Food and beverage enzymes — source of protease used for sake flavour development and haze removal Which microorganism is the standard industrial source of the protease employed to enhance flavour and reduce haze in sake processing?

Introduction / Context:
Sake brewing relies on koji molds to generate a suite of enzymes that saccharify starch and modulate protein-derived haze and flavour. Understanding the enzyme source helps technologists select safe, GRAS organisms and optimize process conditions.

Given Data / Assumptions:

• Protease activity reduces protein haze and releases flavor-active peptides and amino acids.
• Koji production in sake traditionally uses Aspergillus oryzae.
• Food safety and toxin concerns preclude use of some Aspergillus species (for example, aflatoxin producers).

Concept / Approach:
Aspergillus oryzae is a domesticated koji mold, long recognized for producing amylases, proteases, and other hydrolases under controlled solid-state cultivation. It is GRAS and central to East Asian fermentations. A. flavus is aflatoxigenic and unsuitable; Bacillus cereus is a foodborne pathogen; A. niger is widely used for other enzyme preparations but is not the canonical source for sake koji proteases.

Step-by-Step Solution:
Identify the GRAS koji mold used in sake: A. oryzae.Relate protease function to haze reduction and flavour development.Exclude unsafe or non-standard organisms.

Verification / Alternative check:
Brewing texts and enzyme supplier catalogs list A. oryzae-derived proteases for beverage clarification and flavor optimization.

Why Other Options Are Wrong:
A. flavus poses aflatoxin risk; B. cereus is unsuitable; A. niger is valuable industrially but not the classic koji protease source for sake.

Common Pitfalls:
Assuming all Aspergillus species are interchangeable; safety and tradition strongly favor A. oryzae in sake.

Final Answer:
Aspergillus oryzae.