When Wasted Degrees switched to multi-strain kveik yeast, they didn’t just change their fermentation profile — they cut their dry hop rate, improved their yield, and ended up with a better beer.

There is a moment in many breweries when a process that has always worked begins to feel like it could work better. For Conall and Jack Low, the brothers behind Wasted Degrees in Perthshire, Scotland, that moment arrived not in the brewhouse but at a bar at SIBA’s Beer X in 2025, when two Norwegians appeared with a backpack full of yeast.

“Not really what we were expecting,” admits Jack. But the encounter proved consequential. Wasted Degrees had just won best IPA in Scotland, and the conversation that followed set in motion a series of changes to how they ferment their flagship 5.9% hazy IPA — changes that have since delivered a 30% reduction in hop usage, a 7% increase in total packaged volume, and, by their own account, a better-tasting beer.

From hop-forward to flavour-focused

Before the switch, Wasted Degrees ran a conventional fermentation profile for a modern hazy IPA. The yeast of choice was London Fog from various suppliers, pitched at 18°C with a free rise to 22°C. Fermentation ran six to seven days, with a fresh pitch of dry yeast each batch.

The hop bill was built for intensity: on the hot side, El Dorado at 2.5 g/L 10 minutes from the end of boil, and 2.5 g/L added at whirlpool, targeting a smooth, low-IBU profile. On the cold side, a single dry hop addition of 12 g/L of Mosaic and Azacca was dosed on day three during active fermentation.

“A shift in mindset and taking a step back to think about what we were trying to achieve led us to kveik,” Jack explains. Three aims were identified for the reformulated IPA: flavour, cost economies, and yield. The team had grown concerned that escalating hop rates were adding cost that would need to be passed on to the consumer, while also risking hop-burn. There was also a yield consideration: high solids loadings in-tank translate directly into beer losses.

The underlying question was whether yeast could contribute more of the aroma work that hops had been doing, and whether a reduction in hop rate could follow as a result.

Fermentation protocol

For the reformulated recipe, Wasted Degrees selected two strains from Kveik Yeastery, a Norwegian supplier specialising in dried multi-strain Kveik, running K.1 Voss and K.22 Stalljen in combination.

Two 300g packs were co-pitched into a 16hl batch, giving a combined pitch rate appropriate for the vessel size. Fermentation was set at 36°C with a free rise to 40°C, conducted at atmospheric pressure in a DPV with an airlock. Antifoam was used both in-tank and in the airlock.

The grist composition (pale, wheat, dextrin, Vienna), water profile (2:1 chloride-to-sulphate ratio), and hop varieties were the same to limit changes to get a good understanding of what the yeast could offer.

The revised hop schedule reflected two adjustments. On the hot side/ whirlpool, the El Dorado rate was reduced from 5g/L to 2.5g/L. The rationale was fermentation kinetics: kveik ferments rapidly and vigorously, and the team observed that the aggressive CO2 evolution during early fermentation risked stripping volatile hop aromatics contributed on the hot side. Reducing the hot-side rate was therefore a deliberate response to the changed fermentation behaviour rather than a simple cost saving.

On the cold side, the dry hop addition was reduced from 12g/L to 8g/L, and the timing was shifted. Rather than dosing during active fermentation on day three, the team waited until fermentation was complete before dropping the tank temperature to 22°C and dry hopping. Pellets were added through the top manway and mixed by briefly bubbling CO2 through the carb stone at 2L/min.

The decision to dry hop post-fermentation, rather than mid-fermentation as previously, is technically significant: dry hopping during active fermentation introduces biotransformation potential — where yeast enzymes can modify hop compounds — but also increases the risk of aroma loss through CO2 scrubbing.

Post-fermentation dry hopping preserves more of the added hop character in the finished beer, though it foregoes biotransformation. The shift in timing, combined with the lower rate, meant they were relying more heavily on the yeast itself to generate aroma.

They experienced significantly reduced lag time, and fermentation was underway within one hour of pitching. The batch attenuated to 78% and was complete within three days. “The aroma on day one walking back into the brewery was phenomenal,” Jack says. “A range of citrus fruits through to peach and apricot, and this was with significantly fewer hot-side hops than we would typically add to a NEIPA, or even our Pilsner.”

The ester profile observed, citrus, peach and apricot, is consistent with the known characteristics of both Voss (orange, tangerine, citrus) and Stalljen (tropical fruit, mango, pineapple), suggesting the yeast was contributing substantially to the aroma development that had previously been driven primarily by hop additions.

Results

The finished beer performed well on sensory evaluation. “The flavour profile is equally as intense in taste and aroma yet presents as more integrated rather than layered,” Jack reports. “It made for a smoother drinking experience, with no distractions of upfront or volatile tasting notes subsiding over time.”

The absence of the “layered” quality they describe is consistent with a reduction in dry hop rate: very high dry hop additions can produce a pronounced, sometimes sharp hop character that dominates early in the glass and fades. A lower rate, combined with yeast-derived esters, may produce a more unified aroma profile.

Process metrics were equally encouraging. Total hop usage was reduced by 30% between otherwise identical batches of the same recipe. Total packaged volume increased by 7%, attributable to lower beer losses from reduced solids in-tank — a direct consequence of the lower dry hop rate. Jack also notes that further gains may be achievable: “The potential could be greater subject to managing fermentation temperatures and other associated variables.”

The brewery also highlights supply chain resilience as a factor worth considering. “Sourcing a core, flavour-driving ingredient from a non-volatile and geographically nearby source reduces risk in supply chain reliability,” they say, a consideration that has become increasingly relevant given hop market volatility in recent years.

For brewers considering a similar approach, the Wasted Degrees experience suggests that the relationship between yeast selection and hop rate is worth examining more deliberately. “Whether you have a challenge with shipment cost, storage capacity, or losses and inefficiencies from solids in-tank, the benefits are clear and multifaceted,” Jack concludes.

Kveik Yeastery is a Norwegian yeast supplier specialising in dried multi-strain kveik yeasts for both homebrew and commercial use. Where most suppliers offer isolated single strains, the company focuses exclusively on multi-strain blends, with the aim of delivering greater complexity and versatility across a wide range of beer styles. Products are sold and shipped directly to Great Britain.

Wasted Degrees is a multi-award-winning brewery owned and operated by brothers Conall and Jack Low, based in Perthshire, Scotland. The business began as Conall’s hobby a decade ago, starting with a homebrew kit in their parents’ garage.

The brewery now produces up to 29,000 litres per month, with sales reaching 13 countries, though the majority is sold within an 80km radius. Built without external debt or investors, Wasted Degrees is a consistent award-winner with SIBA, recognised for its IPA, barrel-aged beer, amber, and lager. In 2027, the brothers will begin construction of a new £2 million production facility and taproom in Pitlochry — the first brewery in the town in over 155 years.