Developing vegan mayonnaise

It’s no secret that veganism is on the rise, with many people choosing to either minimise their intake of animal products or cut them out entirely. After conducting consumer research into this growing market, a leading food manufacturer identified vegan mayonnaise as a new product development opportunity and partnered with RSSL’s experienced team to take the project forward.

The challenge

 

Mayonnaise has historically relied on eggs to create the characteristics consumers have come to expect. It’s the magic ingredient, with the lecithin in the egg yolk stabilising the emulsion of oil and water that forms the base of the mayonnaise and creates the sought-after thick and creamy texture. Developing a vegan alternative can therefore be tricky.

 

Although modified starches are typically used to remove the egg in mayonnaise, it’s important to understand how their different structures and properties may influence the final product’s texture and viscosity - and ultimately the consumer experience.

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Mastersizer RD 4515 HR

Our expert team began the project by creating a series of concepts that used a range of different emulsifying and stabilising ingredients, which were then prototyped and evaluated against a benchmark commercial mayonnaise. This allowed us to ascertain which ingredients from which suppliers performed best and then optimise the final formulation for launch.

 

It was also vital that we objectively measured the viscosity of the prototypes. This analytical parameter not only directly correlates to mouthfeel and spreadability - both of which are essential for consumer acceptance - it can also significantly impact on a number of other product properties including processability and delivery from the container. Analysing this aspect during the development process, enabled us to understand the impact of formulation changes without the need for a full sensory evaluation, identify unsuccessful prototypes early on and predict favoured formulations.

 

So what did this look like in practice?

A key part of the brief was to create a high-quality vegan product, which would meet discerning consumer expectations by successfully replicating the eating experience of conventional mayonnaise.

 

 

Stage one: key ingredient selection

 

We initially evaluated two prototypes to determine the supplier of one of the key ingredients. Using a simple rotational rheology measurement, we determined that Prototype 2 had significantly lower viscosity than Prototype 1 and the commercial benchmark. As shown in Figure 1, the application of shear stress required to maintain flow across the entire range of shear rates tested was lower for this prototype.

 

In addition, our analysis showed that Prototype 1 had a comparable ‘yield stress’ to the commercial benchmark, which was orders of magnitude above Prototype 2. This non-zero shear stress at zero shear rate confirmed that both Prototype 1 and the commercial benchmark were ‘structured liquids’; they behaved as solids until a force exceeded the yield stress and compelled them to flow. This meant that both would form a classic well-defined ‘dollop’ of mayonnaise and spread easily without running off the knife.

 

 

 

 

 

 

Figure 1: Shear stress as a function of shear rate for initial prototype

and benchmark samples.

 

 

 

 

 

Stage two - recipe optimisation

 

We then needed to ensure that the final vegan mayonnaise formula would remain a stable emulsion for the entirely of its shelf life. To do so, we generated a further four prototypes based on Prototype 1, with varying levels of other stabilising and emulsifying ingredients.

 

Each was then subject to an accelerated stability study using LUMiSizer technology; an analytical centrifuge that monitors changes in light transmission through a sample in order to identify separation events, such as creaming and sedimentation.

 

Analysis of the results showed early on that Prototypes 1A and B were unstable emulsions, with creaming occurring that left behind a clear aqueous layer at the bottom of each sample (see Figure 2).

 

Within the three-hour study, Prototype 1D also showed a destabilisation process at a later stage (after 400 profiles), indicating that this prototype would also have a shorter shelf life than the commercial benchmark. In contrast, Prototype 1C matched the stability profile of the benchmark.

 

 

 

Figure 2. LUMiSizer tracking of creaming process, images adapted

from https://lum-gmbh.com.

 

 

 

Figure 3. Progression of transmission fingerprint during analysis

for prototype vegan mayonnaises.

 

Within the three-hour study, Prototype 1D also showed a destabilisation process at a later stage (after 400 profiles); indicating that this prototype would also have a shorter shelf life than the commercial benchmark. In contrast, Prototype 1C matched the stability profile of the benchmark.

 

All of this was confirmed by the Instability Index of each prototype, as calculated by the LUMiSizer (see Table 1), providing a simple ranking of each sample.

Table 1: Instability index

Stage 3 - Claim substantiation and manufacturing

 

Once the final formula had been established, the next step focused on determining the information that could be included on the product label.

 

As this vegan product was to be manufactured in a non-dedicated site, any risks of the unintentional presence of animal-derived material needed to be assessed. This was vital given that consumers may use vegan products as a way to avoid animal-derived food allergens, as well as make lifestyle-driven dietary choices.

 

RSSL carried out a comprehensive assessment of potential risks both within the supply chain and the manufacturing process. The outcome of which would either be used to substantiate a vegan claim or indicate that the unintentional presence of animal-derived allergens needed to be communicated to the consumer.

 

 

Supply chain

 

Our risk assessment began with the supply chain. If the manufacturer was buying in materials that unintentionally contained animal-derived materials, there would be no way to then manage them back out - so this was a fundamental aspect of our overall review.

 

On-site visits to suppliers were conducted to allow for a full understanding of how the manufacturer managed materials and to assess the evidence that planned controls to minimise the risk of contamination from animal-derived materials were effective. The manufacturer also notified their suppliers that the materials were to be used in a vegan product and needed to meet specific requirements; ensuring open and honest communication.

 

As the manufacturer did not have the resources or space for a dedicated line, the vegan mayonnaise would be made using shared equipment. RSSL consultants therefore visited the site and reviewed the plans for the manufacturing process, identifying potential areas where there was a risk that could impact the validity of the vegan claim. All stages of the process were considered; from the storage of materials, through to decanting and blending, as well as production and packing.

 

The potential serious risk of an egg containing product being packed into the vegan packaging in error was also an important part of this stage of the assessment. Labelling of re-work and the process for applying packaging to the line were identified as key areas for improvement, in order to minimise the risk of misuse of ingredients or cross-packing of product.

 

 

Cross-contamination risk

 

Consideration also had to be given to the risk of cross-contamination through insufficient cleaning of the shared manufacturing equipment. RSSL therefore recommended undertaking a cleaning validation study to assess whether the cleaning procedure was effective at removing the egg mayonnaise from the line and equipment. 

 

RSSL advised on the sampling points for swabbing; focussing on the hardest to clean areas and different surface types. We further recommended the inclusion of both a positive control sample of the egg mayonnaise and samples of the next-made vegan product. A level of ongoing surveillance testing to substantiate the vegan claim was also advised. Having determined that analytical testing to assess the success of the cleaning procedure was needed, RSSL developed and carried out a bespoke cleaning validation study.

Based on our extensive experience, we recommended targeting egg protein using an Enzyme Linked Immunosorbent Assay (ELISA) to assess the risk of cross contamination.

 

Prior to conducting the cleaning validation, we conducted a verification of the chosen ELISA kit at RSSL’s testing facility. The results showed that it was suitable for use with the bespoke sampling plan of the cleaning validation study - see Table 2.

Table 2: Egg ELISA kit verification results

The sampling for the cleaning validation was conducted over three separate days to allow for changes in staff across different shifts. This approach provided an indication of how consistently the clean was performed and enabled conclusions to be drawn from the testing results. The sampling plan included post clean swabs, rinse waters and next-off-the line vegan mayonnaise samples.

 

Table 3: Cleaning validation study results

 

 

The data obtained provided evidence that the cleaning procedures were effective at removing the egg mayonnaise from the production line and equipment, as well as preventing carry-over of egg into the vegan mayonnaise product. Therefore, the risk of cross contamination from egg mayonnaise to vegan mayonnaise on a shared line was considered low.

 

The final requirement for analytical testing was to set up a periodic cleaning verification plan to ensure that the minimal cross contamination risk remained low. This cleaning verification was based on a minimal version of the original cleaning validation study sampling plan and included periodic testing of the vegan product to ensure absence of egg protein.

 

The cleaning validation study and continuing verification sampling plans remain valid until a change in the food production process, product recipe or the cleaning process occur.

 

 

 

The result

 

RSSL’s team of highly experienced food technologists met this challenging client brief by creating a vegan mayonnaise that delivered all the desired sensory and functional properties, as well as a shelf life comparable to the commercial benchmark. Using targeted analytical methods, we successfully evaluated a series of prototypes against key performance parameters and optimised the final product formulation for maximum consumer acceptance. 

 

Our comprehensive risk assessment of the client’s supply chain and manufacturing operation further determined that although the risk of animal-derived cross-contamination on the shared production line was low, further improvements to monitoring and cleaning validation procedures were advisable in order to substantiate a vegan on-pack claim[EE1] .  RSSL’s analytical evidence and recommendations proved instrumental to the successful scaling-up of the initial concept to market-ready vegan mayonnaise. 

Innovative solutions for vegan food product development