JPH06313294A - Production of raw paper for fibrous casing - Google Patents

Abstract

PURPOSE:To provide a method for producing fibrous casing raw paper having good wet strength and alkali resistance and used for fibrous casings for packing meat products such as hams or sausages. CONSTITUTION:The characteristic of this method for producing raw paper for fibrous casings comprises impregnating or coating a sheet-like substrate comprising cellulose pulp with an aqueous solution containing chitosan or a chitosan salt and a water-proof agent in a chitosan concentration of 0.05-5.0wt.%, thus providing the raw material having a chitosan content of 0.5-15wt.% based on the paper substrate before absolutely dried, and having a waterproof agent content of 0.15-15wt.%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing fibrous casing base paper. More specifically, the present invention has good wet strength and alkali resistance (ie, strong resistance to alkaline liquids) and is used in fibrous casings for filling meat products such as ham and sausage. The present invention relates to a method for manufacturing a base paper for a casing.

[0002]

2. Description of the Related Art Processed meat products such as ham and sausages are manufactured by filling a tube-shaped casing with a kneaded product prepared by mixing raw materials and then subjecting it to heat treatment, sterilization treatment, smoke treatment and the like. There are natural casings and artificial casings (cellulose casings, collagen casings, plastic casings, fibrous casings, etc.), and artificial casings are cheaper and more hygienic than natural casings, and have a constant product size. Widely used because of its advantages.

However, the cellulose casing has the drawbacks of low strength and weakness to humidity, and the plastic casing cannot be smoked. Therefore, large-sized loin ham and press ham have hitherto been used. For use, a smokeable and strong fibrous casing is used.

The fibrous casing is a paper base material made of cellulose pulp impregnated with viscose, coagulated,
It has been regenerated, and this method is described in US Pat.
No. 105,273. Viscose is an aqueous solution containing 7% by weight of cellulose and 6% of sodium hydroxide, and therefore the paper base material is required to have wet strength and alkali resistance. In order to impart wet strength and alkali resistance that can withstand the above-mentioned impregnation of viscose to such a paper substrate, US Pat. Nos. 3,135,613 and 3,2
As disclosed in Japanese Patent No. 75,456, preliminary impregnation with a dilute viscose liquid (cellulose content of about 1%) and regeneration treatment are performed.

In Japanese Patent Publication No. 4-16129, a paper base material composed of cellulose pulp such as hemp pulp and wood pulp is used together with pulp or paper,
It is disclosed that chitosan or a chitosan salt is added and applied after being made into a paper base material such as a non-woven fabric, or treated by immersing it in the above aqueous solution. However, only by treating the pulp or paper base material with chitosan or chitosan salt alone, the wet strength is relatively high, but the alkali resistance is low and the strength is still insufficient.

On the other hand, a method of increasing paper strength by adding chitosan salt and polyamide epichlorohydrin resin together to a pulp slurry is disclosed in Japanese Patent Laid-Open No. 335008/53. The strength of the paper made is not yet practically sufficient.

Further, in order to impart high wet strength and alkali resistance using chitosan, it is necessary to hold the chitosan in a high ratio in the pulp fiber constituting the paper base material. The external addition method of impregnating or coating the above-mentioned chemicals on the paper base material is more efficient than the internal addition method of adding and making paper. However, in the case of the external addition method, since it is necessary to obtain a high chemical content, it is necessary to use a highly concentrated chitosan-dissolved aqueous solution, but it can be seen by measuring the chitosan-dissolved aqueous solution with a B-type viscometer. However, a high concentration chitosan-dissolved aqueous solution having a relatively high viscosity and a viscosity of more than 100 cps is very difficult to handle during impregnation or application in the actual operation, and the obtained quality varies. Is.

[0008] Therefore, when imparting high wet strength and alkali resistance to a fibrous casing base paper produced from a pulp paper base material using chitosan or a chitosan salt, the above chemicals are more preferable. It is desired to develop a formulation with good operability that can be treated at a low concentration and can be applied to a paper base material at a high content rate.

[0009]

In view of the above situation, the present inventors have proposed a method for improving the wet strength and alkali resistance of fibrous casing base paper using a paper base material composed of cellulose pulp as a raw material. As a result of intensive studies, by treating the sheet-shaped paper base material with a solution of chitosan or a mixture of a chitosan salt and a waterproofing agent,
The inventors have found that the drawbacks of the prior art can be solved, and that a paper base material having extremely excellent wet strength and alkali resistance can be obtained, and the present invention has been completed.

An object of the present invention is to provide a method for producing a base paper for a fibrous casing which is extremely excellent in wet strength and resistance to an alkaline liquid.

[0011]

The present invention provides a fibrous casing base paper comprising treating a sheet-like paper base material made of cellulose pulp with an aqueous solution of chitosan or a chitosan salt and a water-proofing agent. It is a manufacturing method.

Chitosan used in the present invention is a chitin simple substance obtained by treating a complex of chitin, calcium, protein and the like, which is usually contained in the outer shell of crustaceans such as crab and shrimp, with acid and alkali, It is obtained by treating this chitin with a strong alkali and then deacetylating it, and is generally used as a food additive. The chitosan salt is obtained by dissolving the chitosan in an inorganic acid or an organic acid.

Examples of the inorganic acid include hydrochloric acid, nitric acid, sulfuric acid,
Phosphoric acid, boric acid and the like can be mentioned, and as the organic acid, formic acid, acetic acid, glucose acid, oxalic acid, succinic acid,
Examples thereof include adipic acid, malic acid, maleic acid, fumaric acid, tartaric acid, phthalic acid, isophthalic acid, terephthalic acid and lactic acid, but when used for the fibrous casing of the present invention, acetic acid, adipic acid, malic acid. Those normally used as food additives such as fumaric acid, tartaric acid and lactic acid are preferably used.

The above-mentioned chitosan salt is soluble in water, but since chitosan is poorly soluble in water, it is used after being dissolved with the above organic acid. In this case, the amount of the organic acid used is 0. It is appropriately selected and used in the range of 1 to 1.2 times, preferably 0.3 to 0.6 times. Dissolution of chitosan with an acid is preferably carried out at a temperature of 40 ° C. or lower, preferably at room temperature of 15 to 25 ° C. for 30 to 180 minutes while stirring to suppress self-reaction.

The chitosan used has an amino group of 40
% Or more, preferably 90% or more, or those in which some or all of these amino groups are converted to ammonium groups by an acid are used. As the molecular weight of chitosan, chitosan having a molecular weight of 500,000 or less, preferably in the range of 5 to 300,000 can be used.

On the other hand, examples of the water resistant agent used together with chitosan include urea formaldehyde resin, melamine formaldehyde resin, glyoxal, dialdehyde starch, polyamide epichlorohydrin resin, polyethyleneimine, etc. Formalin-free polyamide epichlorohydrin resin is preferably used as the waterproofing agent.

In the present invention, an organic acid is added to chitosan to dissolve chitosan, and the aqueous solution is obtained by diluting with chitosan, or in the case of a chitosan salt, an aqueous solution obtained by dissolving this in water is further added with water resistance. A sheet-shaped paper base material composed of cellulose pulp is impregnated in a mixed aqueous solution consisting of adding an agent, or both surfaces of the mixed aqueous solution are sprayed, coated or coated, Then, it is dried to obtain a paper substrate treated with chitosan and a waterproofing agent.

The concentration of chitosan or chitosan salt in the above mixed water solution is 0.05 to 5.0% by weight, preferably 0.
It is appropriately selected from the range of 1 to 3.0% by weight. When the concentration is less than 0.05% by weight, the viscosity of the aqueous solution is low, but the chitosan content in the sheet-shaped paper substrate after treatment cannot be increased to a desired level, and the strength is insufficiently expressed.
The concentration of chitosan or chitosan salt in the mixed aqueous solution is 5.0.
When the content is more than wt%, the viscosity of the mixed aqueous solution becomes higher than 100 cps, the operation for treatment becomes difficult, and the content of chitosan unnecessarily increases, which is not suitable because the manufacturing cost rises. . Furthermore, it is not preferable to use a paper base material containing an excess of chitosan as a base paper for a fibrous casing as described above, because the impregnability of viscose in the post-treatment step is impaired.

On the other hand, the amount of the waterproofing agent used in the mixed aqueous solution is such that the weight ratio of chitosan: waterproofing agent is 1: 0.3.
The range is from 1: 1. If the proportion of the water-proofing agent to chitosan is less than 30%, the effect of improving the strength of the paper base material after treatment is small, and if the proportion of usage exceeds 100%, the strength reaches the saturation point. The above addition is not economically advantageous because it is wasted with a decrease in strength. The wet tensile strength according to JIS P 8135 of a paper substrate treated with a mixed aqueous solution of chitosan and a water-proofing agent, which is used for the production of fibrous casing base paper, is at least 0.70 kg / 15 mm, and alkaline according to JIS P 8135. If the wet tensile strength using a liquid is at least 0.30 kg / 15 mm, the strength quality is sufficient for practical use, so the cost of chemicals used, the viscosity of the mixed treatment liquid, and the impregnation of post-treatment chemicals such as viscose aqueous solution. A mixed solution for treating a paper base material is manufactured in consideration of properties and the like.

Examples of the method of treating the paper base material with the mixed aqueous solution include a method of impregnating the paper base material in the mixed solution, and a method of coating or coating with a size press, a roll coater, a brush coater or the like. However, the present invention is not limited by such processing method.
The conditions for drying the sheet-shaped paper base material after being treated with the mixed aqueous solution are not particularly limited, but a method using a warm air dryer at 90 to 150 ° C. is usually preferably used.

The content of chitosan in the paper base material is adjusted to 0.5 to 15% by weight of chitosan per absolutely dry paper base material by adjusting the chemical concentration in the mixed aqueous solution. If the content is less than 0.5% by weight, the strength of the paper base material after treatment is insufficient, and if the content exceeds 15% by weight,
It is necessary to make the concentration of chitosan in the mixed aqueous solution to be used higher than 5%, and since the viscosity of the mixed aqueous solution exceeds 100 cps as described above, handling of the liquid and processing becomes extremely difficult, resulting in It is not suitable because impregnation, coating or coating unevenness is likely to occur and a problem occurs in the impregnation property of viscose in the post-treatment process.

The content of the waterproofing agent in the sheet-shaped paper base material is
Since the water-proofing agent is added in proportion to the concentration of chitosan in the mixed aqueous solution, the amount of the water-proofing agent is 0.1% per paper substrate before the absolute drying treatment.
It is adjusted in the range of 5 to 15% by weight.

The sheet-like paper base material made of cellulose pulp for the present invention includes wood pulp such as bleached softwood kraft pulp and bleached hardwood kraft pulp, hemp pulp (manila hemp, sisal hemp, flax, jute), kozo. , A single pulp appropriately selected from non-wood fibers (dust fibers) such as Mitsumata or the like, or a pulp obtained by mixing these pulps, preferably hemp pulp, as a stock, obtained by papermaking in a known wet paper machine Is used. Since pulp is used to make porous paper, it is not beaten (freeness 65
0-750ml CSF) is desirable,
Depending on the application, the beading increases the bond strength, and thus pulp having a freeness reduced to 500 ml CSF may be used in whole or in part. Further, in order to impart further strength to the paper material, a chemical such as a water resistant agent or a wet strength enhancer may be added in advance for papermaking.

The basis weight of the sheet-shaped paper base material varies depending on the desired use, but for a general fibrous casing base paper, it is appropriately selected and used in the range of 15 to 30 g / m ² .

As described above, the present invention in which a sheet-like paper base material is treated with chitosan or a mixed aqueous solution of a chitosan salt and a water-proofing agent has excellent wet tensile strength and resistance to alkaline liquids. It is possible to produce a fibrous casing base paper having excellent strength without causing problems such as tearing of the base paper and paper breakage in the step of impregnating with strongly alkaline viscose.

[0026]

The present invention will be described in more detail with reference to the following examples, but of course the present invention is not limited thereto. In the examples and comparative examples,% means% by weight unless otherwise specified.

Example 1 Un-beaten (freeness 690 ml CSF) commercial Philippine hemp pulp (product number: S2-B) was adjusted to a slurry concentration of 2.5%, and a polyamide epichlorohydrin resin (WS- was used as a water-proofing agent. 570 (manufactured by Japan PMC) was added at 1.5% based on the weight of the absolutely dry pulp, and the mixture was sufficiently stirred and mixed to prepare a paper material, and a paper base material having a basis weight of 23 g / m ² was prepared in a laboratory paper machine.

On the other hand, 2 parts of acetic acid, 5 parts of chitosan (EL, manufactured by Yaizu Suisan Chemical Co., Ltd.) (the weight ratio of chitosan: acetic acid is 1:
0.4) and 93 parts of water were mixed, and chitosan was dissolved while stirring at 23 ° C. for 120 minutes. Dilute this solution with water,
Polyamide epichlorohydrin resin (W
S-570, manufactured by Japan PMC Co., Ltd.) was added. The liquid concentration after mixing was adjusted to 0.1% chitosan (EL) and 0.1% polyamide epichlorohydrin resin (WS-570).

The paper substrate was impregnated with the above-mentioned mixed solution of chitosan and waterproofing agent in a laboratory impregnator and treated to remove excess liquid using a rubber roll squeezing machine. The impregnated paper substrate was dried in a temperature-controlled hot air circulation dryer. The content of chitosan in the obtained paper substrate was 0.8% based on the paper substrate before the absolute drying treatment, and the content of the water resistant agent was 0.5%.
The wet tensile strength and alkali resistance of this paper substrate were measured by the following methods and comprehensively evaluated.

Test method (1) Wet tensile strength : According to JIS P 8135. (2) Alkali resistance : In accordance with JIS P 8135, the tensile strength was measured after the sample was immersed in a 6% sodium hydroxide aqueous solution for 10 minutes instead of water. Evaluation method Considering the wet strength of the paper base material, the value of alkali resistance, the viscosity of the impregnating liquid, and the ease of post-treatment with viscose, the good one that is practically usable is ○, the normal one that is practically usable Is indicated by Δ, and those that cannot be used in practice are indicated by x.

Example 2 A chitosan-dissolved aqueous solution similar to that used in Example 1 was diluted with water and a water-proofing agent was added, and chitosan (EL) 4.5% and polyamide epichlorohydrin resin (WS-570) 1.5% were added. The concentration was adjusted. A paper base material was impregnated with this mixed solution in the same manner as in Example 1 and dried. The content of chitosan in the obtained paper base material is 13%, and the content of the waterproofing agent is 4%.
Met. The wet tensile strength and alkali resistance of this treated paper substrate were measured and comprehensively evaluated.

Example 3 The same chitosan-dissolved aqueous solution as in Example 1 was diluted with water and a water-proofing agent was added to it, and chitosan (EL) 4.5% and polyamide epichlorohydrin resin (WS-570) 4.5% were added. The concentration was adjusted. A paper base material was impregnated with this mixed solution in the same manner as in Example 1 and dried. The content of chitosan in the obtained paper substrate was 13.0%, and the content of the waterproofing agent was 12.0%. The wet tensile strength and alkali resistance of this treated paper substrate were measured and comprehensively evaluated.

Example 4 The same chitosan-dissolved aqueous solution as in Example 1 was diluted with water and a water-proofing agent was added, and chitosan (EL) 4.5% and polyamide epichlorohydrin resin (WS-570) 6.0% were added. The concentration was adjusted. A paper base material was impregnated with this mixed solution in the same manner as in Example 1 and dried. The content of chitosan in the obtained paper substrate was 13.0%, and the content of the waterproofing agent was 15.0%. The wet tensile strength and alkali resistance of this impregnated paper base material were measured and comprehensively evaluated.

Comparative Example 1 An impregnated paper base material was produced in the same manner as in Example 1 except that only a chitosan-dissolved aqueous solution was used without using any waterproofing agent. The content of chitosan in the obtained paper substrate was 0.8% based on the paper substrate before the absolute drying treatment. The wet tensile strength and alkali resistance of this treated paper substrate were measured and comprehensively evaluated.

Comparative Example 2 An impregnated paper base material was produced in the same manner as in Example 1 except that only a chitosan-dissolved aqueous solution was used without using any waterproofing agent. The content of chitosan in the obtained paper substrate is 1
It was 3.0%. The wet tensile strength and alkali resistance of this treated paper substrate were measured and comprehensively evaluated.

Comparative Example 3 An impregnated paper base material was produced in the same manner as in Example 1 except that only a chitosan-dissolved aqueous solution was used without using any waterproofing agent. The content of chitosan in the obtained paper substrate is 1
It was 7.0%. The wet tensile strength and alkali resistance of this treated paper substrate were measured and comprehensively evaluated.

Table 1 shows the evaluation results of the paper base materials obtained in Examples 1 to 4 and Comparative Examples 1 to 3.

[0038]

[Table 1]

As can be seen from Table 1, a sheet-like paper base material composed of cellulose pulp is composed of chitosan or a chitosan salt and a water-proofing agent and has a viscosity of 100 by a B-type viscometer.
By treating with a mixed aqueous solution lower than cps, the treated paper substrate has high wet tensile strength and excellent alkali resistance (Examples 1 to 4). However, when a large amount of the water-proofing agent was contained, although the development of strength was reduced in the ratio of using the chemical (Example 4) and the chemical cost was increased, there was no problem in practical use. On the other hand, in the case of the sheet-shaped paper base material produced by impregnating only chitosan (Comparative Examples 1 to 3), if the content of chitosan is increased, the wet tensile strength is expressed to some extent, but the wet liquid using an alkaline liquid is used. The alkali resistance represented by the tensile strength does not reach a sufficiently satisfactory level (Comparative Examples 1 and 2). However, even when only chitosan is impregnated, if the content is remarkably increased, the alkali resistance increases (Comparative Example 3), but in that case, the chemical cost increases, the viscosity of the impregnation liquid increases remarkably, and the impregnation with the chitosan liquid itself occurs. There was unevenness, the quality was uneven, and the impregnation unevenness was generated in the viscose impregnation step, which was not practical.

[0040]

Industrial Applicability As described in detail above, the present invention can impart high wet strength and excellent alkali resistance to a sheet-like paper base material composed of cellulose pulp as a raw material. It is possible to provide a fibrous casing base paper for fibrous casing that does not cause troubles such as paper breakage and does not impair the effects of exhibiting the excellent strength and impregnation suitability of chitosan.

Claims (1)

[Claims] 1. A method for producing a fibrous casing base paper, which comprises treating a sheet-like paper base material made of cellulose pulp with an aqueous solution in which chitosan or a chitosan salt is mixed with a waterproofing agent.