Fermenting Beer with Lallemand WildBrew Philly Sour Yeast

Published: November 20, 2025 at 8:39:30 PM UTC

This article is a detailed guide for using Lallemand WildBrew Philly Sour Yeast in brewing. It combines a Philly Sour review with lab data, recipe planning, fermentation management, and sensory outcomes. This information helps brewers decide how to incorporate this sour beer yeast into their brewing lineup.

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Lallemand WildBrew Philly Sour is a Lachancea thermotolerans strain developed at the University of the Sciences in Philadelphia. It was commercialized by Lallemand Brewing. This yeast produces moderate lactic acid and ethanol in a single fermentation step. This makes it a time-saving option for brewing Berliner Weisse, Gose, Sour IPAs, and sessionable American wild ales.

The guide will cover when to pitch WildBrew Philly Sour, typical attenuation and pH trajectories, and recipe ideas. It includes a BIAB example. It also explains how the strain interacts with hops, fruit additions, and co-fermentation partners. This interaction shapes the final acidity and flavor.

Key Takeaways

WildBrew Philly Sour (Lachancea thermotolerans) produces lactic acid and ethanol in one fermentation step.
It shortens souring timelines compared with kettle souring or long mixed-culture aging.
Best suited for Berliner Weisse, Gose, Sour IPA, and session sour styles.
Pitching time, temperature, and co-fermentation choices affect final acidity and fruit character.
The article provides lab specs, a BIAB recipe example, and practical packaging advice for US brewers.

Why Lallemand WildBrew Philly Sour Yeast is a Game-Changer for Sour Brewing

Lallemand WildBrew Philly Sour Yeast revolutionizes sour brewing by merging lactic acid and ethanol production in a single fermentation step. This innovation eliminates the need for separate kettle souring or prolonged mixed-culture aging. It still achieves the desired bright acidity.

Under standard conditions, the culture typically brings the pH into the 3.2–3.5 range. This level of tartness is comparable to what quick souring yeast can achieve. It makes it an excellent choice for brewers aiming for a sharp profile without additional steps.

Turnarounds can be swift. Many home and craft batches finish primary fermentation around ten days. This supports faster packaging cycles, ensuring an easy sour beer and consistent tap rotation.

The strain exhibits high attenuation and strong flocculation. These traits enhance fermentability and clarity. As a result, bottles and kegs condition sooner, and the beer appears cleaner on pour.

Head retention is superior to some sour strains, which is crucial for sessionable styles. Brewers seeking a Berliner Weiss shortcut find this particularly useful. It balances light body with lively acidity effectively.

Hops tolerance allows for the use of this yeast in hop-forward sours, such as Sour IPAs, without compromising the souring function. This opens up style possibilities for brewers who desire tartness alongside assertive hop character.

Single-step souring for simpler processes
pH reach comparable to quick souring yeast
Rapid turnaround suitable for easy sour beer schedules
High attenuation and flocculation for clearer beer
Good head retention for sessionable pours
Hops resistance expands recipe options

Product Specs and Laboratory Performance of the Yeast

WildBrew™ Philly Sour is a Lachancea species, chosen at the University of the Sciences in Philadelphia. Lab sheets from Lallemand reveal typical pH in standard wort ranges from 3.2 to 3.5. Titratable acidity often falls between 0.1–0.4% lactic acid under standard conditions.

Reported Lachancea attenuation is high, with homebrew examples showing significant sugar consumption. An OG of 1.063 drops to an FG near 1.013. The yeast's high flocculation ensures it settles and clarifies the beer without aggressive filtration.

Lallemand advises a fermentation temperature range of 20–25°C (68–77°F) for optimal performance. Brewers should anticipate fermentation starting slowly. Visible activity may take 24–48 hours to appear after pitching.

Alcohol tolerance is around 9% ABV, so plan target strength accordingly.
Recommended pitch rates of 1–1.5 g/L help optimize acid production and balance attenuation.
Occasional mild sulfur notes may occur during active fermentation and usually dissipate before packaging.

Lab metrics and practical notes form the core Philly Sour specs brewers need for sour or mixed-fermentation beers. Adhere to the listed fermentation temperature and pitch guidance. This will help balance acid production, carbonation targets, and final clarity.

Planning a Recipe for Philly Sour: Mash, Malt Bill, and Target ABV

Begin with a 5-gallon test brew goal: OG 1.063, FG 1.013, and ABV near 6.4%. Use the BIAB sour recipe as a starting point with Philly Sour yeast. This approach minimizes variables, allowing you to understand how mash and pitching influence acidity and fruit flavors.

For a sour beer malt bill, aim for delicate acidity and bright fruit notes. A mix of 3 kg Pale Ale Malt, 600 g flaked oats, and 500 g CaraGold is practical. This combination provides body with a touch of sweetness and a silky mouthfeel, enhancing the beer's juice-like quality.

Adjust the mash temperature based on your desired flavor profile. A Berliner mash schedule with a 65°C strike in BIAB ensures good conversion and fermentable wort. Lower mash temperatures increase simple sugars, enhancing stone fruit and tropical flavors in the beer.

To preserve dextrins and achieve red-apple and textured notes, raise the mash temperature. Higher temperatures result in more unfermentable sugars. These sugars interact with the yeast, altering the beer's acidity and balance.

Consider alcohol tolerance when planning the OG. Philly Sour can handle up to 9% ABV, offering flexibility for stronger sours. Remember, acid production is more dependent on pitch rate and wort composition than OG. Aim for a target pH and adjust the mash profile and adjuncts accordingly.

To minimize off-flavors and protect the sour character, follow simple preparation steps. Filter brewing water to remove chlorine or chloramine. Use sodium metabisulfite if necessary to neutralize tap chemicals before brewing. Sanitize equipment and pre-measure grains and adjuncts to streamline the mash and BIAB process.

Example BIAB sour recipe (5 gal): Pale Ale Malt 3 kg, Flaked Oats 600 g, CaraGold 500 g.
Mash target: strike 65°C for full conversion with BIAB; follow a Berliner mash schedule for consistency.
Boil: 60 minutes; OG target 1.063 for ~6.4% ABV.

When scaling recipes, maintain a balance between fermentability and body. This balance ensures Philly Sour showcases bright acidity without becoming too thin. Monitor pH at mash out and after fermentation to refine future batches.

Hops and Philly Sour: Resistance to Hops and How That Changes Your Hop Strategy

Lallemand WildBrew Philly Sour exhibits significant hop resistance. This allows brewers to create hop-forward sours without hindering lactic fermentation. It's possible to achieve higher IBUs than with traditional lactobacillus strains while maintaining clean souring.

Practical batches show the trade-offs in hopping sour beers. One test included Magnum 10 g at 60 minutes for bittering. Then, Mosaic and Citra 40 g each were added in a 20-minute hop stand. The final samples showed solid bitterness but significant hop aroma loss compared to expectations.

To preserve hop character, increase late additions or plan aggressive dry hopping after fermentation slows. The yeast will mute some volatile oils. Therefore, larger late additions are necessary to offset this effect.

Choose hop varieties with intense, stable aromatics—Citra, Mosaic, and Amarillo are common picks for sour IPA projects.
Consider post-fermentation dry hops once pH stabilizes to reduce hop aroma loss during active souring.
If bitterness is key, rely on early bittering additions since Philly Sour hop resistance permits higher IBUs without stopping acid production.

When designing a sour IPA, balance acidity and bitterness. Use Philly Sour as your sour IPA yeast and adjust hop timing to favor aroma retention. Expect some attenuation of volatile hop notes. Plan additions accordingly to achieve the desired hop profile in the finished beer.

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Pitching Rates, Fermentation Management, and Impact on Acidity

Pitching rate is crucial for acid production with Lallemand WildBrew Philly Sour. Lallemand and brewers agree that 1–1.5 g/L is optimal. For example, using two 11 g packs in 22 L results in about 1 g/L. This pushes the culture towards stronger lactic acid production.

Lower pitch rates, near 1 g/L, boost lactic activity and sourness. Straying from the recommended range can reduce acid production. Brewers aiming for sourness must focus on precise measurements, sanitation, and wort composition.

Fermentation temperature significantly impacts yeast behavior and attenuation. Lallemand suggests 20–25°C (68–77°F) as the ideal range. Many brewers ferment between 22–27°C, with some starting at 30°C before cooling to 25°C. Fermenting too cold, at 18–20°C, can lead to early flocculation and under-attenuation.

Temperature changes affect activity more than flavor categories. The main risk is yeast drop-out if it gets too cold. Maintaining a gentle temperature rise can help complete attenuation and sustain acid production.

Expect a short lag: visible signs often appear 24–48 hours after pitch.
Acid production typically leads ethanol production; souring can peak early in primary.
Primary fermentation commonly finishes in about 10 days for many beers, though cooler or heavier worts take longer.

Philly Sour is highly flocculant and may settle before full sugar conversion. Monitor gravity and rouse the yeast if acid production stalls. This step ensures both final gravity and desired acidity.

Sugar type affects flavor and acid dynamics. Worts with sucrose or fruit sugars can introduce peach notes. Higher mash temperatures yield more dextrins, tilting the flavor towards red apple. Lactose is not fermented by this strain, so it can be added post-fermentation to retain sweetness without reducing acidity.

Fruit Additions and Timing for Optimal Flavor with Philly Sour

Timing fruit additions in Philly Sour impacts acidity, aroma, and sweetness. Yeast produces most acid early, then more ethanol later. This timing affects whether fruit sugars enhance acidity or contribute to flavor and body.

Adding fruit early, around day 1–4, allows sugars to ferment with the culture. This stage increases tartness and integrates fruit into the beer's sour backbone. Brewers seeking a strong fruit character often add fruit here for a tangier finish.

Mid-fermentation additions, around day 4–5, balance acid and alcohol extraction. This timing is ideal for delicate fruits or blends, aiming for balanced acidity and fruit esters. A brewhouse split a batch, adding pineapple on day four to one tank and rhubarb to another, achieving a lively fruit presence without overwhelming acidity.

Late additions, after primary souring, focus on aroma and residual sweetness. Fruit added late doesn't ferment fully, leaving more sugar and fresh fruit notes. Homebrewers aiming for syrupy mouthfeel or pronounced aroma often choose this timing.

Mango and pineapple pair well with Philly Sour, creating bright tropical notes that complement the strain’s profile.
Blueberries can give a subtle purple hue and delicate flavor; a brewer who added 2 kg to a 5 gal batch after one week reported mild blueberry presence.
Rhubarb and roasted pineapple provide tart and caramelized layers when used carefully at mid-primary.

Decide on fruit weight based on desired intensity. Increasing fruit in later batches intensifies flavor without increasing acidity. Monitor gravity and pH after each addition to track fermentability and final souring impact.

Process fruit with sanitation in mind. Frozen fruit often arrives pasteurized and can be thawed and pureed. Roasting concentrates flavor and reduces microbial load for raw fruit. Sanitize surfaces and consider a light heat treatment for fresh fruit to protect the culture and control outcomes.

Keep records of timing, quantity, and preparation for each batch. Small changes in when to add fruit and how it’s processed will alter the final beer. Thoughtful planning and testing will help you dial in the right balance between acidity, alcohol extraction, and fruit character in your Philly Sour fruit timing experiments.

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Using Philly Sour in a Brew-in-a-Bag (BIAB) Workflow

Creating a simple BIAB sour recipe begins with a controlled mash. Start by heating strike water to around 65°C. Then, add the bag with crushed grain. Maintain this temperature for the desired conversion and to shape the malt sugar profile. This profile is crucial for interacting with Lallemand WildBrew Philly Sour.

Once the mash is complete, lift the bag and bring the wort to a boil lasting 60 minutes. Add bittering hops early in the boil. Next, perform a hop stand at 80–90°C for late hop aroma. Finally, chill the wort to the ideal pitching temperature. Sprinkle the dry Philly Sour yeast directly onto the wort for the dry-pitching method.

The documented BIAB workflow shows an example gravity of just over 1.063 before fermentation. Pitch the yeast within the recommended, temperature-controlled range. This OG provides enough fermentables for acid production and balanced body in your Brew-in-a-Bag sour beer.

Sanitation: Filter to remove chlorine or chloramine from water. A small dose of sodium metabisulfite is optional for extra protection.
Equipment: Standard BIAB sanitation of the kettle, bag, and fermenter reduces risk of unwanted microbes even when using single-strain Philly Sour.
Mash control: Precise mash temperature in BIAB helps tune the sugar profile and final acidity when using the Philly strain.

Fruit additions work well in BIAB workflows. Transfer cooled wort to the fermenter, then add fruit or adjuncts according to your acid-production plan. Adding fruit after primary transfer helps preserve fresh aroma and prevents excessive pectin haze in your BIAB sour recipe.

Advantages of a BIAB Philly Sour approach include a single-vessel setup that simplifies all-grain souring and tight mash control that impacts flavor and acid development. This workflow scales from 10-liter test batches to larger homebrew volumes with minimal extra gear.

Follow routine sanitation and water prep steps, keep mash temps steady, and time fruit additions to your strategy. These steps help ensure a consistent BIAB Philly Sour or Brew-in-a-Bag sour beer that reflects the yeast's character and your recipe choices.

Fermentation Timeline and What to Expect During Primary

The Philly Sour fermentation timeline is typically straightforward. A lag phase of 24–48 hours follows pitching. Krausen or bubbling signs may emerge during this period.

In the early stages of primary sour fermentation, yeast and bacteria concentrate on acid production. pH levels often plummet to 3.2–3.5 within the first days. This acidity is what gives the beer its distinctive tartness.

Following acid production, the focus shifts to alcohol creation. Attenuation continues, and many batches reach their final gravity in about ten days. Brewers often extend primary fermentation to three weeks. This ensures both fermentation and acid development are fully complete.

Signs of fermentation Philly Sour include visible krausen, active bubbling in the airlock, and a steady fall in gravity readings.
Mild sulfur or savory notes can appear during active fermentation. Those aromas usually fade as conditioning progresses.
Use both gravity and pH checks to confirm progress. Aim for a pH near 3.2–3.5 for pronounced sourness.

Practical steps can help avoid fermentation stalls. Gentle rousing or raising the temperature to 22–27°C can prevent premature flocculation. Regular gravity checks are essential to track true progress.

Fruit additions are often made during primary for integration or after primary for a brighter aroma. The timing depends on the desired fruit character and previous guidance.

Post-primary handling involves clarity, fruit integration, and carbonation planning. Some brewers transfer to secondary for conditioning, while others prefer longer primary times. This approach minimizes oxygen exposure and preserves acidity balance.

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Co-Fermentation and Sequencing with Other Yeasts and Bacteria

Start by avoiding Philly Sour co-pitching with other yeast or bacteria on day one if your goal is clean lactic acidity. When standard Saccharomyces strains are present at the outset, they tend to outcompete Lactobacillus and reduce lactic output.

Use a sequential fermentation plan to preserve the quick souring Philly Sour offers. Allow the Philadelphia strain to run primary souring for roughly four days or longer until you hit target pH. After that, pitch a second yeast to shape aroma and ester profile.

Consider pitching a Saison strain like Belle Saison after primary souring to add peppery, phenolic notes without killing acidity.
Introduce Brettanomyces later to develop funk and complexity; Brett and Philly Sour pair well when Philly Sour has initial dominance.
Add Lactobacillus in a controlled secondary if you want layered acidity, knowing it will extend aging time.

Mixed culture strategies require patience and planning. Monitor pH and gravity before pitching subsequent organisms so you know when sugars and acidity are at the right levels for the next culture.

Keep sanitation tight and map your timeline against desired alcohol and flavor targets. Mixed culture strategies and sequential fermentation change both aging needs and final profile, so plan tank space and blending accordingly.

Practical tips: test a small pilot batch when combining Brett and Philly Sour to understand how funk develops over months. Track acidity frequently to avoid over-souring when multiple microbes are involved.

Practical Packaging and Conditioning Advice for Philly Sour Beers

When packaging Philly Sour, aim for 2–3 weeks in primary fermentation. This ensures fermentation is complete. Wait for gravity readings to stabilize over a few days before moving to conditioning steps.

For bottle conditioning, cold-crash or stabilize first if fruit was added. Fruit can introduce residual sugars that ferment further in bottles. Use precise priming sugar calculations and choose strong bottles for higher carbonation.

Bottle conditioning can be successful with carbonation drops or gueuze-style bottles. These bottles come with corks and wire cages for safety. Wire cages or flip-top bottles help manage unexpected pressure.

Use calibrated priming calculators to avoid over-carbonation.
Consider a short lagering period after carbonation to help settle fruit haze.
Label batches with dates and gravity for future reference.

Kegging sour beer offers quicker control over carbonation and reduces bottle risks. Force-carbonate at low pressures and sample frequently. Philly Sour can attenuate highly, leading to unexpected dryness.

If bottling after active fermentation, consider chemical stabilization or pasteurization to prevent bottle bombs. Cold-conditioning for a week or two before priming can reduce yeast activity without harming acidity.

Clarity may return after conditioning, but fruit and microbes can reintroduce haze. Use fining agents like gelatin or isinglass for clearer beer. Alternatively, extend cold conditioning to settle solids.

For beers with only Philly Sour, expect predictable behavior and quicker drinkability.
For blends with Brettanomyces or Lactobacillus, plan on months of evolution and monitor flavor over time.

Keep a log of your conditioning and packaging choices. This log will help refine priming amounts and decide between bottle and kegging. It will also improve consistency in future Philly Sour brews.

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Tasting Notes and Sensory Profile from Test Batches

Appearance varied from pale straw to deep purple with fruit additions. A 5 gal batch with 2 kg blueberries turned a clear purple. Head retention was modest, often falling back quickly. Moderate carbonation enhanced acidity and kept the beer lively.

Aroma and initial impressions were clean and bright, leaning towards Berliner Weiss. Hop aroma was often subdued, making hop-forward profiles less pronounced. This was observed in several trials.

Taste delivered a sharp, puckering sourness. Many found the acidity more pronounced than expected. Fruit additions altered the flavor profile. Low fruit loads offered subtle blueberry notes, while heavier additions brought out pineapple or rhubarb.

Esters played a significant role based on wort composition. Wort with more simple sugars and sucrose introduced stone-fruit and peach-like esters. Maltier worts emphasized red-apple and bready tones. These changes influenced the flavor without adding Brett-like funk.

Fruit impact: 2 kg blueberries in 5 gal = vivid color, light blueberry aroma, restrained fruit intensity.
Acidity: pronounced puckering sourness; carbonation level crucial to balance sharpness.
Hop perception: muted in finished beer; plan hop additions accordingly.

Drinkability remained a strong point. Testers found the beers sessionable and consistent, perfect for repeat pints. Brewers appreciated the Philly Sour tasting notes, aligning with quick-turn sour brewing goals. It offered a tasty and approachable alternative to long mixed-culture aging.

Tips, Troubleshooting, and Best Practices from Brewers Using Philly Sour

For steady attenuation and lactic acid production, keep fermentation between 22–27°C. Brewers find that temperatures around 18–20°C can slow down activity and cause early flocculation. This results in under-attenuation.

Pitch at 1–1.5 g/L to achieve the desired acidity. The pitch rate directly influences the final pH, leading to sharper acid levels. It's crucial to monitor gravity and pH daily in the first week to track progress.

If fermentation starts slowly, give the yeast 24–48 hours before intervening. Check temperature and pitching rate first.
For low acidity, review pitch rate, fermentation temperature, and wort sugar makeup. Reducing pitch rate can raise lactic acid levels.
If early flocculation occurs, gently rouse the yeast or raise temperature to keep activity going.

Fruit timing is key to achieving balance. Add fruit around day 4 to capture a mix of acid and alcohol-derived flavors. Adding fruit earlier favors higher acid extraction. Adding it later emphasizes fermented fruit character.

Philly Sour will not ferment lactose, so lactose can be used to retain residual sweetness when desired. When layering a second yeast such as Saison, pitch it after primary souring, near day 4, to preserve acid development rather than co-pitching.

Muted hop aroma? Boost late additions, use a hop stand, or increase post-primary dry hop amounts. Expect some hop loss with this strain.
Sanitation matters even with single-strain souring. Prevent unintended microbes by keeping equipment and fruit handling clean.
When conditioning with fruit or extra sugars, use sturdy bottles or a keg to manage carbonation safety.

Record keeping is essential for troubleshooting Philly Sour. Track pitch rate, temperature, pH, gravity, and fruit dose. These notes help diagnose issues when batches don't meet expectations.

Adopt best practices sour yeast brewers trust: consistent temps, measured pitch rates, phased fruit additions, and regular monitoring. These steps reduce surprises and improve repeatability.

Conclusion

Lallemand WildBrew Philly Sour offers brewers a quicker, more consistent path to clean, fruit-forward sour beers. It produces lactic acid and ethanol in a single fermentation. This results in expected pH outcomes around 3.2–3.5, high attenuation, and near 9% alcohol tolerance. It's suitable for many sour styles, including hopped variations like Sour IPA.

Success hinges on a few key factors. Pitch at roughly 1–1.5 g/L for acid production. Hold fermentation between 20–27°C. Add fruit mid-fermentation for balanced flavor. The aromatic profile will be cleaner and more restrained than mixed-culture sours. Adjust hop and adjunct choices accordingly.

So, should you use Philly Sour? For brewers aiming for speed, consistency, and simplicity, the answer is yes. It's a practical tool for crafting approachable, drinkable sours. It also allows for experimenting with fruit and hop-driven expressions without the complexity of kettle souring or long-term barrel aging.