Maintaining ingredient quality in an uncertain world

Faced with COVID-19, Brexit and volatile global tariffs, the need for manufacturers to plan for supply chain disruption has never been so important. But switching ingredient suppliers can have major implications in terms of product performance, quality and consistency. Dr Robert Griffiths, Lipids Technical Expert Lipids and Daniele Leonarduzzi, Physical Science Technical Expert from Reading Scientific Services Ltd (RSSL) explain how the right analytical testing strategy can not only help to mitigate these risks but also resolve any subsequent processing problems.

Core criteria​

Whatever the driver for change, sourcing ingredients from a different supplier is a challenging prospect. Not least because any differences in the physical properties and chemical composition of an ingredient may alter key characteristics in the finished product, such as stability, taste, texture or visual appearance. Such an unwanted outcome could potentially compromise quality of the products; consumer preference and ultimately damage market share.

The goal, therefore, is to ensure that the profile of the newly sourced ingredient meets the same exacting standards and delivers the same end result - and this is where RSSL’s knowledge in ingredients and analytical testing is an invaluable asset. Working in partnership with food manufactures around the world, we provide expert guidance and help clients to ensure ingredient quality is consistent across the supplier roster. This means focusing attention on a number of important aspects.  

Any variation in the way an ingredient performs can have a direct impact on the quality of the finished product. So analysing functionality (physical and chemical properties) is essential in order to ensure the newly sourced ingredient will perform as expected, both during processing and in the finished product. 

Oils and fats, for example, can have a significant impact on the texture of finished products and the balance of solid and liquid fat present in the ingredient can be a key to achieving the desired result. Getting it wrong can have serious consequences. Too much solid fat, or high temperature melting fat, and a product can become overly hard, difficult to spread or feel waxy in the mouth, while not enough may mean it melts too quickly in the hand or struggles to hold its form or can cause oil to separate out during shelf life. Not only that, if the product starts to solidify during processing as a result of too much high melting fat, this can lead to blocked pipes and tanks and costly downtime for the manufacturing line. By assessing the physical and chemical properties of oils and fats from a new supplier, or when using new fat ingredients in a formulation before application, RSSL can ensure the ingredient matches the required compositional profile and physical properties and avoid problems further down the line.

Equally important is the need to verify that the specified functionality of an ingredient at the point of application is the same as when it was first produced. In other words, has it been altered during transit or storage? High temperatures or humidity can have a major impact on ingredient quality. So too can the physical storage method. Powders, for example, are often stored in sacks, but that may encourage unwanted behaviours such as the formation of lumps and hard cakes. Equally, some materials may be more friable (likely to crumble or break down into smaller particles) during transit, which may ultimately affect their performance in use. RSSL’s ability to measure key parameters - such as ingredients flowability, their particle size and water uptake in defined humidity temperature conditions - means we can determine whether an ingredient mix remains homogenous throughout storage and define the optimum environment for ingredients from the outset.

There are a number of ways that a product can fail during shelf-life. Texture, colour and appearance can all change over time, but one of the most influential factors in terms of consumer acceptance is taste and the absence of oxidation / rancidity; the unappealing tastes and flavours generated by the oxidation of oils and fats. This means that the stability of oils and fats and how likely they are to oxidise over the defined product shelf-life is a major consideration.

Different oils and fats can vary significantly in terms of stability, which can be further enhanced by the addition of antioxidants; RSSL can provide a detailed picture of how an individual fat ingredient (or antioxidant addition) will perform in a particular product application. Chemical analysis can provide information on the composition and quality, which has a significant impact on stability, and can therefore give an initial indication of any risks during shelf life, while accelerated oxidation tests enable us to provide quick guidance on likely shelf-life. These accelerated tests are particularly useful in product development or troubleshooting when quick answers are required to determine the optimal fat ingredients to use in the formulation. Alternatively, storage studies can be carried out, where the ingredient, or finished product, is kept at ambient or above room temperature and tested over time to assess the level of oxidation / rancidity. Taking it to the next level, we are also able to look at which specific compounds (such as aldehydes and ketones) are causing the characteristic rancidity off notes and flavours that are perceived sensorially as the product starts to oxidise. In fact, we are getting to the stage where our extensive analytical data could potentially reduce the amount of sensory evaluation that needs to be done during shelf life assessments.

Beyond ingredient quality, these tests have wider benefits in terms of cost-benefit ratio. Although higher quality ingredients generally offer a longer shelf life, there is little value in paying a premium for an ingredient that is stable for three years if the product in question has a defined shelf life of just three months. RSSL can ensure the optimum balance is achieved.

Verifying origin and authenticity is important for many ingredients - particularly those that command a premium price. After all, no one wants to pay for a high-quality product only to find out it contains cheaper or sub-standard ingredients.

Perhaps one of the most well-documented examples is olive oil, which has long been a target for adulteration. So much so that extra virgin olive oil grade is subject to more than a dozen analytical tests to fully authenticate its credentials and a dedicated EU regulation to substantiate labelling claims. Many of these analytical tests can be used to assess authenticity of other premium oils and fats, such as nut oils. However, this issue is far from limited to one ingredient category and RSSL can adapt its testing methodology according to each ingredient.

In the case of coffee, for example, we look at carbohydrate profile to determine whether it has been bulked up with something other than coffee, such as chicory. Within the natural products space, echinacea is a well-known herbal ingredient but can be found in two varieties echinacea and purpurea, each with a different profile and functionality. Analytical methods enable us to assess the quality of herbal ingredients and differentiate between herbal species.

Trouble-shooting tool​

Although analytical techniques should ideally be used to verify every ingredient before application, the unpredictable reality and pace of food manufacturing means that this is not always possible. If problems do occur, these techniques are just as relevant because they can help to explain why the end product is no longer meeting expectations. We understand the far-reaching impact that ingredient quality can have on product performance, so the first question we ask is whether there have been any changes to suppliers or ingredients.

Even when the ingredient specification has not changed, there can still be reasons for a drop-in product quality. Seasonal variation in natural ingredients, for example, affects their composition and functionality. Analytical profiling, such as finger printing, can then help to establish if there are any notable differences in the current batch.

There may also be an argument for checking that the analytical methods used by supplier and manufacturer to measure an ingredient’s properties are aligned. We often find that there are significant differences in approach or technique - despite both parties working to the same specification - and this naturally impacts product consistency and quality. RSSL’s expertise has even been employed to help resolve legal disputes. In one particular case, our analytical results were able to demonstrate that the source of a food quality issue was not related to the factory’s production methods, but could be traced to a particular ingredient coming in.

So whatever the issue, from working with new suppliers, resolving product quality issues or developing new products, RSSL’s knowledge in ingredient functionality and processes and analytical capabilities have a valuable role to play. For further information about how RSSL can help you to ensure the quality of your ingredients please click here​ or contact us on radhvevrf@effy.pbz​ or +44 (0)118 918 4076.

The Covid-19 situation has put a considerable amount of pressure on global food supply chains, creating challenges around ingredient sourcing In this webinar below, RSSL’s Food Safety and Quality Consultants Barbara Hirst and Jessica Sage, share their experience and provide guidance for manufacturers and retailers to use when considering new suppliers.