Difference Between Mold and Mildew

Main Difference – Mold vs Mildew

Mold and mildew are two common types of fungi found in moist environments. Both types of organisms spread easily and are difficult to get rid of. Therefore, both mold and mildew cause health problems and structural damages on the surfaces they grow. Mildew is a type of mold. Both mold and mildew are composed of filaments with multiple, identical nuclei. The main difference between mold and mildew is that mold penetrates the surface of the attached material whereas mildew grows on the surface of the material. Mold mainly grows on food as well as permanent materials while mildew grows on damp surfaces of papers, fabrics, and various organic materials.

Key Areas Covered

1. What is Mold
      – Definition, Structure, Characteristics
2. What is Mildew
      – Definition, Structure, Characteristics
3. What are the Similarities Between Mold and Mildew
      – Outline of Common Features
4. What is the Difference Between Mold and Mildew
      – Comparison of Key Differences

Key Terms: Downy Mildew, Filamentous Fungi, Mildew, Mold, Organic Materials, Penicillium, Powdery Mildew

Difference Between Mold and Mildew - Comparison Summary

What is Mold

Mold is  a growth of fungus, which occurs on food or on other organic materials under moist and warm conditions. More than 10,000 mold species can be identified living indoors. The growth of mold may occur in the form of spots, which smells musty. The color of the patch can be either white, blue, green, black, brown or gray. The appearance of the patch can be either fuzzy or slimy. Since the fungal hyphae of mold can penetrate the organic material on which they grow, the growth of mold on an organic surface may destroy the material eventually. Typically, household molds can be divided into five groups; Alternaria, Aspergillus, Cladosporium, Penicillium, and Stachybotrys chartarum (black mold). A slime mold is shown in figure 1.

Difference Between Mold and Mildew

Figure 1: A Slime Mold

Molds are used in the food industry to make cheese. Penicillium is used to produce antibiotics such as penicillin. The exposure to mold may cause coughing, stuffy noses, eye, skin or throat irritation.

What is Mildew

Mildew is a thin coating of filamentous fungi, growing on plants or damp organic matter. It typically has a cottony, whitish color, and coats the surface of the affected organic matter. Mildews grow on damp, warm, organic surfaces such as paper, fabrics, and other household organic matter. Since mildew grows only on the surface, it can be cleaned more easily than molds. The two common types of mildew are powdery mildew and downy mildew. Powderly mildew mainly affects flowering plants. They first appear as white or gray patches and eventually become yellowish brown or black. Downy mildew generally occurs in agricultural products such as potatoes and grapes. Downy mildew mainly occurs as yellow patches, which eventually become brown. The powdery mildew and downy mildew are shown in figure 2.

Main Difference -Mold vs Mildew

Figure 2: Powdery Mildew and Downy Mildew

Ideally, mildew has no any beneficial uses as molds. The spores of mildew may cause coughing, sore throat, respiratory problems, and headache.

Similarities Between Mold and Mildew

  • Both Mold and Mildew are two types of filamentous fungi.
  • Both mold and mildew grow on damp, organic material.
  • Both mold and mildew easily spread and are difficult to remove.
  • Both mold and mildew cause health problems as well as structural damages to the material they grow.
  • Keeping moisture-free areas may prevent the growth of both mold and mildew.

Difference Between Mold and Mildew

Definition

Mold: Mold is a fungus that occurs on food or on other organic materials under moist and warm conditions. 

Mildew: Mildew is a thin coating of filamentous fungi, growing on plants or damp organic matter.

Habitat

Mold: Molds grow on food or on permanent materials such as walls.

Mildew: Mildews grow on papers, fabrics, and other household, organic materials.

Penetration

Mold: Mold penetrates the surface of the attached material

Mildew: Mildews only grow on the surface of organic materials.

Growth

Mold: Mold may be fuzzy or slimy.

Mildew: Mildew grows in a flat pattern. It can be either a powdery or fluffy growth.

Color of the Patch

Mold: The patch of the mold can be white, blue, green, black, brown or gray in color.

Mildew: The patch of the mildew can be white, gray or yellowish in color.

Over Time

Mold: The organic matter that is covered by the mold become rotten over time.

Mildew: The patch of the mildew becomes brown or black color over time.

Common Types

Mold: Alternaria, Aspergillus, Cladosporium, Penicillium, and Stachybotrys chartarum (black mold) are the common types of molds.

Mildew: Powdery mildew and downy mildew are the common types of mildews.

Health Problems

Mold: Prolonged exposure to mold can cause allergic reactions, respiratory problems, inflammation, migraines, extreme fatigue, and pain in joints.  

Mildew: The spores of mildew may cause coughing, sore throat, respiratory problems, and headache. 

Effect of Bleaching

Mold: The color of the mold remains as it is after bleaching.

Mildew: The color of the mildew becomes lighter after bleaching.

Uses

Mold: Molds are used in the production of cheese and the production of some medicines such as penicillin.

Mildew: Mildew shows no beneficial uses.

Conclusion

Mold and mildew are two types of harmful fungal types, which grow on the surfaces of household organic matter. Both mold and mildew are made up of filamentous hyphae. Mold penetrates the organic matter while mildew only grows on the surface of it. Thus, the main difference between mold and mildew is their type of growth.

Reference:

1.“MOLD.” Chicora Foundation, Available here.
2.“Mildew.” Mold Bacteria Facts, 22 June 2014, Available here.

Image Courtesy:

1. “Slime mold (NHGRI)” By Dr. Jonatha Gott and the Center for RNA Molecular Biology, Case Western Reserve University. – Courtesy “National Human Genome Research Institute” (Public Domain) via Commons Wikimedia
2. “Downy and Powdery mildew on grape leaf” – original uploader was Agne27 at English Wikipedia(Original text: David B. Langston, University of Georgia, United States) – USDA ARS (Public Domain) via Commons Wikimedia

About the Author: Lakna

Lakna, a graduate in Molecular Biology & Biochemistry, is a Molecular Biologist and has a broad and keen interest in the discovery of nature related things

Leave a Comment