Now this is interesting. Why would the corks dry out? Wasn’t there a recent study that ‘proved’ that there was sufficient humidity within a bottle of wine to keep the cork in good condition, even if the bottle was stored vertically?
There was indeed a fairly recent statement by a top cork producer executive suggesting just that which included a reference to an AWRI [Australian Wine Research Institute] study that 'proved' it.
There is also a recent WinePages thread where this was discussed including reference to the above.
However the AWRI study did no such thing bearing in mind the relatively short time frame of the study nor was it even directed at the subject of corks drying out in low humidity environments.
In addition to which while cork-closed wines such as Madeira [generally] and Champagne [sometimes] have certainly be stored vertically the rational for so doing is different between those two wines with arguments between vertical v horizontal storage still current for Champagne - the main issue being the time over which vertical v horizontal performance has been measured in various humidity environments including studies by the CIVC.
As is generally accepted and while other issues are important, temperature [absolute and in variation] is
the key factor in storage requirements even short term whereas the humidity of the storage environment acts over a much longer term.
However what Tom says about cork quality is also relevant although the complaints 'Down Under' were not focused on corks drying out but on excessive levels of TCA [mainly] as well as, finally, the growing evidence of variable oxtrans performance causing unacceptable/variable levels of oxidation in shorter timeframes - something that was clearly visible as well as in taste in the white wines.
This resulted in the famous 'Screwcap Initiative' Down Under in the early noughties rekindling something that had been tried many years before and had been rejected, not because of poor performance but because of customer reaction. Nevertheless the 'Screwcap Initiative' succeeded and in addition to the vast majority of New Zealand and Australian wine producers now choosing the screwcap [there are a few significant hold-outs] it was also the major kick that got the dominant but shockingly complacent cork companies to invest heavily in cleaning up their act from harvesting through storage to new cleansing and production processes backed-up with state-of-the-art testing with Gas Chromatography-Mass Spectrometry [GCMS] equipment.
However corks
can dry-out in low humidity environments although storage temperature level and variation are a more likely cause of any dodgy wines - along with TCA too possibly particularly in the older wines.
