The full Leosmak training session, chapter by chapter

So, the first thing to understand is that the machine you have or you are planning to have is basically two in one, so you have also a freeze dryer here and a vacuum dryer here. We differentiate this by calling the first option so to say a normal mode and a second one is a "sweet mode" - how we call it. So, either you always put the machine into normal mode or in "sweet mode" and depending on this you will have the normal freeze drying process or the vacuum drying. And what is the difference basically between the freeze drying and vacuum drying?

There are two physical processes lying beneath each of them: so, the freeze drying is basically based on a sublimation. Sublimation is what happens high in the mountains, where you have low pressure and then the solid water called ice is starting to vaporize, so that it skips the liquid phase and becomes vapor immediately. This is the sublimation. And the machine we have here to my left - this is LEO-030 machine, this is the smallest from industrial machines.

This machine has an aim to do the same process in controlled environment. The second way to what we called a vacuum drying - or sweet mode in our menu - which I will show you later - it's based on adsorption. And adsorption is simply vaporization of water in lower pressure. So, in both cases we have low pressure but in sublimation or normal mode of normal freeze drying we have solid ice becoming vapor, while in vacuum drying we have also low pressure we call it also sweet mode here, yeah, or vacuum drying - but in this case water even if it's in liquid stage becomes vapor.

So these are two differences in freeze drying: we start from ice, we go to vapor; in vacuum drying we start from liquid water even and we go to vapor. And these are very substantial but important differences to understand. Let's

Let's talk first about the connection of the machine so that we address your concerns probably about how to use it. Basically all our compact models and smaller industrial models like LEO-030 - they are built as plug and play principle, so you simply need to connect the machine to the power, then you need to connect the drainage pipe which we will show you just in a while how to do this and basically this is it. So, the power, the drainage pipe for water that is gathered after each cycle - and that's it. Then you simply turn it on, nothing more to be done.

In LEO-030 model we have here you can see there are two major buttons on the front panel: one is red, which you can hit at any time just to switch the machine whenever needed and the green one, which is responsible for turning the machine on. So now I will turn the machine on, so you can see how to do this: first I will switch it off and now you can see that I'm pressing the red button just with a small turn and push the green button to start. Now the menu is loading and when we start to see the menu, we have basically the four major functions of normal mode which is - you remember already - responsible for freeze drying or for the sublimation actually, as we call this process in physics. And you have three points out of these four responsible for operational stage of the machine, and the first point which is responsible for servicing like or service stage as we call it.

Basically, you need to understand that first three points are where actually this magic happens. For three points called freezing, sublimation and drying you have the product inside; for defreezing, the last point you have - no product already inside and the defreezing is made with no product inside of the machine. This is important to remember. When we

When we turned on the machine, it would be really helpful for you also to connect it to Wi-Fi, because you can monitor basic parameters of the machine online using our application which is to be downloaded from app store basically on your phone. Yes :) So, there is no problem with monitoring the device remotely from any point around the globe. It is possible to connect different phones to the device to see this device. It's done in a very simple way.

What you need to do - you need to enter the Wi-Fi settings there, you need to enter the SSID or the network name, then you need to enter the password and then you just press the save button so that device will connect to your Wi-Fi network, local Wi-Fi network. It's important to remember, that these units - these are industrial units, they work only with 2.4 GHz as a broadband you have in your Wi-Fi network. It will not work with dual band, which is called the same, it is not going to work with 5 GHz network connection, so only 2.4 GHz is going to work here. Well, when the device is already connected, - you have in the same Wi-Fi settings menu - you have this QR code, which you need to scan from your mobile phone after you download our Leosmak application.

Then the device and your phone will be connected and you can see three basic parameters running also on the screen here, the same is reflected in your application, so that you can monitor if device is working properly. There are three basic parameters to monitor all the time and our primary goal as an operator of this device is to monitor how these parameters are going in each stage. There is a very important table in our operation operational manual and basically it's located on page 17, so I encourage you to stick to this table later, but you will also have the general feeling on what parameters should we expect in each point of process going, so that we know that everything works properly and we can have the very nice result in the end. So, let's

You've seen a lot. Of course you can probably have a lot of questions. Now we will go to further discussion of tips and some points and guidance on what to do if this would be the next stage of our communication. But before we do that, I also promised you at the very beginning, that we will make this trial start of the machine, so that we can be sure that your machine arrived properly; well, that there was no significant damage to the machine during transportation.

Because unfortunately, this happens - these are heavy machines, heavy equipment and severe vibration can damage some inner components of the machine, so after your unpacking of the machine the first thing to do would be of course to listen to this video and to have some basic training and understanding of the process. But also you would like to do the initial test of the machine and we will do this together with you now. When we have the normal mode, what we need to do is to program the freezing to zero hours by disabling the auto mode, pressing "save" button and now, by closing the doors, we are ready to run the test. So, when we press the start button, the freezing stage will be omitted, because this is what we've done - actually we programmed the freezing to zero hours and now it will start from sublimation directly.

And in sublimation, as you remember, it's important that we start getting low temperature levels on the ice traps, desired temperature levels on shelves, and low pressure. And please do this test for approximately 15 to 30 minutes - it will be enough for your freeze dryer to reach operating levels of pressure so this would be 350 pascals or less. It will be enough for your freeze dryer to lower the temperature of the ice traps as low as possible and it will be enough for your freeze dryer to start heating the shelves. So, press the start button and wait for 30 minutes and see for the results.

If you don't see the desired levels of these three parameters in your device, please contact us, we will help you of course immediately. Okay, so from my perspective this will be the basic set for today. Now, I invite you to join me to the discussion of tips, on how to process your product in the most effective way so that you are really satisfied with the freeze drying technology that you've just acquired or are planning to acquire. I'm standing

With freezing in normal mode, I repeat - we talk about sublimation here all the time - in freezing it's all about the duration and that's basically it. When we enter the freezing, we can disable the auto mode, as I do it now and then you can change the duration of the freezing from default 4 hours to even zero hours. This is important, sometimes you want to skip the freezing so that there is no freezing, because you have for example pre-frozen product and you don't need to make freezing here at all, just to save time and to get your results faster. In this case you can program the freezing stage to zero hours but you can also make it longer.

Why is that? Because some products like with fat, for example, with big amounts of fat in some meats, in milk even - they can demand longer period of time to be properly frozen to minus 20 deg. C or less, to get the best result, because the deeper the freeze we apply for our product here, the better from point of view of effects, cause ice will be really small in terms of crystals. And the deeper the temperature we have here, the lower the temperature we have here, the better of course.

The machine will do the best it can, basically, taking into an account the compressor and everything we have around. So, you don't need to worry about the temperature, but you can control the duration here. So, please remember, that for some products you can, for instance, make this process longer than default 4 hours or you can also for example set the machine only to 1 hour if you have your product prefrozen, but you are unsure if it's well frozen or if it's had not started to melt while you were unloading it or loading it into the machine, so in this case basically you can make the process only for 1 hour, for example, just to have this effect of even freezing of the whole product inside of the machine. Okay, one more important button you have here in freezing stage is called "Shelves cooling down".

When I hit this button, the machine will start cooling down the shelves for approximately 15 minutes. This will allow to cool down the shelves to minus 20 deg. C approximately in this time, and this gives you a possibility to load pre-frozen product without being worried if it will not start to melt. Because in normal mode, in sublimation, basically liquid water is our enemy - we don't want to have liquid water before we start the sublimation in this mode.

Okay, so it's important to remember, that you have basically frozen product before you start sublimation, otherwise the effects will not be that good. So, when this cooling down of the shelves will be completed, you can load the product, and then you can simply close the doors. Do not put too much force when closing the doors. Of course, if you don't do the cooling down the shelves and you freeze your product inside of the freeze dryer, you will close the doors earlier and in this case also please avoid too much force.

You just need to be certain that doors are really stuck to the sealing, which we have inside, but you don't need to over-press it or too much force is not recommended definitely here. Let's move

Let's move to the sublimation stage. What do we control in this point, when we disable the auto mode, it's clear that we can control the temperature of the shelves and we can control the duration of this stage. By default it's set respectively to 40° Celsius and to 30 hours in terms of duration. You can change this.

Of course, the rule is, that for example for some products, which contain some big amount of vitamins, proteins that are important to maintain for us - you will basically set lower temperatures, like for example 20° C or 30° C, because, please remember, that most of the proteins start to disintegrate after 40° C. This is not a coincidence that we, as human beings, will basically avoid the temperatures of 42° C plus, because this is basically deadly temperature for us; it's the same for our product inside of the freeze dryer. So, if we have product with some delicate structure, delicate substances inside, we would certainly set lower temperatures for this stage. One important thing to remember is that when sublimation starts, the vaporization will be very intense, so another reason to put lower temperatures for sublimation stage would be to protect your products from "explosion" as we call it - from inside.

This is the same effect you have when you have the mineral water with the bubbles coming out after you open it up. Because when you do this, basically what you do for the water inside of your mineral water bottle - you simply lower the pressure there and this allows the gas to come from the water to the surface and it's the same with the product inside of the freeze dryer. So, if we have basically big amounts of air trapped inside of your product and we lower the pressure very fast, then it will end up in such a process that basically the tissue of this product will be damaged from inside, because of all this air coming out. So we want to have a properly frozen product here, which is deeply frozen and we want to have rather lower temperature, especially in case of delicate products that you can have.

Remember, some probiotics, prebiotics, something like this - in case of such products you will definitely avoid temperatures that are higher than 35° C. Later we can move on to the next point, which is called drying. From technical

From technical point of view there is no difference between drying and sublimation, we have two different names only for the reason that you can set higher temperatures in the final stages of your process and you need somehow to program this. For instance, you can set the sublimation for 30° C and then you can do the drying for 35° C or you can do 35° C for sublimation and 40° for drying, or 40-45, whatever. Some people differentiate this, some do the same process all the time, so it's possible also to do only sublimation at one temperature as you wish. This all depends on type of product you have, how it is cut, if it's sliced, if it's prefrozen, if you have bigger shapes of this product or you have thin layers of this product.

You will have this feeling with a time run. All these recipes: of course we will be also sharing these recipes with you, but in the end of the day all you want to have when the drying process is done, is that your product is from 1 to 4% - this is an industrial standard - in terms of humidity it has inside. We will show you later in a while, how to do the test for level of humidity, we also can provide you with special tools to do this. These are not so expensive tools to have and nice to have, so that you can check the quality of your final product to be sure that you provide this 1 to 4% of humidity of your product in the end.

So, when the freezing, sublimation and drying stages of your normal phase are completed, there will be a screen here saying that you can unload your product already. The freeze dryer will wait until you come and physically press the "unload" button; until that moment it will maintain low pressure and very low temperature on the ice traps so that the ice, which is caught to these pipes, special pipes inside of the freeze dryer - that it is not starting to melt back on your product. Of course, this is something you want to avoid. And be sure, that nothing bad will happen with your product, until you come and press the unload button.

So, if, for example, your product is completed, the process is finalized in the middle of the night - don't worry, you can come in 4 hours, in 6 hours, 8 hours, 10 hours, whatever - and then press the unload button and unload the freeze dryer. The defreezing

The defreezing menu looks so, that you can control the duration here and you have two additional points in this menu here, which is open air in port and open liquid out port. When would you like to use these? The "open air in port" you will use in such circumstance that for example you have stopped the process in the middle of sublimation, for example, so you have very low pressure inside of your freeze dryer and you physically will not be able to open the doors, until you let the air in. So, you can open the air input from this menu here and then the pressure will be evened with atmospheric, which is - I would like to remind you - approximately 101.300 pascals, yeah, like 101300 pascals - this is normal atmospheric pressure approximately.

And until you reach the same pressure inside of the chamber it will not be open, it will not be possible to open the doors because of the difference in pressure so that there will be force pushing on the doors from normal atmosphere and you would need to use too much force and power to open the doors, so basically you need to wait until the pressure is even and then you can open the doors. There is also a mechanical way of opening the doors in case there is no power, for instance, right, because this is something that can in some emergency circumstances happen. So, in this case there is a special valve which you can open mechanically at the back side of the industrial freeze dryer and also there is a special tightening screw, so to say, on the vacuum pump in compact freeze dryer, which you can open to let the air in case you have no power supply, for example, for a couple of hours. There is no possibility to open the doors electronically.

The "open liquid out" port is something you use when you do the cleaning basically. So, please remember not to open this when you have the drainage pipe and hose in, for instance, some kind of a bucket, filled with water when there is a low pressure inside of the chamber. This is a very popular mistake to be done here, so don't open liquid out port from menu here unless there is normal atmospheric pressure inside of the chamber. Yeap, so it's important to remember about this.

Of course, it's possible anytime but, if you do this and you simply open the water out port with the drainage hose inside of the bucket with water, it will simply suck in the water inside of your chamber - not nice thing to have. I just

I just want to warn you that you need to be careful about this. There are three parameters to monitor as I mentioned. As we already discussed all four points of our normal menu here, let's go through the parameter levels you would like to expect in each stage. So, for freezing the normal atmospheric pressure is still okay to have here, because vacuum pump will not be working in freezing stage.

The only thing that will be working, is a compressor that generates basically low temperatures for us, so in freezing we will be hunting or expecting to have the low temperature on shelves. This is it. Nothing more is important for us, we don't need to bother if the ice traps are at higher temperature or lower temperature - it doesn't really matter. The sublimation and drying, as I mentioned - these are basically from point of view of mechanics of the process - these are the same.

So, in sublimation and in drying it will be all about low pressure, it will be about reaching the desired temperature on shelves that you programmed here: either 40 deg. C or 35 deg. C or 30 deg. C, whatever; and you will also need to see low temperature of the ice traps here.

Why is that? Because when you do the sublimation, when the water molecule escapes from your product, - it will, by physics, - it will definitely look for the coolest place around the space and it will stick to that place. This is what we do in sublimation. And in drying we lower the pressure so that water starts to vaporize: from solid ice it becomes vapor and then it will stick to the ice traps on the side or in the back wall of your freeze dryer, depending on the freeze dryer architecture and its construction.

Please, remember that for sublimation we want to have as low pressure as possible inside, as low temperature on the ice traps as possible, preferably -30 - -35 deg. C and then we would like to monitor the temperature of shelves so that we are sure that our product will be heated evenly to the desired temperature. Operational levels of pressure should be 350 pascals or less. Please, remember about this.

This is the threshold that we use in our equipment here: unless you have 350 pascals of pressure inside of your chamber, the heater will not start to work and shelves will not be heated up. The operational levels of sublimation and drying, that we have here would be approximately 200 pascals, 100 pascals or less. In initial stages, when the vaporization is intense, you will have 250-270 Pa, this is okay. If it goes less with a time run - this is a proper way to have.

I would expect that for, example, in most of our freeze dryers you will have approximately 150 or 100 pascals in the final stage of drying. As for the defreezing, you can choose this defreezing after you have done your cycle. Please

Please remember, that your chamber is clean and without any water or ice inside before you start the next cycle. This is very important, because if you are trying to save your time here by leaving some ice on the ice traps - this will simply damage your next batch and this is it. It's not the fault of the machine - it will be unfortunately your fault, that you allow this ice to be there in the chamber before starting the new cycle. There is no water or ice allowed before starting new cycle from point of view of quality of the next batch.

It will not damage the machine of course, but the problem is that when you leave some ice on your ice traps before doing next cycle - it will be melting, for example, during the freezing stage or when the sublimation starts until the pressure drops to desired levels of 350 pascals or less. This ice will be boiling, as we call it, so basically your next product, your next batch will be influenced by this additional humidity that you have in the chamber and it will be - well, simply a bad result for your product in the end. Please, avoid leaving ice or water inside of the chamber. It should be clean and dry before the next cycle - this is why you have the defreezing stage here and you always need to apply it.

Of course you also can skip it and there will be such a possibility in your menu when the process is completed, so you can skip the defreezing stage and basically in this case you can simply leave the freeze dryer as it is with opened water out port, for example. It will simply defreeze from the normal conditions in your room, right. If your room for example has plus 20 plus 21° C this ice will simply melt in 6-7 hours by itself. This is basically it in terms of operating of the normal menu.

You also have the delay start function here, which allows you to put some products inside, close the doors and make for example a delay so that the whole process will start in the middle of the night if you wish. This is useful in some manufacturers, for some manufacturers, for some processes - you can use it, for example, when you do the candies: probably this can be helpful. But with most, with majority of normal products delay start is something that you will use really rarely. Although

Although it's nice to have it, of course. Okay, let's move to the sweet mode now. When I enable the sweet mode, as I do it now on on my screen - what we can see is that basically naming of all the stages changed. And then we have preheating, vaporization, cooling and defreezing, which you already know.

Why is that? Because as you remember, as I mentioned at the very beginning - now we are already in mode of vacuum drying, so this mode here allows us to do basically products, for example, that don't have too much water, like candies and sweets. That's why we call this mode a "Sweet mode". When we set parameters for the sweet mode, we determine the temperature that we want to have on the shelves in the beginning, because if we talk about candies, what we want to have is to make them soft before we lower the pressure.

With candies we want to have such a situation, that in preheating we soften the candy by adding temperature to + 50, + 55, + 60° C - depends on the type of candy you have. Then, when vaporization starts, the pressure goes down and the candy will pop up because of that principle that I've already mentioned today, that the air, which is inside of the candy, will simply try to move out of the candy and it will like make some kind of pop up effect. The candy will open up and then we have the cooling, just to maintain the shape of the candy after we even the pressure in the chamber. But "sweet mode", as we call it also - has additional function and now we come to very important part of our today's lecture.

This is

This is because we want to have some tips, to share some tips on what to do if something happens. The major question is: what to do if after opening up the doors in your freeze dryer, it appears that the time for sublimation was not sufficient and product is still wet, that humidity level of your product is still too high? There are two ways here: the first would be to put this product into your freezer, for example, to defreeze the chamber and to start the process once again for example by adding at least 9 hours of sublimation. And this would be the classical way to go on.

But also another option would be that if your product is pretty dry, but not that dry as you would like to have it, so approximately 10% of humidity is left - then you can switch to "Sweet mode" and preset the preheating to lowest temperature, like 18° C, just to skip it and then to run the vaporization and you can do this vaporization for another, let's say, four or six hours - just to have an extra result with your product. Why is that? It's very important to understand, that when you open the doors in normal mode and your product, which was frozen inside, although it was plus 40° C on your shelves for instance, or plus 30 or plus 35 - depending on the temperature level you set, basically this ice will start to melt immediately inside of your product, and it's not possible to run sublimation, just to continue the sublimation without any problem. You need to change to vacuum drying then and you need to run vaporization to get rid of this water already, which is liquid inside of your product.

If you wish, of course, because it's possible sometimes to finalize the process so that if your freeze drying was too short, you can continue with vacuum drying just to get rid of residual moisture levels in your product. But if the product is too wet, it's better to keep it safely in some kind of a freezer and then to restart the process once again, giving at least 9 hours of sublimation, otherwise it will simply make no sense. You cannot call such product a freeze-dried product - this is the reason why you simply cannot continue the sublimation, when opening already the doors and seeing the product is wet. You cannot set the sublimation to less than 9 hours in our machines, because it simply makes no sense and we don't want to give you a false illusion that it's possible.

That's why we have a possibility to continue the process with vaporization in vacuum drying here, if you wish or you can simply restart the process once again, so that your batch is saved. I think this will be it concerning the operation of the machine from point of view of the menu. You've seen

Now, together with my colleague Nadia we will make a short test using samples of different products that we have here, on the level of humidity. Now actually we are using the Axis machine, that we also supply via our web shop, so you can find it there and we encourage you, actually, to buy such machine, because it's very useful in running activity based on freeze drying. Doing sample is very simple. The logic behind the process is such, that we need to monitor the weight of the product before when we put the sample on the weight, then we monitor the weight after the sample is heated to 100° (approximately) Celsius. 100° C or more: sometimes 105, 110 - it depends on the product and it takes approximately like, well, 30 seconds - something like that, to do the test.

I don't know which sample should we use, Nadia, here? Maybe strawberry? Yeah, let's do it then. Yeah, so if you, please...

Let's wait until the sample is now heated. We can see actually, how the process is going. Currently it's already approximately 1% of the heating. We'll come back just in a short while, when the sample is ready.

Now, when the device signaled, that it's ready, we can open... See, here is the sample, which is completely without any moist moisture left inside. And now we can see on the monitor, what is the result of such testing. Now I will tell you a little bit about the trays.

All our

Now we are opening the chamber with the oil pump and you probably wonder what is this small black box we can see here? This box is responsible for the unit operation, when there is a short electricity outage in your premises, when there was the freeze dryer currently operating. When we switch it on just like this, it will have enough power, it will provide enough power for the freeze dryer to run for another 5 to 7 minutes approximately to maintain the control of the unit. When the main power returns, it will simply allow to run the process further.

We have this in all our compact units, starting from LEO-004, ending with Leo-010L. It's a really nice feature to have, because you can be really sure, that everything will go well even if there is no power. Remember, please, that when you want to completely switch off the freeze dryer, you need also to switch off this switcher here. You probably are wondering how the construction of the freeze dryer looks like?

We will show

All our units as a standard have 50 mm of spacing between the shelves, so we can use both shallow tray like GN 1/1 standard here, it has 20 mm so I can put such tray here or we can use a deeper tray, which has 40 mm depths and of course it's very convenient to use such for example with liquids or with some products, that basically demand more space to be used, while freeze drying. Standard freeze dryers can utilize both. What you need to remember is that our LEO-whatever-L models, so this is basically all the compacts and LEO-030L model, - they have only 28 mm of spacing between the shelves and it's possible to use only shallow trays in such models. Because shelving system is fixed in smaller units we have, you cannot simply take the shelving away here.

This is because of the fluid, that is flowing inside of the shelves. We don't have electrical components in our chambers, this is 100% stainless steel, ready to be washed, for example, by pressurized washer. You need to make a decision about how big the spacing between the shelves in your unit should be, because this is not to be changed later. One more tip concerning using the trays: of course you can use the standard tray like this, because this is gastronomical norm, that's why it's called GN-tray.

It's stainless steel too and you can simply put your product inside of such a tray, but also to save you some time, for example, in terms of washing the tray later, you can use for example a baking paper. If you lay it evenly on such a tray, then you will save definitely much time afterwards when cleaning such trays, before the next batch. A very convenient way to go would be to have two set of trays: one will be working inside of the freeze dryer, while another you can use for preparing your next batch. And this is basically it, concerning the shelves.

It's very easy to use, very convenient to wash, you can use any type of detergent here, as stainless steel is not afraid of anything. So, basically you are free to go to clean it with whatever you like, however you like. While we are still here and talking about the trays, I would like to show you one more pretty useful thing. Sometimes

Sometimes people do the sweets and candies and we have developed special system here for the most popular candy type to be used, so that you can easily load these candies in such a way, that there is nice spacing between them, so they don't glue to each other after process is done. I will show you now this, how it's easily done. I will use some candies here and - let's let's see, if I have proper amount of these candies... Most probably it will be even too much, but never mind.

Basically, when I take this system now, afterwards what I should have is all the candies evenly placed around my tray. Yeah! It's a very convenient way to go with your candies :)