Cheese like aroma , taste in cider, anyone had similar experiance?

[William Grote]

This year was the first that I harvested a variety of local crab apples from both urban and rural trees, and added them in various amounts to at least 6 batches of dessert apple cider.

half of the crab apple batches has a very distinct 'cheese like' aroma and flavor, in varying degrees, not a ripe soft rind cheese, more like a hard cheese, but none the less, not what I expected.  The flavor is not bad, it is just, well, slightly cheesey?

At first, the only thing I can attribute this to is the batches that got dosed with various crab mixes & had some seriously wild funk going, but in looking at my notes, the cheesiest of the batches was crab free, sulfited at 50 PPM initially,  and topped off with nothing but pasteurized local cider.   I had noted a distinct sulfur smell during primary and had been fermenting at 45F, so I moved it up to about 50 where it has been ever since.  This is also the only batch of the season that is not clear yet after 2 rackings (compared to same juice, same treatment brethren with different yeasts )

I pitched VR21 in this batch after having superb results with it last year, but got none of the desired characteristics.

So now I have a cider that could be "Apple Pie with Cheddar " 

I could find zero reference to cheese like off flavors everywhere I looked, so I was hoping to find some insight here

[Mike Reis]

It sounds like you may be having an issue with isovaleric acid, which is produced by Brettanomyces. I believe Brett can continue to break it down into more pleasant esters, but I'll let the cidermakers weigh in on solutions for you! Good luck.
M

[Andrew Lea]

On 19/04/2016 07:21, Mike Reis wrote:
> It sounds like you may be having an issue with isovaleric acid,
>

> On Saturday, January 30, 2016 at 10:26:25 AM UTC-8, William Grote wrote:

> half of the crab apple batches has a very distinct 'cheese like'
> aroma and flavor,

I missed this thread the first time around but it ties in nicely with
William's other aroma thread running right now.

If you look at Table VII in the paper I previously cited
http://onlinelibrary.wiley.com/doi/10.1002/j.2050-0416.1974.tb06795.x/epdf
you will see a list of volatile fatty acids from cider and their
flavour descriptors. In particular the cheesy notes are often associated
with butyric acid and with 2- and 3-methyl butyric acid. The latter pair
are also known colloquially as 'iso-valeric acids' as Mike says.

I would not expect them to hang around over their sensory threshold
during cider maturation, unless some microbial infection remains
dominant. Rather, I would expect them to esterify over time to give
ethyl butyrate and ethyl 2- and 3-methyl butyrate, whose characteristics
are listed in Table VI.

William, have these cheesy notes gone now? Have they matured away by
natural esterification?

Andrew

--
near Oxford, UK
Wittenham Hill Cider Portal
www.cider.org.uk

[William Grote]

Morning Andrew, as always, thanks for responding!

I am happy to say that on one batch the 'cheesy' esters have completely gone and the cider has no taste associated with the former esters.  The other batch retained some, though there might have been, as mike suggests, some Brett involved as I mixed in some crabs to that one. 

The former cheese batch, which originally was a simply fantastic blend of juice made from heritage apples from Pine Hill Farm in MA, has a very very slight Aceto aroma now when left in the glass for a few minutes, but not even the slightest taste of vinegar.

Is the smell threshold for vinegar lower than the taste threshold?  Or are there any other compounds that smell similar to those resulting from acetobacter infection, but are not aceto?

[Andrew Lea]

On 22/04/2016 14:16, William Grote wrote:

>
> Is the smell threshold for vinegar lower than the taste threshold? Or
> are there any other compounds that smell similar to those resulting from
> acetobacter infection, but are not aceto?

There is no chemical called 'vinegar'. It is a common myth that acetic
acid smells vinegary (simple because acetic acid is the major component
of vinegar), but the pure solution hardly does. The characteristic aroma
of vinegar itself is mostly due to ethyl acetate and other related
esters with an acetic acid underlay. These esters are odour active at
much lower levels than acetic acid, hence the vinegar aroma (which
differs from type to type). But when you taste vinegar of course you
also taste the sourness of the acetic acid plus you have the aroma of
the acid and the esters via the retronasal route, and together they
contribute to the overall vinegar flavour.

It is quite possible to get ethyl acetate / acetic acid in ciders from
sources other than acetobacter; for instance from lactobacilli and
apiculate yeasts. That is why 'vinegary' is such a widespread flavour
descriptor / fault in ciders, even where no acetobacter and only a touch
of acetic acid is involved.

[William Grote]

Andrew

you convinced me at retronasal (olfaction) :-)

So good to know that there are reactions other than acetobacter that can create ethyl acetate, but If I smell it, yet taste nothing approaching vinegar, can I relax or should I worry that this batch might have been infected and is worsen with any exposure to O2?  

Which comes first, the esters or the egg? ( Easter eggs in America are often dyed in vinegar spiked color solution )

William

[Andrew Lea]

On 26/04/2016 14:16, William Grote wrote:

> So good to know that there are reactions other than acetobacter that can
> create ethyl acetate, but If I smell it, yet taste nothing approaching
> vinegar, can I relax or should I worry that this batch might have been
> infected and is worsen with any exposure to O2?

I always regard ethyl acetate / acetic notes in cider, at the stage
where they are detectable but not yet fully unpleasant, as something of
an early warning, something that prompts the question - "is my process
fully under control?". Because it can come from so many different
sources the answer may be different at different times and for different
people.

Ethyl acetate /acetic doesn't only occur by oxidation - in UK perries it
comes from lactic acid bacterial breakdown of native citric acid and in
Spanish ciders probably by LAB action on juice sugars during
fermentation. In UK farmhouse ciders it more likely comes from oxidative
processes eg apiculate yeasts or acetobacter.

The reason it's so widespread is that ethanol is the major alcohol
produced during fermentation and that acetic acid is also generated by
many related biochemical processes. They are not chemically exotic
beasts but simple molecules, the end products of much microbial
metabolism, and so it's not surprising that their simple ester is
widespread too.

Whether it's a problem or not depends on your culture, as well as how
bad it gets. Many of the European cider cultures (eg Spain and the UK
West Country) seem to welcome some acetic character, probably because
that's traditionally how they've always been. Up to the re-introduction
of SO2 here in the 1960's it was probably endemic in all UK farmhouse
ciders and in many it still is. I would guess the modern New World cider
cultures have zero tolerance because they are starting from a late 20th
century perspective where it is seen to have no place. I'd guess that
the ciders of Johnny Appleseed's time were pretty acetic though ;-)

For myself I can be in a position where I recognise it without finding
it offensive, but I might mark it down as a fault even so. I was at a
small West Country competition last year where I was marking some ciders
down for their acetic character but my fellow judge was marking them up
for precisely the same reason! He was a born and bred West Countryman
while I am not. In cider, your background culture can often be critical
to what you enjoy or what you don't.

The good news, if you want a one-stop solution to prevent ciders going
acetic, is that SO2 is your best friend, because it is both an
antioxidant and an antimicrobial which pretty much zaps the offending
microbes whether they are oxidative or not.

[William Grote]

Andrew

Thanks again for taking the time to give such a thorough response.  

The subjective influence of culture and tradition in food preferences never ceases to amaze me, most asian cultures are as horrified by our love of fermented milk as we are of their love for fermented soy.  One man's poison....

In any case, this was a very helpful answer!

Thanks

William