Mead - Final Product One Year Later

Way back in October 2016, I was frustrated with stuck fermentation on a batch of mead. Adding yeast nutrient/energizer, fermentation seemed to do the trick. Three months later, in January, I measured the specific gravity (0.996) and decided to rack it. Some residual haziness remained, so I let this mead sit for 7 months in the dark, in a sealed carboy, hoping that this little bit of cloudiness would settle out. Last week, I decided to rack again, and maybe bottle it.

During the racking, I took pains to avoid bumping the walls of the carboy with the auto-siphon, as fine particles had settled there. I also left avoided siphoning off the bottom inch (or so) of liquid, thus avoiding most of the fine sediment. The racked mead seemed to not have any visible particulates, although there was still a fine haze. I decided that it probably wasn't going to get much better by letting it sit for another half a year, so I went ahead and bottled. And, frankly, the minor haziness is something I can live with.

Minor haziness is most visible in full sunlight.

The final specific gravity was 0.994, slightly lower (but within experimental error) than the s.g. in January. Total yield was 14 bottles, plus another 300 mL or so that I put in the fridge for immediate consumption.

So, is it any good? Well, yes. This mead is far better than the my first attempt, which was made using some generic honey from Costco. This one has more interesting, complex honey flavours, and it tastes 'clean'. It is also very dry and it's delicious when chilled - a perfect summer treat.

Peach Melomel - Tasting & Bottling

Three months have passed since I racked the peach melomel to let it clarify. Passive clarification was effective in this case. The melomel was crystal clear at the time of bottling.

I siphoned the melomel into a sterilized carboy, and stirred it vigorously for about ten minutes. This was to remove residual carbon dioxide. I actually did a taste test before and after stirring, and it was easy to detect the reduction in carbonation. I also took a specific gravity reading, and found it unchanged from the previous measurement.

Bottling was a snap. The three gallon batch is a good size for my purposes. This yielded 14 (and half) bottles in the end. Some volume is always lost in the racking, but that's fine.

Bottles of peach melomel.

I like the taste of this batch. The taste is light and reminiscent to some dry white wines. It has a mild honey aroma, and the honey taste seems most noticeable at the front and middle. Then, a gentle fruit flavour emerges at the end. The acidity is just right. But the odd thing is that I have a hard time identifying a peach flavour!

Fruit flavours come from organic compounds called esters, and the pure compounds have very specific tastes and aromas. One of the fun things about esters is that they are easily transformed into other esters, under certain chemical conditions. That means you can transform an ester with one particular flavour into another ester that has a totally different flavour. All you have to do is mix up the ester with a little acid and an alcohol compound (the alcohol that we drink is an alcohol known as ethanol).

So, here's one hypothesis: peach flavour comes from "linalyl" esters. In the presence of ethanol and acid, these could be converted to the corresponding "ethyl" esters. The ethyl esters in question are present in bananas, lemons, pineapples, and strawberries. When I sip this peach melomel, I taste hints of all of these. (Caveat: this is just a hypothesis.)

Another, perhaps more likely, scenario is that the peach linalyl esters decomposed into carboxylic acids, which do not have fruit flavours at all. :(

"Peach" Melomel. More like "Fruit" Melomel.

 

Fermentation Kinetics

Since I "re-started" the fermentation in the mead about three weeks ago, I have kept an eye on the fermentation rate. It seems to be going as one would expect: after the large increase in bubble rate over the first 2-3 days, the bubble rate has been decreasing slowly. As a chemist, in this sort of situation, I can't keep myself from taking measurements and recording them in a table. For many years, in all sorts of chemistry experiments, I measured and modeled chemical kinetics (i.e. the study of the rate of reactions). Here's what I found about the mead fermentation.

Method: Measure the number of airlock bubbles per minute, noting the time and date. Calculate the logarithm of bubble rate, and make a plot of this against time.

This is what is known as a "first order plot". It shows that the rate does not decrease linearly, but that the rate of decrease slows down with time. This is typical of reactions in which the rate depends on how much of the starting material, or reactant, is present. In the case of fermentation, the reactant is sugar. As sugar is consumed by the yeast, the rate of fermentation will obviously decrease. However, the decrease in rate is not linear - the "deceleration" slows down over time. In this type of reaction, when you make a graph of the logarithm of the rate vs. time, you get a straight line. That's what happened here.

Fermentation kinetics are actually a lot more complicated, especially at the beginning of the fermentation process, when yeast populations are growing, and the fermentation rate is accelerating. In this case, fermentation is almost complete and the yeast population is no longer growing. There are lots of yeast cells present, and the rate is only limited by the amount of sugar remaining. The result is "first order kinetics".

One day, I would like to try measuring the fermentation rate from start to finish, but it gets complicated. Measuring airlock bubble rate would be a pain during primary fermentation, when the rate is quite high. The other way you can measure the rate is by looking at alcohol content. The problem with alcohol content is that the measurement is in situ, requiring the insertion of a wine thief and hydrometer into the must. This increases the likelihood of introducing oxygen or microbes into the must.

  

Stuck Fermentation

What is it about mead and stuck fermentation? If you google search "mead stuck fermentation", you find that this is a widespread problem for home mead makers. I recently had to deal with it in my most recent attempt at mead.

Back in August, secondary fermentation of this mead had more or less stopped. Things had been going pretty well, and I assumed that most of the sugar must have been used up by the yeast. As I noted in an earlier post, I broke my hydrometer and therefore had no quick way to measure the specific gravity. (Actually, I could have measured out a volume of mead and measured the mass, from which you can easily calculate density. I have a cute little jeweller's electronic balance that measures to 0.01 g.) So, without knowing the completeness of the fermentation, I racked the mead with the intention to let it age and clarify.

As the mead was "aging", I noticed that there was a constant, very slow rate of gas production in the carboy. In the meantime, the batch of peach melomel was getting to the end stage of secondary fermentation, and it was time to rack it. Last week, I decided to rack the melomel and the mead, checking the specific gravity of each using my new hydrometer. Here's what I found:

Peach Melomel s.g. = 0.990 (Conclusion: fermentation is complete, and it's time to let it age)

Mead s.g. = 1.038 (Conclusion: oh crap, fermentation is stuck)

So, I had to intervene. I added two Campden tablets (crushed and pre-dissolved), 1 tsp of yeast nutrient, and a packet of Lalvin EC-1118 yeast. Bubble formation seemed to pick up within a few hours. The next day, gas production still wasn't as fast I would like, so I raised the temperature in the room using an oil heater, and also added 2 tsp of yeast energizer. Yeast energizer has a slightly different nutrient mix as yeast nutrient. Three days later, the fermentation in the mead was chugging along nicely, and continues:

Gas production after kick-starting the fermentation

with yeast nutrients and higher temperature.

Did fermentation resume because of added nutrients for the yeast, the higher room temperature (from 17 up to 22 degrees C), or both? I don't really know, but I suspect it was mostly the nutrients. After all, the peach melomel, which presumably had more nutrients from the peach juice, seemed to work out fine in the relatively cool room in which I keep this stuff. Lesson for next time: add more nutrient, with the proviso that "yeast energizer" is likely the more effective.

Peach Melomel

For a couple of years, I have followed home winemaking posts about small batches of melomels. A melomel is simply a mead amended with some kind of fruit. You can use any kind of fruit you want. The resulting mead will have a mix of honey and fruit flavours.

I had some good honey leftover from the most recent batch of mead, and we had some fresh fruit from British Columbia, including some very juicy, perhaps even overripe, peaches. This presented an opportunity to try making a peach melomel, which struck me as a potentially nice combination.

Here's the recipe I used:

- 10 L of filtered water
- 3 campden tablets
- 2 tsp yeast nutrient
- 1 tsp peptic enzyme
- approximately 3 kg honey
- 1 cup of sugar*
- 11 pitted peaches, sliced
- packet of Lalvin EC1118 yeast

*Sugar was needed because the dissolved honey only gave s.g. = 1.078. The sugar brought up the s.g. to 1.086.

After mixing up all the ingredients except fruit and yeast in my primary fermentation bucket, I put the peaches in a nylon straining bag, tied it off, and squeezed the peach juices into the must. The amount of peach juice was surprising. I put the whole bag of strained peaches into the must and let it sit for 36 hours. After removing the bag, I sprinkled yeast on the surface. A few hours later, fermentation was going strong.

Fermentation "head" on the peach melomel

After six days of primary fermentation, the 'head' had collapsed, and s.g. = 1.024. I transferred to a sterilized 3 gallon carboy for secondary fermentation.

Peach Melomel in Secondary.

Unfortunately, these pics don't really show the subtle peachy colour of this melomel. I'm looking forward to seeing how the colour turns out after it's aged, clarified, and bottled.

Beeswax?

Back to the mead...

Four weeks ago, I racked the mead into a carboy, to allow secondary fermentation to proceed, which it did. Fermentation was more or less over a couple of weeks ago Tonight, I decided it was time to rack the mead into a clean carboy so the mead can bulk-age, lose CO₂, and clear up.

During secondary fermentation, there was a small froth on the surface, which isn't a big deal. However, as fermentation slowed down, a fine, beige solid remained on the surface of the mead, and along the inside, top surface of the glass, under the neck. The solid never dissolved.

Beeswax?

After racking, I managed to swipe my finger into the dirty, empty carbon, and get some of this material. It was granular, hard, but seemed a bit 'gummy', like paraffin wax. Question for honey and mead people: Is this beeswax?

This particular honey is not heavily processed. I used 2-3 kg of honey, so it wouldn't be a surprise if there was a small amount of beeswax in there.

Sadly, before I could measure specific gravity, I dropped my hydrometer on the floor. So, I cannot estimate alcohol content of the mead right now.

The mead sure tasted good, though. I was surprised by the sweetness. Fermentation was OVER. There shouldn't be any residual sugar in there. It could be that there are other sugars (e.g. pentoses or something like that) that the yeast did not touch. This deserves some research. Question for honey people: what types of sugar are present in honey? 

Mead v.2

My first attempt at mead left me unsatisfied. Looking back, there were three things that I did incorrectly:

1. Failed to add yeast nutrient. Honey does not have the range of minerals and other nutrients that yeast require. Fermentation only really started once I added the yeast nutrient. Further, all of my  fussing around to get fermentation started would have introduced unwanted oxygen, which would have led to undesirable compounds that affect taste.
2. Starting specific gravity was too high at the beginning (1.120) and the end (1.019) of fermentation.This gave a mead that was sweet, heavy, and very alcoholic. The balance of taste wasn't right (and still isn't!).
3. Honey quality. A friend from my undergraduate days at university now runs a honey business, and she pointed out that Costco honey is rubbish - if I want to make good mead, I need to start with quality honey. ("Okay. Point taken.")

So, it is now over two years after my first attempt at mead, and I finally got around to my second attempt. This time, I'm not making any of the mistakes I made the first time.

We have a great farmers market in St. Albert, and there are always three or four honey producers there. My wife and I went shopping one Saturday morning and obtained 7 kg of unpasteurized, local honey for $50. The vendor was Good Morning Honey Ltd.

Mead recipe:

3 Campden tablets
2 tsp yeast nutrient
10 L distilled water
Honey
1 packet of Lalvin EC-1118 yeast

Campden tablets and yeast nutrient were added to the water in the sterilized primary (bucket). Honey was added, with stirring, until s.g. = 1.088. After 24 hours, the yeast was hydrated and added to the must. Fermentation bubbles were observed within one hour of pitching the yeast.

After four days in the primary, s.g. = 1.065. I decided to rack the mead to a carboy. Fermentation has continued since then (6 days ago).

Mead, after racking to carboy.

I think most chemists will know what I'm talking about when I describe this fermentation as "clean". What I mean is this: when chemists conduct a chemical reaction the lab, especially when they are trying to synthesize a compound, they strive for a "clean" reaction. A clean reaction is something we recognize easily from the absence of unwanted precipitates, the absence of guck on the sides of reaction flasks, the relative transparency of solutions, and colours that you want to see (e.g. you don't want to see your mixture turn brown when the product you want is colourless). These are simply physical clues that a reaction is going right.

This mead has been "clean" from the beginning: the colour hasn't changed, the liquid is as transparent as you could expect if there were only little bits of yeast and bubbles that were scattering light. You can tell that clarification is going to be a snap. And, there was hardly any foaming, which suggests a very pure honey (i.e. no surfactants of any kind - natural or artificial).

The plan is to let this mead ferment all the way to dryness and then I will rack it and let it bulk age in a carboy for a couple of months. I'm looking forward to enjoying some of this mead over the Christmas holidays.

Homemade Labels

However much I like the peel and stick labels you can get for wine kits, it's much more fun to make your own.  I like to employ children to help with this.  They love it.

First, ask the young person to draw something related to the type of beverage.  When they finish, scan the image and then make up your label in Powerpoint by inserting the image and adding text.  Resize the label and print!

To stick the label on the bottle, I simply use glue stick.  It keeps the label on just fine.  When you are finished with the bottle's contents, it's very easy to wash the label off because glue stick is more or less water soluble.

It's that easy.  Take a look at the mead that was bottled a few days ago.  The label adds a sort of professional touch.  (Also, notice how clear the liquid looks.  The fine solids have settled out!)

Sunnyside Mead 2014

Bottling the Mead

Mead v.1 was ready for bottling about a week ago, but I could not find time to bottle it.  May and June are always a crazy time at universities, so there have been a lot of demands at work.  Also, we've been working on a deck at home, which has used a lot of time on the weekends.

This morning, I had waited long enough and decided to go for it.  First, I siphoned the mead from its 3 gallon carboy into another one. Why did I do this?  There is a fine precipitate sitting at the bottom of the carboy  the result of clarifying the liquid.  It is easily disturbed, and during the bottling step, there can be a lot of movement of the siphon tube.  By transferring the liquid to a separate container first, it is easier to avoid disturbing those fine solids.  It has certainly worked out well in the past.  But this time, I managed to slightly disturb that precipitate and some of it got into the liquid.  It wasn't much, but there was a slight turbidity to the mead that I ended up bottling.  This is frustrating because the liquid was crystal clear before, and it was an avoidable mistake.  I just hope it settles out over time.

I used my auto-siphon to fill the sanitized bottles (pictured below).  The end result was fourteen 750-mL bottles of mead!  There was little extra, so I put it in a separate bottle and placed it in the fridge.  (This was so I could see what it tastes like when chilled.)

(1)  Bottling.  I don't really need to wear rubber gloves 

for this, but I was sanitizing with bleach solutions, and it was 

easier to just leave them on!

Several hours later, I am writing this with a small glass of chilled mead at hand.  First of all, this stuff is strong - certainly stronger than most wines.  You may recall that I estimated the alcohol content to be 15% or so.  It is obviously sweet, with a mild honey taste, and a hint of oak and cedar.  There is almost no acidity, and the finish is surprisingly clean.  And, yes, it is better served chilled, just like most dessert wines. 

When my wife tried it, she immediately looked up at me with her eyes wide, and said, "Yummy!"  This brings me to an important observation: this mead is ready to drink.  One doesn't need to age it for months and months before uncorking a bottle and pouring a glass.

My daughter asked if she could help make labels.  She drew a nice picture of a commercial bee hive.  From her artwork, I thought the name "Sunnyside" was appropriate.

(2)  Homemade bottle label.

Yesterday was summer solstice in the northern hemisphere.  If only I had bottled this a day before, I could have celebrated the longest day like the ancients - with a glass of mead!

Rhubarb Wine: Interim Satisfaction

Twelve days ago, I started the rhubarb wine.  I've been out of town for half of that time.  Today, I got around to checking on the progress.  When I opened the lid on the plastic bucket and looked at the surface, I could tell that fermentation was on the tail end.  There just wasn't a lot of "activity" in terms of bubbles.  I quickly sterilized a 3 gallon carboy and my auto-siphon and got to work racking the wine into a carboy.

Some observations:

1. Specific gravity = 1.012.  The initial s.g. was 1.097.  Therefore, the approximate alcohol content at this point is somewhere between 13.0 and 13.5 %.  (It's getting close to being done!)
2. The colour!  There is a nice peachy pink colour now.  I thought the colour had been totally  bleached by the campden tablets, but there might be something else going on.
3. The taste!  (Naturally, I tested it!)  There was no tartness at all, just a mild rhubarb flavour, along with a gentle grape taste from the concentrate that I added.  This has the potential to be a very nice dessert wine.

Front: Rhubarb wine, with some colour.  

Back: Mead, just prior to adding kieselsohl.

Mead v.1 has been sitting in a carboy for about 12 days as well, and there was a nice build up of lees at the bottom.  I racked it into another carboy and then added the kieselsol, which is step 1 of the finings.  And, I sampled the mead too.  It's getting better!  The taste has mellowed out a little and I think it will be really nice when it is chilled.

Mead at 6 weeks

For the last two weeks, the fermentation rate has been falling slowly.  Two days ago, I made the decision to stop the fermentation.  There was a nice layer of lees at the bottom of the carboy.  The bubble rate was down to 2 per minute.  I reckon that the fermentation probably would have continued for a week longer.  It was the specific gravity that tilted the decision to stop.  The initial specific gravity was 1.120, and it had fallen to 1.019.  Yes, with that final specific gravity, there is probably a small amount of fermentable sugars remaining.  However, from the hydrometer scale, the difference between starting and final specific gravities corresponds to an alcohol content of approximately 15%.  I felt that this was more than strong enough.  If there's a little sugar left, so be it.  It will taste sweeter.

So, I siphoned the mead into a sterilized secondary fermenter, and then added 1 tsp. of potassium metabisulfite and 3/4 tsp. of potassium sorbate, with lots of stirring in between.  Two days later, I haven't noticed any activity, and there is a nice layer of lees that has already settled out.

(1) Mead immediately after racking to the secondary.

After racking the mead, there was a small volume remaining in the primary and in the siphon hose.  So, I sampled it.  It was better than the junk I was served at that barbecue many years ago.  However, the unprocessed mead I tasted had some carbon dioxide in it, which made the taste sharp.  That will hopefully disappear with time.

 (2) Sediment two days after racking.

My plan is to let this sit for the next week or so, and then add the finings to make this beverage crystal clear, and ready for bottling!

Mead at 4 Weeks

In typical OCD fashion, I have taken daily measurements of fermentation rate (bubbles per minute) of the mead sitting in the corner of my home office.  Today is exactly 4 weeks since the start.  The rate this morning was 3.2 bubbles per minute.  So, the fermentation is still chugging along.  I thought it would have finished by now!  (Could this be a case of "a watched pot never boils"?)

Mead primary fermentation at 4 weeks
(It doesn't look any different to the Day 16 pic.)

Mead v.1

Confession:  I don't know much about mead.  The first and only time I tried it was 9 years ago at a barbecue at a colleague's home.  This colleague does not drink alcohol.  A year or two previously, somebody had given him a gallon jug of homemade mead, and it had sat at the back of a cupboard since then.  This particular evening, he decided to coerce his guests into consuming it so he could then dispose of it with a clean conscience.  I sampled it.  It was sweet and had a lot of alcohol in it, and I didn't really care for it.  I did not ask for seconds.  From what I recall, he still had a very full jug of mead when the evening was over.

So, why mead?  What's the appeal?  For me, the most interesting thing about mead is just how ancient it is.  From archaeological evidence, it is the oldest fermented beverage.  According to Wikipedia, forms of it date back as far as 7000 BCE:  http://en.wikipedia.org/wiki/Mead

How can that sort of history fail to stimulate one's imagination?  Just imagine how the discovery of fermentation took place.  Did proto-civilization humans drink mixtures of honey and water?  Perhaps a container of this honey drink was sealed in a pottery vessel, forgotten for a time at the back of a primitive cupboard, and then consumed by some unwitting soul?  Imagine the first time somebody drank a fermented beverage!

Over this last winter, I started thinking about making a batch of mead, just to test it out.  Why not?  There are many mead recipes online, and there seem to be a lot of people out there who really like making and consuming homemade mead.  One of the problems to overcome was where to obtain several kilograms of honey without having to drive all over the country to find a beekeeper (or purchase a large number of smaller containers of honey at Safeway).  We recently took out a Costco membership, and that is where I discovered 3 kg jugs of honey.  I bought two.

For this first run, I adapted the following recipe for basic mead:
http://www.epicurious.com/recipes/food/views/Basic-Mead-201058

Following the standard sterilization procedures, I used a funnel to transfer approximately 4.5 kg of unpasteurized honey (i.e. one and a half jugs of honey) into one of my 3 gallon carboys, already one quarter full of distilled water.  I added honey gradually, stirring in between additions to mix it into the water.  When it was well mixed, I added water to fill it to 3 gallons, and gave it a final stir.  (I did not heat any of the water because I read somewhere that heat can alter some of the natural honey flavours.)  Then, I simply sprinkled a packet of sparkling wine yeast onto the surface, closed the carboy with an airlock, and waited.  The specific gravity of the honey/water mixture was 1.120.  According to the scale on my hydrometer, this is in the starting range for dessert wines (strong and sweet).

(1) Honey and water...

Initially, the fermentation seemed to start okay.  I monitored bubble rates closely over the first day, and was alarmed when the fermentation rate started to slow down at 22 hours.  My initial thought was that the problem had to do with not activating the yeast.  With the regular wine kits I have done, yeast activation was unnecessary; the fermentation took right off when the yeast was simply sprinkled on the surface.  I visited the Wine Kitz store to get another packet of yeast and had a chat with one of the Wine Kitz dudes.  He told me, from extensive experience, that mead was very difficult to start because honey has anti-microbial properties.  In fact, he informed me that if you sprinkle yeast onto neat honey, all the yeast will die.  So, yeast activation was critical.  Back home, I quickly activated a packet of yeast with warm water and added it to the carboy.

The activated yeast certainly performed better, but the bubble rate plateaued at just over 4 bubbles per minute, which seemed very slow.  Next thought: add some yeast nutrient.  I added two teaspoons of this stuff, and the fermentation took off immediately.  You can see this in the following graph.

This graph tells the story of a learning process. The lessons are:

1. Activate the yeast
2. Use yeast nutrient
3. Don't let your children turn off your oil heater (they think they will save you money on your electricity bill, but it also lowers the room temperature and slows fermentation)

The last data point in the bubble graph is from this morning, which is day 16.  It kind of looks like the fermentation rate is leveling out, but it's not over yet.  It may be worth taking a hydrometer reading to check the progress.

Oh, by the way, the aromas coming out of the airlock are just fabulous.  It smells very yummy!

(2) Mead primary fermentation on day 16