We manufacture and supply various modified atmosphere packaging machines with different specifications and prices. Please kindly tell us the packaging requirement, packaging dimension and productivity you need so that we can provide a suitable packaging solution for you.
All of our MAP packaging machines are qualified for MAP packaging, Vacuum-Sealing packaging and Sealing-Only packaging.
Modified Atmosphere Packaging Machines
What is MAP modified atmosphere packaging
MAP modified atmosphere packgaing is a premium food packaging technology that is designed to extend food’s shelf-life by changing the composition of the atmosphere environment inside food containers. Modified atmosphere packaging is often used for packaging of fresh food products, including beef, pork, poultry, fish and seafood, cheese, vegetables and fruits, cured/smoked meat poultry and fish products, snacks, etc.
The ultimate goal of modified atmosphere packaging is to keep the original, natural and fresh flavor, taste and color of food products for a longer period without addition of preservatives. This feature makes MAP packaging super favorable in fresh food retailing.
MAP modified atmosphere packaging machines
As a professional food packaging solution provider, we manufacture the following types of modified atmosphere packaging machines:
- Vertical type of modified atmosphere packaging machine MAP420/1S and MAP420/2S： MAP420/1S has 1 mold while MAP420/2S has 2 molds that work alternatively in opposite directions of the machine. For specifications and features of the machine, please visit product page.
- Continuous modified atmosphere packaging machine: Features a set of molds that rotate inside the machine, this MAP machine enables automatic and fast-speed packaging of trays, bowls and cups. For details, please visit product page.
- Thermoforming packaging machine for modified atmosphere packaging: Thermoforming MAP machine uses a roll of bottom film to form the container automatically, the formed contained can be flexible or rigid.
Common features of our modified atmosphere packaging machines
Different modified atmosphere packaging machines have different features and specifications, but still they have some features in common:
- All the machines are made of food-grade SUS304 stainless steel, totally inline with food safety standards, and guarantees long service life.
- The mold of modified atmosphere packaging machine is customized according to customer’s request, fit for products and containers of various shapes and dimensions
- Our modified atmosphere packaging machines are multifunction. With gas mixer and gass ources, they can do modified atmosphere packaging. They also have vacuum-sealing function and sealing-only funciton.
- There are available options for date printing, automatic loading, etc.
How does modified atmosphere packaging machine work
Despite of different specifications of the modified atmosphere packaging machines, all our MAP machines follow the vacuum-gas filling process, which is different from traditional gas-flushing type of MAP packaging.
Vacuum-Gas filling: The whole process is completed in the vacuum chamber of modified atmosphere packaging machine. First step is to evacuate the air in the vacuum chamber and food container by vacuum pump; Second step is to fill gas sources into the container to have the expected atmosphere around the food product.
Advantage of vacuum-gas filling over traditional gas-flushing: “gas-flushing” uses modified atmosphere air to flush the food container to replace the air, the oxygen residual is high and waste a lot of gas source. “Vacuum-gas filling” make the food container to vacuum status first, which guarantees minimum oxygen residual to lower than 0.5%. Modified atmosphere packaging machines use “Vacuum-gas filling” process can make sure that the composition of filled-in gas doesn’t change because of residual oxygen.
Simply put, the shelf life of food products packed by “vacuum-gas filling” type modified atmosphere packaging machine is longer, because the mixing ratio of the filled in air doesn’t not change during the packaging process.
Key control points in modified atmosphere packaging
MAP modified atmosphere packaging is considered as one of the most complicated food packaging technology. The quality control of MAP packaging involves quality of modified atmosphere packaging machines, the composition ratio of the gas filled into the container, specifications of modified atmosphere packaging materials, the environment of the packaging workshop, the storage environment of the final packages.
1. Quality of modified atmosphere packaging machine: Our MAP machines are made of SUS304 stainless steel, make sure no contamination to food products; Modified atmosphere packaging machine uses Vacuum-Gas filling process minimizes the oxygen residual so that food shelf life is guaranteed.
2. Composition of the air filled into the container: For different food products, the atmosphere required to extend food shelf life is very different. It is highly recommend that experiment is performed before massive food packaging production, to determine the best air composition ratio for your food products.
3. Specifications of modified atmosphere packaging materials: MAP packaging materials usually include LDPE, LLDPE, HDPE, PP, PET, PVC, PVDC, EVOH, Nylon, etc. These materials offer different mechanical characteristics and most importantly, they have fundamentally different permeability to O2, CO2 and water vapor. For different food products, the requirement of gas permeation is very different when it comes to shelf-life extending. Depending on the specific requirements of gas permeation, different materials or material combinations shall be used to adjust the modified atmosphere packaging system. For exmple, polyamide is of very low permeability to O2 and CO2, polypropylene and EVA are of moderate permeability, LDPE is of high permeability.
In the modified atmosphere packaging of fresh vegetables and fruits, as the food products remain activity after they are packaged, in order to avoid the accumulation of moisture on the top sealing film, materials have a high permeability to water vapor are often used, such as PLA or EVOH, which have low permeability to O2 and CO2.
4. The environment of the packaging workshop shall be strictly inline with local law of food production and packaging. Make sure ther’s no unexpected bacteria and microorganism that might contaminate the food and container.
5. Storage and transportation of final packages: After modified atmosphere packaging, the final packages shall be stored and transported in safe, clean and low-temperature environment.
Benefits of modified atmosphere packaging
Modified atmosphere packaging is meant to lock the freshness of natural and raw food products in their containers for a certain period of time. MAP packaging keeps the orignal flavor, color, texture and nutrition of food products by modifying the atmosphere surrounding the food products, eliminate the use of addictives. Following are the benefits of modified atmosphere packaging for food products:
• Modified atmosphere packaging offers longer shelf life
MAP packaging slow down the spoilage of food products by changing the surrounded atmosphere. Combined with low temperature storage, Modified Atmosphere Packaging can significantly extend food freshness and shelf life. For different food products, the extended shelf life is different. Normally, MAP products keep a high quality over a longer period of time and arrive at the consumer in the best possible condition.
• Less food waste
The shelf life of food products are extended to an expected period, as a result, waste disposal due to spoiled food can often be reduced. This benefits the whole food supply chain, including food storage, food transportation, food presentation at grocery stores, and consumer use.
• Expand target markets
Food products in modified atmosphere packaging are eligible for new geographic markets because of the longer shelf life. Before MAP packaging is used, fresh food products can only be sold at local market. But with the help of modified atmosphere packaging, they can be delivered to far away cities, provinces, or even different countries.
• Minimum use of preservatives
Packaging under a modified atmosphere extends the shelf life of food, meaning in many cases that the use of preservatives can be reduced or even completely eliminated. Consumers get products that do not contain artificial additives. This feature helps to enhance your brand credits to consumers, because of the more and more concern of natural food diet.
• Appealing package design
Next to functional aspects, the design of the packaging plays a significant role in the competition for consumers. The look-and-feel and the quality impression influence the purchasing behaviour. Modified Atmosphere Packaging is very well suited for the most appealing packaging design and presentation of the food product.
Main air type used in modified atmosphere packaging
The type and proportion of gas used in the packaging is mainly decided by the type of food in the package. Some products only need nitrogen filling, while others might need mixed air of nitrogen, dioxide carbon and oxygen. Following is the modified air composition for your reference. We always recommend that you consult a professional food technologist or do experiment for the exact mixing ratio of gases before start the production.
Carbon dioxide (CO2) and nitrogen (N2) are mainly used as protective gases in food packaging. Carbon monoxide (CO) or argon (Ar) is also common in some countries. Oxygen (O2) is also used in some cases.
Oxygen (O2) essentially causes food to spoil due to oxidation and forms the ideal preconditions for aerobic microorganisms to grow. As a result, oxygen is frequently excluded from modified atmosphere packaging. In some cases – typically red meat – processing is deliberately carried out with high oxygen concentrations, in order to prevent the red colour from becoming ‚pale, and to inhibit the growth of anaerobic organisms.
Carbon dioxide (CO2) is colourless, odourless and tasteless. It has an oxidation-inhibiting and growth-inhibiting effect on most aerobic bacteria and moulds. The gas is frequently used to increase the shelf life of food. The shelf life of packaged or stored food is normally longer, the higher the CO2 content. Nevertheless, many products can become sour if the dosage is too high. In addition, the gas can diffuse out of the packaging or be absorbed by the product – and the packaging thereby collapses. The use of supporting or filling gases can slow down this effect.
Nitrogen (N2) is an inert gas and owing to its production process, is typically relatively high purity. It is usually used for displacing air, especially atmospheric oxygen, in food packaging. This prevents the oxidation of food and inhibits the growth of aerobic microorganisms. It is frequently used as a supporting or filling gas, as it diffuses very slowly through plastic films and hence remains longer in the packaging.
Carbon monoxide (CO) is colourless, odourless and tasteless. Similar to oxygen, carbon monoxide is sometimes used to retain the red colour of, primarily, meat. The required concentrations are very low. In some countries, including the EU, the use of carbon monoxide for modified atmospheres is nonetheless prohibited in foods.
Argon (Ar) is inert, colorless, odorless and tasteless. Owing to the similarity of its properties to those of nitrogen, argon can replace nitrogen in many applications. It is believed that certain enzyme activities are inhibited and argon slows metabolic reactions in some types of vegetables. Due to the marginal effects and the higher price compared to nitrogen, its use is rather rare.
Hydrogen (H2) and helium (He) feature in modified atmospheres in some applications. However, these gases are not used to extend shelf life. They are used as trace gases for some leak detection systems available on the market. The relatively small molecular size of the gases allows rapid escape through packaging leaks. Since these gases otherwise have no positive properties on the food products and are expensive and not easy to handle, their use is rare. The most common method for leak testing is the detection of CO2 which is the core component in many MAP processes.
As an inert gas, nitrogen is primarily used to replace oxygen in packaging, thereby preventing oxidation. Owing to its low solubility in water, nitrogen also helps to prevent package collapse by maintaining internal volume
Air composition samples for different food products in modified atmosphere packaging
|Modified Air Composition
|Raw red meat: Beef, goat, hare, lamb, pork, rabbit, veal, horse, venison, wild boar
|70% O₂， 30% CO₂
|Raw offal: Feet or trotters, foie gras, giblets, heart, kidney, liver, neck, oxtail, sweetbread, tongue and tripe
|20% CO₂, 80% O₂
|Raw poultry: Chicken, duck, goose, guinea hen, grouse, partridge, capon, pheasant, pigeon, poussin, cornish hen, quail and turkey
|30% CO₂, 70% N₂, or 20% CO₂, 80% O₂
|Poultry, dark portions and cuts: Dark poultry mince, other skin-off poultry, skin-off chicken, skin-off turkey, sliced dark poultry, turkey mince
|30% CO₂, 70% O₂
|Raw low fatwhite fish and seafood: Catfish, cod, brill, bream, coley, croaker, dab, dover and lemon sole, flounder, grouper, haddock, hake, halibut, hoki, huss, jackfish, john dory, mullet, monkfish, pike, plaice, pollack, red snapper, sea bass, shark, skate, turbot, whiting
|30% N₂, 40% CO₂, 30% O₂
|Raw high fat oily fish and seafood: Bluefish, carp, eel, greenland halibut, herring, mackerel, pilchard, rock salmon, salmon, sardines, shad, sprat, swordfish, trout,. tuna, whitebait
|60% N₂, 40% CO₂
|Shellfish, crustaceans and molluscs: Abalone, clams, cockles, conch, crab, crayfish, cuttlefish, lobster, mussels, octopus, oysters, prawns, scallops, sea urchins, shrimp, squid, whelks, winkles
|30% N₂, 40% CO₂, 30% O₂
|Cooked, cured and processed meaet products: Bacons, beefburgers, black pudding, charcuterie, chopped pork and ham, cooking sausages, corned beef, frankfurters, haggis, hams, luncheon meats, meat jerky, meat slices, ox tongue, pastrami, pates, pepperoni, potted meats, rillettes, roast meats, salmi, smoked reindeer, smoked venison, terrines, wurst sausages
|70% N₂, 30% CO₂
|Cooked, cured and processed fish and seafood products: Bloaters, bombay duck, buckling, cod’s roe, cold smoked fish, fish galantine, fish rillettes, fish terrines, hot smoked fish, kippers, potted fish, potted shellfish, salt cod, salted anchovies, salted caviar, salted fish roes, salted jellyfish, seafood pates, smoked haddock, smoked halibut, smoked mackarel, smoked salmon, smoked trout, taramasalata
|70% N₂, 30% CO₂
|Cooked, cured and processed poultry and game bird products: Capon galantine, chicken ballotine, chicken roll, cured game birds, cured poultry, duck ballotine, duck pate, duck galantine, pheasant galantine, pigeon galantine, smoked chicken, smoked duck, smoked poussin, smoked turkey, turkey bacon, turkey ballotine, turkey galantine, turkey roll
|70% N₂, 30% CO₂
|Ready meals: Casseroles, ready meals containing fish, ready meals containing game bird, goulash, ready meals containing meat, ready meals containing offal, ready meals containing pasta, ready meals containing poultry, sauces, ready meals containing seafood, soups, ready meals containing vegetables
|70% N₂, 30% CO₂
|Convenience food products:Battered fish, seafood, meats and poultry;Bouchee/breaded: fish, seafood meats and poultry;Burritos, enchiladas, falafels, filled crepes, pancakes and rolls, kebabs, omelettes, pasties, pates en croutes, pizzas, pasta and pies containing meat, poultry fish and seafood, quiche, roule au fromage, sandwiches, satays, sausage rolls, souffies, spring rolls, stuffed pitta bread, tacos, tostadas, vol au vents
|70% N₂, 30% CO₂
|Fresh pasta products: Capelli, fettucine, funghini, fusilli, linguine, macaoni, pasta shells, spaghetti, tagliarini, tagliatelle, trenette, tubetti, vermicelli, zitioni
|50% N₂, 50% CO₂
|Bakery products: Bagels, bread puddings, breads, buns, cheesecakes, crepes, croissants, crumpets, danish pastries, fruit breads, fruit cakes, fruit pies, fruit strudels, fruit tarts, meringue cakes, muffins, nan bread, nut breads, pancakes, par-baked breads, pitta bread, pizza bases, pretzels, sponge layer cakes, swiss rolls, taco shells, tortillas, vegetable breads, waffles
|50% N₂, 50% CO₂
|Hard cheeses: Aerosol creams, butter, cream cakes, creams, custards, fresh cheeses, hard cheeses, margarine, semi-hard cheeses, sliced cheeses, yoghurts
|Grated and soft cheeses: Aerosol creams, butter, cream cakes, creams, custards, fresh cheeses, grated cheeses, margarine, sliced cheeses, soft cheeses, yoghurts
|70% N₂, 30% CO₂
|Dried food products: Coffee, milkpowder, cocoa powders, dehydrated mil, dried and salted fish, dried and salted seafood, dried beans, dried cereals, dried colourings, dried flavourings, dried fruits, dried herbs, dried lentils, dried mushrooms, dried pasta, dried snack food, dried spices, dried vegetables, flours, nuts, potato crisps, teas
|100% N₂ or 30% CO₂, 70% O₂
|Cooked and dressed vegetable products: Bean chillies, bhajis, broccoli in cheese, bubble and squeak, cauliflower cheese, coleslaw, cooked beans and potatoes, corn fritters, garlic mushrooms, lentil cutlets, other dressed salads, pakoras, pasta and potato salads, pilafs, quorn dishes, rice salads, rissoles, stuffed peppers and tomatoes, vegetable bakes, casseroles containing vegetables, vegetable pastas and crumbles, vegetable curries and dosas, vegetable flans, vegetable pilau, vegetable pie, vegetable pie, vegetarian burgers
|30% CO₂, 70% O₂
|Liquid food and beverage products: Cordials, fruit juices, liqueurs, liquid yoghurt, milk, mineral waters, oils, spirits, vegetable juices, wines
|Fresh whole and prepared fruit and vegetable products: Apples, apricots, artichoke, asparagus, aubergine, avocado, bananas, bean sprouts, beetroot, beans, broccoli, cabbages, carrots, celery, cherries, cucumber, cumquats, fennel, garlic, citrus fruits, grapes, guava, kiwi fruit, leek, lettuces, lychees, mango, marrow, melons, fruit and vegetable salads, okra, onions, other sprouts, papayas, parsnips, passionfruit, peaches, pears, peas, peppers, pineapple, plums, potatoes, radish, rhubarb, spinach, star apples, strawberries, other berries, sweetcorn, tomatoes
|90% N₂ or 5% CO₂, 5% O₂
What products can be packed by our MAP modified atmosphere packaging mahcines
Our modified atmosphere packaging machine can pack a wide range of food products, including fresh meat products, fish and seafood products, cheese dairy products, vegetables and fruits, bread and bakery, ready meals, poultry products, smoked and cured meat products, dried nuts, coffee, etc.
Meat and sausage products
Meat and sausage products, especially raw meat, are very prone to spoiling due to microbial growth, on account of their high moisture and nutrient content. No matter whether beef, pork or poultry – spoilage begins from the moment of slaughter and especially after butchering. Besides high hygiene standards and permanent cooling, modified atmospheres can significantly extend the shelf life of meat and sausage products. CO2 is the most important among the protective gases. At concentrations above 20 %, CO2 can considerably reduce microbial growth. In the case of red meat, there is also the risk of oxidation of the red colour pigments. The meat will lose its red colour, becoming grey and unappetising in appearance. This oxidation is especially prominent with beef. A high oxygen content in protective gas packaging can prevent oxidation. A low carbon monoxide content (approx. 0,5 %) can also help to retain the red colour of meat. However, the use of this gas is not allowed in the EU, for example. Poultry is especially sensitive to rapid spoilage and is therefore subject to higher requirements for permanent cooling. Here too, a modified atmosphere with CO2 content will extend the shelf life. A high oxygen content is also used for poultry without skin so as to retain the colour of the meat. The CO2 can partly be absorbed by the foods. To prevent the packaging from collapsing, nitrogen is used as a supporting gas.
Sausage and meat products, e.g. marinated or smoked meat pieces, react very differently depending on the preparation. Longer shelf-lives can be afforded by the use protective gases right from the start. The CO2 content should not be too high with these products, in order to prevent a sour taste.
Fish and Seafood products
Fish and seafood are some of the most sensitive foods. They are at risk of rapidly declining in quality and spoiling even shortly after the catch. The reason for this lies in the neutral pH value as an ideal precondition for microorganisms as well as special enzymes that negatively affect taste and odour. Fish, which is rich in fatty acids, also becomes rancid quickly. The most important element for a longer shelf life is cooling close to 0° Celsius. Modified atmospheres with minimum 20 % CO2 also retard the growth of bacteria. CO2 components around 50 % are frequently used. Higher CO2 concentrations can lead to undesirable side effects such as liquid loss or a sour taste. In the case of low-fat fish and shellfish, O2 is also used in the packaging. This prevents a fading or loss of the colour, while at the same time serving as a growth inhibitor for some types of bacteria. When dealing with shellfish and crustaceans, special attention should be paid to ensuring a CO2 content that is not too high. This can be discerned most clearly by a sour taste, while these products absorb CO2 the most, as a result of which the packaging can collapse. Nitrogen as an inert supporting gas prevents this effect.
Cheese is predominantly spoiled by microbial growth or rancidness. A continuous cooling chain essentially extends the shelf life of products. With hard cheese, there is a risk of mould formation upon contact with oxygen. As a result, vacuum packaging was frequently used in the past, even though these are awkward to open and can leave unattractive marks behind on the product at the same time. CO2 effectively prevents mould formation, but does not otherwise affect the maturation of the cheese. Soft cheese can quickly become rancid. This problem can also be tackled with CO2 modified atmospheres. However, as soft cheese absorbs CO2 to a significantly higher extent, there is a risk of the packaging collapsing. A correspondingly lower CO2 content should therefore be chosen. In the case of milk products such as yoghurt or cream, there is a risk of the products absorbing too much CO2 and becoming sour. A lower CO2 content should therefore be chosen.
Milk powder, above all for use in baby food, is a highly sensitive product. It is especially important to ensure that oxygen is displaced from the packaging in order to extend the shelf life. In practice, packaging is carried out in pure nitrogen with as low a residual oxygen content as possible.
Bread and Cake
With bread, cake and biscuits, the shelf life is primarily affected by potential mould formation. A high standard of hygiene during production and packaging can significantly minimise this risk. Packaging involving a modified atmosphere with CO2 and without oxygen largely prevents the products from becoming mouldy and extends the shelf life. To prevent the packaging from collapsing owing to CO2 absorption by the products, nitrogen is used as a supporting gas in many cases.
Fruit and Vegetables
Modified atmospheres in packaging make it possible to offer consumers fresh and untreated products – in other words succulently fresh fruit and vegetables – with a long shelf life. At the same time, fruit and vegetables are subject to very special requirements in regard to the nature of the packaging and atmosphere. This is because – in contrast to other food – fruit and vegetables continue breathing after the harvest and consequently require an oxygen content in the packaging. Furthermore, the packaging film does not have to be fully tight. By taking the product’s breathing and the permeability of the film, typically via micro-perforation, into account, the composition of carbon dioxide, nitrogen and low amounts of oxygen ideal for the product can be maintained. The term used here is an EMA (equilibrium modified atmosphere). The gas composition is individually adapted to the corresponding product.
Thorough cleaning along with hygienic processing are the fundamental preconditions for long-lasting freshness. Modified atmospheres, in conjunction with corresponding cooling, can be used to extend the shelf life of fresh produce, while achieving an attractive packaging design at the point of sale.
Pasta and ready-made meals
The nature and composition of fresh pasta and, in particular, readymade meals are very different. Above all, multi-component products such as ready-made pizzas or sandwiches contain many different foods with differing shelf lives and spoilage properties. In the majority of cases, modified atmospheres can significantly extend the shelf life without using oxygen. Mixtures of CO2 and nitrogen are used here. The concentration of the gases is oriented to the content of the product. If, for example, there is a risk that large volumes of CO2 will be absorbed by the product, the nitrogen content should be chosen higher to prevent the packaging from collapsing.
Snacks and Nuts
Snack products, for example potato crisps or peanuts, primarily involve problems associated with the fat content of the food. There is a risk of oxidation, whereby the products can quickly become rancid if the packaging is not optimal. To extend the shelf life, it is therefore important to minimise the contact with oxygen. Modified atmospheres with 100 % nitrogen are frequently used. In this way, a premature spoilage can be prevented, while these atmospheres also provide protection from mechanical damage to sensitive products, e. g. potato crisps in conventional packets.
Gases or gas mixtures are often used to protect wine in the different phases of its production process and to retain the quality of the product. They are mainly used to avoid contact with oxygen and prevent microbial deterioration. The tank headspace is replaced with an inert gas or a gas mixture, for example of CO2, N2 or Ar. The composition of the gases is chosen according to the type of wine.
As a dried product, coffee is relatively insensitive to spoilage by microorganisms. However, the risk of the fatty acids it contains oxidising and making the product rancid is greater. To prevent this, oxygen is excluded from coffee packaging. Instead, a modified atmosphere comprising pure nitrogen is frequently used in coffee sachets or capsules.
What’s the shelf life of food products in modified atmosphere packaging
1. Fresh meat and poultry products
The gas mixture for modified atmosphere packaging of fresh pork, beef and mutton is composed of CO2, O2, etc. High concentration of O2 oxidizes myoglobin in meat to oxymyoglobin, which can keep the bright red color of fresh meat; CO2 is used to inhibite the activity of aerobic bacteria. The shelf life of read meat is 7-10 days at 0-4°C environment.
Fresh poultry uses CO2, N2 and other fresh-keeping gases, and the shelf-life can reach 15-30 days at 0-4 ℃ environment, 2-5 days at room temperature.
2. Fresh vegetables, fruits and mushrooms
Whole or fresh cut fruits and vegetables still maintain the metabolic respiration activity of absorbing O2 and expelling CO2 after packaging. If the O2 content in the package decreases and the CO2 content increases, the fruits and vegetables can maintain weak aerobic respiration without anaerobic respiration, reduce the metabolic rate, and prolong the shelf life.
Modified atmosphere packaging of fresh fruits and vegetables involves mixing of O2, CO2 and N2. The shelf-life of packed vegetables and fruits is determined according to the species and freshness, such as strawberries, mushrooms, lychees, peaches, leafy vegetables, etc. The shelf life at 0-4°C is 10-30 days. A low barrier film is used.
3. Ready meals and smoke chicken, cured meat, etc
For modified atmosphere packaging of food products like ready to eat meals, stewed vegetables, cured meat, smoke chicken, roast ducks, etc., the protective gas is generally composed of CO2, N2 and other gases. After modified atmosphere packaging, the preservation gas forms a protective film on the surface of the food, so as to achieve the purpose of bacteriostasis preservation and preservation of food nutrients and the original taste, flavor and shape.
The shelf life is more than 5-10 days below 20℃, and 30-60 days at 0-4℃; after pasteurization (about 80℃), the shelf life at room temperature is more than 60-90 days. A high barrier film is required.
The deterioration of baked goods is mainly caused by mildew, so the purpose of modified atmosphere fresh-keeping packaging is mainly to prevent mildew and maintain flavor. The fresh-keeping gas consists of CO2 and N2. After modified atmosphere packaging, the shelf life of rice and flour food such as cakes and breads at room temperature is 15-60 days; the shelf life of moon cakes at room temperature is 30-90 days. The packaging film needs to use a composite plastic film with high gas barrier properties to maintain the gas concentration in the packaging.
5. Fresh fish and seafood products
Aquatic products such as fresh fish and shrimp are perishable foods with high moisture content. Anaerobic bacteria are one of the corruption factors of fresh aquatic products during low temperature storage, and produce toxins that are harmful to human health. The fresh-keeping gas consists of O2, CO2 and N2.
Modified atmosphere packaging of fatty fish is the main factor of spoilage due to fatty oxidizing acid, and the protective gas is composed of CO2 and N2.
Modified atmosphere packaging of fresh aquatic products, according to the variety and freshness, the preservation period at 0-4°C is 15-30 days. The packaging film needs to use a composite plastic film with high gas barrier properties to maintain the gas concentration in the packaging.
Frequently asked questions
We need to launch modified atmosphere packaging for a new project, what are the devices we need to prepare?
To launch a new modified atmosphere packaging project for your food business, the follow items are required:
1). Choose the right modified atmosphere packaging machines, according to your product features and productivity requirements.
Food-grade high-purity gas sources
2). Gas mixer: When replace the package atmosphere with mixed gas, a gas mixer is required to mix the gas sources at a certain ratio, and connect to the gas inlet of the modified atmosphere packaging machine. We can prepare the gas mixer for you, or you can purchase it from other suppliers. We usually recommend china made gas mixers that costs about USD4000, and Germany brand WITT gas mixer.
3). Gas analyzer to keep tracking modified atmosphere packaging quality, more specifically, randomly check the gas composition of packages
4). Air compressor to generate compressed air which is the driving source of modified atmosphere packaging machine.
5). Appropriate packaging materials: food products of different features require different packaging materials
Why the packages collapse and how to resolve the problem?
Modified atmosphere packaging collapse often happens, because CO2 inside can diffuse out of the package, or be absorbed by the food product, which makes the air pressure inside the package lower than outer air pressure, which causes package collapse. This issue often happends to MAP packages of fresh meat, fresh fish and seafood, soft cheese, bakeries, etc.
The common solution of this issue is to fill nitrogen as supportive gas, which can slow down the collapse effect.
Is it safe to eat food in modified atmosphere packaging?
Yes. Modified atmosphere packaging is meant to extend food shelf life in a safe way. The gases (oxygen, nitrogen, carbon dioxide, etc) used for MAP packaging are totally food-grade and allowed by authorities. In fact, the inside atmosphere is modified to slow down the spoilage of food, keep the food as fresh as possible, not to change the status of the food products.
What are the key points that determine the quality of modified atmosphere packaging?
1) Quality of modified atmosphere packaging machine
2) Oxygen residual rate
3) Purity of gas sources
4) Gas composition, mixing ratio
5) Packaging environment temperature control
6) Packaging environment hygiene management
7) Storage and transporation environment of final packages
Can I keep modified atmosphere packaging food in freezer
Modified atmosphere packaged food can be frozen, but please confirm with your material supplier to ensure that the modified atmosphere packaging material you use is suitable for freezing. In addition, the frozen-preserved modified atmosphere packaged food will lose a lot of water after thawing, which will affect the color and flavor of the food. In most cases, modified atmosphere packaged foods are suitable for storage in a refrigerated environment of 0-4 degrees Celsius.
Why the color of chilled meat in modified atmosphere packaging turn dark
The meat color turn to dark red because the oxygen content in the modified atmosphere is too low, and the myoglobin in the meat cannot be converted into oxymyoglobin, so the color becomes darker and purple-red. In order to maintain the good color of chilled meat, the oxygen content in the package needs to be 70-80%.
The change of meat color is closely related to myoglobin. Myoglobin is a complex protein composed of globin and heme composed of a polypeptide chain, and heme contains iron ions, which are in the form of divalent iron. in the dynamic equilibrium of the reduced and oxidized states. The reduced iron ion has the ability to combine with oxygen, and the change in its combination with heme is the main factor leading to the color change. When the iron ion and heme lack the ligand at the sixth position, it is called deoxymyoglobin. , the meat color is dark purple at this time. When the oxygen atom occupies the sixth ligand, oxymyoglobin is formed, and the color is bright red at this time, so heme has the function of storing and transporting oxygen. When myoglobin undergoes oxidation and divalent iron ions become trivalent iron ions, it is called methemoglobin, which does not have the function of transporting oxygen, but methemoglobin also reduces the color of meat. Therefore, controlling the transformation of myoglobin is an important way to inhibit the color change of meat.
Modified atmosphere packaging technology is a commonly used storage method for chilled meat. It prolongs the shelf life of meat by changing the gas composition of the meat storage environment. Among them, oxygen, nitrogen, carbon dioxide and carbon monoxide are commonly used gas components. Packages with different gas compositions are all helpful in extending shelf life, but show different results in terms of color loss prevention. The anaerobic environment created by carbon dioxide and nitrogen can maximize the shelf life, but due to the lack of oxymyoglobin, the meat is dark red; the hyperoxia environment can maximize the content of oxymyoglobin and keep the color of the meat. Bright red state, but also due to the presence of oxygen, causing fat oxidation, the free radicals formed by oxidation will promote the formation of high iron myoglobin, and its color will deteriorate rapidly with the extension of storage period; carbon monoxide can combine with myoglobin, It forms cherry red carbon monoxide myoglobin, and its properties are stable, the color change is not obvious, and carbon monoxide has an antioxidant effect, which can inhibit fat oxidation, but due to the toxicity of carbon monoxide, its dosage is very limited, and the color protection performance is also greatly reduced.
In order to make up for the lack of a single gas in preventing color loss, mixed gas is the most commonly used gas composition for modified atmosphere packaging. Commonly used gas compositions are high oxygen type (O2, CO2 or N2), CO type (CO, CO2 or N2) and mixed type (O2, CO2 or N2, CO). In terms of stability, CO type > mixed type > high Oxygen type, but CO type has a cherry red color, which has a negative impact on consumers’ purchase intention. In the sensory evaluation, high oxygen type > mixed type > CO type, but the high oxygen type has a short stability period and is suitable for products with a fast turnover rate, but not suitable for products with a long storage period. In terms of comprehensive indicators, hybrid type> hyperoxic type> CO type, hybrid type can not only reflect the sensory index of hyperoxic type, but also avoid the problem of CO type color distortion, which is an important direction for the development of modified atmosphere packaging.
What are the disadvantages of modified atmospere packaging
1) The cost of modified atmosphere packaging is higher than regular vacuum packaging, including the cost of modified atmopshere packgaing machines, gas sources, gas mixer, packaging material.
2) MAP packaging requires more attention to temperature control
3) Modified atmosphere packaging requires more research before launching the project, for each product the gas composition is different.
4) Because of the filled gases, MAP package volume is larger than vacuum packaging and vacuum skin packaging, which leads to higher storage and transportation cost.
5) CO2 dissolving into the food could lead to package collapse and increased drip
6) Increase water condensation within the package, which hurt the package appearance and encourage fungal growth.
I’d like to buy modified atmosphere packaging machine from you, what information should I provide?
To purchase modified atmosphere packaging machine from us, please kindly provide the following information:
1) What product do you need to pack
2) Packaging dimension required, length*width*depth
3) The productivity of the MAP packaging machine, how many packs/hour
4) If any additional function is required, including automatic loading, date printing, label applicaiton, metal detector, etc
5) If registration mark sensor is needed (for printed sealing film)
6) Please send us tray samples so that we can design the mold and test the machine
7) Confirm the electricity voltage and frequency
8) If you prefer your company LOGO printed on the machine
9) Any other requrement, please let us know
I only need to fill nitrogen into the food packages, can your machines do the job?
Our modified atmosphere packagings are multi-function. If you only need to fill nitrogen into the packages, gas mixer is no longer needed. The nitrogen gas cylinder can be connected to the MAP machine directly.
Why the atmosphere composition changes after packages stored for some time
This is caused by several reasons, in some cases, it’s a normal phoenomenon, otherwise, that’s a problem need to be fixed.
1) Check if the package is intact, whether ther’s damage to the tray or sealing film, or bag sealing quality that allows exit of atmosphere and air inlet.
2) Check the packaging material permeability. Atmosphere changing might be caused by the low barrier sealing film. The use of low barrier or high barrier sealing film is different for different food products.
3) The vacuum process wasn’t done perfectly, so some air is trapped in the food texture and then released into the atmosphere.
4) The atmosphere and food product interacts by absorbing, dissolving or producing gas.