Temperature ecology of molds: Across the diversity of filamentous fungi, which temperature categories are represented among different mold species encountered in foods, soils, and industrial processes?

Introduction / Context:
Temperature preferences of molds are central to food spoilage control, environmental microbiology, and biotechnology. Knowing that molds span mesophilic, psychrotrophic, and thermophilic niches explains why they appear in refrigerators, compost heaps, and ambient environments alike.

Given Data / Assumptions:

• Mesophiles grow best around 20–45 °C.
• Psychrotrophs can grow at refrigeration temperatures (often down to 0–5 °C) though their optima are higher.
• Thermophiles grow at elevated temperatures (often 45–60 °C or more).

Concept / Approach:
Different mold genera and species occupy different thermal niches driven by enzyme stability, membrane composition, and spore physiology. Industrial fermentations may leverage thermotolerant or thermophilic fungi; cold-chain spoilage highlights psychrotrophs like some Penicillium species.

Step-by-Step Solution:
Relate definitions of mesophilic, psychrotrophic, and thermophilic growth. Map common examples (e.g., Rhizopus/Penicillium at ambient; Penicillium at cold; Thermomyces at warm). Recognize that all three categories are represented among molds. Select the inclusive option.

Verification / Alternative check:
Food spoilage charts and compost microbiology both document fungal growth at low and high temperatures respectively, confirming breadth of thermal adaptation.

Why Other Options Are Wrong:
Restricting molds to one category contradicts widespread observations across environments and products.

Common Pitfalls:
Confusing “psychrophilic” (true cold-loving) with “psychrotrophic” (grow at cold but optimum higher); many food molds are psychrotrophic.

Final Answer:
All of these.