20 Sep 12 The challenges for ingredients in foods
Ingredients are of course the building blocks of foods – they combine together to form structures at the micro and macro level. These structures then break down in the mouth to form new textures and release flavours, breaking down further in the body during digestion. The ingredients may undergo physical and/or chemical changes or indeed survive unchanged. Whatever happens, the best ingredients are those that meet a number of challenges in a robust and predicable manner.
In the third in his series of ‘Top 10s’, Leatherhead’s Dr Wayne Morley, Head of Food Innovation, takes a look at ingredients, specifically the challenges that ingredients face when used in foods.
Challenge 1 – Demonstrated functionality in the final product
Every ingredient in a finished product must be there for a specific functional reason, and if this is not demonstrated then the ingredient should be removed or replaced. This means that ingredients should be replaced rather than just added to an already complex formulation, and that significant reformulations should start from scratch.
Product developers should research ingredient functionality prior to any reformulation activity, and the functionality is especially critical if the ingredient is highlighted in any way on the product label.
Challenge 2 – Easy to use in the factory
The best ingredients are those that are easy to use in manufacturing processes. This means that they are supplied in a convenient physical form, preferably a free-flowing powder, although relatively low viscosity liquids are also convenient. Less so are gels and suspensions.
The ingredient should dissolve easily in water (preferable) or oil, and be supplied in an appropriate unit size such as a 25kg sack. For bulk ingredients, larger units such as 1T bags should be available. Finally, the ingredient’s packaging should be easy to open and dispose of.
Challenge 3 – Cope with the other ingredients
Ingredients, of course, do not exist individually in foods so it is important that the desired functionality is not affected by the presence of the other ingredients. For example, they should be easy to combine with the other ingredients and the order of addition of the ingredients should not affect the functionality.
Many products contain high levels of salt or acid, so the ingredients should be able to cope with these as well as not undergoing any unexpected reactions.
Challenge 4 – Natural/clean label, or can be labelled as such
You may consider your ingredients to be ‘natural’ or ‘clean-label’, but ultimately it is all about the consumer perception of the label declarations. In particular, an ingredient will meet this challenge if consumers recognise it and appreciate the functionality. Consideration should therefore be paid to the use of ‘E-numbers’ and ingredients that contain the letter ‘x’.
However, it is not just the ingredients declaration that matters, as the ingredients may be referenced elsewhere, such as in claims statements or allergen declarations. Finally, reductions in salt, fat and sugar are always required even though these ingredients may be considered to be natural.
Challenge 5 – Cost-effective at the level used in the final product
The headline figure for any ingredient is the cost per tonne or cost per kg but, of course, many ingredients are used at very low levels or are diluted before use. It is therefore a good idea to calculate the cost of an ingredient at the level used in the final product, and use this information to focus any cost saving activities.
The savings from any ingredient reductions or replacements are of course welcome, but this work should start with those that carry the highest cost in the product. In practice this often means fat and sugar.
Challenge 6 – Stable to the end of shelf-life, or at least until the product is consumed
The shelf-lives of foods range from days to years and the ingredients should be selected with the particular requirement in mind. The storage conditions themselves vary greatly, especially temperature from frozen (-18°C) to tropical (40°C), but also humidity. Temperature cycling can be a particular problem, and we know that many products will be abused in the supply chain and retail environment, as well as by consumers.
The best ingredients will be robust to these variations and will also allow accelerated shelf-life protocols to be applied.
Challenge 7 – Not present too much of a microbiological challenge
The first requirement of any manufacturer is to produce safe and stable foods and the microbiological status of any ingredient depends on many factors, including the sourcing, manufacturing protocols, packaging, and so on. Some ingredients may be considered to be inherently safe and stable (e.g. acids), but problems can still occur.
It is advisable that the microbiological status of any new ingredient is in-line with the others used in the formulation, and of course robust specifications are important. Finally, a certificate of analysis, or preferably a certificate of conformance, is required for each delivery and/or batch of an ingredient.
Challenge 8 – Allow efficient product scale-up
Efficient scale-up is one of the holy grails of product development and ingredients have an important role to play. The work will start in the development kitchen or pilot plant and the ingredients must perform with these types of equipment, as well as in the factory.
In practice, this means that they should be robust to differences in mixing time and intensity, and absolute temperatures as well as heating and cooling rates. In addition, the ingredients for kitchen-scale development may themselves have been prepared in small quantities using pilot facilities. Obviously the quality should be the same as the production material, and the shelf life should be long enough for the product developer to store for some time. Ambient storage is generally preferred, then frozen and finally chilled.
Challenge 9 – Be well specified and traceable
All ingredients should be supplied with robust specifications that form part of a dossier, along with specifications for the packaging, manufacturing process, and the product itself. The ingredients specifications should only contain parameters that are important and can be measured, with realistic upper and lower limits around a target value.
These aspects are of importance in trouble-shooting activities which often require traceability all the way back to the manufacturing arrangements for specific ingredients. The suppliers of these ingredients should be able to supply this information quickly, and of course it is desirable for any product quality issues to be traced back to some other aspect of the product mix.
Challenge 10 – Survive the manufacturing process
The manufacturing processes for foods are wide and varied, involving many processing steps, equipment types and technologies. Typically these will require the ingredients and products to be subjected to heat and sheer forces, as well as being held in storage tanks and transported along pipework. The materials will undergo various physical and chemical changes, and may be totally unrecognisable at the end of the process, when compared to the beginning. The ingredients must survive the complete process and emerge with the desired functionality intact. This does not necessarily mean that the functionality is unchanged, but that any changes are reproducible and desirable.
It is worthwhile considering how your ingredients meet these challenges. This can be done by simply counting up how many of the 10 are met and how many are not. You can also apply weightings if you consider some challenges to be more important than others. If you are an ingredients supplier, then your customers may well be carrying out this exercise themselves so you will need to be prepared for the inevitable questions that will arise.
There are of course many other challenges, some of which may be specific to the food industry sector that a manufacturer operates in. These include the regulatory environment which can vary greatly depending on the application; geography, and the importance of labelling accuracy when considering allergens.
Removing or replacing ingredients can have a significant impact on the quality of the product, so the importance of robust consumer research cannot be overstated. And maintaining the safety and stability of the food is the first requirement of any manufacturer as outlined in Challenge 7.
Source: Leatherhead Food RA: www.leatherheadfood.com
Other articles by Wayne Morley