Posted on by Cheese Wiki

Wiki: Surface Defects, Mold

Surface mold defects of cheese are normally cheese type dependent. Molds are common micro-organisms and some are intentionally used in cheese making for their effect on texture and flavour such as white for Camembert and blue for Blue cheeses. This wiki article is not for those but for molds on the surface of cheeses which result in unwanted textures or flavours, their common colour, causes and solutions. 

Blue-Green

Two 4 pound Gouda's with Canola oiled rinds, one with blue surface mold, second after brush and water cleaning.
Two 4 pound Gouda's with Canola oiled rinds, one with blue surface mold, second after brush and water cleaning.

Description

  • Blue to green colour on surface of cheese.

Causes

  • Contamination by airborne Penicillium rocqueforti mould commonly intentionally used in making blue type cheeses due to high humidity. Not dangerous, but visually unappealing when unwanted.

Solutions

  • Wipe or brush off of cheese and rub rind with mixture of vinegar and dry salt. Lower aging humidity and ensure that area is clean and cannot harbor mould.

Black

Description

  • Black colour on surface of cheese.

Causes

  • Contamination by airborne Mucor or pin mould due to high humidity. Not dangerous, but visually unappealing.

Solutions

  • Wipe or brush off of cheese and rub rind with mixture of vinegar and dry salt. Lower aging humidity and ensure that area is clean and cannot harbor mould.

Brown

4 pound Havarti with good white Geotrichum candidum mold and unwanted brown mold on rind.
4 pound Havarti with good white Geotrichum candidum mold and unwanted brown mold on rind.

Description

  • Brown colour on surface of cheese.

Causes

  • Contamination by airborne mould due to high humidity. Not dangerous, but visually unappealing.

Solutions

  • Wipe or brush off of cheese and rub rind with mixture of vinegar and dry salt. Lower aging humidity and ensure that area is clean and cannot harbor mould.

Pink

Description

  • Pink colour on surface of cheese.

Causes

  • More common in Penicillium candidum (white mould) cheese when aging area’s humidity is too high, reduce humidity.

White

2 kg Havarti with good white Geotrichum candidum surface mold.
2 kg Havarti with good white Geotrichum candidum surface mold.

Description

  1. White coloured powdery mold on surface of cheese. Smells earthy like sweet smelling root cellar with faint hints of fermentation.
  2. White fuzzy mold like on Camembert & Brie.

Causes

  1. Normally from Geotrichum candidum and actually a good protective mold but included in this article for completness.
  2. Normally from Penicllium candidum and normally only wanted on white bloomy type rinds such as Camemberts and Bries.

Solutions

  1. None, do not remove as good mold.
  2. Wipe or brush off of cheese and rub rind with mixture of vinegar and dry salt. Lower aging humidity and ensure that area is clean and cannot harbor mould.