PRODUCTION OF POLY ALPHA-1,3-GLUCAN FOOD CASINGS
An extrusion process for making a poly alpha-1,3-glucan food casing is disclosed.
1 . A process for making a poly alpha-1,3-glucan food casing comprising:
(a) dissolving poly alpha-1,3-glucan in a solvent composition to provide a solution of poly alpha-1,3-glucan;
(b) extruding the solution of poly alpha-1,3-glucan into a coagulation bath to make a tube-shaped wet gel;
(c) washing the tube-shaped wet gel with water;
(d) optionally, plasticizing the tube-shaped wet gel with a plasticizer additive; and
(e) removing the water from the tube-shaped wet gel to form a poly alpha-1,3-glucan food casing.
2 . The process according to claim 1 , wherein the solvent composition is an aqueous base.
3 . The process according to claim 2 , wherein the aqueous base is selected from the group consisting of aqueous potassium hydroxide, aqueous sodium hydroxide and aqueous tetraethyl ammonium hydroxide.
4 . The process according to claim 1 , wherein the solvent composition further comprises a solubility additive, a plasticizer additive or a mixture thereof.
5 . The process according to claim 1 , wherein the coagulation bath comprises an aqueous acid or methanol.
6 . The process according to claim 5 , wherein the aqueous acid comprises aqueous sulfuric acid.
7 . The process according to claim 5 , wherein the coagulation bath further comprises sodium sulfate, boric acid or a mixture thereof.
8 . The process according to claim 1 , further comprising the solution of poly alpha-1,3-glucan in (b) is coextruded over an extruded food product into a coagulation bath to make a tube-shaped wet gel covering an extruded food product.
9 . A poly alpha-1,3-glucan food casing made according to claim 1 or claim 8 .
10 . A food casing comprising poly alpha-1,3-glucan.
11 . The food casing according to claim 10 , wherein the food casing has a breaking stress from about 10 to about 100 MPa.
12 . A food casing comprising poly alpha-1,3-glucan covering a food product.