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By Pareire Consulting Ltd

Mead, one of the world’s oldest fermented beverages, is experiencing renewed

commercial interest. However, modern production particularly at scale and for

regulated markets requires a level of scientific validation and stability assurance that

goes well beyond traditional craft practices. Ensuring product stability is not only a

matter of quality; it is central to food safety, regulatory compliance, and brand integrity.

At Pareire Consulting, we are working alongside producers including Wild Atlantic

Mead and engaging with research bodies such as Teagasc, to develop structured

stability testing protocols appropriate for mead products at approximately 10% ABV.

This work reflects both regulatory expectations and emerging best practice within the

fermented beverage sector.

The Nature of Stability in Mead

Unlike distilled spirits, mead at ~10% alcohol by volume (ABV) does not inherently

guarantee microbiological or chemical stability. It sits closer to wine in its risk profile,

where multiple interacting variables—including pH, residual sugar, oxygen exposure,

and microbial load—can influence shelf life.

As outlined in current production frameworks, stability must be assessed across

three core domains:

a. Microbiological stability (absence of spoilage organisms or refermentation)

b. Chemical stability (maintenance of parameters such as pH, volatile acidity,

and sulphur dioxide levels)

c. Physical and sensory stability (clarity, colour, aroma, and taste over time)

Failure in any of these areas may lead to product spoilage, quality degradation, or in

certain cases, packaging failure.

Microbiological Risks and Refermentation

One of the primary risks in mead production is unintended refermentation in bottle.

This can occur where residual sugars remain and viable yeast or bacteria are

present. Mead, particularly when produced with minimal intervention, may contain:

a. Wild or cultured yeast strains

b. Lactic acid bacteria

c. Acetic acid bacteria

If not adequately controlled, these organisms can metabolise residual sugars post-

bottling, leading to:

Disclaimer-The information provided reflects current knowledge and sources considered reliable at the time of

writing. While care has been taken in its preparation, Pareire Consulting Ltd does not guarantee completeness or

ongoing accuracy.1. Carbon dioxide (CO₂) generation and pressure build-up

2. Turbidity or sediment formation

3. Off-flavours, including sour or vinegar notes

Fleet, 2003; Waterhouse et al., 2016 highlights that even low levels of microbial

contamination in wine-like beverages can result in measurable spoilage over time.

Accordingly, stability protocols typically require non-detectable microbial counts at

bottling and verification over time intervals (e.g. 3, 6, and 12 months).

Chemical Stability and Oxidation

Chemical stability is equally critical. Mead is particularly susceptible to oxidation due

to its composition and often delicate aromatic profile derived from honey.

Key parameters include:

a. pH (target typically approximately 3.2–4.0)

b. Volatile acidity (indicator of spoilage)

c. Dissolved oxygen levels

d. Sulphur dioxide (SO₂), where used

Exposure to oxygen—either during processing, bottling, or through closure systems

can lead to:

1. Browning of the liquid (Maillard-type reactions and polyphenol oxidation)

2. Loss of floral and honey-derived aromatics

3. Development of stale or sherry-like notes

Research from the International Organisation of Vine and Wine and studies such as

Ribéreau-Gayon et al. (2006) demonstrate that oxidation is one of the principal drivers

of quality degradation in wine-equivalent beverages.

Light Degradation

Although less frequently discussed in mead compared to beer, light exposure can also

contribute to product degradation. Ultraviolet (UV) and visible light can accelerate

oxidative reactions and degrade aromatic compounds.

Potential impacts include:

a. Loss of volatile floral compounds from honey

b. Development of atypical or “flat” sensory profiles

c. Colour changes over time

Disclaimer-The information provided reflects current knowledge and sources considered reliable at the time of

writing. While care has been taken in its preparation, Pareire Consulting Ltd does not guarantee completeness or

ongoing accuracy.For this reason, stability testing frameworks often include light exposure conditions

simulating retail environments, and packaging selection (e.g. amber vs clear glass)

becomes a relevant control measure.

Temperature Sensitivity and Storage Conditions

Temperature is a critical factor influencing both chemical and microbiological stability.

Elevated temperatures can accelerate reaction rates and exacerbate spoilage risks.

Testing protocols typically include:

a. Ambient conditions (approximately 20°C) to simulate normal storage

b. Elevated conditions (30–40°C) for accelerated stability assessment

Exposure to higher temperatures, even over short durations (e.g. transport or

warehousing), may result in:

1. Increased oxidation rates

2. Volatile aroma loss

3. Expansion of dissolved gases and potential pressure issues

4. Enhanced microbial activity where present

From a sensory perspective, temperature abuse can lead to noticeable taste and

odour deviations, including cooked, muted, or slightly sour notes.

Sensory Risks: Odour Contamination and Pre-Bottling Factors

A less obvious but important consideration is exposure to strong odours during

production and pre-bottling handling. Mead, due to its relatively delicate aromatic

profile, may absorb volatile compounds from the surrounding environment.

Risks include:

a. Cross-contamination from cleaning agents or nearby products

b. Absorption of environmental odours during storage or transfer

c. Packaging-related taints (e.g. from closures or adhesives)

These factors can result in:

1. Off-aromas detectable at low thresholds

2. Perceived “taint” that affects consumer acceptance

3. Variability between batches

Industry guidance from organisations such as the Food Safety Authority of Ireland

emphasises the importance of controlled production environments and validated food-

contact materials to mitigate such risks.

Disclaimer-The information provided reflects current knowledge and sources considered reliable at the time of

writing. While care has been taken in its preparation, Pareire Consulting Ltd does not guarantee completeness or

ongoing accuracy.Packaging and Closure Integrity

Packaging plays a central role in maintaining stability. As identified in the current

production framework, risks associated with packaging include:

a. Oxygen ingress through closures (e.g. cork variability)

b. Migration of substances from packaging materials

c. Seal failure leading to leakage or contamination

Testing requirements typically include:

1. Closure integrity testing

2. Migration compliance (EU 1935/2004)

3. Dissolved oxygen monitoring post-bottling

Closure selection is particularly important for mead, where oxygen sensitivity may be

higher than in some wines.

Shelf Life and Post-Opening Stability

Beyond unopened shelf life, consideration must also be given to product behaviour

after opening. Once exposed to air, mead may undergo:

a. Rapid oxidation

b. Aroma loss

c. Microbial exposure

Internal testing considerations include evaluating whether the product maintains

acceptable quality:

1. After 3 days refrigerated storage

2. Following short-term temperature exposure scenarios

Such testing supports the development of evidence-based consumer guidance and

reduces the risk of misleading shelf-life claims.

Structured Stability Testing with Teagasc

The collaboration with Teagasc is focused on establishing a structured, evidence-

based stability programme aligned with both regulatory expectations and scientific

best practice.

Key elements include:

a. Defined analytical parameters (ABV, pH, acidity, SO₂, residual sugar)

b. Microbiological testing to confirm absence of spoilage organisms

Disclaimer-The information provided reflects current knowledge and sources considered reliable at the time of

writing. While care has been taken in its preparation, Pareire Consulting Ltd does not guarantee completeness or

ongoing accuracy.c. Physical assessments (clarity, colour, CO₂ stability)

d. Sensory evaluation by trained panels

e. Multi-condition storage studies (ambient, elevated temperature, light

exposure)

The intended outcome of this work is to support:

1. A documented stability report

2. A justified shelf life

3. Clearly defined storage instructions

Regulatory and Compliance Context

From a regulatory perspective, stability is closely linked to multiple compliance

requirements, including:

a. Accurate ABV (alcohol) declaration

b. Food safety obligations under Food Business Operator (FBO) registration

c. Traceability and batch control

d. Packaging and labelling compliance

As outlined in the current compliance framework, absence of stability data represents

a critical risk, potentially leading to product recall or regulatory action.

Important Considerations and Limitations

It is important to note that stability outcomes are product-specific and depend on

formulation, processing methods, and packaging choices. The approaches described

above reflect current best practice but do not eliminate all risks.

Accordingly:

a. Stability testing must be conducted on the final commercial product

b. Results should be independently verified where required

c. Shelf-life claims must be supported by documented evidence

Conclusion

The production of stable, high-quality mead at approximately 10% ABV requires a

multidisciplinary approach combining microbiology, chemistry, packaging science, and

regulatory compliance. While traditional methods provide a foundation, modern

commercial production necessitates structured validation and ongoing monitoring.

Through collaboration with producers and research institutions such as Teagasc,

Pareire Consulting Ltd is supporting the development of robust, evidence-based

Disclaimer-The information provided reflects current knowledge and sources considered reliable at the time of

writing. While care has been taken in its preparation, Pareire Consulting Ltd does not guarantee completeness or

ongoing accuracy.stability frameworks designed to meet both regulatory expectations and consumer

quality standards.

References (indicative)

1. 2. 3. 4. 5. Fleet, G.H. (2003). Yeast interactions and wine flavour. International Journal

of Food Microbiology

Ribéreau-Gayon, P. et al. (2006). Handbook of Enology

Waterhouse, A.L. et al. (2016). Understanding Wine Chemistry

International Organisation of Vine and Wine guidelines

Food Safety Authority of Ireland guidance documents