The Diary of a Winemaker - Picking, Sorting and Fermentation

David Thomas

28 September 2020

Welcome to the second part of our blog series featuring our Sales Director, David Thomas, following his adventures at Le Pin day by day through the wine making process.

Over the last couple of weeks David has been getting his hands dirty (quite literally!) helping out with this year's harvest. With years of experience under his belt, David knows the ins and outs of the winemaking process. This blog is going to shed some light on the intricate wine-making process at Château Le Pin, delving into the detail of the first couple of days of fermentation and the impact of the scorching early September temperatures. Discover what it is that makes Le Pin wines ultra-collectible and ultra-expensive. From sorting and picking the grapes to the primary ferment and remontage process, uncover the juicy details of the first stages of wine making at Le Pin. Hear about David's first couple of weeks in the spectacular wine appellation, Pomerol.

Diary of a Winemaker
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As I pulled up to Le Pin around 2 weeks ago – Sunday 13th September - it was close to 36 degrees and the weather was insanely hot. Looking at the vines while travelling through Pomerol it was very clear that the lack of rain and intense temperatures had started to impact on the growing season – the vines were looking exhausted. Looking around the vineyards as I arrived at Le Pin it was clear that they were most definitely in need of some rain! Leaves were shrivelling and many had fallen much earlier than normal, exposing the fruit to the intense sun which is never the perfect environment for the optimum vintage. The continued heatwave of course impacts the harvest... as the vines begin to feel the impact of the drought and excessive temperatures, they tend to start to shut down; the rate of photosynthesis drops as the plant tries to protect itself and although the sugar levels in the berries will continue to increase whilst acidity levels fall, the grapes are not phenologically ripe. When tasting these berries, while they are sweet they lack depth and complexity, and the tannins are often under-ripe. The resulting wines can be out of balance with a high level of alcohol, lacking in acidity and freshness and often have a hollow mid-palate. It is not a pleasant game to play thinking that an entire year's labour and dedication in the vineyard could potentially be, and please excuse the pun, fruitless. So it is all about the finesse and expertise of Jacques Thienpont and his team to manage the harvest and wine making process to nurture and extract the potential from the vintage.

Picking and Sorting

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One of the key decisions of any vineyard manager or wine maker is choosing the picking dates – and who would dare to predict future weather conditions? This is the common dilemma - do you wait for rain and risk leaving the vines in the heat or start picking and not risk the wait? Most wineries start by picking the younger vines first as they do not have the established root systems that the older vines benefit from. The older vines can withstand the lack of water for longer periods thanks to their deep roots. This is exactly what we did here at Le Pin: we started picking the younger vines on the 14th September. The picking date is carefully selected by tasting the grapes - there needs to be sweetness and acidity present but what they are really assessing is the phenolic ripeness of the fruit. Once this has reached a sufficient stage then the picking can commence.The picking team are watched over carefully by owner Jacques, Alexandre and Guillaume Thienpont; they're a trusted and skilled team who become part of the family during the picking season, as the same team is used both for Le Pin and neighbouring vineyard Vieux-Château-Certan (VCC).

As a point of interest, both La Conseillante and Figeac started picking their young vine Merlot on the 4th September – 10 days before Le Pin and VCC – which shows not only how different and varied the terroir and micro-climates are in Pomerol and St Emilion, but also the different thoughts and choices on picking days. I will come back to both Châteaux in later blogs as I have been dropping in from time to time over the vintage to see how the harvest has been progressing.

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Once the picking commences there is a detailed production process that is put in place. A sorting table is established in the vineyard, and given the continuing heat this was set up undercover to provide a bit of respite from the blistering sun. The grapes are emptied onto a conveyor belt where they are then sorted by hand. This laborious process is imperative for the elegance, finesse and quality of wine produced at Le Pin. Grapes will be removed that have any imperfections such as sunburn, rot or uneven ripening. Once the first stages of sorting are complete, the grapes are then couriered by tractor the short 200 feet to the winery. The bunches are then immediately de-stemmed, crushed and pumped straight into one of the various sized vats for fermentation at Le Pin. The whole process from the sorting table to the grapes being pumped into the vat takes less than an hour. The grapes do not spend a second waiting around!


Diary of a Winemaker
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Once the picking, sorting and crushing are complete and the berries are in the fermentation vats, the next stage of the wine-making process is the primary ferment. The vineyard is split into blocks and one of the beauties of Le Pin and part of the reason that the wine is so exclusive is that Jacques Thienpont has the ability to keep each of the blocks separate throughout the fermentation process. Jacques has a number of vats in a variety of sizes at his winery and depending on the yield of each block, they will go into their own vat of an appropriate size to ferment individually. This gives the opportunity post fermentation for Jacques and his team to blend the juices from each vat to create the desired wine. Think of it like a painter with his colour palette, the artist will choose varying amounts of each colour to create the precise shade and colour needed for his painting. It is exactly the same at Château Le Pin, Jacques will use varying amounts of liquid from each vat/block, creating the optimal combination and ultimately, the perfect wine.

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The reason there is not one uniform size of tank is because the yields from each block will differ. It is important that the tank is full when the grapes and juice are pumped in or there will be negative impacts. A half empty tank has a much greater air gap at the top which leads to increased oxidation. Throughout the harvest, there are times when the grapes arrive and are pumped in, only for us to realise that we have less fruit than expected. It is then a matter of us jumping into the tank - yes I mean literally… shoes off and jumping feet first into the vat of wine! Time is of the essence here because fresh 'must'(grape and juice mix) is prone to oxidation so it is important to move the mixture quickly. Whilst time is pressured, it is important to transfer the grapes very carefully again to prevent oxidation. To do this, we use a bucket to move the juice to a smaller tank, reducing the impact on the grapes. I am pleased to say this has only happened once so far! As you can see, immense care is taken to prevent any excessive oxidation at this point, this is because oxidation flattens the flavours and aromas of wine.

Waste and water

Another very important point to note throughout the wine making process is that every drop of liquid is sacred. A lesson I learnt almost instantly 3 years ago during the 2018 vintage when a small drop hit the floor and Jacques immediately commented, “that will come out of the Bordeaux Index allocation”, I have soon come to realise this is one of his favourite phrases! With Le Pin only making 700 cases of wine a year and boasting some of the most expensive wine on the market, it's no surprise Jacques does not want a single drop to go to waste. The other important point to make is just how important cleaning the winery regularly is. It takes so much water to make wine and maintain pristine working conditions: every time we take a sample, use a tap, finish a remontage or spot any sign of grapes, skins, juice, fermenting juice or wine outside of the tanks – it's a hose or sponge out.

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Temperature is also vital when processing the grapes, given the temperatures were still in the mid-30's when we were picking, so the grapes / juice arrived at the winery far too hot and so once in the tank, CO2 was pumped over the fruit again to prevent oxidation. The cooling systems were also turned up as ideally we would like to bring the temperature of the grapes and juice down to around 14 degrees prior to allowing the fermentation to start. In essence you want the fermentation to take time, and the hotter the ferment the quicker the conversion of the sugars to alcohol and the faster the fermentation is completed. An easy way to explain this is, it is like cooking a spaghetti bolognaise – if you cook it in 20 mins it will look OK but taste terrible – but if you let it slowly cook over many hours, well that's a different beast indeed and it is exactly the same with fermentations. The optimum conditions for fermentation differs from winery to winery and indeed vat to vat, in general if the fermentation takes anything over a week and hits a maximum of 30 degrees during the peak of fermentation then you're heading in the right direction. You don't want the temperatures getting too high as hot ferments can destroy primary fruit characters, over-extract harsh tannins and reduce acidity leading to unbalanced and often 'thin' wines. It is a skilled balancing act...

Remontage 'Pumping Over'

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The 'must' (now slightly crushed grapes and juice mix) is allowed to rest for a few hours as the temperature is reduced before the very first remontage. The remontage process is also known as 'pumping over' – taking the liquid juice from the bottom of the tank and pumping it back over the layer of floating skins on the top of the tank. This initial pump-over has two purposes: firstly to mix the tank to allow for a more homogenous sample to be taken. In which the specific gravity (sugar levels) which indicate the potential alcohol levels, levels of acidity and temperature of the tank will be measured. Secondly, it starts the process of extracting colour, tannin and flavour from the skins of the grapes. Given the excessive heat of the 2020 ripening period, it has resulted in some fragile skins which means that in this vintage we have to be super delicate when pumping the juice back onto the skins. The ratio of juice within the berries to skins is very low in this vintage, making extremely concentrated juice and it also introduces the problem of over extraction – more on this to follow in my next blog. Everything is done extremely delicately and the average length of the pump-overs will be lower this year than in either 2018 or 2019 as the more you macerate the skins, the more tannins you will extract. The skins are very delicate this year due to the harvest and so the tannins will be extracted much more quickly, it is very important to get the balance right. You don't want to under extract or the wine becomes too thin, over-extract and the wines become harsh and the result is bitter tannins rather than sweet. But as I mentioned, more on this to follow. One thing I can say is that the colour was looking amazing within the first 24 hours and the aromas wonderfully pure – ripe, yes, but pure!!

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Moving on to Yeasts

There are many people who harp on about natural / indigenous yeasts for fermentations. I would challenge anyone to blind taste wines and tell me if the yeasts used for the fermentation were natural or selected.

It has become a romantic fairy tale to use indigenous yeast. It is a massive risk, especially in hot vintages, and can ultimately ruin the entire tank. Allowing a 'population of yeasts' to dominate the fermentation in a controlled and safe way is the norm around the world (trust me the last thing you want is a stuck fermentation) Let me explain, this is where the initial population of yeasts fails to complete the conversion of sugars into alcohol and you risk the build-up of acetic acid within the winery... you might as well start off bottling it as red-wine vinegar as it can turn very quickly indeed. We have used a completely neutral but wonderfully stable and reliable yeast at Le Pin this year – you could, if you wanted, phone up a company in Switzerland and ask for a yeast that adds cassis flavours to your ferment if you so desired, but it is certainly not required here! The cooling system is momentarily paused to allow the yeasts to start working their magic – they produce heat while converting the sugars into alcohol. You allow the temperature to increase to somewhere in the mid-20's initially and once this heat has been reached then the cooling will restart again mid-ferment.

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The real fun starts now – with more grapes to pick over the coming days and daily remontage – hands are becoming stained and the aromas that build in the winery are intoxicating.. the end of the first day was celebrated with a relaxed dinner with Jacques and Fiona. Of course, enjoyed with a bottle of wine or two to discuss the coming days of harvesting and the timetable of work at Le Pin, L'If and the newest property L'Hetre... keep your eye on our blog for details on the bustling harvest and exciting new ventures.

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