Hello everybody, welcome to the Wine With Jimmy channel. I hope you are all very much tickety-boo and doing well. So welcome to the channel about wine education.
So here at Wine With Jimmy we deal with helping students... really learn and feel confident around topics of the WSET level 3 and level 4 specifically. Now in this series we are looking at something called explaining wine terminology.
So from time to time I release a video which students often ask me to really explain in greater detail because they find it potentially a little bit more challenging to understand it. So here we will be looking at the process of semi-carbonic maceration, something which definitely could be a part of your level three examinations when specifically you're looking at Beaujolais or at your wine production section of the WSET level four diploma. Now if you do have any comments or questions or concerns you can get in touch with me here at Wine with Jimmy by the social media that you see at the bottom of every slide or because this is available on the channel here.
at Wine with Jimmy on YouTube you can actually comment below me please make sure that you click the subscribe button as well to get all of our weekly updates on wine study materials so also you can go across to winewithjimmy.com which is my wine educational portal where you can find and subscribe to the wonderful area which gives you lots of access to things like multiple multiple choice questions, short written answer questions, revision sessions, flashcards and of course exclusive video content to help you with your studies. Okay, so let's begin talking about semi-carbonic maceration. So this process will fall under the category of whole berry or bunch fermentations.
It is the most common of the whole berry or bunch fermentations. So I'll focus here exclusively in this presentation just on semi-carbonic. Of course, there are others as well, such as carbonic maceration, but here we're just talking about semi-carbonic. Now, it's called semi-carbonic maceration because really it is a part carbon dioxide maceration and then a part yeast fermented driven style.
So it's a bit of both, so that's why we call it semi. The carbonic part of it is because carbon dioxide used to be called carbonic air and that's where the carbonic section comes from. So let's talk a little bit here about actually to begin with what kind of grapes we need then we'll get into the aims and then eventually we'll get into things like the process step by step.
So first of all winemakers can either choose to use whole bunches of grapes or whole destemmed grapes of course when thinking about wine production and also to use either entirely uncrushed fruit or just a small proportion of in within a crushed fruit fermentation if whole bunches are used the grapes must therefore if they are used for fermentation must be hand harvested they'll need to be intact with their stems as they come into the winery if whole bunches of grapes are used it's also very important that the stems of the bunches are fully ripe. Stems could add flavours and sometimes you might actually see wines having a spiciness or a herbal element due to the stem inclusion. However, unripe stems can actually add unpleasant green flavours, astringency and bitterness in the final.
wine style. So if we are hand harvesting and using with stems we will need them to be ripe enough for the processes that we'll go through. Okay so next up then what is the aim of the process of a whole berry or bunch fermentation? So notice here we're still talking about whole berry or bunch fermentations.
I will start to go to semi-carbonic very soon but I'm just giving you an overview. of the processes at this point. Now the objective of a whole berry or bunch fermentation is to create an oxygen-free environment for the uncrushed fruit. So that's why here you'll see that oxygen has a big line through it on your slide.
This lack of oxygen has many outcomes. The grapes will change from aerobic... respiration to anaerobic metabolism. OK, in the anaerobic process, some of the sugar in the grapes can be converted to alcohol.
And this occurs without the involvement of any yeast. And this is referred to as intracellular fermentation. OK, so that is the process of producing some alcohol, but without the yeast component to it.
How does this happen? Well, we're going to talk a little bit here about. the role of malic acid and the role of glycerol in this style.
So malic acid within the grape is broken down to create ethanol. This can reduce the malic acid levels up to around 50 percent, 5-0, 50 percent, lowering, of course, the total acidity and raising the pH of the must or the wine. So. this is what we're showing you here. So malic acid is being reduced on the left hand side, the pH is being increased and the ethanol, a small amount of ethanol is produced at this time.
Also, glycerol levels will increase. We talked about the role of glycerol in wine components and we talked quite a bit about the fact that glycerol is more common in things like sweet wines where you have botrytis, but also there is some produced via this process, by this method. and that can add texture and a range of distinctive aromas are also produced as well and they're classically things like kirsch and banana and bubble gum and we'll look at those a little bit later okay now let's go through just a slide here on the historical stance of semi-carbonic maceration and then some sort of form of economical factors as well so it is likely that semi-carbonic maceration happened accidentally when a winemaker left their grapes unattended for too long in a closed environment, a closed container of some description. So this of course will create the environment that we're about to go through that we need for this process to occur. Semi-carbonic is likely to have happened first and therefore is the oldest technique of whole berry or bunch fermentations.
It's used to produce very young, fresh and fruit forward styles which are very much readily drunk and very much drunk in an early stage of their life. They also can be chilled and specifically a lot of these wines are made in quite warm areas, moderate warm or even hot areas. So the fact that you make a very fresh fruity red which could be chilled suits the locality so it really suits the domestic market certainly in those summer months it is also in terms of an economical stance a very quick style to produce and often many of the examples are released within the same year as the harvest and this is really the economical angle here because the wines can be released before other wines and of course produces a good constant cash flow for the winery that is attempting these styles. So of course if you look at Beaujolais Nouveau in the Beaujolais region in sort of central south France then these Beaujolais Nouveaus are released at the end of November, the third Thursday of November and that's before the year before really the other wines may be released such as the Village wines for example and that means of course there's good cash flow coming into that winery immediately after harvest. and going into the next year as well.
Okay, so there is certainly an economical angle, certainly where the countries produce this style. So let's go through the process now, which of course many of you are very excited to understand because it is something that certainly WSET has a propensity to ask questions about, certainly when, of course, we're looking at, say, Beaujolais as a question. So first of all then we'll see here we've got a vat on the left hand side and currently this vat is open.
OK, now whole bunches of grapes, which, of course, have just been hand harvested, will be placed into this vat. So this will be immediately after the hand harvest. Now, there'll be no pressing, no crushing or de-stemming. They are intact whole bunches at this point.
Now, of course, they are in a container and there's going to be some pressure created at the bottom of that vat due to the weight of the grape. within that vat and that pressure will cause the grapes and the clusters at the bottom of that vat to start to burst. So that's what we've identified for you on the left hand side. The grapes will begin to burst and you can quite clearly see it in the graphic there as well.
Okay so what's the next step? So the ambient yeast or the wild yeast that we find on the skins of the grapes will transform the natural grape sugars which have been released due to them being crushed. They will be converted into a bit of alcohol at the bottom of the tank. During fermentation, of course, carbon dioxide is produced and that is then released and it forces out the oxygen. That's what I am attempting to show you on the left hand side in the diagram again.
So carbon dioxide is produced and the oxygen is released. which is there, is forced out. And that's really because carbon dioxide is heavier and denser than oxygen.
And that creates an anaerobic environment free of oxygen, full of carbon dioxide. Now yeast, of course, when it starts to ferment, will need oxygen for the traditional alcoholic fermentation. Of course, it no longer has that. So it is not. possible to continue the fermentation under those conditions.
So the fat will be very quickly sealed around that point and in essence the grapes begin to absorb the carbon dioxide and the anaerobic environment encourages a carbonic maceration or this is what we can call an enzymatic or biochemical fermentation and that's inside each of the intact elements. berries. Really the grapes in essence begin to eat themselves, their enzymes begin to eat themselves as they have no living environment, no living oxygen.
So during this biochemical fermentation a small proportion, that's around 2 to 2.5 percent alcohol, is produced from the malic acid. So that malic acid is converted to ethanol and that's what we are showing you at the bottom of that diagram again. And that's through the enzymes.
And this is really where the foundation box for those compounds in classic semi-carbonic macerated wines are produced, those kind of Kirschy bubblegummi characteristics. The pigment and the tannin is absorbed at this moment by the pulp because, in essence, those berries are bursting. So the tannin and the colour, the pigmentation, or what we call the anthocyanin.
is absorbed by the pulp, making it a very pinkish purple colour. But really, it's the colour which is absorbed here. Tannin is very minor, very little tannin. And that's really due to the environment not being anywhere near as warm as a normal fermentation would be. So there's very little extraction of tannin.
But good colour will come through. Not a dense colour, but that kind of pinkish purplish colour, which is quite typically associated with these kind of styles. In essence, the berries have died at that point and the process will begin to shut down at that point.
OK, so what about what happens now then? Because we haven't produced a huge amount of alcohol. It's around two to two point five percent at that point.
OK, so what do we do? So the free run juice is drained off at around two to two point five percent alcohol. And of course, that's not high enough.
There's a small proponent of alcohol at that point. And there's some or a lot of juice at that point. So that will be drained off and that will require yeast. to be added to it to ferment it to bring it up to normal wine alcohol levels. So yes, you've drained off the juice.
So what's left in that vat is a pulp of skins and stems and all those kind of things with some juice again. The remaining grapes will be pressed. So the remaining grapes will be pressed to obtain press wine.
They can be pressed at a number of different days after. So you could find that they may be pressed only one, two or three days after contact with the skins. And that's very common for most generic Beaujolais or Beaujolais Nouveau, for instance.
If it's a little bit more, like maybe five to nine days before being pressed, that's often for things like Beaujolais Village. And then maybe somewhere around sort of eight or nine to 15 days contact with the skins and then pressed. That will be for the cruise, as you will expect.
More of that contact as you go down that list, as I've just gone through, will mean that you will have greater extraction in that pressed wine of colour and of tannic structure as well. OK, now, during enzymatic fermentation, the grape berries will actually. burst as we mentioned and that will release that bit of juice into the vat.
That juice will need to go under a yeast driven fermentation as well and basically what happens is of course you will then blend into the the press wine will be blended into the free run wine. Those two components are blended together. Another reason why you would call this a semi-carbonic maceration because you have partially free run.
And that is what has gone through quite a bit of a yeast fermentation. And then the enzymatic biochemical section of that, which is the press juice, the press wine, which is finally produced. OK, so that is your process there.
Please remember that the more skin contact with the press element is what will be really given to things like village level and crew wines. So what is the resultant style then? Well, resultant style in terms of characteristics is certainly low tannin.
So we find low tannins, we find good acidities, but some of those have been reduced, certainly the malic, through the process. And we'll find some nice bright colours, but not necessarily deep. But that will really depend on the amount of skin contact in terms of the press wine element of the style.
We also find very fresh fruit flavours, typically things like strawberries and raspberries and cherries, which are all identified there on your slide. Very classically, one is called ethylcinnamate, which is that very strawberry element in the style. But also the cherry can be a bit more kershey, and that's what you've got in the picture there.
Things like banana produced as well. So these quite interesting ester compounds, and then things like bubble gum or candied sweets as well are produced via this process. Where in the world do we find this production?
Well it results in wines as we mentioned with fruitiness and with a softer mouthfeel than normal crushed fruit fermentations and it's used for varieties like Pinot Noir, Malbec Tempranillo, Gamay, Carignan, plus many others. Now in terms of where in the world, of course, Bourgogne, sort of general level, generic Burgundy, will potentially have semi-carbonic macerated fruit for Pinot Noir. Certainly things like Passé Tucran as well in Burgundy.
Beaujolais, of course, is really the hot spot for it. It's the classic area for semi-carbonic maceration across. most of the styles from really the sort of generic Beaujolais and Beaujolais Nouveau and even up to Cruz. Not all of them of course but it can be that way.
The south of France certainly in the Languedoc you'll find a lot of Carignan which is made as a semi-carbonic method and in La Rioja in northern Spain specifically areas around the Alavesa which is your Basque part of Rioja. you will find that there are semi-carbonic styles also made here it's quite a traditional style actually by some some winemakers and that's it's kind of making a comeback with younger winemakers too to produce these real bright fruity expressions which can be a counterpoint to the really complex and tertiary-led reservers and grand reservers so that is in La Rioja and of course this is just Europe but of course it's been adopted around the world you will find producers in places like South Africa Australia and others around the world are adopting the semi-carbonic macerated method. So I hope you have found this video on wine terminology useful to help you with either your WSET level 3 or level 4 studies. As always if you do have any comments, questions or concerns you can get in touch with us. You can do that via the comment section below this video on YouTube.
or by the social media that you see at the bottom of every slide, or direct at www.winewithjimmy.com as you'll see here on this slide where you'll find my very useful e-learning portal. There is a snapshot of what you may find if you register as a student for the e-learning portal. This student here has actually registered for the level one, two, three and level four stuff which I don't think you'll be doing. if you're watching this video but maybe you would like to register for maybe the level three and level four where you'll find exclusive video content huge amount of study aids such as flash cards revision sessions short written answers and multiple choice so they're all found there but really the exclusive video content is very very useful the level three for example we have over 110 videos on there and that is counting from may 2021 and that's always being added to every week and the diploma also has lots and lots of video content well if you do find yourself in the wonderful united kingdom and in old blighty here in london then come and see me you know i've got schools and bars so come and see us for a class a glass or a bottle i've been jimmy smith and see you very very soon goodbye