Learning track
The mechanisms
Phenolics, acids, aroma chemistry, oxygen and the vineyard physiology underneath all of it — at the scope the evidence actually supports.
You want the mechanism, not the summary, and you want to know where it stops.
By the end: Follow a causal claim from vineyard to glass, and tell a demonstrated mechanism from a measured association from a trade convention.
21 steps
Each step is a full page in its own right — the same page search would send you to. Nothing here is a summary of something better.
1 The chemistry of alcoholic fermentation
What yeast actually do to sugar, why the schoolbook equation is a simplification, and where the flavour compounds come from.
2 Yeast: the organisms doing the work
Saccharomyces cerevisiae, the non-Saccharomyces species that start most spontaneous ferments, and what strain choice does and does not determine.
3 Tannin: what it actually is
The phenolic compounds behind astringency — where they come from, what they do in the mouth, and why they soften with age.
4 Astringency: why tannin is a feeling, not a taste
Astringency is a tactile sensation carried by the trigeminal nerve, not a taste carried by taste buds — which is why it behaves so differently from bitterness.
5 Acidity: the acids in wine and what each does
Tartaric, malic, lactic, citric and acetic acid — where they come from, how they differ, and why pH and total acidity are not the same measurement.
6 pH and total acidity are not the same thing
One measures acid strength, the other measures acid quantity — and a wine can be high in both, or high in one and not the other.
7 Sugar in wine: from grape to residual sweetness
Where grape sugar comes from, what happens to it in fermentation, and why residual sugar and perceived sweetness are two different things.
8 Alcohol: what ethanol does in the glass
Ethanol contributes body, carries aroma, changes how sweetness and bitterness are perceived, and is felt as warmth — several distinct effects that get bundled into one word.
9 Where wine aromas come from
Four origins — the grape, fermentation, oak and ageing — and why a tasting note is not a list of chemicals.
10 Esters and fermentation fruit
The compounds behind banana, pear-drop and tropical notes in young wine — made by yeast, and short-lived.
11 Terpenes and floral aromatics
Grape-derived compounds behind the rose, lychee and citrus-blossom character of Muscat, Gewürztraminer and Riesling.
12 Methoxypyrazines and green character
The compounds behind green pepper in Cabernet and grassiness in Sauvignon Blanc — and why sunlight on the fruit matters more than heat.
13 Thiols: passionfruit, grapefruit and box hedge
Sulfur-containing compounds released by yeast from odourless grape precursors — the chemistry behind Marlborough Sauvignon Blanc.
14 Oxygen: friend and enemy at every stage
Oxygen is needed in some quantities at some moments and damaging in others. What matters is how much, when, and to which wine.
15 Oxidation: the chemistry, the fault and the style
The same reactions that ruin a forgotten bottle also produce Oloroso, Madeira and Vin Jaune. Intent is what separates them.
16 Reduction: sulfur compounds and struck-match aromas
Low-oxygen conditions can leave volatile sulfur compounds in a wine — some transient and prized, some genuinely faulty.
17 Sulfur dioxide and sulfites
What SO₂ does in wine, why free and bound fractions are different, why every wine contains some, and what the label is actually telling you.
18 Colour: where it comes from and how it changes
Anthocyanins in black grape skins, their reaction with tannin over time, and why reds fade towards brick while whites deepen towards gold.
19 Ripening: several clocks running at once
Sugar, acid, tannin, colour and aroma each mature on their own schedule — which is why the picking decision is hard.
20 Vine balance
The relationship between crop load and leaf area — the idea that actually underlies the argument about yields.
21 Minerality: what the evidence actually shows
A word almost every taster uses, no agreed chemical definition, and no demonstrated route from vineyard rock to matching flavour.