Batch #1 - "Pinja Kiljunen"

Now its time for us to show the process behind making kilju. This is batch #1, that we ended up naming "Pinja Kiljunen," after the Spanish word for pineapple - piña. Like the name suggests, the theme of this first experiment is pineapple.


The ingredients are quite simple:

• 1 Pineapple (1.66kg)
• 125ml lemon juice (4 lemons equivalent)
  
• 1.5kg sugar
• 4l water
• Drinkit Turbo Speed yeast (dosed according to package instructions)

As with any project like this, a proper hygiene etiquette is essential. With kilju, its not necessary to be anal about cleanliness, but common sense and a bit of effort will pay off. All the little bits of equipment are easy to sterilize by boiling them, and the same water can then be used to swirl the fermentation vessel into microbe-free goodness.

Then the pineapple. First we peeled the pineapple using a potato peeler, and then chopped it into small chunks in preparation for the final pulping with a blender. It's good to get the fruits as small as possible to make their sugars available. Normally when brewing with a standard 30l vessel, we would settle for just chopping up the fruit. It remains to be seen whether blending gives any benefit. A nice trick is to pop the fruit bits into a bag of cheesecloth or somesuch, so they are easy to remove. We didn't bother, this kilju will be with pulp included.

The sugar is best dissolved into boiling water. A smart kilju-brewer will not use too much boiling water at this point though, since in the end we want the mash to be at a temperature suitable for introducing the yeast (usually 25-30'C). Once the sugar is dissolved, everything goes into the fermentation vessel, the sugar water, the pineapple mash, lemon juice, and enough cold water to bring the total liquid up to the four liter mark.

At this point we realized a little mistake. We failed to account for the fact that all the ingredients like sugar and pineapple also add to the volume, and ended up with entirely too much mash. Though the fermentation vessel has a 5l volume, there needs to be an airspace, so the effective capacity is perhaps 4l. If there isn't an adequate airspace, the fermentation will push kilju out of the trap, or even blow the lid off - not good. No problem though, we stuck a trap on top of a 1.5l soda bottle, siphoned some of the mash into it, and divided up the yeast accordingly.

When choosing the yeast, we looked at the time it'll take to finish fermenting according to the package. The selection ranged from one that claimed 24h, some two and three day affairs, and the one we chose. Ours claims to finish in 3 to 7 days. The fastest yeasts generally add unpleasant tastes to the kilju, and ferment aggressively. We figured an aggressive fermentation would just blow the lid off our pot, so we went with a slower choice. Of course, we only noticed the warning on the package about aggressive foaming when we got back to the lab. No big deal here either, we'll just keep a close eye on the vessels and let gas out as necessary.

After the yeast went in, we gave everything a stir, closed the lids, put water into the traps. In a week or so, we should have delicious kilju.