There are no simple changes

“Reformulation requires much more than removing or replacing a specific ingredient. It demands a thorough understanding of the underlying science”- Dr Steven Walker.

Dr Steven J. Walker is Director General of Campden BRI. For more information visit

Dr Steven Walker - Campden BRIAs leaders in the field of food science and technology, all of us at Campden BRI know that seemingly simple changes to recipes can have significant consequences for product safety, quality and manufacturing.

Product reformulation has to anticipate and allow for these changes. It demands of manufacturers and their advisers a full understanding of the science of the product and the technology of its production. Anything less than this can pose serious risks.

Salt, for example, has a preservative effect: at appropriate levels it can prevent or reduce the growth of problem microorganisms. Sophisticated computer models can predict the effect on shelflife of changing salt levels. By reducing the salt in ham from 3.7% to 1.9%, for example, the time taken for an observable increase in the level of Clostridium botulinum falls from 22 to 9 days.

So, if salt is taken out some other strategy for product preservation and safety assurance is needed. In other instances, changes may reduce the 'use by' date, thereby increasing costs and potentially increasing wastage.

Whilst very useful, this 'predictive' approach is not by itself sufficient. It would usually be followed with experimental assessment, in which reformulated prototypes are 'challenged' with the micro-organism of concern under appropriate conditions to assess actual microbial growth. The planning, execution and interpretation of such trials demand significant scientific and technical expertise.

Whilst fat does not have a preservation effect, its replacement with a substitute can affect the water available to microorganisms (water activity) which can be important in preservation. Other ingredients influence product pH, which also helps control microbial growth in many products.

Product safety is assured through the process of HACCP (Hazard Analysis Critical Control Point), which helps ensure that hazards are controlled. Any change to a product's formulation or process requires a thorough review of the HACCP plan – to ensure that safety is not inadvertently compromised. This again demands scientific, technical and operational expertise.

Reformulations can also have consequences for the mechanics of processing. While bread is not particularly high in salt, it is part of our staple diet and so contributes to dietary salt intake.

However, reducing salt not only influences bread flavour, texture and appearance, but can significantly increase dough stickiness. This poses potentially major complications for the equipment used in dough production.

Maintaining product quality is another important aspect of reformulation. Some 10 years ago research demonstrated significant consumer resistance to lower fat bakery products: they were felt to be of poorer quality, were more expensive and the achievable fat reduction was small. It has taken extensive formulation trials, in which fat was replaced with starch for example, to establish ways of producing appealing cakes with significantly less fat and calories.

When products have been reformulated, care has to be taken with product labelling, to ensure compliance (for instance with nutrition claims regulations) and to avoid consumer confusion (for example, by not updating cooking instructions).

In short, reformulation almost always requires much more than removing a specific ingredient or replacing it with a substitute. It demands a thorough understanding of the underlying science and technology, and can require significant research and development to avoid compromising product safety and quality.

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Last reviewed: 06 Jul 2009