PT98045B - METHOD FOR THE MANUFACTURE OF PIPES FOR THE PACKAGING OF FOOD PRODUCTS AND PIPES SO OBTAINED - Google Patents

Abstract

The invention relates to a tube for packaging food products (for example, sausage casing), the principal advantage of which lies in the combination of properties achieved on account of its lightweight structure, i.e. improved possibilities for additional processing, rapid processing of sausages to be matured in the tube and the properties of high thermal resistibility provided by the nature of the tube compared with collagen tubes, and greater elasticity of the tube according to the invention when compared with conventional fibrous tubes. This combination of properties provides a wide area of applicability and supplies the basis for a considerably higher productivity rate, both in terms of the production of tubes and in the meat-processing industry. The invention is characterized by the fact that use is made, in the tube-production process, of lighter long-fibre material than in the prior art.

Description

The invention relates to a lightweight tube and a method for its manufacture composed mainly of long-fiber material and regenerated cellulose, used to wrap food products, as in the manufacture of sausages. In terms of its elastic properties, the said tube corresponds to the collagen tube, but it is superior to this in terms of its resistance and thermal resistivity.

Food wrappers are used to pack various types of meat, sausages and other food products. The basic material used in the production of wrapping materials is cellulose (cellophane, regenerated cellulose, cellulose hydrate), cellulose derivatives, such as cellulose ether, proteins, collagens and other screens, films or polymeric laminates, natural or synthetic, comprising combinations of these.

The properties of tubes made of collagens, as well as tubes made of cellophane, are inadequate due to their lack of resistance and their low thermal resistivity during the sausage production process. Collagen tubes, for example, crack at temperatures of 80 ° C. Collagen and cellulose tubes are always heavier than tubes reinforced with corresponding fibers. Despite the weight of the walls of collagen and cellulose tubes, the diameter values of the tubes produced vary. Due to these reasons, the productivity of sausage production is low.

Another practice is to use fiber-reinforced cellulose wrappers, canvas made from paper and / or rice paper (such as asclepias) using blackberry, or other naturally occurring fibers, such as hemp (for example, abaca or hemp). manila), flax fibers, or synthetic fibers (for example polyamide, polyether fibers

and polyacrylonitrile), and even mixing said fibers. The papermaking process to be used in the aforementioned tube material, such as manila-based paper, has been described in US Patent Publications No. 3,433,663 and 3,135,613, for example. The impediments to the use of cellulose tubes reinforced with known fibers are the high price and the inelasticity of the tube, resulting from its structure. Due to these reasons, the productivity area of this pipe material is limited. They cannot, for example, be used to replace collagen tubes.

A tube produced in accordance with this invention represents a decisive improvement over the aforementioned disadvantages. In order to carry out this improvement, the production method used to produce the fiber-reinforced cellulose tubes according to this invention, for the packaging of food products, is characterized by what is stated in claim 1 and, as for the tube, by which is stated in the characteristic part of claim 4.

The unique advantage of this invention is the combination of properties achieved by the light structure; that is, the excellent possibilities for further processing and the property of high thermal resistivity facilitated by the tube, in comparison with collagen tubes, together with excellent properties of resistance and superior elasticity of the tubes, when compared to conventional fibrous cellulose tubes. This combination of properties means a wide area of applicability and shape based on considerably higher productivity, both in the production of tubes and in the meat processing industry.

Although elasticity is generally

considered an advantage of collagen tubes, it was observed that the lighter fiber reinforcement according to this invention results in a resistance almost equivalent to the heavier fiber reinforcement previously used, but still in an elasticity not only of the same class as the tube collagen, but that exceeds it. The fineness resulting from the loss of paper weight mainly based on manila hemp. allows viscose to better penetrate the matrix between the fibers. This, in turn, leads to the formation of a strong composite material between viscose cellulose and manila hemp, which also provides a smoother inner surface in the tube. It has also been observed that the curing process of salami packed in tubes according to this invention is accelerated.

Hose-shaped tubes, in which the aforementioned screens are used, can be produced by applying methods and devices well known to those skilled in the art. These methods have been described in US Patent Publication No. 2,144,899, while the devices cited are described in No. 2,105,273, for example.

In the following, although the invention is explained with reference to examples, they are not intended to limit the invention, but to present and provide the basis for the inventive idea.

Viscose produced in a known manner was necessary for the production of the tubes. During the production of viscose, wood cellulose with a high alpha-cellulose content was treated with bleach to produce alkaline cellulose. After a controlled aging of the alkaline cellulose, carbon disulfide was mixed in the compressed and fragmented mass. The result of the reaction was

cellulose xanthogenate, which was then dissolved in bleach, which resulted in viscose.

To produce fiber-reinforced tubes, paper composed mainly of manila hemp and unwound from a roll was folded to form a tube. Next, the tube was impregnated using viscose applied by a nozzle in the manner mentioned above.

Immediately after that, the tube was immersed in a bath of salt / sulfuric acid, while also treating the inside of the tube with the same mixture of salt / sulfuric acid, which caused the viscose to coagulate and regenerate into cellulose. . The tube, which for the most part was flattened, was then directed to a water bath and then a heated glycerin bath. Finally, the tube passed through press rolls, to be dried inside a drying channel, where air was blown into the tube, and the tube was then wound up. According to this invention, the weight of the paper produced mainly with manila hemp has been tested and shown to be around 13 g / m within a tolerance of 1 g / m 2. The weight of the paper is given as air dry weight , after keeping the paper for four hours at a temperature of 25 ° C, with a relative humidity of 20%, to reach equilibrium conditions after removing the test specimen from its storage packaging. It was noted that the consumption of viscose was reduced in the production of tubes reinforced with this material.

The values presented in the table are used to compare the elasticity and burst resistance properties of the Visko Light tube according to this invention, the weight of dry manila hemp paper being air in the air of 13 g / m 2, with a tolerance 1 g / m 2 with the corresponding properties of the

collagen and heavier tubes. The size of the tube is expressed as commercial size, which is the diameter of the tube before it is filled. It should be noted that the previous practice was to use long-fiber material, the weight of which varied according to the diameter.

The elasticity of the tube is defined as the amount of stretch per unit of pressure, when filled in the wet state, after soaking for 30 minutes in water at 20 ° C. These values are computed as follows.

Visko Light, size 65:

Tube diameter, 67.7 mm at a filling pressure of 15 kPa;

Tube diameter, 73.3 mm at a filling pressure of 50 kPa;

which results in

Elasticity = (73.3 - 67.7) / (50 - 15) = 0.16 mm / kPa.

The resistance to the snatching of the tube was determined in the wet state mentioned above and the values exposed in tubular form.

The strength and elasticity properties were determined at a temperature of about 20 ° C, immediately after removing the tube from the water used for soaking. The weight determinations of the tube were carried out under current laboratory conditions, with air

dry and without raising the temperature. Oven drying was not used.

The data thus obtained confirm the excellent elasticity properties of Visko Light tubes compared to tubes reinforced with heavier fibers and collagen, which until now has been considered to offer the best combination of elasticity with respect to diameter stability. The values presented in the table indicate that Visko Light tubes are proof of equivalence of Visko Light tubes, in terms of elasticity under pressure, to collagen, and even higher than collagen. In relation to the resistance to snatching, Visko Light tubes proved to be superior to collagen and only slightly weaker than a conventional tube, composed of heavier fibrous material. Due to its fineness, the quality of Visko Light tube that can be pleated or furrowed to form a drop or stump is greater than that of heavier tubes previously used.

When compared to collagen, for example, a stump of Visko Light contains twice as much tube as a stump of collagen of equal length.

TABLE

Paper weight

Product Tama- son mm hemp from manila g / m 2 Visko 35 13 Light 50 13 65 13 80 13 90 13 10 5 13

Weight in pipe g / m 2 Resistance ^to bentamen- kPa arre- Elasti City mm / kP 1.4 132 0, 08 0.0 92 0.10 1.9 74 0.16 1.2 65 0.22 2.7 59 0.25 2.9 55 0.31

TABLE (Cont.)

Product Tama- son mm Paper weight hemp from manila g / m 2 Weight in pipe g / m 2 Resistance when they burst kPa Elasti City mm / kP Tube of 35 17 0.2 147 0, 06 Material 50 17 1.0 10 5 0, 08 Fiber 65 19 1.5 93 0.11 Heavy 80 21 2.2 86 0.14 90 21 2.3 79 0.16 10 5 23 30 4 75 0.21 Tube of 47 110 73 0.10 Collagen 55 136 80 0.11 65 20 7 70 0.10 75 220 52 0.14 90 353 50 0.21 100 286 46 0, 20

Salami curing process was accelerated inside the Visko Light tubes. Empirically, the LÚbeck salami curing process, when placed inside a known 62 mm diameter heavier fiber tube, takes three weeks, which means that it loses 36% of its weight during the three weeks. When using a 70 mm diameter Visko Light tube, Lubeck salami takes three weeks to cure (36% reduction in mass) although the Visko Light tube contains about 25% more mass. The curing conditions were the same in both cases. Other examples based on the same 70 mm casing resulted in a Lubeck salami uniformly cured and dried after just three weeks of processing in a Visko Light casing, while the same product took a further week of processing to achieve the same uniformity in a fibrous wrapper of greater weight, with a concomitant greater loss of product weight.

The Bendtsen test used in the paper industry was used to determine the smoothness of the inner surface of the tube. The test gave Visko Light tube values of about 700-800 cm / 2 min on average, whereas the heavier tube used in the comparison had values that exceeded 1000 cm 2 / min on average.

It should be noted that the above invention has been described with reference to only two of its preferred embodiments. This should in no way limit the invention that will be described according to the scope of the inventive idea, as defined by the following patent claims.

Claims (4)

R Ε IV INDICATIONS: there. - Method for the manufacture of tubes for packaging of food products (for example sausage) composed mainly of a base material made of long-fiber manila hemp paper (finished) which, having been wet-strengthened by the use of cellulose regenerated, it is formed as a tube, impregnated with viscose, after which the impregnated material passes through one or more acid and / or salt treatment baths, coagulating the viscose during these treatments due to the effect of the acid and / or salts and being then regenerated in cellulose, so that the fibers are encrusted by the regenerated cellulose to form the tube, characterized by the fact that the manila hemp paper used has a dry air weight of a maximum of 15 g / m 2. 2nd. Method according to claim 1, characterized in that the used paper has an air dry weight of a maximum of 13 g / m 2, within a range of ± 1 g / m 2. 3rd. Method according to claim 1 or 2, characterized in that the diameter of the tube produced is less than or equal to about 165 mm. 41. - Tube to be used in the packaging of food products (for example, sausage wrapper) composed mainly of a base material made of long-fiber manila hemp paper, the material having been wet-strengthened by use regenerated cellulose, and regenerated cellulose, characterized -13 because the used long-fiber manila hemp paper has an air dry weight of a maximum of 15 g / m 2. 5th. _ Tube according to claim 4, characterized in that the used long-fiber manila hemp paper has a maximum dry air weight of 13 g / m 2, within a range of - 1 g / m 2.