As food industry consultants providing technical solutions to Snacks, Bakery and Confectionery players, we routinely come across plenty of questions on flavors and flavoring systems. Many of these queries stem from practical and operational challenges that our customers face during the flavoring application process. Here is a selection of the top rated questions that were posed to our experts during the recent Knowledge Series titled Flavors and Applications. Food industry experts Harsh Koshti from Kerry and Kaushik Malpani from SV Agri took some time to answer these.
One of the key insights for us was to learn how a delightful customer experience is rooted in a multitude of factors that include not only the flavor, but also the underlying product and application quality.
- Underlying product
- Application quality
For example, a popular trending flavor or seasoning, applied on the wrong product may not leave customers with a satisfactory experience. Thus, flavor that tastes just right for potato chips may not be the ideal one for extruded snacks! Similarly, a great flavor paired with a good product but with sub-optimal application quality – either in terms of quantity, consistency or coverage, will leave a sour taste in the mouth (pun intended).
Therefore, it is heartening to note that our users’ questions tended to look at these topics not merely in isolation but sought to understand the unique interaction between flavors, products and flavoring equipment. Today’s consumers are demanding and discerning and merely getting one of the above right is not going to cut it. Its only when they all come together that magic happens!
Without further ado, below are the key Q&A.
1. Are there any ingredients or flavours that might be more prone to lumping? Or is it just a function of humidity only?
Any hygroscopic combination would lead to lumping. A lot of flavours in South East Asia tend to use sugar as a base which is certainly hygroscopic. That said, there are certain ingredients that can be used in seasonings and flavours to avoid caking or lumping or premature granulation and to resist excess moisture uptake.
2. Is there any specific characteristics of seasoning that we must consider in order to get accurate dosage?
When it comes to the key characteristics of seasonings, particularly as it relates to their performance on flavouring systems, flowability and granulation are the two most important ones to look out for. If we have very different levels of granulation in a flavour, it may lead to choking of the nozzle at certain points.
The characteristic of flowability is equally important. When one picks up a spoonful of flavour, one always knows that it has a specific amount of salt, sugar, turmeric, cumin, or caramel etc. However, when lumping happens, the consistency of the lump can change entirely. It could be a lot of salt or a lot of sugar in different portions of the flavour and if this goes on a particular product, customers will not get the same experience bite after bite. So you might like to have a savoury chip and you might find a lot of chili, wherein you wanted more tamarind and chili together, and it changes the delivery of the experience. So that’s the direct impact of what happens with lumping. In other words, when there is lump formation or poor flowability, you destroy the localized design, and there is dominance of just one of those components of the flavour. This issue of flowability tends to get exacerbated for certain ingredients such as sugar based flavours which are hygroscopic in nature and have a tendency of forming larger and larger lumps as humidity increases.
3. Do flavours need to be considered in conjunction with texture and microstructure of product i.e. would some flavours go better with certain textures than others?
This is correct. One size does not fit all. A flavour that would work fantastically well on potato chips may or may not work on extruded snacks. So it must be horses for courses and knowledge around science and chemistry of the taste and flavour is very, very important.
4. What is the right temperature to apply slurry on a snack product such as a Nachos?
There are several ways to answer this question.
First, one needs to know what the volatile oil content in the flavour is. We don’t want to exceed temperature thresholds in such a manner that we start losing volatiles within the flavour.
Second, the slurry temperature is also a function of what allows the seasoning to dissolve in oil. In normal circumstances, we use a temperature of 40-45 degrees Celsius. This can, of course vary, depending on the kind of seasoning. Dissolving the seasoning in slurry is important. So, getting the temperature optimum in the time when the batch is getting made – perhaps a 10 or 15 minute cycle, we’re able to dissolve as much as required, so that we can have a consistent solution.
Last but not the least, it is also important to note that the temperature of the incoming product is crucial when the flavouring application is being done. If it’s very warm, then it would not leave after notes, which is part of the product design. On the other hand, if the product temperature is too cold, then it would not have much capacity to absorb the flavour.
In summary, slurry temperature is a function of dissolution (oil dissolvables) so that the resultant slurry is smoother and more consistent. In addition, getting the temperature of the product right is also important so that flavour absorption can happen in an optimum manner.
5. If there are 2 products with different shapes, say ball shape and stick shape, to be coated together, can uniformity of seasoning coating still be achieved?
In situations such as these, when you have multiple bulk densities with different flowabilities, then seasoning drums with screws are very useful – wherein you control the amount of time that product is spending inside the drum. One also needs to know exactly how much cone angle is available over what spread of the drum, so that it is covering the right amount. While this is not impossible to attain, it certainly is complex because bulk densities are different. The geometry of different shapes is different and therefore tumbling is going to be different. The best way to control the outcome is to control the dwell time in the tumble drum. And therefore, you go in with screws and portions. The idea is to make the entire product flow like modules. In essence, you convert full seasoning continuous drum to multiple batches and the entire screw moves the whole batch, batch after batch, portion of the portion within that drum. And that’s how you will be able to achieve much better coverage.
6. What is the ideal angle for tumbler in order to get uniform coating on the product?
There is no ideal angle, because every product has particular fall angle and a particular tumble angle. For achieving uniform coverage on all faces of the product, we want the product to flip from one side to another. Let’s say for potato chip, for example, we want the face 1 to get flipped onto face 2. So that is called the rise angle and the fall angle. When we rise it up, you want it to tip down. And when we’re tipping it back, the angle is decided in such a manner that the flip happens. Different products have different flipping angles, and it is a function of the bulk density and the amount of product that is going into the drum. So, once we know these two aspects, we run tests and simulate for the geometry and bulk density for those specific products and determine the most ideal combination of rise and fall angles. Some of the common combinations are 45/45, 60/40, 60/30, 30/70, 30/60 etc. Additionally, it could be different depending on how fragile the product is. We don’t want the product to have a very steep fall because then it could break up into smaller pieces and eventually rejected in quality inspection. So, it is a function of a combination of the above factors and depends on the product itself.
7. Does the level in the seasoning hopper impact the accuracy of dosing?
Yes, it sure does! For this, we recommend that you run a flat test on your own. Fill the seasoning hopper fully, collect some material for the next maybe 30 seconds, and then keep taking the weight at every 30 second interval. As the volume keeps coming, you will observe that the amount of seasoning you capture in each 30 second interval keeps changing. This is because gravity plays a part on the fill volume inside the screw. As the hopper level keeps coming down, the fill volume keeps changing. So unless you’re changing the screw or have a method to know what has changed and take corrective action, it will have an impact on how much seasoning is dispensed.
8. Can you give an example of what kind of seasoning that is most suitable to be applied in oil slurry system?
Normally, it is a function of the texture of the product. If you see that the porosity is sufficient for both the oil and flavour to go into the product, you would use slurry. For slurry, you could use a decent portion of seasoning that is oil soluble, if not entirely. All of the seasoning would not be oil soluble because it might have many ingredients such as roasted flour or roasted starches as base, all of which are not oil soluble. That’s why, a slurry is always a colloid. If you take a slurry and allow it to sit on a glass, you will see a density separation very quickly. So, if you can have a consistent colloid for a larger range of time and still deliver the taste, that’s the balance which you should look at for selecting what kind of seasoning would work. It would impact the notes that you’re looking for.
9. Do we need to control the particle size of seasoning in slurry when using slurry spraying method?
Typically, seasoning already has a particular granulation. This means that flavour is supplied by suppliers to a particular specification of granulation. Getting the mixing right here is very important. If the normal practice is to dump the entire 10 or 15 kgs of flavor in 2-3 batches of 5kg each and there is not enough agitation for it to mix completely, then lumping starts happening. As one can expect, lump formation here is not a cause, but a consequence of improper mixing. In our experience, in 9 out of 10 cases, the problem gets generated in the preparation kettle. So that’s the larger and more important part.
In rest of the choking cases, lump formation and nozzle choking can result when the temperature is not right. So even if the mixing and agitation was done well in the preparation kettle, but if the temperature profile has not been maintained, i.e. if it was colder or warmer than required, then one ends up changing the properties of the slurry. Most of the times we see that temperature control is in place, but in some cases, if one is not careful – for example, if the impeller pump has not been cleaned properly, one ends up having extra heating in the slurry. And this results in choking in the front – despite having cleaned up the choke! The key to solving this problem is knowing where the problem originated. In this case, during rotation inside the pump, some warming has happened and that warming itself will cause more choking to happen.