Can You Second Ferment Kombucha in Plastic Without Any Problem?

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You taste the kombucha, and it blesses your taste buds with its effervescent, slightly sweet, and tart flavor. But, this is not the taste you desire! You need to wait for more to enjoy the fizzy and bubbly flavor. 

Perhaps!  You are about to start the second fermentation and get confused about which bottle to choose. Unlike primary fermentation, can you second ferment kombucha in plastic?  The answer is yes.

You can second ferment kombucha in a plastic bottle – if it is thick, food-grade quality, and composed of PET or HDPE. Second fermentation doesn’t increase acidity, so the bottle remains integral. Besides, the fermentation takes little time, which doesn’t trigger the plastic to leach out chemicals. 

If you want to know further about this, keep reading our in-depth article. 

Can You Second Ferment Kombucha In Plastic?

can you second ferment kombucha in plastic

Brewing kombucha is fun! It is a natural process. Here the organisms that come into play can thrive in the plastic.

Still, people get skeptical because when this tea comes in contact with plastic, it elicits harmful chemicals.

But, the good news for you is it is safe to second ferment kombucha in plastic without any problem. Are you excited? Let me justify the statement. 

Second fermentation entails flavoring the unflavored and carbonating non-carbonated kombucha. It takes one to four weeks to complete primary fermentation. In the case of F2, it takes only 3-4 days.

That means the tea remains in contact with plastic for a short period. So, no chemical reaction takes place. Just make sure you have it quickly after the second time brewing. 

Another thing that triggers the release of toxic products is acidity. In contrast to primary fermentation, the pH level rises in secondary fermentation.

However, don’t use the same pot for the second time brewing. The container can break down because of the high acidity, leaving toxic chemicals behind. 

Point to be noted, plastic bottles with loose caps can deteriorate the flavor. So, make sure you select a plastic bottle with tight lids.

What Else Can You Use For Second Fermentation

can you second ferment kombucha in plastic

For the second time brewing, you need to have a good quality, thick bottle which can trap the air. You need a top that can seal the container and make it airtight. 

Otherwise, it will leak out liberated Carbon dioxide from kombucha, and your kombucha will fall flat.

Don’t worry! There are plenty of bottles designed to achieve airtightness. We have shortlisted a few of them below: 

1. Beer Growlers

This 64 oz Beer growler has become a popular choice among homebrewers. Thanks to its leak-proof threaded poly cone cap!  It contains a polyethene cone inside, which, when twisted, holds the bottle’s lip and gets tightened, forming the cone shape.

It locks the pressure and thus, helps build high amounts of carbon dioxide. You can use Stanley stainless steel beer growlers, offering leak-proof lid and a large capacity.

2. Old Wine Bottles

You can recycle the old wine bottle for the second fermentation. Make sure it has a cork or wine stopper to create an airtight area.

However, you may not enjoy flavorful tea of different ingredients due to its large size. But it’s an ideal choice for one flavor tea in large quantities.

You can always buy old bottles if you don’t have them; just click here.

3. Mason Jars

Mason Jars are a suitable alternative to plastics for kombucha fermentation. They have manageable sizes, which are easy to oversee and clean. Use Ball Mason Jar

However, as it doesn’t have a neck, it’s prone to explosion. Additionally, be extra-attentive, fitting the jar’s cap; otherwise, your tea will be less-flavored.

Use Ball Mason Jar; easy to attach, clean, and less risky.

4. Steel Container

A high-grade steel container is ideal for kombucha brewing – safe, easy to clean, lightweight, durable, and readily available. Moreover, as homebrewers know them, they are more comfortable with these containers. Try Oggi Stainless Steel Container for a delightful kombucha.

Is Plastic Good For Primary Kombucha Fermentation

Is Plastic Good For Primary Kombucha Fermentation

So, can you ferment in plastic bottles? People invariably ask this.

Well, you should not use plastic for the primary fermentation of kombucha for two reasons – long duration and decreasing pH.

Constant contact of kombucha with plastic produces hazardous material called BPA. It may cause cancer, heart disease, and other health hazards.

The Symbiotic Culture of Bacteria and Yeast (SCOBY) is the alarming news that consumes sugar and later converts it into acid. So, if the toxic product is released, the SCOBY also eats them.

These will make them weak and ultimately cause death to the harmless microbes. The worst part is bad bacteria can thrive in the same media, which is harmful to health!

Though many stable, BPAs free plastic bottles are available in the name of PET and HDPE, they can’t confirm complete protection. Therefore, it’s wise to avoid them. Moreover, when 100% safe alternatives, glass, are available, why take risks for your SCOBY? 

Why Is Glass So Popular

Using glass bottles for kombucha fermentation is a popular choice for its FDA approval and other numerous advantages. Let’s check out why it gains this immense response-

  • All-natural and composed of good quality raw material. 
  • It doesn’t release any toxic substances i.g BPA lead or other heavy metals.
  • The airtight space allows CO2 production. 
  • You can recycle it. 
  • Scratch-resistant.
  • Good quality materials, so no health hazards
  • Available in different sizes and customizable.

Picking The Right Container

Picking The Right Container

Choosing the correct container has a lot to do with the outcome of your batch. The fermented tea is placed four times in the jar – during F1, F2, after fermentation, and finally for storing.

Therefore, your kombucha brewing may go wrong if you use any low-grade, thin, poor metallic bottle. 

So, what to see while selecting the container? Let’s check out all the facets to get the perfect pot in hand : 

1. Types of Container

You have several kombucha fermentation options, but glass is the most suitable. However, if you are still confused, here is the preference suggestion-

  1. Glass
  2. Beer growler
  3. Stainless steel
  4. Old wine bottle
  5. Plastic (less suitable for first fermentation)

2. Opening size 

It is essential to select a jar through which your hand can easily pass for primary fermentation. The standard measurement for this is 5″-6″. 

However, you have to restrict airflow in secondary fermentation.

3. Capacity 

It depends on how much you want to drink from a batch. For example,

  • The smallest batch is around 16 oz.(3 bottles). Here the SCOBY takes up most of the room, leaving only half gallon kombucha to enjoy. 
  • For 1-2 people, you should go for a gallon. It’s a popular choice, producing 6-7 bottles of kombucha from a batch.
  • If you have a big family who loves to enjoy this fizzy drink, go for 2+ gallons. Each gallon will make 6-7 bottles of kombucha, enough to enjoy this summer. 

4. Spigot vs. Non-spigot 

The spigot serves as a tap, helping you draw out your tea easily whenever you want. Also, you get rid of the hassle of touching SCOBY or removing the cover over it.

However, not all; many spigots often get clogged or broken during cleaning. However, not every spigot has this issue. A plastic spigot never gets clogged but may break if you clean it carelessly. 

How To Ferment Kombucha

Kombucha brewing is a super easy and fun task if you know the basics. We break down the process into two parts : 

1. Primary fermentation 

The basic requirements of primary fermentation are-


  • First off, pour two cups of water into a small pot and boil for a while.
  • Add tea, and boil them for 5-10 minutes. 
  • Add sugar and stir the mixture until it gets dissolved. 
  • Now, place the entire thing into a gallon brew jar. 
  • Add cool water in a way that has at least 3 inches of breathing room left. During this stage, the temperature should be around 85°F.
  • Again stir your newly started SCOBY.
  • It’s time to check the pH. For this, draw out a small amount of tea and deep the strip into it. The ideal pH for it is 11. So, if the reading is below or equal to 4.5, try to step into 11. But, if it is above 4.5, add some vinegar until it reaches 11.
  • Cover the jar with a breathable cloth and secure it with a rubber band. It keeps the bugs away and helps support fermentation. 
  • Now place the jar in a corner away from sunlight for one-three weeks.
  • After one week, taste the flavor. It will have a slightly sweet and tart taste. However, over-sweetness indicates that the tea needs to be fermented more. 

2. Secondary Fermentation 

The first step of the second fermentation is to know that you are done with primary fermentation. Once you get to know, follow the instructions given underneath : 

  • Clean the selected bottle properly with distilled white vinegar
  • Flavour your kombucha – just like a painter adds colors to paint his canvas – No rules here. 
  • A simple example may help you, for a 16 oz jar: you can fill up the jar with ⅓ of juice or fruits,1-2 TBSP herbs, and last ⅛-¼ with spices. 
  • You can keep 1.5-2 cups of this tea as a reserve source to start your next batch. 
  • Now, pour each bottle with kombucha and tightly seal it with a cap for fermentation. Leave it for 1-10 days. 
  • Open the cap every day to check out the progress and prevent over carbonation. It is called burping.

This is all! Do follow the instructions and sip out the kombucha you want. 

How Long To Wait For Second Ferment For Kombucha

Based on the temperature you maintained, it takes 7-21 days to complete the primary fermentation. The best way to know whether it is done is to taste the flavor. Once the primary brewing is done, you are ready to go for the F2. 

You might be interested to read also our another comprehensive article of: How Does Fruit Ferment Naturally – Facts About Fruit Fermentation


  • Can I put my kombucha in a plastic bottle?

Yes, you can put kombucha in plastic bottles. But, it’s the last option. When kombucha remains in constant contact for a long period with plack, it leeches harmful chemicals. 

  • Are our plastic lids safe to use for kombucha fermentation?

Kombucha requires oxygenation during primary fermentation. That’s why breathable covers only allowed for F1. You should not use it during the second fermentation as it fails to provide airtightness.  

  • Should I always use airtight containers mandatory for fermentation?

Airtight containers are mandatory for only the second fermentation of kombucha. The co2 produced during the first fermentation needs to get out of the jar. So, a breathable cover cloth is mandatory for F1. 

Take Away

Kombucha – the tasty, healthy, fermented tea is fun to make. However, most homebrewers ask one common query: “can you second ferment your kombucha in plastic?”

Plastic is not recommended for the primary fermentation of kombucha. However, for the second fermentation, you can use thick, good-quality, air-tight plastic. Although you are allowed to use it, we suggest you try it out as the last option as there are plenty of other completely safe and secured options available – glass jars, stainless steel, etc.

So, have a happy fermentation, and enjoy this fantastic flavorful tea with friends and family!

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