Category Archives: sulfite

Master Vintner Small Batch Winemaking Part Four

You may remember Master Vintner from such posts as Master Vintner, Your Personal Wine and Master Vintner Part Two: Racking Day. As such you might well wonder, ‘What happened to part Three?’ Don’t worry, all will be explained.

Laid out and ready to go

Laid out and ready to go

Step three and step four kind of run together, so I’m blogging about both of them at once. When we last left our Master Vintner Small Batch wines (Chardonnay, Merlot, Cabernet Sauvignon and Pinot Noir) they were resting comfortably in secondary fermentation. The next step was to . . . READ THE INSTRUCTIONS!

Yes, I keep coming back to the importance of reading. It’s your guarantee of success! A quick read-through let me know that I would have to check the specific gravity and then rack the wine from the secondary to the Little Big Mouth Bubbler again for stirring and fining/stabilizing additions.

I sanitized all of my equipment, took a specific gravity reading (0.992 and rock steady) and then transferred the wine from the jug to the LBMB.

Auto-syphon: how do you live without one?

Auto-syphon: how do you live without one?

Once all of the wine was transferred over (leaving very little behind in the jug–less than a couple of tablespoons of goo) the next step was to add metabisulphite to prevent oxidation (browning and loss of flavour) and prevent bacterial spoilage (going icky).

Sulphite is your friend, and wants you to be happy.

Sulphite is your friend, and wants you to be happy.

Let’s talk about sulphite. It’s one of the most common food additives in use today, and it’s been in continuous use in winemaking for many centuries. It’s in every preserved food you buy and in lots of things you wouldn’t expect (noodles? Check. Frozen orange juice? You bet! Pancake syrup? Sure!) It’s safe and almost completely benign. If you don’t believe me, check out the world’s #1 Authority on sulphite use in home winemaking.

So that’s sulphite taken care of. In it goes!

Be sure to tap the packet: a bit of the powder can get caught in the corners.

Be sure to tap the packet: a bit of the powder can get caught in the corners.

After the sulphite is in we have to stir the wine to distribute it, and to drive off gas in solution. This is crucial to the success of the kit. Carbon dioxide gas is produced by the yeast during fermentation. In a commercial winery this is not much of an issue because they take one or two years to get the wine ready for bottling, and in that time all of the gas escapes. Master Vintner kits are designed to be ready to bottle in just four weeks, so the gas has only a short time to escape from the wine. To stay on schedule we need to aid the process through mechanical agitation.

A stirring experience.

A stirring experience.

I stirred the wine for a full sixty seconds and then added the first fining agent. Fining is the process of dropping suspended material out of the wine so it’s clear enough for bottling and drinking. Common fining agents are either mineral in nature (Bentonite, Silicon dioxide) or a colloid/gelatine (Isinglass, Chitosan) and in wine kits they’re often used in pairs. The instructions say to add the packet labeled ‘Siligel’, a silicon dioxide solution–essentially really finely pulverised beach sand in a liquid and then stir again.

Sharp scissors are an essential winemaking tool

Sharp scissors are an essential winemaking tool

Cut the tip off of the Siligel packet . . .

Squeeze!

Squeeze!

. . . and then another sixty seconds of stirring.

That's what good stirring looks like--get the fizz out.

That’s what good stirring looks like–get the fizz out.

I popped the lid, bung and airlock on again and over the course of the next two days I kept my spoon in handy and stirred the wine again for sixty seconds at breakfast, lunch and dinner–since it’s right in my kitchen it’s an easy step to take right there when you’re already making a sandwich or preparing your Sunday roast.

After two days of stirring it was time to go on to Step Four, Stabilizing and Clearing. Since it’s almost exactly like the last step, I’m putting it all into this one long post to keep things clear.

I cleaned and sanitised all of my equipment, checked my specific gravity (yep, still 0.992) and did my next addition, Potassium Sorbate. Sorbate is a bacterial suppressant. It doesn’t kill or even annoy spoilage organisms, but rather keeps them from breeding, which is crucial to the whole process of fining and stabilising: you use sulphite to stun/kill some of the yeast and any other organisms, you use the fining agents to sweep all of the micro-organisms out of the wine, and then you use sorbate to keep any of them from breeding back to the point where they can affect the appearance or flavour/taste of the wine. Sorbate is used in a lot of foods, condiments and even in beauty products and health food supplements, and is found in some berries (blueberries and Mountain Ash) as well. So, in it goes, with the first step being to dissolve it in a tiny amount of warm water.

It's a teeny amount and it dissolves almost instantly.

It’s a teeny amount and it dissolves almost instantly.

And then to stir that into the wine.

Everybody in the pool!

Everybody in the pool!

Next step is to add the ‘liquigel’, a clever contraction of ‘liquid gelatine’ and the final fining agent.

Snip!

Snip!

Squirt in carefully.

It's pretty sticky: make sure it all comes out of the packet.

It’s pretty sticky: make sure it all comes out of the packet.

Once everything is stirred up and all additions are done we need to top up the wine to the one gallon mark again. Don’t worry about diluting it: if you’ve been racking correctly you’ll be adding less than a cup and a half (350 ml) and the kit is actually formulated to accommodate this extra water.

Topped right up.

Topped right up.

After that it’s back on with all of the lids and airlocks and onto the counter to rest for six days until the wine is clear.

Soon, my pretties . . .

Soon, my pretties . . .

So far this has been the easiest, smoothest winemaking I’ve ever done: the one-gallon size makes doing one kit so easy, so quick, and so simple that doing three more at the same time doesn’t feel like work at all–it feels like a fun hobby leading to a great end–wine!

The Enemy Without

fruit-fly

A face only nobody could love

Summer is here and for winemakers that means one thing: the inevitable return of our sworn enemy, Drosophila melanogaster, the common fruit fly. Minute little flying monkeys of doom, they’re hard to exclude from your winemaking areas, and while they’re easy to kill, by the time you’ve swatted one thirteen more have materialised out of thin air, looking for a free meal—females lay 400 eggs each, and they mature in as little as 7 days!

The reason why we need to be concerned over the little monsters isn’t just that they’re unsightly and chewy when you discover one inside a mouthful of Chardonnay. No, it’s their other name we need to think of, ‘Vinegar Fly’. The little blighters are filthy with acetobacteria, the organism that turns our delicious alcohol in to vinegar.

fly infestation

Time flies like an arrow. Fruit flies like a banana.

How to combat ‘em? First, understand that they don’t eat fruit: they eat mainly yeast. When they smell carbon dioxide and alcohol, they think it’s a piece of rotting fruit where they can lay eggs and get a delicious meal. When they smell a fermenting carboy, it’s their equivalent of a Vegas buffet ten thousand miles long.

Anybody who has ever worked as a bartender over the summer months knows the sad and icky truth: you come in for the first shift of the day and any bottles that have been left with an open pour-spout (‘speed spout’) overnight will need to be poured through a coffee filter to extract the little winged corpses from their watery graves. If a fermenting carboy smells a buffet, and bottle of vodka smells like ten tons of chocolate cake.

Step one in managing these horrific little pests is exclusion. You can’t keep them out of your house and your fermenting area, so you’ll need to exclude them from the wine itself. Always do covered fermentations. The commonest fermentation vessel used to start kit wines in the US is a 7.9 gallon (30 litre) bucket with a tight fitting lid and a port to plug in an airlock. By keeping the wine sealed and airlocked, you’ll deny entry.

Second, when your wine goes to the carboy, make sure you keep that airlock topped up with water. Some folks use sulphite, and while that’s mostly harmless the sulphite usually oxidises off in a few days into plain water. Other folks want the sanitising power of alcohol and load the airlock up with Everclear or grain alcohol—this only attracts the enemy!

Third, you’ll need to wipe up every single little tiny spill of wine or juice immediately, and sulphite the area to prevent any residue from getting a yeast film going on it. Then make sure you wash your cloths or discard your paper towels in a tightly sealed receptacle—the cloth used to wipe up the juice will become a source of attraction.

Fourth, if you have to wash all racked primary fermenters or carboys (those with lees and even a small amount of cloudy wine in them) immediately. If you can’t get to the right away, pop the bung and airlock on again.

Fifth, if you filter your wine (always a good idea—I’ll talk about that in a later blog) break down and clean your filter right away, and seal the used pads in a plastic bag before discarding them: they smell just dandy to fruit flies.

Flypaper only works on fruit flies by accident. Plus, some of the stuff is toxic as all get-out, and not good for winemaking areas. You can set up a wasp trap (available from hardware stores) for them. Normally they’re filled with fruit juice or other sweet liquid, but that doesn’t impress a fruit fly. Fill it with the magic formula: apple cider vinegar with a couple of drops of liquid dish soap. The apple cider vinegar drives them to a gustatory frenzy, while the dish soap removes the surface tension of the liquid: when they fly in and hit it, they drown right away—poof!

You can also, check out natural pyrethrin-based insecticides: they’re made from plant oils, are mostly safe and can be used in food prep areas. Never use any other kind of insecticide around wine or food prep areas! Triple-check to make sure you’ve got pyrethrin and not the synthetic pyrethroid, which is much more persistent and killier. Pyrethroids are bad for the environment and can be toxic to children and pets, especially kitty-cats, who lack the enzyme to break them down, and can rapidly succumb to pyrethroid toxicity. No kitty should be collateral damage to a fruit fly!

It should be noted that cleanly made wines that have fully fermented and are sulphited to an appropriate level (follow the manufacturer’s instructions) are fairly resistan against colonisation by acetobacteria. Sulphite in particular is a good bacterial inhibitor for this organism.

But there’s always that chance: a missed sulphite addition, a little extra oxygen pick-up in fermentation, one lone fruit fly wings in and . . . well, that’s thirty bottles of wine you can’t even pour on your salad (wild acetobacter fermentations make a kind of vinegar that tastes mostly like nail-polish remover).