SCOBY vs. Pellicle vs. Mat — What’s the difference?

Mother, jellyfish, pancake, kombucha culture, pellicle, so on– the many names of the cellulose flapjack that turns tea and sugar into kombucha. But most kombucha freaks, including all of us here at Raw Brewing Co, know it as a SCOBY or (“Symbiotic Culture Of Bacteria and Yeast”) or a pellicle. 

And first-time kombucha drinkers might be a little freaked out to meet the Mother — “ew, what is that? Is it okay to drink?” We get it, meeting mothers can be a bit intimidating, but yes it’s okay to drink — and it’s delicious. While the appearance may be a little off-putting (until you get to know her), the scoby is a beautiful patty of life forming goodness! Without the mother scoby, kombucha would just be some dank and moldy old sweet tea.   It’s the magic of the bacteria and yeast symbiotically converting the sugar and tea that brings it to life as the beloved fermented beverage.

As an aside, SCOBY (capitalized) and scoby (lowercase) are the exact same thing — and both are correct in our book.  At Raw Brewing Co., SCOBY feels a little loud in our mind — and nobody really wants to get yelled at by mother, so we tend to use scoby far more often.

What’s the difference between a pellicle and a scoby — and a mat?

First, a pellicle and a mat are the exact same thing, but pellicle is the proper term — so we will use that moving forward.

Next, as some things in brewing science are not greatly explored, terminology isn’t always agreed upon or fully established, and kombucha pellicle and scobys are a good example of this.  While the terms pellicle and scoby are used interchangeably in the kombucha world, most experienced brewers understand they aren’t exactly the same.

A pellicle is a biofilm in the form of a sheet on the surface of a fermenting liquid. that consists of an aggregation of

• cellulose;
• proteins, and;
• polymers, created by bacterial or mycelium (yeast) growth

And they are common in all sorts of fermented products, including vinegar, wine, beer, and of course kombucha and more. The pellicle is the floating layer that forms on top of your brew that most people refer to as the scoby — while mold can form on your pellicle (if pH is off, if proper brewing temperatures are not held, or if it goes long periods of time without feeding), it is not formed by and should not be confused with mold.  If you’re unsure whether or not it’s a pellicle or mold (or both) forming in your brew, and need some help figuring it out, checkout our Is It Mold resource.  To learn more about pH and proper brewing temperatures, checkout our Kombucha & pH and our Kombucha Fermentation & Temperature posts.

So what’s the difference between a pellicle and a scoby?  You know how all squares are rectangles, but not all rectangles are squares?  In the kombucha world, in a technical sense, it’s kind of the same: all pellicles are scobys , but not all scobys are pellicles.  In a practical everyday sense, these terms are used interchangeably — and when most people are referring to a scoby, they are generally referring to the pellicle.

Remember that the pellicle is full of massive loads of the beneficial bacteria and yeast that work together as a symbiotic culture your brew needs to thrive.  So by the definition of a scoby (symbiotic culture of bacteria and yeast), it absolutely fits right?  And like all living things on our planet, a fresh pellicle is comprised mostly of water (or in the case of kombucha, supercharged starter liquid with enormous levels of bacteria and yeast).  Now on to starter liquid: by that same definition, starter liquid also fits the definition of a scoby — right?  Because it too has the same bacteria and yeasts!  But starter liquid is most certainly not a pellicle.  Together, the pellicle and starter liquid come together to become your kombucha culture.

When talking about your culture. on the whole, the pellicle and starter liquid serve two distinct functions.  Starter liquid serves to bring down pH to safe starting levels and provide an initial load of bacteria and yeast to your new brew.  Whereas the pellicle from your old brew serves like an immune system for your new ferment — loading up your brew with even more bacteria and yeast — and protecting it from foreign invaders. 

Scoby vs. pellicle — which word should you use?  As stated above, these terms are used interchangeably throughout the kombucha world — even here at Raw Brewing Co.  So either term works.  But if you want to be a booch master, you should definitely understand the difference. 

How does the SCOBY work?

At a basic level, kombucha fermentation works like this: yeast eats sugar and turns it into alcohol, then bacteria eat alcohol and turns it into beneficial enzymes, acids, more probiotic bacteria, and all the good stuff in kombucha your body wants.  And controlled fermentation processes like kombucha brewing have been practiced by humans for nearly 10,000 years. 

What is the pellicle made of, and what’s its evolutionary and practical purpose?

The pellicle contains everything listed above, but is made mostly of bacterial cellulose — a type of cellulose that is produced by certain bacteria.  It is produced by the bacteria as a structural component in their cell walls, and it plays an important role in their survival and reproduction.  The main function of bacterial cellulose is to provide the bacteria with a strong, rigid structure that protects them from external threats and helps them maintain their shape.  Additionally, bacterial cellulose helps the bacteria to attach to surfaces and form biofilms (the pellicle), which are made up of a network of long, thin filaments of bacterial cells that provide the liquid (and the microorganisms living in it) with additional protection and allow them to better exploit their environment.  Overall, the evolutionary purpose of bacterial cellulose production is to help bacteria survive and reproduce in a wide variety of environments.  Practically, this means it increases your brew’s overall resilience and helping to protect it from outside invaders.

Why is it important to include the pellicle from the previous batch when making a new batch of kombucha?

It is important to include the pellicle from the previous batch when making a new batch of kombucha for several reasons.

1. It helps jumpstart fermentation:  First, the pellicle contains massive loads of bacteria and yeast that are important for the fermentation process. These microorganisms are responsible for converting the sugars in the

   tea into the various acids, alcohols, and other compounds that give kombucha its unique flavor and health benefits. By including the pellicle from the previous batch, you are ensuring that your new batch of kombucha will contain a high initial load of microorganisms to jumpstart fermentation.

2. The pellicle functions as an immune system for your brew:  Yes, even the old pellicle can help to protect the microorganisms from external threats, which can help to ensure the survival of the

   scoby and the success of the fermentation process.

3. It helps increase fermentation speed:  Increasing the number of microorganisms at the start of the fermentation process increases the speed of the ferment, and because there’s so many in the pellicle, including it in your brew will generally cut down on fermentation time and finish your kombucha quicker.  That means you can drink it quicker!

Overall, the pellicle plays an important role in kombucha fermentation by helping to protect and support the growth of the bacteria and yeast. By including the pellicle from the previous batch when making a new batch of kombucha, you can ensure that your fermentation will be successful and produce high-quality kombucha.

Can you make kombucha without including the pellicle from a previous brew?

Making kombucha without the pellicle from a previous brew is possible, but it is more difficult to achieve a successful fermentation, so we don’t recommend it.  The pellicle is filled with massive loads of bacteria and yeast, and it plays an important role in protecting and supporting the growth of the new bacteria and yeast that form during fermentation.  Without it, the microorganisms may be more susceptible to external threats and may not grow as well.  Additionally, the pellicle helps to support the exchange of gases and nutrients between the microorganisms and the fermentation medium, which is essential for the production of kombucha.  Without including the pellicle from your previous batch, it may be more difficult to achieve the desired fermentation and produce high-quality kombucha.

So do you really need to include a pellicle when making a new brew?  In short, yes!!!  If you were building a new body for yourself, you’d never leave out a piece of the immune system right?  So why would you ever do that with your kombucha?  While it is possible to brew kombucha without the pellicle from a previous batch, it’s not a very smart thing to do.  Including the pellicle (because of the super high numbers of bacteria/yeast and its function as a brew immunity supercharger) greatly increases fermentation success rates and greatly decreases the possibility for contamination — this are concepts nearly universally agreed on by commercial kombucha brewers around the world.

Should a pellicle sink or should it float?

Pellicles from previous batches may sink or swim throughout fermentation – both are totally normal — and whether they sink or swim has absolutely no bearing on the health and activity level of your brew.

Of course your new pellicles will form on the top of your brew, but it’s not uncommon for those to drop during fermentation too – usually due to your brew being moved or agitated in some fashion.  As it relates to your ferments, remember that the pellicle is full of huge numbers of bacteria and yeast that your brew needs to thrive, so always include your newest one when starting a new batch.  Older  pellicles can be reused multiple times, but they’re not as effective as newer ones, so usually they’re tossed or composted if you don’t have an additional use for them.  If you’d like to learn more about what you can do with leftover pellicles, checkout our Uses For Leftover Pellicles post.

Where does it come from?

It’s believed that fermenting tea with a scoby began thousands of years ago in Eastern Europe or Asia, with the first record in 221 BC from Emperor Qin She Huang and his ancient recipe for the “tea of immortality.”  But booch has been mentioned in folklore all over the world.  In Russia, mythology suggests a mystical monk healed a dying king with tea that forms “a jellyfish” when ready. It’s also said a Tibetan monk found something forming in a forgotten pot of tea, which other monks drank for its health benefits (the tea had transformed into kombucha).  And what do we think here at RBC? Glad you asked. Well there certainly wasn’t processed sugar around thousands of years ago, and raw honey has many of the yeast and bacterial building blocks for a SCOBY.  So, it’s our belief kombucha probably started as an accident, independently in many cultures through tea, honey, and citrus (for acidity).  

Properly brewed kombucha will always produce a new scoby.  The mother scoby (technically the bacteria and yeast working together to make cellulose, proteins, and polymers) will “birth” another on top of your ferment, which will then continue the chain of reproduction.  And once you begin making kombucha on the regular, you will have an endless supply. You know you’re doing things right if you have a whole scoby daycare on your hands.  That’s why it’s important to know how to ensure its survival — think of your scoby as your new indoor plant. 

Have the correct storage. This means out of the sun in a jar that won’t inhibit its growth, and you must feed your brew sweet tea.  Keep up with your brew cycles, and be careful to not disturb your ferment with too much movement. (See: Scoby Care & Hotels for long term storage and care guidance) When you do need to handle your scoby, a pair of clean metal (or hard plastic) tongs is always preferred to clean hands.  Some people think it’s okay to use your hands, and don’t have issues — but we suggest against it.  No matter how clean you believe your hands to be, unless you’re a surgeon headed into the operating room, freshly washed tongs are nearly always cleaner. 

Scoby Myths

There are some misconceptions surrounding this pancake of bacteria and yeast. The first myth is this: a scoby is NOT a mushroom.  Though it may be nicknamed “the mushroom,” it does not make Momma a fungus.  That being said, it is formed in part by fungus — because yeast is a fungus!  

Scobys are recognized as “zooglea,” which is essentially a living skin that is a gelatinous concentration of bacteria and yeast.  And scobys can ferment both anaerobically (without oxygen) and aerobically (with oxygen) — but a kombucha scoby prefers a steady supply of fresh oxygen so it can ferment quicker and more completely.  As far as we (and all other commercial brewers) are concerned, oxygen is necessary. When your booch is fermenting, cover it with a coffee filter or another breathable fabric with small enough pores to keep out dust and fruit flies.  Never use muslin or cheesecloth as a cover, as the pores are simply too large, and greatly increase the potential for contamination. 

The second myth is that working with a scoby to make Kombucha is not safe to do at home.  That’s just crazy talk.  Making kombucha at home is ridiculously easy with the RBC system — and extremely safe.  The correct pH for your kombucha is an acidity level that most bad bacteria can’t thrive in.  Mold can happen (see this article for how and why mold can happen), and if it does, then it’s time to throw that batch away and start over with a new scoby.  Do not use a moldy scoby or drink the kombucha it produced — it probably won’t hurt you, but it also won’t taste very good.  Identifying mold on a scoby is pretty easy, but when you’re a new brewer you might not know what to look for.  View our Is It Mold page if you aren’t sure.  You can always post a photo there for our review as well. 

Great kombucha comes from knowing your brew, loving your brew, and taking care of your scoby.  So, if you want to give your scoby and your booch game the kind of lovin’ it needs, consider exploring our other Raw University articles here. #welikeitraw #rbc #kombucha #scoby

Sources

“Fermentation.” Encyclopædia Britannica. Encyclopædia Britannica, inc. Accessed October 15, 2020. https://www.britannica.com/science/fermentation.

Jayabalan, Rasu, Radomir V. Malbaša, Eva S. Lončar, Jasmina S. Vitas, and Muthuswamy Sathishkumar. “A Review on Kombucha Tea-Microbiology, Composition, Fermentation, Beneficial Effects, Toxicity, and Tea Fungus.” Wiley Online Library. John Wiley & Sons, Ltd, June 21, 2014. https://onlinelibrary.wiley.com/doi/full/10.1111/1541-4337.12073.

Troitino, Christina. “Kombucha 101: Demystifying The Past, Present And Future Of The Fermented Tea Drink.” Forbes. Forbes Magazine, February 17, 2017. https://www.forbes.com/sites/christinatroitino/2017/02/01/kombucha-101-demystifying-the-past-present-and-future-of-the-fermented-tea-drink/

Wolfe, Benjamin. “Microbial Diversity of Kombucha.” MicrobialFoods.org, September 27, 2015. http://microbialfoods.org/science-digested-microbial-diversity-kombucha/.