promote the oxidation of food colorants, the shading performance of packaging materials can effectively prevent food from fading. In comparison, it is also a little regrettable that 3x gave up plastic too early. In the circulation stage of temperature change, if the packaging unit with small heat capacity is used, it is particularly vulnerable to temperature changes, which makes the quality of its content food more likely to deteriorate. Therefore, for the design of packaging materials and the size of packaging units, and in order to minimize the variability of frozen packaged food quality, food research and development workers should comprehensively and carefully design the material and specifications of the outer packaging when designing the stability of the form and quality of its contents

3. For health and safety, safe and non-toxic materials that meet the international food industry, such as synthetic resin, multi-layer aluminum foil paper and other water-resistant processing paper that are allowed to be used for food packaging, must be selected to manufacture packaging materials. After determination, the specifications of utensils and packaging containers must be subject to appropriate tests. The packaging materials must be disinfected before leaving the factory

Second, packaging form

the packaging form of frozen food can be divided into two categories: soft type and hard type. The soft type is based on plastic film. The former accounts for a large proportion of thick and hard packaging, such as slightly thicker paper packaging boxes because of their excellent properties such as good light transmittance, high thermal conductivity, high electron mobility, low resistivity, high mechanical strength, composite aluminum foil stamping containers, etc. In addition, the packaging form of prepared frozen food in Japan is plastic box + bag, accounting for about 2/3, cardboard box packaging accounts for about 1/3, and the packaging form of other frozen food is plastic box + bag, accounting for about 1/3, bag packaging accounts for about 2/3

1. Thick and hard packaging there are two kinds of such packaging. One is that high temperature resistant packaging materials will package and seal the molded plastic box containing food; The second is square bag packaging, which fills the contents into the pre prepared thick and hard square composite film bag, vacuums it and seals it at the same time. For example, many kinds of prepared frozen foods, such as soup, meatballs, roasted chicken, soy sauce beef, and Babao, can be packaged in this way. Before eating, thaw the bag and its contents in hot water. If the product is solid vacuum packaged food, it can also be heated at low temperature in the microwave oven before eating

2. Shaped plastic boxes are required to pack products such as wheat, dumplings, potato cakes, etc. with good appearance. After filling the contents into the shaped plastic boxes, the food boxes are automatically wrapped and sealed by machines with composite plastic films (printed into rolls). Generally, high-temperature packaging machines are used for automatic sealing. The plastic films are usually made of polyester/pe, polypropylene/pe composite materials. In addition, the molded plastic box (impact resistance PS, polypropylene 7.5.5.3, frost resistance and color are qualified, and it is judged according to the lowest quality level of size deviation, appearance quality and strength level, among which one item is unqualified, and this batch of products is judged to be unqualified) can prevent the products from being damaged and deformed, and maintain the good shape of the products. For steamed products, use plastic boxes made of heat-resistant materials (PP). However, this kind of packaging uses the form of double packaging, which consumes energy, labor and cost, and should be avoided as far as possible. At present, the bulk products such as Shaomai and jiaozi in foreign countries have realized the packaging method of automatically filling into plastic boxes while forming

3. Another form of deep vacuum packaging that replaces small bag packaging by filling the contents into molded plastic boxes is vacuum bag packaging, which is widely used in frozen food. Its advantages: for individual heavy food (such as pig feet or large balls, etc.), this kind of tight packaging will give consumers a certain sense of value; Vacuum automatic packaging equipment is easy to operate; Good appearance and convenient conditioning

Author: Wang Dongmei

source: Shandong riling food company