18 months ago I grabbed a whole load of common/Persian/English walnut leaves to make a walnut leaf wine. Having made an oakleaf wine I knew the basic flavour profile that would emerge and was interested to see the results from walnut leaf.
Oak leaf creates a decently complex sherry like wine that is great chilled to highlight the absolute dryness it creates with its tannic base. While having an initial pine like hit then warming depth it is clean and clear like a mountain stream… made of oak leaves.
Walnut leaf shares the same base of tannic dryness but has a roundness that lacks an expected nutty base or the sharpness of oak leaves. There is the herbal tone with an oddly citrus note that is not lemony or acidic but an earthier pomelo and melon feel. While walnut cannot be chugged down as a dry white it very much can be enjoyed as a more relaxed long lasting ice cold digestif. The flavours worked best when it was cold. The depth also hints at the possibility to age far longer and also use as a base for cocktails.
Tannin I think is often misunderstood in fruit wines. Feared even. It is often talked of in terms of minimising tannin levels as if it should be totally removed from wine and wine making altogether. Often tannin it is actually added either as a pure additive, as tea or in oak chips when it is ageing. Oak chips provide “hydrolyzable tannins” that provide greater mouth feel with a softer taste to the harsher “condensed tannins” that are present in fruit juice in low quantities and more prevalent in some fruit skins, seeds and stems.
Both red and white grape wines have tannin present but it is far more prevalent in reds as it macerates on the fruit for longer. Little tannin is extracted aqueously but as the ethanol level rises so too does the extraction of tannin. Grape wines are the basis of fruit wines as the taste template we use as a reference. Home wine makers are beholden to those norms. Sadly not all fruit has the same characteristics of grapes so adding or managing tannin becomes important to replicate the balance between sweet, acidic sour and bitter tannin tastes of grape wines.
White fruit wine ingredients vary in tannin content. Elderflowers for example need tea added as the petals are naturally low in tannin. Gooseberries – the “hairy grape” has tannin present in the pips and skins so does not need any additives and I have found that pressing after an initial short maceration helps manage the tannin content to match that of a traditional white or rose wine. This is done two days into fermentation when the solids are removed, pressed then tossed away and the remaining wine happily sits in primary fermentation for a few days more.
Red fruit wines have more variance in finished tannin content due to personal preferences in taste and style as well as the initial tannin content of the fruit that makes them. Some people may want a full bodied tannic blackberry wine, a medium bodied blackcurrant or perhaps a light bodied almost rose elderberry wine made from a second run fermentation. The tannin levels vary between the base fruit but it can be managed to make the style of wine you want. Because of this tannin becomes far more about management than simply addition or removal as with a white wine.
Always plan ahead and have an idea of the wine you wish to make. Generally it is thought that high tannin content and low tasting acidity and higher alcohol content work with each other as a flavour profile. This means that an idea of the final ABV and initial sugar content derived from a hydrometer reading is useful. Fresher tasting younger style wines will need less tannin, but if you have a preference for full bodied wines, with both time and will power to age your wine more tannin can be present.
I can think of few fruit wines other than oak or walnut leaf wine and possibly some dandelion wines that use stems. Stems should always be removed from fruit as they are high in harsh tannins. This is especially so in something like elderberry or elderflower wine as the stems are toxic as well as tannic! A good eyeball and preparation of fruit will help you make a good wine.
After a style is in mind a recipe needs to match it. Blackberries have some tannin present in them and are a good example where the recipe can change the style of a wine. The berries left to themselves will create a traditional medium-bodied wine that could be drunk at nine months in age if you are very very lucky. Blackberries with a tea added will make a fuller bodied wine that will need 18 months ageing before it approaches drinkability.
Elderberries have the opposite problem and as they have a high proportion of thick skins and seeds compared to the juice they provide when crushed or pressed. When processing tannin rich fruit it is important not to break the seeds or pips as the interior has the harshest tasting tannins that could ruin a wine if extracted in large quantities. Blending in a foot processor or an extremely thorough press could crack the seeds and release it. There are several methods to control the amount of tannin extracted. Cold maceration allows an aqueous extraction of the least harsh tannins from the skins before the berries are crushed. In conjunction with removal of the fruit mid way through primary fermentation less tannin will be extracted. Pressing the fruit pre-fermentation then discarding half the skins and allowing those remaining to sit for the duration of primary fermentation could also work. This will allow the extraction of different tannins as the seeds will be exposed for far longer.
Alternatively whole elderberries could be left to ferment with months in bulk ageing to allow the tannins combine and fall out of suspension as sediment that is left behind when racking. This very much leaves it to chance. In addition or an alternative certain settling agents like gelatine or isinglass can be added to remove tannin when racked. It should be noted that tannin can also act as a natural settling agent combining with certain proteins as it ages and settling agents could interfere. Mechanical filtration though filter pads is a final way to remove tannin but that can also remove other flavour compounds… apparently… the jury is still out on that discussion.
Oaking a wine occurs neer the end of bulk aging just before bottling. This replicates the aging process in a wine barrel. Few white wines are aged in oak barrels but it is not unheard of and I may try it with my elderflower wine next year to simulate a Chardonnay style. Whites are generally unsuited to oaking with chips as the higher acidity (lower pH) conflicts with the tannin tastes. Typically less than 10g per litre of oak chips are added to either white or red wines and they can sit for a few days to three months extracting the oak flavour. A home made port is an exception as it is so rich and more than likely sweet it can with stand the high tannin extraction, ranging from 20 to 30g of oak chips added per gallon and resting for up to three months or more. Oak is not a tannin addition like tea and is not meant to provide the whole tannin content, merely to compliment it with a range of usually lighter tannins to add complexity as top notes. All oaked wines will need longer to age than an un-oaked wine of the same recipe as the tannin will gradually bind over time to create a rounded mouth feel and balanced taste.
English walnuts can be be added to the list of English things that are not English just like tea, fish & chips and the royal family. English walnuts – Juglens Regia are probably from Persia, adopted by the Greeks then Romans and can be found all over the world including England.
Iran is not that big on wine making but there are various uses of green walnuts in liqueurs like Italian Nocino or Orahovac from Croatia with almost every European country having a variant on it. The French make Vin De Noix again with green walnuts but in red wine rather than a spirit base. Mature walnuts can be used for amaretto/frangellico like liqueurs. There are several black walnut bitters from America to add a deep smokey tobacco-esque taste to cocktails and finally the leaves can be used to make wine. Walnut trees really do seem to be the unsung hero of DIY drinkers.
Many leaves can be used to make wine with oak, grape, bramble, maple, beech, lime or birch. Walnut leaf and particularly black walnut leaf wine are meant to be the best of the lot and I have been wanting to make it for a while. Finding walnut trees is tricky in Britain – English walnut trees are rare and American/black walnut trees (Juglens Nigra) even more so. Around Vintner HQ there happened to be a tree that was sadly next to Walthamstow’s busiest road. I don’t really want to make walnut & diesel soot wine. As if to rub it in there was a tree on common land that was too small to harvest leaves from. I want 6 bottles of wine but do not want to kill a tree in the process. Then there was a black walnut tree in a park so off limits… Mother Nature seems to be bit of a tease it seems. It has taken over a year to track down trees that are both suitable and possible to forage. Sadly these are just English walnut trees… but they are walnut trees!
Walnut trees are wide stocky lads with stout trunks and large canopies. Early in the year there have distinctive catkins and small walnuts start to form in late May. The leaves are pinnate with Ameican and English trees having slight variation in size and shape but they both have a very distinct scent. Rub the young leaves and they will smell like a lime flavoured nail polish… mmmmm!
These pungent leaves are far stronger than others that make wine. Oak leaf wine needs 3 to 4.5 litres of leaves picked to make 4.5 litres of wine, walnut only needs a fraction of that at ¾litre so picking is far easier. There are spring and more tannic autumn harvested oak leaf wines but walnut leaves should be harvested only when they are young and fragrant in May or June. The recipe is essentially the same with oranges and lemons adding some acid with their juice and also flavour with the zest. I have chosen to use raisins to add body though some prefer to leave this out for a more esoteric brew suited as an aperitif, while others use white grape concentrate or even a malt extract. If you do want the more aperitif like wine use light brown demerara sugar instead of regular white sugar to the same amount.
Spring time oak leaf wine is herbal and light but with the young walnut must there is currently a smooth caramel like taste that is certainly richer. I am hoping the walnut leaf will be a stronger with a warmer nuttier taste coming through. Using my oak leaf wine as a guide I will need to let this mature for at least 18 months or possibly even two years. Six months from now I will have four bottles sealed and aging and the remaining 1.5 litres will sit in a small demijohn to oxidise. The idea is that this will make a fino like sherry as they often have nuttier tastes – there is no way I am investing in any flor yeast or moving to Jerez so lets agree to call it a Faux-no.
Before you start cover every surface that might come into contact with the leaves. Walnuts stain and were a traditional source of dyes and the leaves have the potential to stain wood and clothing.
WALNUT LEAF WINE – 4.5 litres
Suitable yeasts – white wine like CL23, SN9 and others
Up to 1L freshly picked walnut leaves
1kg-ish sugar to 1.09SG
Juice of 4 oranges and zest of 2
Juice of 2 lemons and zest
Pick and then rinse the leave to remove any hitch hiking spiders. Pour over the 3.5L of boiling water and leave for 24 hours. Any longer than one day soaking will release far too much bitter tannin that will dominate.
As the leaves steep boil the roughly chopped raisins and lemon and orange zest in the remaining litre of water.
Sieve the leaves out of the water once the 24 hours has elapsed and combine with the raisins and zest. Add the sugar, lemon & orange juice and stir till the sugar has dissolved.
Add the yeast & nutrient according to its instructions. Leave to ferment in primary and then transfer to an air locked demijohn when fermentation slows after five to 10 days leaving the raisins and zests behind.
Rack if sediment builds and certainly at one then two months to remove the settled yeast.
Leave to bulk age in a demijohn for as long as you can – six months at least.
Bottle and open a minimum 18 months after starting.