Imperial Juice A38 yeast fermentation, possible contamination?

[The M]

New to the liquid yeast and starters so be kind Whipped up a 1L starter with Imperial A38 Juice 48h prior pitching. Now after two days of fermenting my brew buddy checked the status and said that the A38 had fermented from 1.058 (OG) to 1.018. The problem was that he said that when he tasted the sample he got peppery and smokey aroma from it. Could that be phenolic off-flavor? The starter were made on stir-plate in 20C for 48h and we got starter overflow, see the pic. The current beer which is fermenting is a pale ale. I can post the receipe if needed but I’m interested if we did something wrong with the starter? Batch size is 23L.

 

[RPh_Guy]

I agree, those flavors indicate likely contamination.

 

[The M]

What do you guys think in general about the starter pic I posted. Is that kind of overflow normal and is the starter still good to go after the overflow? The flask was covered with a tin foil which had been in Starsan.

 

[RPh_Guy]

Looks pretty normal.

Mine don't overflow because I use Foam Control (AKA FermCap-S) and a stir plate.

I also only make 500mL starters with yeast nutrient and only run them for 4 hours. It's called a vitality starter. ... Something to consider.

Cheers