MagicalMedic

People often talk of 'caramelising' the sugars in agar or liquid cultures if you overdo them in the PC, and indeed if you do put them in too long the liquid or agar can go brown. It is often assumed or directly stated that this is bad and will destroy the agar / solution. I've also read however that dextrose / glucose is the main nutrient required by the mycelium in LC's - if this is true it seems odd that caramelisation would be a problem because the temperature for glucose to undergo pyrolysis (caramelisation) is 160 degrees C (as it is for sucrose and maltose) which cookers don't reach. For fructose(the most abundant sugar in most honey)the temperature is 110 degrees C, so it would caramelize in the cooker, but when sucrose undergoes pyrolysis it turns into fructose and glucose. I read this all on wikipedia [https://en.wikipedia.org/wiki/Caramelization#Effects_on_caramelization], and I'm an amateur, so I could be way off re. the nutrient thing. So what is actually degrading / decomposing when someone overcooks their agar and why is it bad?

I came across this offer from einseins regarding quality Culture lids and got me thinking about filters.. It seems there's heaps of options for filters on LC / spawn bottles, ranging from the pretty basic DIY like tyvek patches through to the purpose-made like the Whatman type used on these. I was wondering how superior such filters are? I'm guessing pore size is one of the main factors; the pore size for tyvek @ 2-15 microns {http://www.materialconcepts.com/products/tyvek/uv-soft/] is pretty big, but a lot of people seem to use this product for their filters. Plain medical masks you can buy at the chemist for next to nothing are considerably better - "tested to Bacterial Filtration Efficiency 99.9%* at 3 Microns". So obviously these Whatman ones are far superior, but are the other materials generally adequate - do people often experience contamination via poor filters? Was also wondering about the importance of airflow - even with a very efficient filter is there still plenty of oxygen or could mycelial growth slow due to C02 buildup?

Found these little fellas in woodchips after the rain in sydney- they look a bit like subs. They were dry when I found them so lacking a bit of detail, no spore prints either. Interested to know what species they might be & if they're common in the city? sorry about the image quality, had trouble uploading. At least the colours look true

Has anyone else had trouble with spawn drying out while the mycelium is still colonising the medium in jars? I've got WBS jars that were doing well but then I noticed black patches forming on the outside edge of the mycelium, followed by growth stopping. On removing the WBS (mostly colonised) it was very hard and crumbly and I realised that growth had probably stopped because it'd dried out so much. Is this a common problem if you've got large filters on the jars and you're incubating, and could you help it along by injecting more sterile water? This has happened in the past, the jars had been colonising for a few weeks. It also lead me to wonder how necessary filters are, if you can grow shitake in large sealed bags until the sawdust is fully colonised, for example, does myclium really need gas exchange to colonise - or is it different between species?

Thanks for the detailed replies! I am using a variety of jars - the smaller than 300ml ones colonised easily, those closer to or bigger than 400ml didn't colonise completely. The grain was soaked for one day and drained for a few hours. I am using material with very small pore size for filters (pore size is a tiny fraction of that of tyvek), and the filters are about 2x2cm - possibly unecessarily large. There is very little airflow in the incubator, it's a dual tub setup - but it has been warm, around 26 degrees. I haven't actually had any contamination this time around, I think the black spots were just dead or rotting material, as there was no evidence of it spreading or being fuzzy. I find it odd that there is still seemingly a fair bit of uncertainty as to whether filters are necessary or worth the risk.. Without filters your risk of contamination is so much lower, I'd only use them if I was certain they were necessary. Changing up the approack a bit sounds like a good option - soak the seed for longer and drain it better, innoc a bunch and leave some at room temp separate, and some without filters, to see if they colonise as fast. If colonisation times aren't too different, do away with filters. Edit: I hadn't considered the fact that palstic bags breath. Do you think it'd be enough to make a measurable / significant difference to say, colonisation rate in a truly sealed enviroment? The simplicity of directly innoculating bulk sub in sterile bags has always been appealing but I've not read much about it. I noticed in the mushroom growing course mentioned elsewhere in the forums recently, they used sawdust & straw bags sterilised and directly innocd for successful shitake. Would be much easier than the sometimes catastophic transfer of grain spawn to bulk sub.

Does anyone know of any particularly good online sources or descriptions to read about the specific geographic environments subs like in NSW? I've done quite a few fungus hunting hikes after rains over the year and many shroomies are in wild abundance.. I've got lots of photos of all the finds - but last year around sydney I didn't see any actives at all. I still find the idea of trying to hunt for actives really daunting - looking at many pictures and descriptions online leads me to think I could identify subs but I still feel like I'm very much in the dark as regards selecting potential areas to go and look.. I've noticed that details like the inclination of the land, the direction slopes face and the specific type of leaf cover can all apparently be critical as you see some species only flourish in quite specific conditons. Is trawling the forums for hunt accounts still the best way to get an idea of what kind of places to look? I find books are often europe/US-centric in their descriptions

A friend down the coast is trying to grow edibles from spores and made his own potato dextrose agar (boiled potato broth with some honey added) dishes. He inoculated agar dishes with one species weeks ago, and then tried another different species on dishes made from the same agar a week or so ago. No growth whatsoever has been observed on any of the dishes [with the exception of the germination of a single mold spore contam on one dish that grew well). Could it possible to make an agar with both potato starch and a little honey that just can't support mycelium? He additionally made a spore syringe from the remains of a dirty print, hoping to put this to agar to isolate clean mycelial sample at a later stage, but observed a few days later that little white fuzzy dots were visible in the syringe, despite the lack of nutrients in the water. Could this be germinated mushroom spores or is contam more likey? cheers

I just realised that of the maybe fifteen or twenty types of mushrooms I've tried my favourite is still the good old field mushroom (Agaricus campestris) - they're so rich and earthy, I love mushroom soup. I also only just learned that button mushrooms / portobello (Agaricus bisporus) you buy in the supermarket are a distinct species different from field mushrooms, I always thought they were just different cultivars from the same species. So what's the best you've grown and what are the best value for your time in terms of manageable difficulty for good mushrooms? edit changed lesser difficulty to manageable difficulty.. didn't want to sound like I'd be unprepared to go the distance for something a little special

Cheers for the info, yeah it's first time. Bizarrely after more than a month some of the spores from one variety germinated and are now growing mycelium (albeit slowly). A second attempt with a different variety yielded faster germination (about a week)and faster growth. The agar was all sterilised, only one or two obviously risky containers contaminated. I think a different agar mix is in order. Is it a problem sterilising the agar dishes / containers when they're already poured? This seems the best way to avoid contam, rather than pouring it out after you've sterilised - is the cooking time very quick in the case though to avoid caramelisation?

Low temperature I think - averaging about 22 degrees subject to daily fluctuations. I know this isn't ideal but he thought it'd just slow growth. Can it entirely prevent germination?

I thought this mix should work too. He took the recipe from a good source at the shroomery, almost certain it's not too rich. One slant I had a look at definitely had bacterial contam - slimy looking clear growth that clouded the agar, but the others all look fine. Inoculating some spawn with the syringe might be a good idea as I'm not sure how long germinated spores will last without nutrients (if they are germinated spores). I thought honey had D-glucose = dextrose?

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Rather than starting a new thread I thought here might be suitable to ask if anyone has tried pasteurising store-bought cow maunure? In the city it's easily procured at gardening shops and actually really cheap, but naturally it has been processed in some manner and might have nasty pathogens in it that you wouldn't find in poo straight from the field.

Had not considered that, I guess it's a trade-off between the various pros and cons associated with available options. Has this happened often or just once or twice, and were you sure contamination was due to the dirty port? Perhaps, assuming that you will only be puncturing the port a few times per grow, this problem could be solved by disposable ports - for the few times you use each port during individual grows you could make sure you puncture it roughly in a different spot each time, and when you feel the chances of contamination are rising you could inoculate a new LC in a bottle with a fresh port.

I've been perusing the backlogs and coming across heaps of threads and topics I want to save to find easily later, and I've been using the 'watch topic' function assuming I can use that to find my way back to those threads... but then when I go to my options - forums- manage watched topics to look at topics I've subscribed to there are only six there, none of the ones I've added lately are included. What am I doing wrong? Also what is liked content in the settings tab - how do you 'like' content? Final question which the above are basically aimed at; if I find threads I want to revisit later whats the best way to tag them / like them /add them to a list to make them easily accessible later? Cheers

There it is! Thanks man my bad, I totally overlooked that.. forgetting my chemistry

Just something I found out recently which some might find interesting; during the swine flu scare [i'm pretty sure it was] the Pharmacy Guild of Australia (PGA) took the precaution of sending out huge quantities of surgical masks to their member pharmacies to ensure widespread availability should the flu have gone pandemic. Some of the pharmacies now sell these masks very cheap, however those less stingy are often happy to give them to you free in packs of ten or twenty as they have hundreds spare and they don't sell. The great majority of Australian pharmacies are members of the PGA so you could try your local - just tell them you're working in a dusty environment and you need quite a few. Anywho these are potentially great filters - though tyvek has a pore size of 2-15 microns these masks are a double layered higher tech design rated to 99.9% effectiveness for bacteria at 3 microns - better than tyvek / polyfill and potentially free.

A 'save thread' / 'save topic' or 'favourite' function within the website would be awesome.. is this how the 'watch topic' button is supposed to work? [i.e. you can select 'no notifications' but there's still a list of all the threads you've 'watched' that you can easily access)? [atm this list is buried within the settings - it could be included on the drop-down menu] ..so much good material in the archives but no internal mechanism for quickly bookmarking & re-accessing them. If this was possible you could link people to old threads super quickly if they ask about stuff that's been well discussed in the past if you've been through the archives and saved the gold. Regarding using your internet browser's favourites function - I maintain a clean browser, devoid of browsing info/cookies/history/favourites etc, so not possible for me, but I think many would find this really useful if it were within the site anyway There's still the possibility it's just me experiencing problems / doing something stupid when trying to use the 'watch' function that's stopping the threads I add from actually being added to any visible list

Yeah man of course - you only need to transfer a tiny little sample of the mycelium to inoculate either. The trick is doing so without contamination.

Right well there's my answer at to why LC isn't so popular when it seemed appealing, thanks for such a comprehensive response. I guess all teks have their advantages/disadvantages for certain parts of the process, but that certainly puts LC in perspective.

Ah ok that totally makes sense. Thanks for the info man. Also I can get my mate to run that experiment, I'll update this then for interests sake; knowing breathers aren't necessary would simplify things a lot with in-jar humidity changes a non-issue and contam less likely.

Could easily experiment to see whether it makes a difference with / without a breather - ten identical capacity jars, five half filled with grain and with no breather, five near full with grain and with a breather, and all of them innoculated (ideally) with the same clone at the same time, then stored at the same temp as they develop. Then if the jars with roughly half as much grain were fully colonised in roughly half the time as the others you'd know it wasn't much of an issue, if they took any longer than half the time - breathers better. [also important to note if those with breathers contaminate more often though] TBH I assumed oxygen is pretty important. But if you've been colonising the grain adequately without any breather that's pretty solid evidence that it isn't in any way critical to have gas exchange - I guess it depends on colonisation speed and contam rates. Tripsis why is 'too much airflow' ?Also is airflow an unscientific term? it sounds a bit like it

Right yeah hadn't really thought about adding to much moisture. Using as a master sounds like it'd be a good idea though. Like OPP said too, not waiting for germination (once you've got an established LC) would speed things up heaps. I was thinking though; LC's are much easier to make and safely inoculate than agar plates - so if you were to make syringes and inject into say ten prepped LC bottles, some might be contaminated but it took like five minutes to make them right? so you can just throw the contaminated cultures if there are any. The main advantage though is there is no transfer from agar to LC / grain which seems like the riskiest part of the adventure, the part that'd likely require a flowhood. Is it harder to clearly observe mycelium growth in LC than it is on agar? The agar in the bottom of a jar then adding water after colonisation is great - no flow hood / glow box needed at any stage in the process, and you still get the benefit of watching growth on agar and excluding contaminates. That is smart. OPP I noticed you spell 'innoculate' with two n's as I was before the little red line starting irritating me.. is this correct australian / british spelling? All online dictionaries spell it with one n. As you said anyway so many options; up to the individual. one might easily avoid needing a flowhood/glovebox at all with the liquid process and all transfers using syringes though. Appealing in its simplicity and apparently minimal risk.

Right, thanks guys. I guess I can forget about the 'like' function if even torsten isn't sure about it generally not a fan of facebook integration anyway Yeah Ballzac it does take me to the page where you choose subscription type, it just seems that after that nothing is actually happening. Very odd.

Random question: does mycelium grow faster in grain spawn than it does it liquid culture? I've gathered from reading that the process of inoculating sterile liquid culture with a spore syringe, then drawing it off with a syringe via an injection port when ready and injecting this directly into substrate might be a relatively easy way to maintain sterility all the way through.. so why is grain spawn way more popular? If using a syringe & injection port with liquid culture you'd never even have to open the bottle