Abstract: In a process for producing a tubular collagen casing from a hide collagen source which comprises the steps of comminuting said collagen and forming a slurry, swelling said collagen with acid, then extruding, coagulating, tanning, and drying, the improvement which comprises the steps of substantially completely swelling collagen, in which the epidermal layer and hair has been removed, with a relatively concentrated weak non-toxic acid having a dissociation constant in water of from about 1.times.10.sup.-6 to about 1.times.10.sup.-3, e.g., lactic acid, citric acid, etc., for a time sufficient to effect substantial swelling of the collagen and then comminuting the collagen for forming a slurry. An advantageous feature of this improvement is that it permits forming desirable collagen casing from a collagen source obtained from a hide which has been subjected to substantial liming.

Abstract: A method for coloring synthetic food casings such as casings manufactured from cellulose and collagen wherein the tubular casing in the gel state is impregnated with a solution containing caramel and thereafter the caramel is cross-linked and insolubilized in the casing to effect permanent coloring of the casing.

Abstract: The filterability of aluminum salts precipitated from an aqueous solution containing dissolved aluminum ion is improved by adjusting the pH of the solution to between about 4 and 6, adding less than a stoichiometric amount of a 1, 3-dicarbonyl compound such as acetylacetone to the solution to precipitate the aluminum dicarbonyl and then adding a sufficient amount of an alkaline hydroxide to precipitate the remaining dissolved aluminum ion in the form of aluminum hydroxide to obtain a mixed precipitate which can be readily filtered.

Abstract: Xanthate esters of the form: ##EQU1## where R is an alkyl function having at least one H in a position alpha to the R - O bond, (C).sub.n is a linear alkyl function either substituted or unsubstituted, with n = 1 - 3, X has a basicity greater than the >C = S function and comprises a C or S containing functional group having at least one double or triple bond to a hetero atom, the functional group being connected to (C).sub.n through C or S; are reacted with Lewis acids, either neat or in non-protonic non-aqueous solvents, to yield novel Lewis acid complexes of the esters. The Lewis acid -- xanthate ester complex is decomposed by admixture with water or a protonic non-aqueous solvent, e.g. methanol, ethanol, etc., glycol, cellosolve, liquid ammonia, lower alkyl primary or secondary amines, aniline, etc., to yield an unsaturated derivative of R.

Abstract: Aqueous dispersions of swollen hide collagen suitable for extrusion into tubular food casings are prepared by dispersing finely comminuted collagen particles at a concentration of 2-8% by weight in water. Swelling of the collagen particles is effected by adjusting the pH of the dispersion to between 2.5 to 3.7 with a mixture of a strong acid having a dissociation constant in water at 25.degree. C of greater than 1 .times. 10.sup.-.sup.3, e.g., sulfuric acid, and a weak acid having a dissociation constant in water at 25.degree. C between 1 .times. 10.sup.-.sup.6 to 1 .times. 10.sup.-.sup.3, e.g., lactic acid.

Abstract: This invention relates to a process for improving the vapor barrier properties of a shaped article having relatively poor vapor barrier characteristics, said article shaped from a polymer having a plurality of carboxylic acid salt groups formed by the reaction of pendant carboxylic acid groups and a cation which compises:Displacing at least a portion of the cations in said polymer by contacting the surface of said shaped article with an effective proportion of an acid having a sufficient degree of ionization and for a time to displace said cation, thereby generating pendant carboxylic acid groups;Coating the contacted surface of said shaped article with an organic polyisocyanate;Bonding said organic polyisocyanate to said shaped article by reacting the isocyanate groups with said pendant carboxylic acid groups; andApplying a coating having vapor barrier characteristics to said shaped article.

Abstract: This invention relates to an improvement in a process for threading an edible collagen casing through an elongated dryer wherein the casing is inflated with a gas, sealed at an end for maintaining said gas in said casing, and then passed through the dryer. The improvement in the process resides in injecting a gas-forming material selected from the group consisting of a water-immiscible liquid having a boiling point of from about 10.degree. - 70.degree.C. at atmospheric pressure, a solid sublimable at a temperature below about 70.degree.C. at atmospheric pressure, and a solid or liquid which is decomposible at a temperature below about 70.degree.C. at atmospheric pressure into the bore of the casing prior to introducing the casing into the dryer. The elevated temperature maintained in the dryer causes the gas-forming material to vaporize, sublime, react, or decompose to a gas and thereby inflate the casing. The material is added in a proportion sufficient to inflate the casing to a predetermined pressure.

Abstract: An improved process for tanning edible collagen food casings wherein the coagulated and washed collagen casing is exposed to a tanning bath which is free of aluminum chelating reagents and contains a mixture of aluminum ammonium sulfate, as A1NH.sub.4 (SO.sub.4).sub.2. 12H.sub.2 O and monobasic aluminum sulfate (A10HSO.sub.4), the concentration of the aluminum ammonium sulfate in the bath being less than 3% by weight and the molar ratio of aluminum ammonium sulfate to monobasic aluminum sulfate being in the range of 1:2 to 2:1.

Abstract: The storage life of fresh meat normally subject to deterioration is extended by wrapping the meat in a first film which is permeable to a sterilizing agent but impermeable to bacteria, injecting a sterilizing agent through said first film for killing at least a substantial proportion of the bacteria on the surface of the meat, and then enclosing the sterilized meat in a second film which is substantially impermeable to oxygen for retarding aerobic bacterial growth.

Abstract: This invention relates to an improvement in a process for preparing reinforced, artificial sausage casings wherein a tubular porous web is passed through a die, impregnated with a polymeric dope, and the polymer regenerated. The improvement resides in employing a porous web having incorporated therein from about 25 to 500 ppm based on the dry weight of the porous web of an alkyl imidazoline ethoxylate of the formula ##EQU1## wherein R is a fatty acid radical having from 10 - 22 carbon atoms in the structure and x is a number from about 3 - 10.

Abstract: This invention relates to a tubular mold having excellent resistance to stretch. The mold is a "duplex type" flexible tubular mold comprising an outer film laminate comprising:A first film ply of cellophane having a saran film bonded to its outer and inner surfaces;A second film ply of biaxially oriented polypropylene having saran coatings bonded to its outer and inner surfaces, the film ply being bonded to the coated cellophane by an adhesive; andAn inner film laminate comprising a film ply of biaxially oriented polypropylene having a saran coating on both sides.

Abstract: This invention relates to a method for preparing a collagen casing from a collagen source which had been subjected to a rigourous liming for effectively completely liming the hide collagen. The fully limed hide collagen is soaked in a dilute edible acid having a pH below about 5.5 for a time sufficient to reduce the pH in the center of the hide to about 4 - 5.5, and then washing the neutralized hide with water until the pH of the supernatant after a 20 minute exposure with the hide, is within about 0.2 pH units of that of the incoming water. The hide is then ground and formed into a collagen slurry and processed in conventional manner into edible collagen casings.