Introduction: Rhubarb "POP". Rhubarb "POP" - is it akin to sparkling wine, or a sweet carbonated pop?  Well, kind of both.   This beverage has a low alcohol content (0.05 percent), and is quite sweet so it is more of a fizzy desert wine.The beauty of this stuff is it can be ready in as little as 3 days, though commonly 2-3 weeks is best for fizz and a stronger flavour.  Sure it's not ready in a couple hours, but good things come to those that wait.  Think of it as slow cooking with fermentation as your form of heat.   I'm not really after alcohol - I am wanting the bubbles provided by the wild yeasts to carbonate the beverage. The alcohol content is about 0.05%, so this would be similar to a de-alcoholized wine - so safe for the kiddies, or that certain in-law who always has one too many!  In theory, it can be fortified two ways:  it can simply be allowed to sit longer and have the natural wild yeasts do their thing, or you can cheat and add some commercial yeast.As I am not really a drinker, pop it is for me. DISCLOSURE: This Instructable was actually started back in May, 2011.  This may sound odd, but I usually write my Instructables before I even start them; its what I do.  Kind of like one of those stories where some one builds and takes apart a motorcycle or a clock in their head a thousand times first, then  the actual build goes off without a hitch as they have already made the mistakes in their head.  If you look back through some of my old Instructables like the Coffee Making R2D2, or my Analog LED table, they were all built this way.  The point of mentioning this is, it doesn't always work out like the above scenario.  Mistakes do happen. Back in 2011, my first batch looked like slimy swamp water and had a similar smell. What went wrong? I'm not sure.  I used plastic coke bottles which you are supposed to be able to use.  Perhaps they weren't clean enough?   Perhaps no wild yeast was present?  Perhaps I brewed it too long?  Suffice to say, that was my last effort at fermentation until 2016.  So for me, reattempting a failed Instructable after 5 years is a huge step out of my comfort zone.  But I just had to try it one more time!   Step 1: Supplies. Hardware   Large clean food grade bucket:  I used a 18.9 liter water bottle - the kind you get for a office water cooler         Strainer         18 sterilized Home Brew type beer bottles, or  you can use empty plastic pop bottles (See "Disclosure" on the front page).      Measuring cups         Sharp knife and a cutting board.   Several packs of cheese cloth.Foodware10 liters of water.  *Must be chlorine free - So either buy it, or boil it off.      4 lemons juiced, plus the zest - about 1 cup of juice.   5 cups rhubarb - chopped 1/4, or about 4 lbs.      3 cups white sugar.         1 cups of cider vinegar.  Step 2: Harvest and Freeze. How you obtain your rhubarb is up to you. Hopefully you can pick your own, but if not, let social media be your friend!  Come spring, most people have so much rhubarb that they can't give it away.  Use your local Facebook buy and sell to score some free rhubarb, or at least you will find it for a much cheaper cost than the grocery store.When harvesting, never take more then half the plant or you can stress it too much.  When the stems are at least 1 inch wide at the base, gently wiggle/pull it from the base.  It will come away cleanly.Give the stalks a quick rinse in the sink and trim off the leaves if you have not already done this.  They are toxic, so there must not be any leaves included in the mixture!Slice into 1/8 slices - you could use a mandolin, food processor or just a nice sharp knife.Bag and freeze for at least 24 hours.  The freezing will help break down the cell walls in the rhubarb and more juices will be released.  This will give you more flavour, and in theory, a deeper pink shade. Step 3: Scrub-a-dub-dub. While your rhubarb is freezing, take this time to scrub your bottles.  I used glass bottles with compression fit stoppers with the brand name 'Ez Cap', also known as "Lightning Tops."  You can use plain old 1 or 2 liter Coca Cola PET pop bottles. Back in 2011 I tried using these PET bottles and it didn't go too well.   I'm not sure if I didn't clean them well enough, or they didn't seal properly, but either way, the resulting brew was goo.  So my advice would be to take your time to clean them well, to rinse thoroughly and then, for good measure rinse again and allow to dry.Note per the EZ Cap bottles:  I found mine via a Facebook buy and sell as I live in the middle of nowhere.  You can occasionally find a small batch brewery that uses these bottles as well, and you may be able to obtain them there.  Step 4: Measure Twice, Combine Once... & Shake, Shake, Shake. This part is rather simple!   Add everything on the Foodware list and stir.  Simple as that!And just so you don't have to go back to a previous step, here are those ingredients again:10 liters of water- must be chlorine free.  So either buy it, or boil it off.      4 lemons juiced, plus the zest - about 1 cup of juice.     5 cups rhubarb - chopped 1/4, or about 4 lbs - Defrosted!1 cup of cider vinegar.     3 cups white sugar.Note:  If you used a water jug like I did, it can be quite an ordeal getting all the rhubarb in, so be prepare from some deep breathing to deal with the possible resulting frustration.  I have heard that others have used a large Tupperware tote in order to avoid this arduous task.  Step 5: Let It Rest. Find a spot where it can just sit; not too hot, not cold.  Mine sat in my kitchen, under my stereo.    After 2 days you're done.  If you go 3 days, you run the chance of it spoiling.   Perhaps back in 2011 this is what happened.Note the colour - as it sat, it became darker.   Step 6: Strain, Strain, Strain. Pour mixture through a large strainer to remove the big chunks of rhubarb. *Set those aside for the Crumble recipe that is included at the end of this Instructable.*  Next, run it through a strainer lined with cheese cloth.     Do it again, and again and again.....     In total, I strained it six separate times.  Each subsequent time that I re-strained the mixture, I added an additional layer of fresh cheese cloth to ensure a clear and delicious final product.No one likes chunky "POP" after all. Step 7: Bottle & Then Forget About It.... Bottling the filtered brew is simple with the EZ cap bottles: simply pour in the mixture and put on the lid.   Make sure to leave the neck mostly empty, and....done!Forgetting about it is another story.  After 3 days we popped open our first bottle.  It was super syrupy, and only a tiny bit fizzy, but the flavor was soooo good - a promise of things to come.  It tasted similar to strawberries at first, followed by a lemon tang and followed up with the peculiar flavor of rhubarb. The rest of the bottles sat in a large tote in my kitchen.  Over the next 2 weeks, we sampled a bottle every 3 days.  Once we reached the 2 weeks mark, I put the rest of the bottles in the fridge.  This stops the fermentation process and locks in the flavor and the fizz!Safety Note:  The bottles I used are tough. They are made to contain pressurized fermented beverages.  Regular wine bottle cannot be used, as they will explode.  Even with my tough bottles, I laid a heavy towel over the bottles in the tote. Perhaps find a safer spot then I did...  Step 8: Drink!. This is such a simple recipe!  The 2-3 weeks is really for the bubbles to develop, and for the freshest flavor to be attained.   Longer than that, and the pressure could build up to such a level that the bottles could explode!  On the other hand, it may be interesting to keep a couple bottles aside to see if they develop a higher alcohol content.  Just make sure to store it somewhere safe though.  When you pop the bottle, it will make a satisfying "POP" sound,  and then the scent of the rhubarb will hit you as it's quite fragrant.   As you fill your glass, it will foam, but only a little.   This "POP" may be "soda-ish" but it's still made with wild yeast which yields a delicate bubble.  This beverage is best served in a classic sparkling wine glass as it yields the longest lasting bubbles - the top of the glass curving inwards focuses the scent, and, additionally, preserves the carbonation longer.  The taste of lemon clings to the sides of your tongue, while your brain is tricked into thinking your smelling baked rhubarb pie - it's incredible! Near the end of the evening, gone were the delicate glasses, and out came the hardy mason jars for it to be consumed while relaxing in the very location where this all started - my garden.  Time to make another batch... Step 9: Bonus Step - Rhubarb Crumble With the Left Over Fermented Rhubarb!. Did you save the rhubarb after you strained it?  Yes?  Good!Get a baking dish, (a 9 inch square tin or similar vessel will work), and fill it roughly 2 inches deep with your left over rhubarb mash.    In another bowl combine:     1 cup of flour    1/2 cup of oatmeal    1/2 cup of white sugar    1/2 cup of brown sugar (packed)    Pinch of salt    1 Teaspoon of vanilla    1/2 Teaspoon each of cinnamon, nutmeg and ginger   1 cup of butter or margarineMash it about with your clean hands until crumbly.  Yes, you can use a spoon, but your hands work just fine.    Spread the crumble on top of the rhubarb and dot with butter or margarine.    Bake at 375 degrees for 35 minutes or until golden brown.     Serve warm over scoops of ice cream.  Enjoy! Step 10: .