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: This invention relates to an improvement in a process for preparing humidified, shirred artificial collagen sausage casings wherein immediately prior to shirring, the inside wall of the unshirred portion of the casing is contacted with an aqueous humidifying fluid comprised of water containing from about 0.8 to about 3% by weight of a mixture of partial fatty acid esters of glycerine and sorbitol, the glycerine ester being present in the aqueous fluid at a concentration of greater than 0.1% by weight.

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 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.