Frequently Asked Questions
Real questions from production brewers.
How much Zinc Booster do I add?
Standard dose is 10 mL per hectolitre. For high gravity worts (above ~1.070 OG), double to 20 mL/hL. Add cold-side, in-line during fermenter fill. Each bottle size is matched to a tank size range so the dose rate is built in.
My fermentation stalled or is taking longer than usual.
Check pitch rate, yeast viability, and temperature control first. If you are repitching, confirm viability is above 90%. Nutrient deficiency is an underappreciated cause: wort zinc below 0.1 ppm is associated with sluggish fermentations. Range Brewing reported approximately 4 days faster fermentation after adding zinc cold-side.
For persistent issues, get in touch.
I'm on generation [X] and performance is declining.
Track lag time, attenuation rate, VDK cleanup time, and terminal gravity across generations. If any are trending in the wrong direction, that is your signal. If viability is above 90%, dosing Zinc Booster and Vitamin Booster cold-side on every batch can restore what the boil removes. Below 90% viability or changed flocculation, re-propagate from a fresh culture.
When should I harvest my yeast for repitching?
Harvest after crash cooling. Confirm terminal gravity and VDK pass first. Purge the first portion to drain, collect the middle fraction into a clean cubitainer, and stop before the last runnings. Store at 0 to 4 degrees C, use within 5 days (2 weeks max). Record viability before repitching.
What's the right strain for my beer style?
Browse our strain catalogue and filter by type or beer style. Each strain page includes specs, flavour profile, and a "Similar To" field for matching strains from other suppliers. For specific recommendations, get in touch with your setup and planned range.
I don't use zinc. I already add nutrients in the kettle.
Hot-side nutrients do not survive the boil in bioavailable form. Yeast scavenge zinc within the first hours of active growth, so it must be present cold-side in a usable form. Cold-side dosing during fermenter fill is the only reliable method. Under 1 cent per litre, works with any yeast.
Learn more about Zinc Booster · Read: The Role of Zinc in Brewing Fermentation
Is it worth buying a vitality testing instrument?
Viability testing (methylene blue + haemocytometer) is valuable for any brewery that repitches. Vitality testing is more complex and expensive. For most craft breweries, tracking lag time, attenuation rate, VDK cleanup, and terminal gravity across generations gives you the same practical information.
Our Repitching Technical Guide includes a generation tracking framework.
My VDK cleanup is slow. I'm getting diacetyl.
Temperature management first: diacetyl rest at 15 to 18 degrees C before crash cooling. Do not crash cool before VDK passes a forced diacetyl test. Slow VDK cleanup in later generations signals declining yeast health. B1 (thiamine), lost ~20% during boiling, is a cofactor for VDK metabolism. Cold-side vitamin supplementation can help.
For persistent issues, get in touch.
What's your pricing?
We supply direct to breweries. Pricing depends on strain, volume, and order frequency. Nutrient Boosters cost less than 1 cent per litre and are also available through Bintani. Get in touch with your brewery details for a quote.
Can I get a sample or trial first?
Yes. We can arrange trial quantities for new customers, including nutrient sample packs for controlled comparisons. Get in touch with your setup details (brew length, tank sizes, planned range) and we will put something together.
Still have questions? Talk to us.
We are always happy to discuss yeast, nutrients, or anything brewing.