I have a friend named Nate. The first time I heard about him, I was told he was brewing beer in his bathtub.

I was intrigued.

Nate also makes wine.

Nate is also a scientist. This lead me to believe that wine making is over my head. But it turns out it’s not really.

I spent some time with him this Fall while he made a batch of wine for his cellar and decided I’d give you a little “how to.” Nate recommends you also get a good book on wine making in addition to my sketchy tutorial. I’m not sure why he suggests that. Did you think I wouldn’t do it right Nate?




Hello Nate, are you there?

Here goes!

Step 1: Pick the grapes (200 pounds in this case)

Step 2: Crush and de-stem the grapes

Some people add diammonium phosphate, which is a yeast fertilizer. You use different kinds of yeast depending on the kind of wine you’re making. The fermenting happens faster when you use cultured or store-bought yeast. The problem is that sometimes you get a less interesting wine in the end so some people use naturally occurring ambient yeast.

Step 3: Primary Fermentation

Let the buckets ferment. These buckets did for two weeks. The naturally occurring yeast on the grapes will begin fermenting in about 2-3 days. You can smell it and you can see it bubbling. By about the 5th day it was fermenting vigorously in this case. This will vary depending on the temperature.

A raft of grape skins and seeds float to the top and you’ll punch it down daily.

You can start to smell the alcohol. Sometimes you’ll see fungus, which you can skim off.

Here you add sulfites. Sulfur protects damage to the wine by oxygen, and helps prevent organisms from growing in the wine. This allows the wine to “last longer” which lets it age and develop complex flavors. If you didn’t add sulfites, the wine would turn into vinegar in a matter of months. With natural yeast you might shoot for 30 parts per million free SO2.

The longer it spends fermenting, the more spicy flavors you will get. The danger is that it will begin to taste like stems. (Or rather, extract too much tannin).

Step 4: Pressing phase

Pour the grapes into a press. Press and let the juice pour out into buckets. There are different sized presses depending on how many pounds you are pressing.


Test with a hydrometer and see what the percentage is.

The grape here was originally at 23.5 brix (some California cab or zin grapes will get to 26-28). An equal volume of grape juice will weigh 9% more than an equal volume of water. It should become less than 0% which means you get almost all of the sugar out. (Alcohol weighs less than water).

Throw the grapes in your compost pile.

Step 5: Secondary Fermentation

The grape juice will be in secondary fermentation for about one month. A layer of “lees” will form at the bottom–dead yeast and other fibrous bits. Let it all float down to the bottom, yeast bodies aren’t the tastiest things in the world.

Step 6: Racking

Pull all of the wine off the top using a siphon.  Put it in a glass carboy or an oak barrel.

Then you’ll add oak chips. If you have an oak barrel to add the wine to, that’s the best option. But oak chips is the second best. Oak powder is another option, which works even faster but probably doesn’t produce the best taste of the three options.

The wine will be with the oak for a year and will suck the “oak essence” out of the chips or the barrel.

Step 7: Bottling

Siphon all of the juice off of the sediments into a bucket. If you use a bottler, it will suck exactly 750 ml out for you, otherwise you’ll have to measure.

Then you cork it and label it and then you wait another year.