We recently noticed that our wire-cut biscuit dough hardens very quickly during the cut, causing variations in weight and disassembling the extruder rolls. This seems to happen since we started using a non-palm, liquid lipid (used at room temperature, very low SFC), instead of solid shortening.
Even though I had worked with dough like this before, it is the first time that this behavior causes a machine stoppage. I'd be glad if I could get help in understanding why this occurs (the physical chemistry involved), and what actions could solve or mitigate the issue. The dough is a typical one for wire-cutting, no inclusions.
I know you have a large experience also in other products and as colleagues here already mentioned and you know many details are not specific enought to work on.
My best guess would be that you are on socalled crossing: if dough temperature and mixing intensity are changed you can make from a dough for a deposited/ wirecut product a rotary moulding or sheeting product. Secondly an oil with low SFC at room temperature will not protect your protein by lubrication from hydration. In this case hydration does not have to take place during mixing process, but also happens over time as all things in nature are searching for an equilibrium: that means that the fibres, starches and proteins at first fight to absorb water and over time their water retention/ holding capacity will allow other ingredients to absorb water. Water and dough temperature can play a role in this, as I think you are aware. If it is only recently that this happens I would request from your flour supplier if they have had to change something in milling; e.g. higher damaged starch and/ or more pentosans in your flour. If changing SFC profile is not an option, then emulsifiers might facilitate an improvement as suggested; if it is a consequence of your flour changes it is different.
Bij applying a liquid fat instead of a crystallised fat (=solid shortening) you changed a number of things. Did you use the same dough composition and the same fat? The liquid fat ( I assume it is actually melted fat at high temperature) will crystallise partly in the dough making step and further. The speed of crystallisation is depending on the fat used and on dough and environment temperature and time is also important. This crystallisation (solid forming) influences the hardness of the dough; see also my website: www.fatsforfoods.com/biscuits.
Some companies crystallise the fat before use in house (high investment) or they buy pumpable shortenings.
More details necessary for further support.
Gabrie, fatsforfoods consultant
What is your dough temperature target?
There are a few ways the dough hardens over time but with the facts you provided i can only give you a some general ideas for the root cause
1. Ingredients- flour made from hard wheat or soft wheat flour that may have higher levels of starch damage will accelerate dough hydration and impact dough rheology, lower water levels in dough may be too low and not allow for typical hydration to achieve your desired dough rheology over the course of lay time , lastky evaluate other added ingredients in your formulation that impacts dough absorption (ie cocoa or added starches ..)
2. Formula- assure typical levels of sugar,, fat to flour ratios are achieved
3. Processing watch outs could include increasing dough temperature to allow for softer dough consistency, assuring that you are not over mixing the dough by reducing mixer speeds or decrease mix time once the flour is added, evaluate mixing stages where ingredients are added to allow for uniform dispersion of ingredients and uniform dough hydration. Typically I like to see a three stage mixing process for wire cut cookies.
Normally if you eat the cookie with solid fat and in the same recipe if you replace the oil then this problem is imminent. So for the oil usage please change the emulsifier you use. I suggest Lecithin and Datem combination. Lecithin at 0.25% on WF and Datem at 0.08% on WF. Datem works with Oil very perfectly and definitely deliver the soft bite. If you still have the problem you can add SSL at 0.02%.
Secondly if it is wire cut dropped cookie you can take the dough in soft consistency and try. Also oven Bottom temperature low at initial zones. Do not go for very baking time more than 5 to 5.30mts. Hope you are using normal soft dough wheat flour only (Dry Gluten percentage between 9 to 10%).
Thirdly hope that you are using palm oil origin only. If you are using oil like sunflower oil or other veg. oil or rice bran oil kindly let me know.
Also please try to increase ammonia and ammonia qty and sugar qty please arrive at right combination so that you get right size as well good bite.
Hello, thanks for the replies. The target Dough temp is around 22-23°C (using ice scraps in dough to achieve that, since there is no cold water infeed).
The lipid is not melted, similar to oil behavior, and we cannot change it for now.
Domenico, thanks for the tips. Unfortunately, we do not currently have much resources to improve flour in mentioned aspects, but I will check your recommendations. We tested a water-releasing enzyme to mitigate the issue, but it still occurs.
Do you have SFC data on the liquid fat from the supplier and/or a fatty acid composition. I assume that your liquid lipid has a dosing temperature of about 50°C?
Then I can better describe what is happening with the fat in the dough making process.
Thanks Gabrie, it is dosed at room temperature, it has very low solid content, supplier does not even provide a curve in spec. I already used it in these type of products, but never had this kind of problem before.