Strata hops for passion fruit and dank aroma in modern IPAs

What Strata brings to a beer

Strata came out of a breeding programme in Oregon, run by Oregon State University with the hop company Indie Hops. It reached commercial brewers in the late 2010s. Alpha acids are high, usually in the low teens. Brewers use it for aroma far more than for bitterness.

The aroma is two-sided. The top notes are passion fruit, grapefruit and ripe berry. Underneath sits a dank, resinous character that some tasters compare to cannabis. In a hazy IPA the fruit usually leads. In a clear West Coast IPA the resin has more room to speak. Both sides arrive together, so you cannot keep one and drop the other.

Where the dank character comes from

Dank is a catch-all word for resinous, sulphurous and herbal notes. Part of it comes from sulphur-containing compounds, some of which are thiols. Thiols are powerful at very low concentrations, which is why a small change in dose or freshness can swing the aroma from passion fruit to garlic. The same ideas apply to Columbus, the classic dank American hop.

Strata sits between the two worlds. The fruit keeps the dankness pleasant. Lose the fruit through age or oxygen and what is left tastes heavy and savoury.

A dosing plan for 1,000 litres of hazy IPA

For a hazy IPA at 6% ABV, bitter lightly to about 25 IBU from a clean, high alpha hop. A 60 minute charge of a 15% alpha hop at 28% utilisation needs 25 x 1,000 / (0.15 x 0.28 x 1,000), about 595 g. Strata earns its place later.

• Whirlpool at 78 to 80 °C for 20 minutes: 2 g per litre, 2 kg in total.
• First dry hop on day two of fermentation, at 18 to 20 °C: 2 g per litre, 2 kg.
• Second dry hop after fermentation slows: 3 g per litre, 3 kg.

That is 5 g per litre in the dry hop and 7 g per litre across the beer, a typical hazy IPA rate. For a clear IPA with the same hops, cut the dry hop to 3 or 4 g per litre. Heavy dry hopping brings polyphenols and plant matter into the beer. A drying, harsh finish follows.

Hop creep and the first dry hop

Hops carry enzymes that break down starch and dextrins into fermentable sugar. Add a heavy charge before fermentation has finished and the yeast can start again, raising attenuation by a few gravity points. Brewers call it hop creep. In a sealed tank it also makes extra CO2 and pressure.

Early dry hopping during active fermentation is common in hazy IPA because it brings extra flavour from yeast biotransformation. If you do it, check the gravity again after the beer has apparently finished. Wait until two readings 24 hours apart agree before you crash. Packaging a beer that is still creeping risks over-carbonated cans.

Pellets, cryo and extracts

Most Strata reaches India as T90 pellets in foil. If you want more aroma per kilo and less vegetal matter in the tank, ask whether a concentrated lupulin product exists for the variety you want. Our guide to hop extracts and cryo hops covers the trade-offs, including lower dry hop rates and a higher price per kilo.

Compare that with pellets and whole cone for the base hop bill. Whatever format you buy, cost the hops as a per litre figure, not a per kilo price. A cheaper hop used at a higher rate can cost more.

Oxygen, the real enemy of fruit

The passion fruit goes first when oxygen enters. Dry hopping through an open manway lets air in. Purge the hop dosing port with CO2 before and after the charge. Transfer closed, from tank to tank with CO2 pushing the beer. In a warm country, hop aroma loses ground even faster, so keep the cellar and package cold.

Measure dissolved oxygen at packaging if you have a meter. A figure under 50 ppb is a common target for hop-forward beer. Many small breweries do not measure at all and then wonder why their IPAs fade in a month.

Bringing the process together

A good Strata beer is a stack of small controls: a clean base, a measured dose, a closed transfer and a cold chain. Each one sounds minor. Together they decide whether the beer tastes of passion fruit in week six or only in week one. Learning to design that stack with data, rather than copying a recipe, is what we teach in Advanced Brewing Science.

Common questions

What does Strata taste like?

Passion fruit, grapefruit and berry over a dank, resinous base.

How much Strata should I dry hop with?

Hazy IPA brewers commonly use 5 to 8 g per litre in total across two dry hops. Clear IPAs use less, around 3 to 4 g per litre.

What is hop creep?

Enzymes in dry hops break down residual starch and dextrins, so the yeast ferments again. Gravity drops further and CO2 rises. Wait for a stable gravity before packaging.