FOOD PRODUCT HAVING A CASING
The present invention is directed to a process for preparing a food product having a casing, the process comprising the step of applying a casing paste comprising alginate and a sparingly soluble calcium salt by co-extrusion to the exterior of a material to be cased to form a co-extruded product, and contacting the co-extruded product with a solution comprising calcium ions, thereby causing the alginate to gel.
1 . A process for preparing a food product having a casing, the process comprising the step of applying a casing paste comprising alginate and a sparingly soluble calcium salt by co-extrusion to the exterior of a material to be cased to form a co-extruded product, and contacting the co-extruded product with a solution comprising calcium ions, thereby causing the alginate to gel.
2 . The process of claim 1 , further comprising the step of preparing an alginate paste and mixing with the alginate paste a sparingly soluble calcium salt to form the casing paste.
3 . The process of claim 1 , in which the casing paste additionally comprises a sequestrant.
4 . The process of claim 1 , in which the sparingly soluble calcium salt has a solubility product at 25° C. of not more than 10 −2 .
5 . The process of claim 4 , in which the sparingly soluble calcium salt is selected from the group consisting of calcium carbonate, calcium citrate, calcium oxide, calcium phosphate, calcium silicate, calcium sulphate, calcium sulphide, calcium tartrate and mixtures thereof.
6 . The process of claim 1 , in which the concentration of sparingly soluble calcium salt, expressed as calcium sulphate, in the casing paste is in the range 0.1 wt % to 10 wt %.
7 . The process of claim 1 , in which the time between the mixing of the sparingly soluble calcium salt and the alginate paste and the application of the casing paste is not more than 20 minutes.
8 . An alginate composition suitable for mixing with water to form an alginate paste suitable for extrusion, the composition comprising alginate, a thickener and a sequestrant.
9 . The composition of claim 8 , in which the composition is a dry powder.
10 . The composition of claim 8 , in which the composition comprises between 0.1 wt % and 25 wt % sequestrant.
11 . A food product having a casing, the casing comprising gelled alginate and further comprising a sparingly soluble calcium salt, the food product being prepared by the process of claim 1 .
12 . The food product of claim 11 , in which the sparingly soluble calcium salt has a solubility product at 25° C. of not more than 10 −2 .
13 . The food product of claim 12 , in which the sparingly soluble calcium salt is selected from the group consisting of calcium carbonate, calcium citrate, calcium oxide, calcium phosphate, calcium silicate, calcium sulphate, calcium sulphide, calcium tartrate and mixtures thereof.