1. A process for wet aging of beef or venison in which the beef or venison is stored in an air-tight vacuum chamber in the presence of solid alkaline and/or alkaline earth metal carbonate (3) which reacts with meat juice leaking from the beef or venison and forms a lactate with the solid alkaline and/or alkaline earth metal carbonate (3), wherein the solid alkaline and/or alkaline earth metal carbonate (3) is present in an amount of 10 to 200 g/m² and is made available in a matrix (1) of aligned and/or non-aligned fibers that absorbs the liquid leaking from the beef or venison and absorbs odors, and wherein the beef or venison and the matrix (1) are placed in the air-tight vacuum chamber, wherein the matrix (1) comprises closed side edges and a perforated film on one surface of the matrix and a nonwoven material on an opposite surface of the matrix, wherein the perforated film and the nonwoven material together wrap the matrix, wherein the perforated film is permeable to moisture, wherein the matrix comprises a cellulose layer having embossed areas distributed over its surface, wherein a fibrous web of cellulose fibers which, during production of the embossed areas, are calendered in a dotted or lined pattern and bonded together without using a bonding agent to bond together adjacent cellulose fibers in the embossed areas and provide mechanical load-bearing capacity even when wet, wherein fibers in areas outside of the embossed areas have a favorable absorption capacity compared to the cellulose fibers in the embossed areas due to loosely placed fibers in the areas outside the embossed areas, and wherein the embossed areas retain the solid alkaline and/or alkaline earth metal carbonate (3) within the embossed areas to prevent the solid alkaline and/or alkaline earth metal carbonate (3) within the embossed areas from moving inside the matrix and becoming concentrated.