Strawberry and Apple TC experiment

[GrandMalt]

I've looked around for recipes that use strawberries, but there don't seem to be many out there. My wife and I live in Egypt, and strawberries are in abundance out here at the moment so we wanted to try making something with them. Having had success with a couple of small-scale TCs using apple juice from our local shop (brewed using yeast washed from previous beer brews) we decided to try doing something with strawberries.

Yesterday morning we pulped the strawberries using a food processor. We then mixed half a litre of apple juice with the thick pulp, and strained the resulting mixture through a fine sieve to extract the juice. The remaining pulp was then mixed again with another half litre of apple juice, and the straining process repeated. Factoring in for the quantity of apple juice we mixed with the strawberry pulp, we managed to get about a litre of strawberry juice from 2kg of strawberries.

This juice was added to the FV (basically an old 7L water bottle with a hole and grommet in the lid for the airlock) along with another 4 litres of apple juice. The mixture was therefore 5 litres of apple juice and a litre of fresh strawberry juice. I then added some yeast I had washed from a John Thompson XXX Bitter. The OG was approximately 1.040, although it was difficult to get an exact reading as the juice frothed so much that I couldn't see the hydrometer clearly. Previous batches of this apple juice and yeast have finished at 0.998, but I don't know whether the strawberries will change that.

The lid of the improvised FV was covered with a bit of cling film (the seal on the water bottle is really bad) and the airlock puched through the lid and through the cling film to burst a hole. This was then put into our homebrew fermentation cooler - basically a plastic storage tub inside a large cardboard box packed with polystyrene and bubbel wrap. We place ice packs inside the storage tub to control the temperature. Ambient temp here in Egypt is about 25'C at the moment, and we can easily knock 5'C off that by using the cooler and therefore control the fermentation temperature.

This was done at about noon yesterday. Last night I played a belated St Patrick's Day gig with the Irish band I'm part of, so it wasn't until this morning that we checked on the process of the brew. Clearly the strawberry juice had quite an effect on getting the fermentation going. The same apple juice has bubbled away quite steadily in the past, but we opened the cooler this morning to find a real mess! The brew had blown the top off the airlock, ripped through the clingfilm, and had spewed a load of pink scum all over the cooler!





We cleaned up the mess, washed and sterilised the air lock again, and refitted it. Within an hour ago the air lock had already begun filling with the pink foam again. I've honestly never seen anything go off with so much power!

In the end we needed to switch the airlocks every 12 hours for the first 2 days, but now it's settled down to a bubble every 15 seconds or so, and the krausen has subsided. We put another 500ml of apple juice in this evening to reduce the headspace and it's seemign quite happy now. Despite us straining the strawberry juice, there's still a lot of sediment in the brew and so I'll aim to let it settle for a while and probably rack it before bottling to try to get it to clear a bit more.

I'll update this thread to let you know how it turns out.

[GrandMalt]

Just an update on this brew. It's been fermenting for a week now, and after the initial spewing of krausen all over the place for the first 36 hours it calmed down a lot. The colour has also changed quite significantly - it's more of a pinky-orange now than the deep red of the initial juice.

The airlock was bubbling regularly every 13 seconds for the past few days, but this morning it was down to every 30 seconds. By lunchtime it was every 55 seconds, and so as it appears that it's reaching the end of fermentation I decided to rack it. There was a good inch of 'crud' at the bottom of the FV, which on rackign appeared to be about 500ml. I've therefore topped up the brew with another 500ml of apple juice.

A sneaky taste suggests that the strawberry flavour has mellowed significantly. Although you can tell there's some soft fruit flavour in there, it's not overpowering and just sits in the fruitiness of the apple quite nicely. Obviously I'm expecting the flavours to mature a bit after bottling and conditioning, but for the time being it's quite a pleasant balance.

I reckon I'll keep an eye on it over the next few days to see airlock action. When this slows down I'll start hydrometer tests prior to bottling. I plan to prime with Sinai clover honey, as it's got quite a lot of sweetness that doesn't seem to ferment out and can take the 'tang' off the sharpness of the TC.

[GrandMalt]

Bottled this one after 7 days in the primary, then racked into a new vessel for 4 days before bottling it today.

OG 1.040
FG 1.002

Primed with clover honey. The colour is a grapefruit pink, and the dregs taste pretty good. Plan to leave it for a couple of weeks before supping.

[trucker5774]

Keep an eye on the pressure. TC can drop to 998 and you have primed at 1002. I usually stop mine about 1020 from an O.G. of 1060

[GrandMalt]

Thanks, Trucker. It had been at 1.002 for three days so I figured it had finished finished, but I certainly thought it a bit strange it hadn't dropped further. Previous TC with the same apple juice finished at 1.000 but that didn't have the strawberries in it. My suspicion is the pure strawberry juice has affected the gravity somehow, but thanks for the warning as that supports my deepest-held fears! Some is bottled in PET and the rest is in glass - I'll keep an eye on it all over the next couple of days and release pressure if it looks like there's a problem.