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Managing flavour and taint risk in food manufacturing

Analysis and testing Consumers and sensory

24 June 2026 | Hannah Campbell, Sensory Projects Manager, Ellie Simpson, Scientist (Chemistry and Biochemistry), and Sally Ball, Sensory Projects Manager

While safety is paramount, the quality and sensory quality of a product are equally vital to its success. Sensory quality – how a product looks, smells, tastes, and feels – can make or break the consumer experience. So, understanding and managing the flavour of your products is key.

Problems with taints and off flavours can cost food and drink companies considerable money and time through wasted product, impact on reputation and lost production. Taint is a sensory issue but often also needs chemical analysis to determine what it is and how it arose. Understanding the cause is crucial in preventing recurrences.

How flavour and taint testing works

Both instrumental and sensory techniques can be used – both individually and in combination – for the various applications of flavour and taint testing. Sensory panels (both descriptive profiling panels and discrimination panels) and analytical chemistry have their part to play.

Their applications include understanding and characterising the flavour of acceptable products, troubleshooting off flavours and taints, and proactively exploring the potential of outside sources to taint food and drink products.

Understanding/characterising the flavour profile of your product

A comprehensive picture of the sensory attributes characterising your products (and the chemistry behind this) can be of great benefit to both your business and your consumers.

Sensory descriptive profiling uses a highly trained and screened descriptive panel to characterise and quantify differences between a set of samples. This unlocks insights into products that enable clients to make more informed and meaningful commercial decisions when it comes to product development and to exploring the impacts of changes, differences between your product and a competitor’s product, and differences between varieties of raw materials.

Sensory descriptive profiling can also be used to gauge an overall profile of the sensory characteristics that define a product (useful for both R&D and quality management of ongoing production).

With instrumental methods, such as GC-MS (gas chromatography–mass spectrometry), the overall volatile profiles of samples can be assessed/compared using principal component analysis. Volatile mapping can be used for taint investigations but can also be applied to flavour analyses of acceptable samples – for example for R&D, or for examining similarities/differences between brands of the same product type or different varieties of the same raw material.

As well as understanding the sensory characteristics of your product in detail, the potential flavour impacts of changes are equally important to explore and understand. Discrimination testing is a quality assurance measure that establishes whether a panel of sensory assessors (screened for their sensory acuity and their descriptive and discrimination ability) can perceive noticeable differences between the existing and changed product. It can be applied when making changes to a product (for development, optimisation or reducing costs) to assess in what way the proposed product/process/ingredient/packaging change could affect finished product quality – namely whether regular consumers will not notice the difference.

When things go wrong – troubleshooting off flavours and taints

Off flavours are generally defined as unpleasant odours or tastes due to natural deterioration of the food. Taints, on the other hand, are usually regarded as unpleasant odours or tastes (foreign to the food / beverage product) resulting from contamination of a food by one or more extraneous chemicals. Off flavours tend to be specific for a particular product, whereas taint compounds are common across product categories.

Typical taint descriptions include, for example, 'antiseptic', 'musty', 'rancid' and 'petrol'. A manufacturer may have noticed the taint themselves or have received consumer complaints.

Taint can arise from many sources during production, transportation and storage. A few examples of taint causes include inadequately cleaned vats, treated wooden pallets, exposure to cleaning fluids, dirty bottles, or proximity to odorous substances. It can also be due to batch variation, microbial activity and deterioration of foods during storage (with rancidity being the most common deterioration). Sometimes the problem turns out to be microbiological in origin – an odour of 'nail varnish remover' or 'pear drops', for example, can arise from wild yeast contamination of baked goods.

We find that flavour/taint issues come in two main types: 1. when the client knows that there is a taint and wants to know what it is and how it might have arisen, and 2. when they think they may have a problem or where they want to assess the potential for a problem. As a very general rule of thumb, the former will rely predominantly on chemical analysis and the latter on sensory analysis. Though, for many investigations where a taint has been detected, a combination of sensory and chemical/instrumental analysis may be needed.

To investigate off flavours and taints, our expert panel of highly trained sensory assessors can conduct descriptive profiling sensory assessments on suspected tainted samples and compare this against their assessment of a control sample. Through this, they can objectively describe and quantify the intensity of the attributes perceived of the offending flavour (as well as taints in odour or aftertaste).

Based on results of the tasting / sensory assessments, we can recommend appropriate chemical/analytical tests that can measure the comparative levels of particular flavour compounds between a complaint sample / tainted product and control sample of the same product, to identify the chemical cause of the flavour/taint.

Where a particular flavour cannot be determined to be responsible for the taint, we can use other analytical instruments GC-MS to screen the samples and identify the differences between the tainted and control samples. Using GC-MS allows us to detect and identify tainting compounds without needing to know which compounds to look for beforehand.

Once we have identified the nature of an off flavour / taint through sensory assessment and confirmed it through analytical data, we can support in determining the source of the taint. For example, through our expert knowledge of raw materials and processes, we can assist in determining at which point in the supply chain / manufacturing process the cause of the problem may have occurred.

Preventing taints and proactively exploring potential sources of taint risk

You can reduce your product’s risk of becoming tainted through measures such as supplier controls / acceptance criteria, careful packaging selection (and appropriate packaging testing) and process controls (e.g. hygiene, CIP validation and residue detection, controlled storage conditions).

Another complementary strategy is to proactively review potential sources of taint risk (such as packaging materials, flooring compounds, pesticides, cleaning chemicals / disinfectants / sanitisers, and skincare) and explore this by testing their propensity to cause taint. For example, using discrimination testing to explore this.

Triangle testing (a commonly used discrimination test method) is widely used across the food industry and can be applied to almost any product type – from fresh fruits and vegetables to cooked ready meals and alcoholic beverages. These tests are a simple but powerful sensory tool, often used to verify production and formulation changes during product development or to understand how product quality may change over shelf-life.

Our use of triangle testing doesn’t stop at food and drink – we also routinely apply this method to non food products to assess their potential to cause taint (by comparing control samples and samples exposed to a potential taint sources). This is an important consideration, as non-food products used in food and beverage manufacturing, preparation or packaging environments can unintentionally impact the sensory quality of the final product.

Some examples of non food products we’ve evaluated using triangle testing include packaging materials, crop protection products (e.g. pesticides and fungicides), cosmetics and personal care products (e.g. hand washes and hand creams), cleaning chemicals (e.g. disinfectants, sanitisers, and surface cleaners) and flooring compounds (e.g. resins and multi component products).

When to use discrimination testing to explore tainting potential:

Making production lines alterations (new machinery / new cleaning regimes)
Developing/producing a new cleaning chemical / personal hygiene product / flooring compound developed, which will be marketed at hospitality / food manufacture industries
Switching to a new packaging format or developing a new packaging solution

By using sensory science in this broader context, we help clients better understand and manage the risks that non-food products may pose to final product quality.

Building a flavour quality culture

Sensory science can often be overlooked when it comes to managing quality in the factory, but it is a fundamental part of quality management – especially when it comes to managing flavour and preventing taints.

Managing quality requires proactive investigation of potential quality failures, so that control measures can be established through tolerance documentation, including analytical specifications and sensory standards (e.g. using Quality Attribute Sheets (QAS) and visual process standards).

Prior to finished product assessment, product sensory quality should be managed from the start to finish of the manufacturing process, as there are always points where product quality could fall short (or where the cause of a subsequent flavour/taint issue could occur).

Identifying potential quality failure risk points, documenting methods for controlling these, and assessing whether the controls are sufficient, provides strong evidence of due diligence. It is important to document what is working well, as well as identifying areas of improvement to elevate the sensory quality of your products.

Your partner in managing flavour and taint risk

Across our business, we have more than 200 scientists and technical experts collaborating on a wide range of projects every day.

We can characterise the sensory attributes of your product to guide product development, shelf-life validation and extension, quality control, and taint troubleshooting and prevention. Where a product has a taint, we offer a range of sensory and instrumental techniques and can help you apply the right ones to identify the cause and prevent reoccurrence.

We also provide consultancy, guidance and training in product quality planning and sensory assessment – to help you maximise your product’s sensory quality.

So, whether you are dealing with a taint challenge, want a more complete understanding of your existing product’s flavour, or are developing something new, get in touch for the support.