March 3, 2020

Every fall I make Sauvignon Blanc wine or, as this past winemaking season, Chenin Blanc from Mosti Mondiale must. The wines have always been exquisite.

And now I finally gave in to the itch of trying one of their high-end wine kits.

So I got a Limited Edition Meglioli Riesling kit with 100% grape must, i.e. no water to be added, from fruit sourced in 2019 from the Finger Lakes region in New York state, and more specifically, from Wagner Vineyards Estate Winery at Seneca Lake.

The kit retails for about CAD$230 (CAD$1.00 is about US$0.75) and comes complete with all necessary winemaking ingredients as well as peel-and-stick labels, shrink capsules, and so-called 2+1 corks (#9, 1-1/2”) for 30 bottles.

I am excited to give this kit a go as it bears Matteo Meglioli’s name. He is the enologist (oenologist for my Canadian friends) at Mosti Mondiale and, well, in a nutshell, he knows his stuff. A brilliant individual.

This kit will produce about 23 liters (6 gallons) — the equivalent of 30 standard 750-mL bottles — of what should be delicious Riesling. According to Mosti Mondiale’s website, this kit produces “a unique dry Riesling with mineral notes on the nose and notes of citrus, apples and fresh fruit on the palate, brought together by a crisp and refreshing acidity.” Given that the juice was sourced from a cool-climate vine-growing region, I suspect the wine once aged will have a typical petrol character due to a compound known as TDN characteristic of Riesling. For diehard chemistry geeks, TDN is a C13−norisoprenoid with the chemical name 1,1,6-trimethyl-1,2-dihydronapthalene.

I haven’t made Riesling in ages although it was one of our major products when I had my commercial winery in Niagara (Ontario). We made Riesling-based wines in just about every style: dry, off-dry, semi-sweet, sparkling and icewine. But this Finger Lakes Riesling will be totally dry.

MAKING THE WINE

I just started this kit today, and I’ll be following the kit’s instructions to the letter to make sure I produce a wine as intended.

After pouring the content of the bladder into a pail, I ran juice samples through my lab to measure some key parameters (shown below) that will help me monitor progress and to identify and prevent any potential problems.

Brix / SG = 21.2 / 1.088

TA = 5.14 g/L

pH = 3.42

Free SO₂ = 6.63 mg/L

Total SO₂ = 40.2 mg/L

YAN = 240.2 mg/L

NTU = 316

A₄₂₀ / A₄₄₀ / A₅₂₀ = 0.076 / 0.054 / 0.017

The measured Brix should yield just a touch over 12% ABV (alcohol by volume).

TA and pH are just perfect. I don’t know if the juice was processed for tartrate stability, and so, during alcoholic fermentation (AF), TA can either increase or decrease due to yeast producing succinic acid and depending if there is any potassium bitartrate formed and precipitated. But I don’t expect a large change, and therefore, the final TA should be in the perfect range for a dry-style Riesling.

Free and total SO₂ are low and will therefore not be an issue for yeast to perform its metabolic conversions.

YAN, or yeast assimilable nitrogen, is a measure of the amount of nitrogen available that yeast can assimilate into cells and carry out their metabolic activities. A YAN of 240 mg/L is quite sufficient for a Brix of 21.2. The kit does provide a packet of yeast nutrients to be used as a booster later on during the AF.

NTU, or Nephelometric Turbidity Units, is a measure of the turbidity of the juice. The maintenance of a sufficiently high level of turbidity is essential for white wine production, with solid particles acting as a source of lipids for yeast growth under anaerobiosis (absence of air). Ribéreau-Gayon et al. (2012) recommend 100–250 NTU to minimize volatile sulfur compounds (VSCs) production, and so we are good here with 316 NTU. Contrary to many kits, this one does not add any bentonite to the juice, likely “to minimize any aroma or flavor stripping,” according to Nino Piazza at Mosti Mondiale.

A₄₂₀, A₄₄₀ and A₅₂₀ are absorbances measured at wavelengths of 420, 440 and 520 nm. These will help evaluate color and identify any oxidation issues, particularly during cellar aging.

Once I confirmed that the juice chemistry was all good, I added the supplied packet of dried white raisins, which are meant to impart additional aromas and flavors, and then added the packet of Lalvin EC-1118 — a workhorse yeast. I usually rehydrate yeast before inoculating the juice, but I did want to follow instructions strictly, and so I sprinkled the yeast pellets on the surface and placed the lid on the pail.

And now we wait. Fermentation should start within 24–48 hours.

Stay tuned for updates.

REFERENCES

Ribéreau-Gayon, P., D. Dubourdieu, B. Donèche and A. Lonvaud. 2012. Traité d’œnologie, Tome 1 – Microbiologie du vin. Vinifications. 6e édition. Dunod, Paris.