FI96915B - Procedure for providing storage-resistant liquid food products - Google Patents

Description

96915

The invention relates to a process for the production of storage-stable liquid nutrient preparations. The invention relates to a process for the production of storage-stable liquid nutrient preparations.

Liquid nutrient preparations include all fruit juices, juice blends and beverages with or without preservatives. Examples of these are citrus fruit preparations, for example orange juice and citrus-flavored preparations, with or without preservatives, for example sodium benzoate or potassium sorbate, fruit preparations such as grape, apple or strawberry drinks or juices, and vegetable juices and vegetable juices. Liquid nutrient preparations also include dairy products such as milk. Liquid nutrient preparations also include sauces, puddings, vanilla and other sauces, extracts and soups. They also include low-alcohol non-acidic preparations, such as citrus wine coolers.

25: Various packaging has been used for such preparations, such as metal cans, glass cans and plastic or cardboard cans.

Although plastic and cardboard packages are generally less expensive than glass-30 packages or metal cans, the problem has been to produce plastic or cardboard packages that provide adequate shelf life without refrigeration.

Liquid nutrient preparations are treated in many different ways to clean them from contaminating microbes such as yeast, mold and bacteria. If, after treatment, the preparations still contain any of these organisms, they will • deteriorate rapidly. Although micro-organisms in juices or other beverages are controlled by methods such as pasteurization or microwave or gamma irradiation, there is a risk that contaminants will come from the surrounding air or empty packaging during filling.

5

One treatment method commonly used may be referred to as the "hot filling method". The preparation is generally pasteurized at about 90 ° C and then filled into packages at 82 ° C to 88 ° C, then the filled packages are sealed, inverted to sterilize the lid 10 with the hot preparation, and cooled to ambient temperature. Although the hot filling method is widely used, it has disadvantages. It requires specially designed and expensive packaging due to the temperature at which filling takes place. For example, a six-layer can is commonly used, which contains polyethylene as the overlapping layers, a bonding barrier layer, an aluminum foil barrier, a second bonding layer, a cardboard layer and a polyethylene layer. A binding barrier layer is needed because otherwise lamination will open between the polyethylene layer and the foil due to the high filling temperatures. The filling temperature is detrimental to some preparations, for example orange juice, which deteriorates rapidly due to oxidation at high temperatures, which causes a rapid deterioration of the taste. Foaming and splashing also tend to occur. Perhaps the most serious problem is that there is a vacuum after cooling, which means that an extremely tight and efficient sealing method must be used, as otherwise air will be channeled in, taking with it microorganisms that cause contamination of the preparation. For example, if the orange juice is filled by the hot filling method into the type of cardboard brush wrapper normally used for milk, the adhesive used to close the top of the milk cans, which is loose to form a spout, would be completely insufficient to cope with the vacuum resulting from the hot filling. The primary areas from which air and the microorganisms it transports are likely to channel are from the center of the brush or through 35 sides and down the center. If a very strong closure is then used to avoid channeling, it will be difficult or impossible for most consumers to open the brush cover to form a spout.

tl 3 96915

Hot filling problems can be avoided with cold filling. The preparation is pasteurized at 85 ° C to 90 ° C and cooled to ambient temperature for filling into non-sterile containers. The product must be kept refrigerated at all times and usually has a shelf life of two weeks.

5 Cold filling can also be used if sufficient preservatives are present. The preparation contains preservatives, for example sodium benzoate or potassium sorbate. Drinks are kept at room temperature for three to six months, but juices should be kept refrigerated because the preservative only prevents the growth of microorganisms — 10 but does not destroy them. If the initial microbial content is too high, the preservative will not be able to stop rapid growth, resulting in spoilage. A positive feature of the preservative method is that the preparation can be packaged in any package. The downside is that preservatives used at concentrations below 500 ppm are ineffective and above this level they leave a burning taste in the product.

The very recent method is known as the "aseptic" method. It involves filling a pre-sterilized preparation into a pre-sterilized package in a sterile environment. The preparation is pasteurized at 90 ° C for 15 seconds and then cooled to ambient temperature for filling. The package is treated with hydrogen peroxide or steam before filling. The filling device is in a state maintained at elevated atmospheric pressure. Examples of aseptically filled products may be • 25 puddings packaged in a "Brik" pack and some shelves stored in plastic packs. It is a very complex method that requires high capital and maintenance costs, and problems on the production line cannot be allowed. Production line speeds are generally low.

30: Although post-pasteurization or sterilization after filling and sealing has been used in the beer industry and for some carbonated beverages containing juices, this has included glass packaging or metal cans. It is believed that no useful method for post-packaging when the packages are plastic or plastic-coated paperboard has been developed.

4,96915

The object of the invention is to use a post-pasteurization method to solve the problems which are characteristic of the use of packages made of plastic or plastic-coated cardboard.

The invention relates to a process for the production of storage-stable liquid nutrient preparations, characterized in that it comprises the steps of: a) cold filling a plastic or plastic-coated easy-to-open brush cover package with a non-carbonated liquid nutrient preparation without thermophilic b) sealing said package with an easily openable closure, 15 c) heating the nutrient preparation in said package to a holding temperature of pasteurization in the range of about 70 ° C below the softening temperature of the plastic, 20 d) keeping the nutrient preparation in said pasteurization holding temperature in said pasteurization holding medium e) cooling to provide a nutrient preparation in an easily openable brush wrapper package that is manually openable to form a spout * 25, said nutrient preparation being free of k the vacuum state associated with the web filling.

Liquid nutrient preparations to which the method of the invention can be applied include non-carbonated fruit preparations, for example citrus fruit preparations or citrus-flavored preparations, fruit preparations. teas, vegetable juices and mixtures of vegetable juices referred to above.

Carbonation must be avoided, as otherwise the pressures that may develop during processing would be too high.

35 Another requirement for a nutrient preparation is that it be free from disease-causing and thermophilic bacteria. Most juices and beverages have a pH in the range of 2.8 to 4.0 and not above a pH of 4.6. At pH values above 4.6 teaspoon 5,96915, a potential problem is disease-causing bacteria. Below pH 4.6, problems include yeast, molds and bacteria.

5 If the pH is above 4.6, which includes products such as milk, the pre-treatment step should include treatment at a very high temperature, 115 ° C to 127 ° C, for 15 to 20 seconds to kill disease-causing bacteria, followed by cooling to ambient temperature. Preparative treatment at very high temperatures is recommended for some plant-based products, such as tomatoes, due to the initially high content of thermophilic molds.

Juices and beverages to which this method is applicable are prepared in 15 containers at ambient temperature in the range of 4 ° C to 24 ° C and pretreated as described above, if necessary. They are then pumped to a filling station where the juice or beverage is fed into the packages.

Although not essential, it may be useful to provide the piping between the tank and the filling station with a gasification valve. A gasification valve is used to add up to 0.7 kPa and most preferably about 0.07 kPa of nitrogen or carbon dioxide to the formulation. The purpose of gasification is to provide a slight overpressure to prevent bacteria from penetrating the package after filling. Carbon dioxide is recommended for this purpose • 25. A carbon dioxide gasified preparation contains such a small amount of carbon dioxide that it is not classified as a carbonated preparation.

At the filling station, which is of the conventional type, several individual packages are filled cold. The temperature of the liquid nutrient preparation. should be lower than about 27 ° C and preferably less than 21 ° C in order to develop a neutral pressure or a slight overpressure after filling. This can be compared to hot filling temperatures of the order of 80 ° C. The maximum temperature that can be used depends on the conditions 35, including the overpressure from any gasification gas and the strength of the sealing joint, which in some cases allows a small vacuum. However, as shown above, the vacuum is unavoidable. After filling and closing the cans, they should be at neutral pressure or slightly overpressured.

The most preferred packages are cardboard brush wrapping cans with a barrier layer inside the can, for example a foil and a polyethylene layer, and a second polyethylene layer to bind the foil to the cardboard. The outer surface of the can can also be coated with polyethylene, giving a total of five layers. The sixth layer, which is common in hot-fill methods, is not required. It is not necessary to use a strong closure, and therefore an easily openable brush cover package that can be opened to form a spout is suitable for use. Although some of the main advantages of the invention are achieved with an easily openable brush wrapper package, other types of packages, for example plastic bags or plastic bottles, may be used in accordance with the present invention, with its 15 objects being most broadly defined. Suitable plastics for packaging include vinyl resins, for example polyvinyl chloride, regenerated cellulose, polypropylene, polyethylene terephthalate, polycarbonates and other plastics used for nutrients. Where a barrier layer is to be used, ethyl vinyl alcohol or other similar barrier filler may replace the foil.

The cold-filled cans are transferred to a processing line with three zones, a preheating zone, a holding zone, and a cooling zone.

• 25 The processing line may be in the form of a continuously moving belt on which the rows of cans are placed. The cans are spaced apart so that water can flow down the sides of the cans to heat or cool the contents.

30 1. Preheating heatsink

Cans filled cold in the preheating zone are most preferably preheated by lowering the water at a temperature of 82 ° C to 85 ° C onto the cans and allowing it to fall down the sides. After a period of time, which varies depending on the size of the can and the liquid preparation therein, it reaches the desired "holding temperature" of pasteurization. The recommended "holding temperature" for pasteurization is about 75 ° C, which is reached about 13 to 7,96915 in 19 minutes for 1 liter cans. Two-liter cans take 20-24 minutes to reach this temperature, while 4-7 minutes is enough for 250 ml cans.

5 2, Pitovvöhvke

In the holding zone, the preparation is kept at the required pasteurization temperature for a predetermined time to ensure that all microorganisms are properly destroyed. A suitable time for the various "holding temperature-10 parasites" of pasteurization can be found in the basic literature in the field. At the recommended holding temperature of 75 ° C, a holding time of ten minutes is recommended. The temperature should not be higher than 79 ° C, where the time is about 4 minutes, otherwise there may be problems with the softening of the plastic when the package is polyethylene, or the release of the foil layer from the cardboard. Slightly higher temperatures can be used for plastics with a higher softening temperature, such as polypropylene. At lower temperatures, the holding time is quite long. For example, at 71 ° C it would be about 25 minutes.

20 3, Cooling belt

After keeping the cans at the required holding temperature for the required time, they go into the cooling zone and come out at a temperature of about 32 ° C to 40 eC. This temperature is desirable because it quickly evaporates * 25 off the excess moisture that has adhered to the packaging.

The temperature of the cooling water can be about 2 ° C to 16 ° C. The cans then leave the processing line and are packed in boxes.

The invention is further illustrated by the following examples:

Example I

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The first example relates to the production of a batch of 4546 liters of orange juice of normal strength (ready to drink). 614 liters of orange -35 juice concentrate with a strength of 65 brix (per cent soluble solids) are added to 3932 liters of water and mixed for »10 minutes. It is then pumped using a pressure-driven pump through 8,96915 pipes to the filling device. The pipes include a gasification valve for blowing carbon dioxide to obtain a final product with a gas pressure of about 0.7 kPa. In the filling device, the preparation is filled at a temperature of about 21 ° C into one-liter brush cans, which are heat-sealed by pressing. The temperature of the cans is raised to 75 ° C in IA minute and kept at this temperature for ten minutes. They are then cooled with water at 4 ° C for 12 minutes to obtain a temperature of 32 eC at the outlet. The recommended shelf life of orange juice is three months and the recommended maximum is six months. The taste of the orange juice is considerably better than the taste of the orange juice produced by the hot-filling method.

Example II

15 This example relates to Caesar's clam mixture. A batch of 4546 liters is made from 455 liters of tomato paste (32-34 brix), 254 kilograms of salt, 27 kilograms of monosodium glutamate, 317 kilograms of solid glucose, 13.5 kilograms of spices and 45.5 liters of mussel broth. It is pumped into a pasteurizer where the temperature of the preparation is raised to 121 eC in about 1020 seconds and maintained at this temperature for 48-52 seconds, then cooled to 21 eC and then filled and treated as described in the first example.

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II

Claims (16)

A method of providing liquid food products which are shelf-resistant, characterized in that it comprises the following steps: (b) closing said package with a readily openable closure; (c) heating the food product in said package to a paste pouring pouring temperature within the range of from about 70 ° C to a temperature below the plasticization temperature of the plastic; d) maintaining e) cooling to obtain the food product in a readily openable wrapper with ash, which package can be manually opened to form a pouring beak and which food product is free from vacuum. the state that connected gets to the hot filling. ; 25 Process according to Claim 1, characterized in that the process uses fruit products and vegetable juices as the liquid food product. 30 Method according to claim 2, characterized in that it uses orange juice as the liquid food product in the process and that the pasteurization pouring temperature is maintained in the range 71 ° C - 79 ° C. 35 Method according to claim 2, characterized in that the method uses a mussel tomato product as the liquid; food product. Il 13 96915 5. A method according to claims 1, 2 or 3, characterized in that when the plastic or plastic coating of the package is polyethylene, the pasteurization pouring temperature is maintained in the range 71 ° C - 79 ° C. 5 Process according to claim 2, characterized in that the liquid food product is poured substantially free from artificial preservatives. 10 Process according to claim 6, characterized in that the liquid food product is stored for at least three months. Method according to claims 1, 2 or 3, characterized in that the cold loading is carried out at a temperature below 27 ° C. 9. A method according to claims 1, 2 or 3, characterized in that the pasteurization pouring temperature is maintained at a temperature of about 75 ° C. 20 10. A process according to claims 1, 2 or 3, characterized in that the pasteurization pouring temperature is maintained at a temperature of about 75 ° C and that the liquid food product is poured at this temperature for about 10 minutes. Il 25 Method according to claims 1, 2 or 3, characterized in that the cooling after pasteurization is carried out to a temperature of about 32 ° C - 40 ° C. 30 Process according to claim 7, characterized in that the process uses citrus juice as the liquid food product. 13. A method according to claim 1, characterized in that the cold loading is carried out at ambient atmospheric conditions. 35 14. A method according to claims 1, 2 or 3, characterized in that it comprises a preparatory stage in which the preparation 14 96915 is subjected to a very high temperature heat treatment to destroy any possible pathogenic and thermophilic microorganisms following cooling. 5 15. A process according to claim 1, characterized in that the process uses a liquid food product whose pH value is in the range 3.0 to 4.6. Process according to claim 1, characterized in that the process uses a liquid food product which is non-alcoholic or containing only a small amount of alcohol. 1 II ·