Cellulose-based corrugated sleeved casing for food products

FIELD: cellulose-based sleeved casing for food products.

SUBSTANCE: corrugated sleeved casing is manufactured by method including preparing cellulose solution with the use of solvent such as N-methyl-morpholine-N-oxide. Corrugated sleeved casing is especially stable and is therefore suitable for fully automatic stuffing apparatuses of the type employed for producing of sausages cooked in water or bouillon.

EFFECT: improved strength and provision for using such casing in fully automatic food processing systems.

12 cl, 2 dwg

The invention relates to a shirred tubular casing for food products based on cellulose. It is particularly suitable for the manufacture of sausages.

Wrappers for food products, in particular sausage casings are offered in this form, when approximately every 15-50 m shell compressed corrugated tube length of about 20-60 see Shirring of artificial casings known for a long time and repeatedly described in the literature of a General nature, and also in the patent literature (for example, in the monograph: G. Effenberger. Wursthullen - Kunstdann. H. Hoizmann Verlag GmbH & Co. KG, Bad Worishofen, 2. Aufl. [1991] S.58-60). It is on the so-called hariraya machines. Before crimping the shell is flattened and wound. Then she unwound from the reel, is inflated and stretched on a mandrel hariraya machine. While the outer diameter gamerules mandrel defines an inner diameter of the obtained corrugated tube. Shirring has a large load on the shell. Therefore, immediately before shirring or during it, to make it more supple, it is irrigated or wetted inside, outside or both sides with water and/or oil. This prevents the formation of cracks in the folds of the corrugated tube. The tools themselves fluting can be made completely different designs. And the known, for example, gavriloaie wheel, outside which can be smooth or jagged, and the moving tape. After embossing the desired number of meters sheath clipped. Made so the corrugated tube should be as formoustojchivy and self-sufficient. However, for storage and transportation facilities often provide the outer packaging /usually mesh or foil/. Finally, also known shell, gavriloaie on formoustojchivy the sleeve. When stuffing sausage meat corrugated tube is compressed. Often corrugated tubes are placed in the store device, from which alone they are automatically removed and fixed to the advancement of high speed packing machines. Moreover, it is extremely important that the corrugated tube is not broken, including when it is in a flooded condition. Otherwise, the process is broken that needs to be restored with great difficulty and manually.

Required portioning sausages after stuffing, and end the blockage or twisting of the sausage is usually performed automatically. Thus, in particular, are made sausages. This portioning of meat for sausages is the pump stuffing machine. At each pause in the movement of the conveyor path p is reclusive shell is formed corresponding to the length of the sausages. The whole process is fully automated and runs with great speed. The bundle is made thus sausages suspended is also mechanically on a corresponding frame, on which the sausages are then directly served by other types of processing. In such a boiled sausage casing, used for stuffing and manufacturing, after cooking, and possibly smoked and cooling sausages, before packing in bags, glass or metal cans, mechanically removed.

The manufacture of the bag wrappers for food products based on cellulose up to the present time were mostly viscose method. Under pressure through a nozzle with an annular slit and extruded solution xanthogenate cellulose (= viscose). Then in different precipitation and washing baths is the regeneration of cellulose from viscose. First the precipitation bath is typically an aqueous solution of sodium sulfate and sulfuric acid (so-called bath Muller). For deposition are also used bath of an aqueous solution of ammonium sulfate, sodium sulfate and sulfuric acid. Then the sleeve of regenerated cellulose washed, can be treated by the plasticizer (for example, glycerin) by impregnation from the inside and/or outside (for example, for easier separation) is dried to obtain a given eye the final moisture and leaves the roll. Then the rolled material, as already mentioned, can gamerbase segments. The mechanical strength of the corrugated tubing, non-irrigated and irrigated, bag of cellulose membranes, obtained by the viscose method leaves much to be desired.

Therefore, before the invention of the task was to improve the mechanical stability of the corrugated tubes of tubular cellulosic casings. The problem is solved in that the fluting used cellulose casings, made of viscose method, and a method using N-Methyl-morpholine-N-oxide (NMMO) as solvent of cellulose.

The object of the invention is according to the corrugated tube of the tubular casing for food products based on cellulose, characterized in that the shell is made by a method using N-Methyl-morpholine-N-oxide (NMMO) as solvent of cellulose has an arithmetic mean roughness value R_adetermined according to German standard DIN 4768, in the range from 5 to 14 nm, and is closed at one end by twisting and sealing twisted into a corrugated tube or by deformation last mm corrugated tube by means of a shock bolt with simultaneous sealing of the deformed area inside corrugated is logging.

Preferably the shell (not the form) has a nominal caliber from 14 to 50 mm, preferably from 16 to 25 mm In this case, it is particularly suitable for use as a detachable shell, in particular in the manufacture of sausages. One corrugated tube includes approximately 30-70 m, preferably about 40-60 m shell.

It is known (WO 97/31970) the manufacture of the bag (not) cellulose casings way using NMO as a solvent of cellulose. This uses the fact that cellulose is soluble oxides of tertiary amines with no chemical changes, i.e. without derivatization. N-methyl-morpholine-N-oxide (hereinafter called NMMO) proved to be particularly appropriate tertiary amine oxide. A great advantage of this method is that technically it is less costly and less environmentally harmful (in particular, it is possible to refuse necessary for the viscose method of hydrogen sulfide). For the manufacture of a solution of cellulose fiber (e.g., wood or cotton) is treated at room temperature in 60 wt.%-"a solution of N-Methyl-morpholine-N-oxide, with constant stirring. With increasing temperature and decreasing pressure water is diverted up until in the sediment only cellulose and monohydrate, NMMO. In this case, the solvent is 87.7 m is S.% from NMMO and the remainder is water. Cellulose dissolves in him completely at a temperature of about 90-105°C. Stirring and heating under reduced pressure further diversion of water, so that in forming the solution, the solvent of cellulose consists of 90,5-of 92.5 wt.% NMMO and 9.5-7.5 wt.% water. The proportion of the cellulose is from 6 to 15 wt.% from the total mass of the molding solution. Another advantage of the method using NMMO is that the length of the cellulose chains remains practically unchanged (degree of polymerization average usually amounts to 400-650). In contrast, in the viscose method, there is a noticeable degradation of the chains. To secure the special properties of the shell may be appropriate mixture forming solution with other components. Suitable synthetic polymers or copolymers, and sucrose esters. They act primarily as permanent ("primary") plasticizers. In addition, they reduce the tendency of the pulp to crystallization. The share of these additional components may comprise up to 25 wt.% by weight of dry pulp. Usually the proportion of these components is not more than from about 1 to 20 wt.%.

Then a solution of NMMO and pulp extruded downward through the annular nozzle (molded). The molding temperature of the solution in the annular nozzle is preferably from about 85 to 105°C. an Annular school the ü is usually from 0.1 to 2.0 mm, preferably 0,2-2,0 mm While the width should correspond to the "hood" (private on the speed of extrusion and the speed).

After this is obtained by extrusion of the primary sleeve is stretched in the transverse direction in the area between the annular nozzle and the surface sediment of the bath, where it passes through the air. This plot, in which the moulding is preferably 1-50 cm, and particularly preferably from 2.5 to 20 see It also depends on the diameter (caliber) of the tubular film after molding blown. The moulding is carried out with compressed air or under an appropriate pressure gas through the holes in the body of the jet come inside sleeves. Due to the stretching in the transverse direction substantially increases the transverse strength of the sleeve. After logging in molding the tub through the appropriate device in the body of the nozzle forming solution bath is also added inside the paper sleeve. It quickly hardens sleeve and simultaneously prevents sticking of the inner sides of the sleeves.

Forming bath is an aqueous solution containing NMMO. This solution includes about 10 to 20 wt.% NMMO. In quantitative terms, NMMO can be practically recovered from the precipitation bath and used povtorilas aqueous solutions of NMMO clean, for example, ion-exchange columns. Water can in this case be drained under vacuum until such time as the concentration of NMMO reaches 60 wt.%. This solution, NMO may again be used for the manufacture of moulding solution.

For further hardening, it is advisable to handle the flattened sleeve in several containing NMMO precipitation barkah. If the precipitation sludge content of NMMO is still about 10-20 wt.%, in subsequent barkah it decreases. From barge to barge temperature increases and at last the barge reaches about 70-80°C. To the precipitation area generally adjacent with warm water up to 40-60°Barki, which washed away the last traces of NMMO of the sleeve. After this can be added the so-called plasticizing Barca. It is an aqueous solution of a plasticizer for cellulose. Suited especially polyole and polyglycols and especially glycerol. The aqueous solution usually contains from about 5 to 30 wt.%, preferably 6-15 wt.% plasticizer or mixture of plasticizers. The temperature in the plasticizing Barka is usually between 20 and 80°C, preferably between 30 and 70°C. thereafter, a sleeve in an inflated condition served on the dryer, if this proved to be particularly suitable dryer with hot air. It is advisable to perform drying at UBA the surrounding temperature (from about 150° From the entrance to about 80°on dryer). When drying the amount of swelling is reduced by 130-180%, preferably 140-170%, depending on the drying conditions and the amount of glycerin. Preferably drying the sleeve is inflated to the original caliber to maintain constant obtained the degree of transverse orientation.

After passing through the dryer hose again moistened with a water content of from 8 to 20 wt.%, preferably 16-18 wt.%, calculated on the total weight of the sleeve. Then by using a pair of flatting rollers it can be flattened and hit the road in a roll. In accordance with the prescribed use of the shell may also be impregnated or coated with internal and/or external parties, such as impregnation smoke liquid dressing to further enhance the stability of the corrugated tubes or internal processing composition for best separation of the shell.

To improve slip corrugated tubing on the legs, as well as to ensure later, you can uninstall the shell, excluding damage formed on the sausages own skin, proved to be expedient to provide the shell with the inner sides of the impregnation or coating. This impregnation or coating may be performed before the drying process or during shirring through gamerules Dorn. Famous is, for example, coating a water-soluble cellulose ethers (US-A 3898348), mixtures of lecithin and alginate, chitosan and/or casein (EP-A 502431 = US-A 5358784), mixtures of anionic and nonionic water-soluble cellulose ethers and means to improve slip (EP-A 180207) or mixtures of lecithin and polytetrafluoroethylene (EP-A 635213).

Compressed in the corrugated tube, the shell must already have at one end the blockage to stuffing the product does not fall on the padded table and would not soil the following chain of sausages. The blockage must be done in such a way that prevented loss sausage stuffing, and an air outlet, because otherwise the inside will be unbalanced pressure. When using an additional, separate capsules of materials, such as clips or staples from plastic or metal, there is always the danger that they will get along with the minced meat into the sausage. Therefore, the preferred corking spin or knots of the sheath material (DE-1297508, DE-1532029, DE-2317867, EP-A 129100).

Often limit the obstruction is such that special forceps inside extracted a small piece of a corrugated tube and after a short twist again stalkivaetsja inside. Another possibility is that by means of a shock bolts are deformed few days the wifi mm corrugated tube and simultaneously stalkivajutsja inside her.

Shirring is made by way of using NMMO cellulose casing is made known to the specialist way. The above-described effect of the improved preservation stability of the corrugated tube does not depend on a particular method of shirring. Adequate methods corrugation described, for example, in DE-1268011, DE-B 1632137, DE-1632139, DE-a 2231144, DE-a 2231145 and DE-a 2236600.

Upon closer examination it was revealed that its structure and properties, making this method cellulose membranes differ from the known present in membranes of regenerated cellulose.

However, what was unexpected was these differences are clearly visible already in the corrugated tubes of the shell.

To explain the differences in corrugated tubes was studied the surface structure of membranes. It was found that there is a significant difference. So, is made by way of using NMMO shells have a much smoother surface than is made of viscose method. Can clearly see the difference in images obtained raster microscope power lines (Atomic force microscope, AFM).

Figure 1 represents a snapshot sleeve surface of regenerated cellulose in flooded condition, made of viscose method (using a precipitation bath of sodium sulfate and sulfuric acid), the X-Axis and divided into segments of 20 μm, and the Z axis, in turn, into sections of 500 nm (+0.5 µm), as in figure 2. Therefore, the relief is increasing. The interval between the highest and lowest points on the surface is more than 1000 nm.

Figure 2 is an AFM image of the surface of the sleeve of regenerated cellulose in flooded condition, made by way of using NMMO. The surface is almost smooth. Visible only certain elevation. The interval between the highest and lowest points on the surface is clearly less than 500 nm.

If the viscose method instead of a bath Muller to use aqueous precipitation bath ammonium sulfate - sodium sulfate - sulfuric acid, the surface roughness is increased further. Made by this variant of the method of the shell (obtained, for example, on the company Trivial, Brazil) during the shirring are particularly low mechanical stability. Corrugated tubes are broken when the load weight 340 g or higher. Corrugated tube of cellulose membranes, obtained by the viscose method using baths Muller as a precipitation bath, have a tensile strength ranging from 600 to about 1100 Corrugated same tube according to the invention in the same way corrugation can withstand before they come up to 1600, usually 1200-1500 g (measurement method for determination of strength p is sriv see in example 1). Higher stability corrugated tubes according to the invention presumably can be explained much more smooth surface of the shell, which allows you to firmly connect the folds of the corrugated tube.

For made by way of using NMMO shells arithmetic mean roughness value R_adetermined according to German standard DIN 4768, is in the range from about 5 to 14 nm, and made of viscose method in the range from 70 to 140 nm.

In addition, photos taken by a light microscope, show that the resulting method using NMMO membranes are membranes made of regenerated cellulose with a substantially higher density. This leads to increased strength of shells or allows you to have thinner walls while maintaining the same strength.

Finally, a smoother surface also leads to the fact that the shell easier to remove. Therefore, can be reduced by applying a composition for better subsequent separation applied to the inside of the shell, or even abandon it.

In conclusion, as determined by electrokinetic potential (Zeta-potential) of the shell. This value describes the relationship of the load on the boundary surface between the membrane and the liquid phase. This allows the SDE is the substance of the conclusions on the status and properties of the surface. In addition, it gives information about how affects the surface of the electrolyte and pH. In aquatic environments, there is the electrification of the surface of the membrane, caused by the dissociation of functional groups of the polymers on the membrane surface or specific adsorption of ions from solution of the electrolyte. Arising in connection with this, the polarity of the polymeric material causes the formation of electrical double layer. The potential of this electric double layer cannot be measured directly. Therefore, to characterize the electrical properties involved Zeta-potential. Potential occurs when the tangential movement relative to each other the membrane surface, including dissociable group, and the electrolyte solution. This corresponds to the density of the net surface charge of the membrane. Equation Helmholtz-Smoluchowskiego describes the Zeta-potential as follows:

where ζ - Zeta-potential [V],

E_s- potential currents [V],

K - conductivity [ Ω^-1·cm^-1],

η - dynamic viscosity [PA·C]

∈_about- constant effects [·V^-1·cm^-1],

ΔP - pressure drop [PA],

D is the dielectric constant.

For manufactured by the method of NMMO cellulose casing Zeta-potential is l was in the range of pH from 6 to 10.5 from about -5 to -25 mV. In the pH range from 3.5 to 5.5 it was approximately from +18 to -15 mV.

Corrugated tube according to the invention is particularly suitable for use on high-speed packing machines. Interruptions in the production process mentioned above in connection with the gap corrugated tubes, thus no longer happen. Corrugated tube can easily be straightened on the legs and filled with sausage meat. Particularly suitable corrugated tube according to the invention in the manufacture of cooked sausages, especially sausages and wieners. The shell is removed from the frankfurters and wieners in a known manner after cooking broth for automatic devices for removal of the shell.

The examples given below serve to explain the invention. Unless otherwise stated, the percentages denote percentages by weight.

EXAMPLE 1

Gel cellulose sleeve caliber 18 mm was manufactured by the method of aminoacid and plasticized by glycerol. Immediately before drying in a drying tunnel sleeve was soaked with a solution of

1.0% carboxymethylcellulose

1,0% sorbitan-trioleate

0.5% of a mixture of mono - and diglycerides and

97.5% of water

according to the method, known as "bubble coating. Impregnation facilitates later removal process of the shell. Before entering into the drying channel is a pair of flatting rollers, which remove from Isny impregnating solution.

In the dryer hose in an inflated state is first dried to a moisture content of from 7%to 8%, and then irrigated with water to a moisture content of 16-18% and leaves. Exposure is carried out in the chamber conditioning. Subsequent shirring sleeve unwound from the reel and molded pieces, approximately 50 m in length each, the known method of shirring to obtain a corrugated tube length of about 40 cm with the application of paraffin oil. Corrugated tube took a load in 1500

Produced determination of tensile strength so that the corrugated tube was placed horizontally, and a segment with a length of 15 cm was left without support. In the middle of this section was then placed wire gauge wire diameter about 2 mm), which loaded more weight up until the tube was not breaking. Was measured, which can withstand the weight of the corrugated tube. This measurement method was also used in the other examples.

In the next step, the corrugated tube supplied with end caps. To do this separately corrugated tube is inserted into a fixture of the appropriate form, and the last fold after mechanical deformation pressed into the tube. Then corrugated tube, Packed in foil, Packed in a cardboard box. Foil pack b is La made so what consumer corrugated tube could be removed from the foil without fear of rupture and placed in the store the automatic stuffing machine.

EXAMPLE 2

Was repeated in example 1 with the difference that instead of the solution described there, contributing to the rapid destruction of the shell, used the drug liquid smoke:

38% acidic liquid smoke (Enviro 24 R, Red Arrow, Manitowoc, Wisconsin),

1% of lecithin,

1% of the chrome complex of the fatty acid series (Montacell),

10% glycerol and

50% water.

Made thus impregnation led to the rapid destruction of the shell and at the same time allowed the smoke flavoring to move on the surface of the sausage meat. Corrugated pipe broke under load in 1420,

EXAMPLE 3

Gel cellulose sleeve was manufactured according to example 1, but this time without the internal impregnation. The membrane was dried to a residual moisture content of from about 8 to 10%.

After exposure in the camera conditioning sleeve was removed from the reel and Gavrilova. Through gomeroi Dorn inner side of the shell was watered with an aqueous solution of:

10% lecithin,

33,0% propane-1,2-diol,

0.4% polyoxyethylene-sorbitan-monooleate (Tween 80),

0.2% polyethylene glycol-monoacrylate (Genapol × 80)

(BUT-[CH₂-CH₂-O]_n-[CH₂]_m-CH₃, with an average of n= and m=12),

12,5% dispersion of silicone oil,

3,0% protein wheat (Amypro SWP),

2.5% dispersion of polytetrafluoroethylene and

38.4% of water.

The composition was selected so that when the desired concentration of active substances on the surface of the corrugated tube has acquired the humidity from 16 to 18%. The following stages - terminal blockage and packaging was carried out as in example 1. Corrugated tube took a load in 1350,

EXAMPLE 4

Was repeated example 3 with the difference that instead of the described composition there was dispergirovanija solution of 37.7% of liquid smoke (Zesti Smoke Code 10),

4,3% NaOH,

1.8 alginate,

10.1% of lecithin,

3,0% Genepol, and

43.1% of water.

Impregnation provided together with the effect of light subsequent removal of the shell is also the dressing of the smoke flavoring. Corrugated tube loaded weight at 1250

1. Corrugated tube from a tubular wrapper for food products based on cellulose, characterized in that the shell is manufactured by a process in which the solvent for preparation of a solution of cellulose is N-methyl-morpholine-N-oxide, has an arithmetic mean roughness value R_adetermined according to German standard DIN 4768, in the range of 5-14 nm and sealed at one end by twisting and zataskivanija twisted into a corrugated tube or deformation the last millimeters tube shock bolt and simultaneous zataskivanija deformed section inside a corrugated tube.

2. Corrugated tube according to claim 1, characterized in that the membrane is stretched in the transverse direction for air ventilation between the annular nozzle and the molding surface of the bath by blow molding.

3. Corrugated tube according to claim 1 or 2, characterized in that the cellulose has an average degree of polymerization of 300 to 700, preferably amounts to 400-650.

4. Corrugated tube according to claim 1, characterized in that the shell contains up to 25% by weight of the cellulose of other high molecular weight, weakly polar compounds.

5. Corrugated tube according to claim 4, characterized in that another high molecular weight, weakly polar compound is a synthetic polymer or copolymer.

6. Corrugated tube according to claim 1, characterized in that the membrane has a nominal caliber 14-50 mm, preferably 16-25 mm

7. Corrugated tube according to claim 1, characterized in that it includes about 30-70 m, preferably about 40-60 m shell.

8. Corrugated tube according to claim 1, characterized in that the shell contains 8-20 wt.%, preferably 16-18 wt.% water.

9. Corrugated tube according to claim 1, characterized in that the shell contains a plasticizer, preferably glycerol.

10. Corrugated tube according to claim 1, characterized in that the shell with the outer and/or inner side provided with impregnation or coating.

11. Corrugated tube according to claim 1, distinguished by the lasting themes what electrokinetic potential in the pH range 6-10,5 is about (-5)-(-25) mV, and the pH range of 3.5-5.5 to about (+18)-(-15) mV.

12. Corrugated tube according to claim 1, characterized in that it is suitable for the manufacture of the cushioning device, boiled in water or broth sausages, preferably for the manufacture of sausages.