Callista hops for apricot and berry in a hoppy lager

A fruit hop with low alpha

Callista was released by the Hüll hop research centre in Bavaria in 2016, one of the newer German aroma varieties bred for craft brewers. Alpha acid is low, typically 2 to 5%, which places it firmly in the aroma camp.

Its aroma is fruit led: apricot and passion fruit first, then red berries and a little citrus. Tasters often describe it as juicy rather than resinous. That makes it different from classic German aroma hops, which lean floral and spicy. A lager hopped with Callista smells of ripe fruit rather than hay and pepper.

What a hoppy lager needs

A hoppy lager is a modern style: a clean, cold fermented lager with a hop aroma closer to a pale ale. The base stays light and dry, the colour pale and the bitterness moderate, often around 25 to 40 IBU. What sets it apart is a late hop and dry hop schedule that puts aroma at the front.

Callista fits because lager yeast leaves so little fruit of its own. An ale yeast would add esters that blend into the hop. A lager yeast fermented at 9 to 12 °C mostly does not, so the apricot and berry come through cleanly. Our guide to brewing a hoppy lager at home covers the style in full.

Bitter with something else

With alpha around 3.5%, bittering a 20 litre batch to 20 IBU with Callista alone would take about 41 g at 60 minutes: 20 x 20 / (0.035 x 0.28 x 1,000). That is a lot of hop matter boiled for an hour, which adds grassy polyphenols and soaks up wort, while the fruit you bought it for boils away.

A better plan is a small 60 minute charge of a clean, higher alpha hop such as Magnum or Perle for most of the bitterness, then Callista late. Most of its value lies in the last few minutes of the boil, the whirlpool and the dry hop.

A 20 litre schedule

For a hoppy lager at about 5% ABV and 30 IBU on a Pilsner malt base:

• 60 minutes: clean bittering hop for about 22 IBU.
• Whirlpool: 50 g Callista at around 80 °C for 20 minutes. This adds a few IBU as well as aroma.
• Dry hop: 60 to 80 g Callista, about 3 to 4 g per litre, near the end of fermentation or after the diacetyl rest.
• Fermentation: clean lager yeast at 10 to 12 °C, then a diacetyl rest and several weeks cold.

Dry hopping can restart a little fermentation through hop creep, so hold the beer at fermentation temperature for a couple of days after the dry hop and taste for butterscotch before cooling.

Pairing Callista with other hops

On its own Callista can taste a little soft. Many brewers pair it with a hop that adds edge. A spicy classic such as Saaz underneath gives a lager backbone. A brighter citrus hop on top makes the fruit pop.

When you blend, keep notes on what each hop added. A blend that works by accident is hard to repeat. A blend designed from an understanding of each hop's oils and timing can be rebuilt when one variety runs out.

Keep the fruit fresh

Fruit hop aromas fade quickly in warm, oxygen exposed beer. Keep pellets frozen and sealed until the moment you add them. Minimise oxygen pick up during the dry hop and packaging. Store the finished beer cold. In a hot Indian summer, a hoppy lager left at room temperature for a few weeks can lose most of its apricot and turn sweet and dull.

Water decides how the fruit lands

Many Indian brewers start with borewell water that is hard and high in bicarbonate. That suits a dark beer but fights a pale lager: mash pH runs high, bitterness turns coarse and hop fruit tastes muddy. For a Callista lager, dilute hard water with reverse osmosis water until the mash sits around pH 5.2 to 5.4.

Then adjust the mineral balance on purpose. Sulphate makes bitterness feel drier and sharper. Chloride makes the beer feel rounder and fuller. A hoppy lager usually wants a little more sulphate than chloride, but not the very high sulphate of an English IPA, which can make a light lager taste harsh. Measure your water once with a lab report rather than guessing from the colour of the kettle scale.

Your first step

Rub a few Callista pellets between your palms and write down the three aromas you smell before you read anyone else's description. Then brew the schedule above and repeat the exercise with the finished beer. Comparing the two lists shows you what the process kept and what it lost.

Common questions

What does Callista taste like?

Apricot and passion fruit first, then red berries and a little citrus. It is juicy and fruit led rather than spicy.

Is Callista a bittering hop?

No. With alpha around 2 to 5% it is an aroma hop. Bitter with a cleaner, higher alpha variety and use Callista late.

How much Callista should I dry hop a lager with?

Around 3 to 4 g per litre is a good start, so 60 to 80 g in a 20 litre batch.