11 Freeze Drying Mistakes to Avoid for Best Storage Quality
Buzzing around Instagram and online freeze drying groups, I see a lot of photos of people showing off their home freeze dried goodies – and a lot of freeze drying mistakes.
We got our home freeze dryer earlier this year, and it's pretty easy to use, but there are some things you should avoid to get the best results for your food and your freeze dryer.
Some of these tips are for flavor, some shorten your drying time, some avoid messes and a few are real safety issues.
Freeze Drying Mistakes #1 – Mixing Raw Meat with Other Foods
Just like in the rest of the kitchen, you want to avoid cross contamination to prevent the spread of e coli and other bacteria.
Scientists use freeze drying to preserve bacteria samples. This means your odds of any bacteria on your raw meat surviving the freeze drying process are pretty high.
During the freeze drying process, water vapor moves around the freeze drying chamber. (The sublimation process takes the water in the food from frozen to vapor, skipping the liquid state.)
Please don't mix foods like fruits and vegetables that are intended to be eaten raw with raw meat.
If you wouldn't mix the foods on a kitchen cutting board, don't mix them in the freeze drying chamber.
Freeze Drying Mistakes #2 – Mixing Foods with Dissimilar Flavors
There are a number of sources that say you can mix and match even strong flavored foods in the vacuum chamber, as long as you put the strong flavored food (like onions) on the top shelves. I'm telling you otherwise.
Maybe those folks have wonky taste buds, but when we freeze dried green beans and bananas in the same batch of food, we ended up with green bean flavored bananas.
The flavor was subtle, but it was definitely there (and green bean bananas do taste as bad as they sound).
Since then, we've been careful to keep sweet and savory foods separate, with good results.
Freeze Drying Mistakes #3 – Attempting to Freeze Dry High Sugar Foods
Some foods like very high sugar content fruit, jams or jellies do not freeze dry well. No matter how long you leave them in, they will still be a little (or a lot) sticky. This is because sugar binds to free water molecules, preventing them from escaping the food. Normally, this trait is helpful for food preservation. Binding up free water slows down bacteria and mold growth, because those microorganisms need water to thrive. Unfortunately, it results in a less than ideal freeze dried product.
How much sugar is too much sugar? The good news is that most plain fruit still works very well, although sweeter fruits like peaches or pineapple will likely require a longer drying cycle.
The only fruit I've tried so far that took a very, very long time and still came out tacky was pears. There's a reason I refer to my dehydrated pears as “pear candy”.
I'll stick to dehydrating those, since the freeze dried pears came out very similar in texture to the dehydrated pears. Just skip the jams, jellies and other fruit spreads.
Freeze Drying Mistakes #4 – Trying to Dry High Fat Foods
One of the first freeze dryer reviews I read was from a fellow who attempted to freeze dry butter. He ended up with a massive mess. There was butter coating every surface on the interior of his freeze dryer, and it took a very long time and lots of work to clean up.
Of course, this got me wondering how much fat is too much fat, so I tried some pre-cooked, frozen breakfast patties. Never again – at least not unless I heat them up and remove as much fat as absolutely possible before freeze drying.
Like the first gentleman, I ended up with fat coating much of my freeze dryer. Even after a good scrubbing, it took weeks for the odor to fade completely. (Thankfully, other foods did not pick up the odor.)
The flavor of the finished product was a lot like sausage jerky, and they didn't rehydrate very well (see next mistake). Still, if you were hungry, I'm sure they'd be delicious.
Fat will also go rancid more quickly than other food items, so a meat or dairy product with higher fat levels is probably best used within 5 years. Make sure that if you want to freeze dry meat products that as much fat as possible is removed before drying. Full fat dairy such as whole milk, sour cream and cheese work just fine.
Freeze Drying Mistakes #5 – Freeze Drying Large Pieces of Meat
Perusing the freeze drying forums, I've seen quite a few accounts of people attempting to eat freeze dried pork chops – and having them taste like leather. Bigger hunks of meat simply don't rehydrate well. Even the sausage patties were mighty chewy.
For best results, stick to meat that is shredded, ground or diced. If it's normally served in a sauce, soup, or stew of some sort, even better.
Rehydrating with plenty of liquid and a lot of surface area for that liquid to soak into makes for a tastier meal.
The exception to this rule may be cooked shrimp, which some folks say rehydrates just fine for shrimp cocktails. (I have not tried this yet because we don't eat much shrimp.)
Small pieces of meat also make tempting snacks. (Our strips of fajita beef tasted like meat flavored cheese puff snacks AKA “meatos”.) Just make sure you don't eat too many dried pieces without drinking plenty of liquid so your internal plumbing doesn't get backed up.
Freeze Drying Mistakes #6 – Not Using a Liner in the Pans
The first time I loaded up my freeze dryer, I didn't bother with liners for the pans. After all, they're stainless steel, non-reactive and food grade. Not a good idea.
Like a kid with their tongue stuck on a metal flag pole, my freeze dried goodies did not want to come off the pan.
If you let them set around until the pans warm up, there's a risk that they will start absorbing moisture from the air and get soggy, ruining your freeze drying efforts. (Winter hasn't been bad, but in summer, when the humidity is sky high, this is a real issue.)
Invest in some sort of liners and save yourself a lot of headaches.
I purchased sheets of reusable parchment and cut them to size. You can also use regular parchment paper, too. With care, you should be able to use it for a couple of loads.
Wax paper and plastic wrap are a little too flimsy, and I wouldn't recommend aluminum foil because of the long exposure to aluminum for your food.
Freeze Drying Mistakes #7 – Expecting Quick Drying in Hot Weather
Just like your air conditioning, your freeze dryer has to to work harder the hotter it gets. Higher temps add hours to the drying time – sometimes many, many hours.
Our unit is in our attached garage, which is insulated but not air conditioned.
When the heat and humidity go up (80°+F), I take a break from freeze drying. If you live in an area where it's almost always hot and/or humid, I'd put the freeze dryer in an air conditioned space.
Also, don't operate the unit below freezing. You will very likely have water within the compressor (which is normal) but below zero it can freeze and destroy your compressor.
Freeze Drying Mistakes #8 – Freeze Drying Fruit with Tough Skins Whole
For fruits with tough skins like grapes, cranberries, cherry tomatoes and blueberries, extra minutes of prep time will save hours of freeze drying time.
Grapes are typically sliced in half lengthwise (like folks with smaller kids probably already prep them). We prep cherry tomatoes the same way.
For blueberries and cranberries, I freeze them on a baking sheet before freeze drying, and then give them a very brief spin in a food processor.
The goal is to nick the skins ever so slightly so water can escape, while leaving the fruit intact. I've also seen folks poke holes in individual berries, but the pre-freeze method is much faster.
Freeze Drying Mistakes #9 – Filling the Trays with Liquid Before Loading Them in the Unit
It's a simple thing, but may be easy to miss. Liquids spill. So – if you want to load up a tray of something like soup or milk, it's best to limit how far that liquid needs to travel in the tray.
Get your try in the freeze dryer, and then pour the liquid in – or load it right next to the freeze dryer and transport it inches instead of feet. Each tray will hold about a quart.
Freeze Drying Mistakes #10 – Filling the Freeze Dryer Too Full
The Harvest Right Freeze Dryer works by pulling water out fo the food and having that water freeze on the inside of the vacuum chamber, forming a layer of ice.
Too much food = too much ice = machine that can't finish the drying cycle.
I haven't run into this, but others who have say that they needed to empty the unit, place the food in a freezer, defrost the unit, and start the cycle again. Big hassle. Load the unit right the first time and save yourself some trouble.
Freeze dry no more than 10 pounds in at one time for the mid-sized unit – 6 pounds is a better limit for high moisture foods. (Check your specific unit for recommended maximum load size.)
Freeze Drying Mistakes #11 – Mixing Food Sizes and Stacking the Food Unevenly on the Trays
This is another problem that I see regularly – people mixing different shapes and sizes of foods, and stacking them unevenly on the trays. Big chunks will still be cold in the middle (and not completely dry) long after the small bits have finished.
A photo taken with a thermal imager will clearly show cold blue spots where the food isn't completely dry. Food stacked too deeply has a heck of a time dumping that water from ice to vapor. The top layers slow down or prevent sublimation from the lower layers.
Chop your food thin and/or small for the fastest drying time, and spread it evenly on the trays to prevent cold spots.
These Tips Apply for Dehydrating, Too
Most of these tips apply to dehydrating foods as well. Use common sense in the kitchen, and you'll get good results and safe and tasty food.
Do you have any questions about home freeze drying? Leave a comment and let me know. We've had our unit for a while now, and find it to be a useful addition to our home food storage options.
I am an affiliate for Harvest Right Home Freeze Dryers, so if you buy through my site I receive a commission at no extra cost to you. As always, all opinions are my own.
As far as I know, Harvest Right is the only company making home freeze dryers, but if you find out otherwise, let me know.
You can read more about our freeze dryer in the post, “Home Freeze Drying – The Good, The Bad and The Ugly“.
For tips on on how to optimize your freeze dryer use, check out “Harvest Right Freeze Dryer – Cost Analysis and Optimizing Load Size“.
For more food preservation options, check out:
- New to Food Preserving – Start Here
- How to Can Food at Home – 8 Steps for Safe Canning
- Getting Started with Home Food Drying
What happens to the food in the freeze dryer if I’m not available to remove it when the process is complete?
Will it soak up liquid?
Harvest Right says it can sit in there for hours without reabsorbing moisture. Maybe I am in a more humid climate, but when I let it sit, it does seem like it gets a little softer. If I can’t be home when it finishes (or it wants to finish in the middle of the night), I prefer to add extra time so that it finishes when I can empty it promptly.
When my unit finishes a cycle and I can’t take it out right away, it keeps the food frozen. Cycle ended some time last night and when I woke up and checked it this morning the unit said cycle complete and the temp was a cool -37.
Hi there, we’re in the process of ordering our machine.
Do you have better rates than offering directly from Harvest Rights?
Also, I appreciate everyone’s comments. I’m scared to commit as I can’t afford the waste.
Now the oil sprays and problems concern me.
The seal not sealing, and not freeze drying properly…. For the price to pay, is think they should run like Cadillacs lol, super smooth problem free?!
How is Harvest Right when it comes to customer service, issues, seals etc?
I’m in Canada and concerned of being stuck with not support after the purchase.
Please advise, thanks so much!!
Hi Tracy.
My referral links go to the Harvest Right site, so the price is the same. I am an affiliate for Harvest Right, meaning that I do earn a commission if someone uses my links, but the buyer does not pay extra.
The new pumps are way better than the pump I started with years ago, which was from a different company. Now, all the units are shipped with pumps designed exclusively for use with Harvest Right freeze dryers.
Alas, Cadillacs are not super smooth and problem free. Do a quick search on “Cadillac problems” and you’ll see what I mean. 🙂
The thing of it is, there are a lot of variables, and freeze drying is a fairly complicated progress, so there is a learning curve, and things can go wrong. The online forums are likely the fastest spots to get support. Odds are someone has run into similar issues, and most people in the forums are happy to help and there is almost always someone online.
The majority of customers have a good experience with Harvest Right, but no company can please everyone, especially in our society today where some people tend to fly off the handle. I do think they are a good company, but they have limited staff, so sometimes it takes a while for things to get resolved. They’ve been great to work with as a partner, and I’ve had no problem getting parts and new pumps over the years (our unit gets heavy use at times, and our unit is getting up in years). If they were jerks I would dump them. I have kicked other products off the site when they didn’t hold up with extended use, or added notes about issues.
HR is based in Salt Lake City, and the LDS community takes their food storage pretty seriously. If the company didn’t deliver, there’s no way they could stay in business in that environment.
I have 2 freeze dryers. A large and a medium. The large FD has been wonderful and quite a workhorse.
We have had issues with the medium size, but over all I would go with the medium size. It dries much faster and can process a decent amount of food. Ask Laurie for my email and I will be happy to detail our experiences along with how to resolve issues with the company.
Hi Laurie,
Regarding meat, is the freeze drying process itself better or faster if the meat is cooked first?
Thank you!!
I haven’t compared drying times for raw versus cooked meat, because I’ve only dried cooked. With cooked meat, you could eat it straight out of the package if needed, and a significant portion of the water has been driven off during the cooking process.
I know some people do freeze dry raw, and you should be able to find some discussion of it in online groups. It’s just not my thing.
If food is freeze dried and then placed in a mason jar with a lid, but without vacuum sealing or an oxygen absorber how long would it last? (for snacking or to eat within 2-3 days)
I have seen a few you tube videos with food store in this manner for “short term” storage, but I an unclear on what length of time that is?
The length of time varies depending on the food, the humidity levels in the house, and how frequently the jar is open.
Something fatty will not keep as long as a something without fat, for instance. If the house is very humid and someone leaves the jars open, the food will soak up moisture like a sponge and get softer within hours.
If we pack something in jars with no special treatment, we usually plan to use it within a few weeks.
Unfortunately I have already got a freeze dryer on order from a different site, so I can’t order from you! My question is, do I need oxygen absorbers in the freeze dried bags for longer preservation?
Also am disappointed to read that steaks and so on can’t be freeze dried!
Oxygen causes oxidation = spoilage, therefor if you remove as much oxygen as possible, you will increase shelf life.
You can also pack foods into vacuum sealed containers (like mason jars) that have the oxygen removed via vacuum sealing instead of via the absorbers.
Freeze drying gives you more options for food storage, but it does have limitations. You can’t stick a whole steak in a canning jar, either, but you may safely can beef chunks.
The newer 2021 freeze dryers will tell you when there’s been any interruption in power. I had started a pre-freeze on my small unit when the whole town’s power went out! Thankfully I didn’t have any food in it yet, but when the power returened, my freeze dryer said: Power outage – 1, duration, 26 minutes. and I was able to resume where it left off.
Yes, it was a short outage, thank goodness, but I didn’ t expect my freeze dryer to document it!
Good to know.
This is Barbara I think I might have a really big problem after I’ve read your site we’ve had our Freezedryer for about four years I’ve been freeze drying my food I always buy the The little packets they sell for the oxygen I put in every bag and every jar but I did not know about having to seal the jars I have about close to 2o 5 gallon buckets of packaged that I know is OK but I haven’t sealed any of those jars some of them have sealed their selves because I hear them but maybe some of them may not I have thousands of dollars worth of food in these jars I was saving if times get badBad or if my grandkids might need them for their family now I’m afraid to give any of the jars away am I going to lose them some of them are dated 2017 to right now I probably have 30 dozen eggs fresh and a few scrambled all kinds of stuff for my garden anytime I buy food and I keep my pantry for I go through and take anything that is getting low on date and I Freezedryer so I don’t have to keep giving it away like I used to so what do you suggest that I do can I just put another packet in there and put it in there and seal it will it still be good has it not been too long I was told his stuff could last 25 years but I guess that means with a good seal it looks good I would like to know if I buy a new motor for my Freezedryer nothing wrong with the one we have except my husband does not like changing it oil every time or to the new one you don’t have to can you get credit for it because that I’m already one of their customers thank you very much I really like your side I just found it last night
Hi Barbara.
If I am following you correctly, you’re saying that you have mason jars with food in them and oxygen absorbers, but the jars weren’t vacuum sealed?
Ideally, it’s best to vacuum seal jars with a vacuum sealer or your freeze dryer, but if the seal is air tight, the oxygen absorbers alone should remove the oxygen. If your jars are not sealed tight, then air (and oxygen) can keep sneaking in, and the food won’t keep as long. When you vacuum seal, and the seal holds, you know it’s tight and no additional air will get in.
Go through and test the seals on your jars. If they are tight, your food should be fine. If they are not tight, you want to use that food up sooner rather than later. A seal that isn’t tight means oxygen and moisture can still get in, which greatly reduces your shelf life.
When you talk about “buying a new motor”, I assume you mean replacing the original pump with an oil free pump?
To the best of my knowledge, Harvest Right does not offer a trade in program where you can get credit for turning in your old pump when you buy a new one. Shipping back and forth is quite expensive because of the weight, and most people keep their old pumps as a backup. From what I’ve seen in the forums, it looks like the standard pump may be a little more reliable than the oil free pump. But if your husband really dislikes changing the oil, you can call Harvest Right and double check. I know, like many industries, they are dealing with backorders and having difficulty getting materials for manufacturing, so their options are limited.
This is Barbara again the eggs I have dried or Duck Eggs goose eggs and chicken eggs I sure wouldn’t want to lose them would it hurt if I am sealed them and sealed them over or should I just leave them like they are one of the best things I’ve ever made in the Freezedryer I do not like spam my husband does I had a lot in the pantry and I was getting close on the date so I tried to dry it why did I get a lot of oil so I did it two or three times it was really good I don’t know what it looks like now if I was to open it and it’s in the bags but it was like eating a bacon run sudden let you know about that I was kind of neat I’m up there pretty good years so I hate losing all my work I hope it works out for me and appreciate your help and I will probably be doing more with your Site later thank you for your answer backI’m not very good with a computer but I’m learning I would like to join but I will have to find out how to do it I’ll have my daughter help me thank you
Check the seal on lids. If they are tight, don’t open them.
Use fatty foods (like spam) sooner rather than later. Even with oxygen absorbers, the fat won’t keep as long as no-fat foods, like fruit and veggies. I’d try to eat them within 5 years of freeze drying.
I just finished a batch of raw chicken. I should probably sanitize my rack and chamber before doing raw fruit next, right? Any good suggestions for this besides soap and warm water on a soft cloth?
Thanks!
I treat freezer dryer cleaning like kitchen cleaning, which means that I think warm, soapy water and time to dry after cleaning should do the trick. (Bacteria like moisture.) I don’t know how the surfaces of the freeze dryer would hold up to harsher cleaners, and I normally don’t use them in my kitchen.
I am new to all of this… just getting ready to order my Harvest equipment. You have mentioned vacuum sealing your mason jars, and you will probably think I am dumb to ask this question. How do I vacuum seal a mason jar without boiling it?
If you’ve never done it, how would you know?
I usually use the jar sealer attachment for my Foodsaver vacuum sealer, but you can also vacuum seal directly in your freeze dryer. The video below shows how.
See https://commonsensehome.com/vacuum-sealers/ for more information on vacuum sealers.
I have a question that I can’t seem to find an answer to. What happens if you add more dry time when it wasn’t really needed? Or can’t get back tot he items for a few hours. Can you “over-dry” food? We did ice cream sandwiches and they seemed to puff up twice the size, I have never seen that happen on the videos, they looked the exact same, so I wondered if I was not supposed to add more dry time??
Adding more dry time is fine. You cannot “over dry”. It do it all the time when loads look like will finish at oddball times.
Ice cream varies widely depending on what brand you use. It’s definitely a good idea to pre-chill the freeze dryer before loading it in. Ours puffed up quite a bit, too.
What about the possibility of botulism forming in certain vacuum sealed freeze dried foods? I have been advised by home economists that soaking and then freeze drying raw nuts as well as vacuum sealing home freeze dried cheeses and some vegetables could permit botulism to form.
If your food is properly freeze dried (97-99% of water gone), it would be impossible for botulism spores to grow.
Botulism spores require:
Temperatures between 40-120°F/ 5-49°C
Anaerobic conditions (Oxygen below 2%)
Neutral pH
Moist conditions (Water activity level greater than 0.85)
If you were simply vacuum sealing cheese or other foods without drying, and storage them at room temperature, then the conditions could be met, but if the foods are properly dried, the spores won’t grow.
I’m new to freeze drying and have already learned so much from your site!!! Thanks for sharing all your knowledge!!! I know mylar bags are best for storage, but i have some mylar bags with a clear front… do you have any idea how long foods will last in these types of bag? I want to use them since i have them, but i also don’t want to take any risks storing them too long. Any information would be helpful. Thanks! 🙂
I can’t find any suggested shelf life for the clear front Mylar bags, only that they are not recommended for long term storage. I would think they should be fine for one to two year storage, similar to plastic vacuum seal bags.
I’m new to freeze drying and have done strawberries and apples but in comparing them to what I get from Trader Joe’s, my version looks nicer but they aren’t as “crispy”. I’ve tried final dry time up to about 30 hours but the result is no different from about a 12 hour final dry. I assume they are completely dry but the barely have a crisp to them. They have a much softer feel when you bite into them compared to the Trader Joe’s ones. I wonder if Trader Joe’s starts with frozen product? I noticed theirs looks like they have shriveled a bit while mine looks just like fresh? I prefer that slight crunch and was wondering how I might achieve this? Another question I had was would there be cases where it would be better to use gel silica packs instead of oxygen absorbers when storing product? Thank you in advance.
Are you taking them out of the freeze dryer as soon as the cycle finishes, or getting to them a while after the cycle is done? I’ve found that if I let them sit in the freeze dryer, they get soft and less crisp. (Harvest Right says you can let finished food sit in the freeze dryer. I disagree.)
If you have been taking the food out as soon as it finishes and it’s still soft, even with the long dry time, something might be off in your moisture sensor calibration. Mine come out crisp when they are properly dried, and I start with fresh berries. You’d need to talk to HR about that.
If I suspect the food might not be quite as dry as it should be, I include a desiccant pack and an O2 absorber in the storage container. Unless it’s short term storage, I always use an oxygen absorber.
Freeze dried pork chops. We just finished a batch, they turned out wonderful. re-hydrated one to check it out, seems just like they were before we freeze dried them.
Starting with 14 lbs. raw chops, about 3/4 inch thick. First we took off all the fat and bones, not just some, but all the fat that could be trimmed. Approximately 1/3 on the volume came off in bones and fat.
Next we fully cooked them with marinade and seasonings. then froze them in the deep freezer before they entered the freeze dryer. this only made 2-1/2 trays. the other 1-1/2 trays were filled with cooked chicken thighs. de-boned and fat and skin removed. once again, about 50% was removed. They dried extremely fast, one of the fastest items I have ever dried. About 18 hours. very little signs of oil left in the trays.
After re-hydrating, heating and tasting, this was very very good.
Thanks for sharing your experience.
I really want a freeze dryer but I’m afraid of not getting the result I want. I will only be using it to freeze dry raw meat for my dogs. I need to be able to freeze dry raw meat patties then be able to put them in a reclosable plastic bag and take them with me on trips. The meat will need to remain in a solid state without being vacuum sealed. When I feed the dogs I will need to be able to break up the patty and add water to it to make it moist. I will also freeze dry raw meat treats for them like sliced turkey hearts. I bought a package of freeze dried turkey hearts last July and they are still good without being stored in a vacuum sealed bag. That’s what I want but I’m not sure that this freeze dryer will give me that. Can you advise me?
The quality of home freeze dried products should be as good or better than commercial products. Ideally, I’d still recommend vacuum sealing in a jar (or using Mylar) for the products that you are not using immediately. You can do this with your freeze dryer if you don’t have a separate vacuum sealer. The fattier the meat, the less shelf stable it will be. Extremely lean meat will last longer, even without vacuum sealing.
When you say the hearts “are still good”, I assume you mean they look the same and aren’t showing obvious spoilage. Even with commercial products, it’s best to use them within a month or two of opening a container for best quality. At nearly a year old, freeze dried or not, those hearts are no longer at best quality.
I realize you can’t taste the meat (without cooking it) since it’s raw, but you might want to try giving it a close smell or having other people smell it. After months exposed to oxygen, I would expect it to be slightly rancid, even with freeze drying.
There shouldn’t be an issue with not vacuum sealing freeze dried meats that will be used within a month.
Not sure – I did not open it, but it is pretty cold in our house (below 64)… The dryer did not warn me of any potential danger, but gave the message “Restarted after power outage”. The dried food looks fine, for whatever that is worth :). We were gone about 6 hours, but not sure when error occurred. I think it resumed at 5+ more hours of freezing to go. Thank you again.
If you’re curious, the first part of the video below demonstrates how to download the data log from your unit, which you could access in Excel to check the down time and temps.
I have the medium freeze dryer and when our power went out it told me on the screen when I got home that the power had been out twice for a total of one. Five hours and then it resumed automatically when the power came on.
Hi! I am enjoying all the knowledge posted here! I just got my Harvest Right, and at some point during my freeze cycle there was a power outage (after at least the first 3 hours – maybe 4). I got it to resume, but am wondering if the food inside (mashed potatoes and cooked chicken strips) will be safe, or if spoilage may have occurred. We were away from home so I am not certain just when or how long the power was out. Any thoughts on this? Thank you.
That’s a tough call. Could you tell if the chamber was still frozen when you started it back up? That initial freeze cycle gets really cold, so that would buy you several hours of safety. If you think it thawed and sat, I’d be a little concerned.
We did our first batch of onions a few months ago and cannot get rid of the smell. We did ice cream and apples afterwards (made days or weeks later) and they taste like onions!
How do you get rid of this smell/contamination!?
Personally, I’ve avoided freeze drying exceptionally smelly foods like onions. Given that the deed is done, that’s not an option in this situation.
The problem is that the oils that cause the off flavor are now coating the entire vacuum chamber of your freeze dryer, and likely the drain hose, too. If you haven’t done it already, I’d suggest carefully removing the rack and washing down all the surfaces with warm, soapy water to remove the oils.
If that doesn’t clear the odor, you may want to try something specifically designed for odor removal, like the options mentioned in this post – https://commonsensehome.com/best-odor-eliminators/.
Thank you for your excellent comments. I am the one who sold my small for a large size freeze dryer… but… it has been down for several weeks. Every cycle I did was 46 hours long (no matter what I put into it), and some of my food wasn’t dried. Your suggestions are excellent, but I think I have a problem with the seal. There is a tear in the foam insulation and the unit creates puddles on the floor from condensation (it is in a conditioned basement space, the same space I had my small unit it, never had any humidity problems). Anyway, I have been waiting on some replacement parts from Harvest Right, but so far they haven’t arrived (about 2 weeks). Guess I should have kept the smaller unit… darn!
Something that Harvest Right said is although they sell the silicone tray liners, that the parchment works better for anything with a higher moisture content. I hate that, because the tray liners are so easy to clean and handy.
So sorry you’re having issues with the larger unit.
Before Harvest Right started selling their silicon tray liners, I ordered some reusable parchment sheets from Amazon and cut them to size. I use them for everything and they clean easily. They’re a little easier to crumple than silicon sheets, but if handled with reasonable care they hold up fine.
I found regular parchment paper to be a bit of a hassle.
*ahem *hint hint Harvest Right has an opportunity being presented to them to please their customers and still potentially make money. They can be the first to create the multi use parchment paper. Presented as a paper towel roll, perforated at the proper lengths to fit trays. This option also addresses the oversized parchment paper available to us in the stores as being to cumbersome to use or store so we opt out altogether.
Thank you for listening,
Harvest Right does sell silicon mats that fit in the trays as liners. They were introduced after I got my unit and made my own. 🙂
I need to make time to update posts. Not enough hours in the day.