Foraged Yeast Pilot Batch Tasting

Not all of last month’s Farm Bière wort made its way into the fermentor. Instead, a small portion was diverted into separate mini-fermentors to evaluate a dozen new foraged yeast isolates.

These yeasts were initially foraged from Maine, Massachusetts, and New Hampshire during summer/fall 2016 with the help of Flynn. Once captured, slurry was sent to Jeff Mello at Bootleg Biology for isolation. Fast-forward four months and one dozen isolates arrived in the mail ready for evaluating!

Drawing inspiration from Jeffrey Crane’s Great EBY Brett Experiment, I created my own cheap and easy method for yeast strain evaluation. Like Crane, I utilized plastic PET water bottles as fermentors. Below is a brief overview of my method:

1. Empty and sanitize twelve 700 ml plastic PET water bottles (I prefer Poland Spring Flip-Cap)
2. Add ~500-600 ml of cooled, sterile wort to each sanitized bottle
3. Pitch yeast isolates (I overpitched at ~5 billion cells)
4. Attach cap and shake vigorously for 15 seconds
5. Ferment at ambient temperature and vent cap every morning
6. After ~3 weeks, cold crash water bottles for 24-36 hours
7. Carefully transfer beer into a sanitized, CO2 purged, 500 ml plastic PET bottle (the amber soda kind)
8. Quick force carbonate using a Carbonator Cap (5 blasts of 40 psi CO2, shaken then degassed)

Below are the condensed tasting notes, provided in 10-word highlights for each beer. They are described in order of preference.

Foraged yeast #4 – damp hay, tropical fruit, warm clove, pear esters, pencil shavings

Foraged yeast #5 – ruby red grapefruit juice, barn hay, black pepper, dry, tart

Foraged yeast #6 – banana esters, cracked black pepper, orange zest, salty, dry, tart

Foraged yeast #7 – banana esters, cedar saw dust, cracked black pepper, dry finish

Foraged yeast #8 – runts banana flavor, wet cardboard, fruit cocktail, lavender, cracked pepper

Foraged yeast #9 – Italian biscotti, vanilla cake, canned beans, sour raspberry, sweet finish

Foraged yeast #10 – sweaty horse blanket, boiled cabbage, tart, dry finish, Fantôme-esque

Foraged yeast #11 – canned beans, lemony acetic flavor, wonder bread crust, sweet finish

Foraged yeast #12 – urine, floral perfume, purple pez candy, cherry cough syrup, plastic

Foraged yeast #13 – spicy phenols, tart pink lemonade flavor, cantaloupe rind, canned beans

Foraged yeast #14 – canned bean juice, burnt rubber, dentist/medicinal, simultaneously tart/sweet

Foraged yeast #15 – canned beans, dirty wet socks, boiled cabbage, sweaty, tart finish

Overall, none of these foraged yeast isolates were particularly appealing. #4 was the most palatable, particularly due to its fruitiness, however I still prefer my house yeast strain (foraged yeast #1). Interestingly, many of the isolates displayed aggressive banana esters (think textbook Hefeweizen) or offensive canned bean flavors, neither of which were particularly enjoyable. #10 was toward the bottom of the list, but was very reminiscent of some of the flavors commonly found in Fantôme offerings.

Not all experiments pan out, but these mini-fermentations were still interesting and informative. I am looking forward to the next round of foraged yeast isolate pilot batches later this month!