Oxidised Flavour Standard For Sensory Training

WHAT IS OXIDISED FLAVOUR?

Oxidised flavour refers to a group of undesirable aromas and tastes that develop when oxygen reacts with compounds in beer or beverages. These flavours are commonly described as:

– Flat or stale
– Old or aged
– Grape-like
– Sherry-like

Oxidation reduces freshness and vibrancy, masking desirable hop, malt, or fermentation characteristics. It is one of the most common and commercially damaging off-flavours encountered in packaged beverages.
 

WHAT CAUSES OXIDISED FLAVOUR?

Oxidation typically occurs when:

– Oxygen is introduced during packaging (bottling, canning, or kegging)
– Dissolved oxygen levels are not adequately controlled
– Seals, closures, or packaging materials allow oxygen ingress
– Products are stored improperly or for extended periods

Chemically, oxygen triggers reactions that create free radicals. These reactions can both degrade fresh flavour compounds and accentuate specific sulphur-derived notes, resulting in characteristic oxidised off-flavours—often noticeable within weeks of packaging, particularly in lagers and delicate beer styles.
 

USING THE OXIDISED FLAVOUR STANDARD FOR SENSORY TRAINING

The oxidised flavour standard is specifically designed for structured sensory training and calibration. It allows tasters to:

– Experience oxidation in a controlled, repeatable format
– Train recognition of early-stage oxidation
– Improve consistency across tasting panels
– Benchmark real samples against a known reference

By simulating realistic oxidation profiles, the standard helps sensory professionals build confidence and accuracy when evaluating freshness, stability, and shelf-life performance.
 

HOW TO RECOGNISE OXIDISED FLAVOUR: SENSORY TERMS

Common sensory descriptors associated with oxidised flavour include:
– Oxidised beer
– Flat
– Old
– Aged
– Grape-like
– Sherry-like

These descriptors are essential vocabulary for professional tasters and are reinforced through repeated use of the flavour standard during training sessions.
 

WHAT ARE THE PROFESSIONAL APPLICATIONS OF THE OXIDISED FLAVOUR STANDARD?

The Oxidised Flavour Standard serves multiple professional applications:

– Brewmasters and beer tasters use it to identify and quantify oxidation-related off-flavours, helping them assess packaging performance, oxygen control, and freshness across different beer styles, particularly lagers and delicate hop-forward beers.
– Quality control and quality assurance teams rely on it to establish sensory acceptance thresholds, monitor batch-to-batch consistency, and detect early signs of oxidation before products are released to market.
– Packaging and production specialists apply it to evaluate the impact of filling lines, closures, and packaging materials, supporting improvements in oxygen management and shelf-life stability.
– Shelf-life and stability testing professionals use the standard to benchmark how oxidation develops over time, enabling informed decisions on storage conditions, distribution timelines, and best-before dating.
– Sensory analysts and training coordinators employ it as a calibrated reference in sensory training programmes, ensuring consistent flavour recognition, panel alignment, and reliable sensory performance across teams, sites, and certification schemes within the beverage industry.
 

OTHER INFORMATION

Please note: This FlavorActiV GMP Flavour Standard is proprietary –a superior product from a quality testing perspective, designed to represent an off-flavour type that can occur in beer at a specific oxidation profile. Other flavours within our range can fit older oxidation profiles, such as Papery and Catty.