Food casing with permeability to smoke and water vapour and with improved transparency

A tubular, seamless, biaxially stretched, smoke-permeable and water vapour-permeable, coloristically neutral and transparent, single-layer food casing composed of a mixture comprising at least one aliphatic (co) polyamide and at least one vinyl (co) polymer having units of N-vinyl-2-pyrrolidone,

• wherein the at least one aliphatic (co) polyamide is present at a fraction of 50 to 95% by weight and the at least one vinyl (co) polymer is present at a fraction of 3 to 40% by weight, based in each case on the weight of the mixture,
• and the mixture further comprises 1.5 to 7.0% by weight, based on the mixture weight, of at least one aliphatic diol and/or aliphatic polyol, where the diol or polyol is homogeneously distributed in a matrix of the aliphatic (co) polyamide,
• the food casing has a total luminous transmittance of at least 80%, determined on a casing having a thickness of 25 to 30 μm in the wavelength range from 380 to 780 nm with a spectrophotometer,
• the food casing has a total haze of less than 10%, determined according to ASTM D 1003-6113, procedure A, without oil immersion, and
• the food casing does not comprise discrete domains.