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Kveik mixed cultures tend to be very flocculant, even though only about 48% of the individual strains are highly flocculant (it is thought that high flocculating strains help the lower flocculating strains to flocculate). Top-harvested kveik form a thick krausen and tends to float on top of liquid even when stored in the fridge, while bottom-harvested kveik tends to form a thin layer of krausen (see the [http://www.garshol.priv.no/download/farmhouse/kveik.html Farmhouse yeast registry] to see which kveik cultures are top vs bottom harvested; the listed harvesting method should be continued so as to continue to select for the correct strains). Harvested kveik can be stored in the refrigerator as a slurry, and survive 1-2 years (a starter should be made after about 6 months of cold storage). Attenuation ranges from 60-90% for single strains, but for mixed cultures, the attenuation is usually on the higher side <ref name="garshol_preiss_mbaa" />.
Kveik cultures make thinking about identifying individual strains within them difficult because the strains are closely related and there is often not a clear distinction between "strains", nor is there a clear definition of what makes a strain truly unique within the total population of strains that are found in a single kveik culture. Richard Preiss describes kveik cultures as being "heterogenous but related communities", meaning that there can be a lot of genetic overlap between subpopulations in a kveik culture. What exactly is meant by "strain" within the context of kveik cultures has not been defined, and so discussing individual strains of kveik is an inadequate way of discussing kveik <ref name="preiss_strains">[https://www.facebook.com/groups/MilkTheFunk/permalink/2593762590651939/?comment_id=2593908627304002&reply_comment_id=2594146987280166&comment_tracking=%7B%22tn%22%3A%22R%22%7D Richard Preiss and Lars Garshol. Milk The Funk post about the subtle differences in strains in some kveik cultures. 04/04/2019.]</ref>.
Kveik cultures have a wide range of fruity aromas, which is a result of above-threshold production of fatty acid esters, such as ethyl decanoate and ethyl caprylate <ref name="garshol_preiss_mbaa" />. Richard Preiss from [[Escarpment Laboratories]] shared his sensory notes after doing trial fermentations with various kveik strains/cultures. Fermentations were at 30°C in standard wort (1.050, 20IBU) with single strains, not the mixed cultures. 2/3 tasters were blind to the beers and order prior to tasting. This is a single data point on sensory information <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1336954522999425/?comment_id=1407412439286966&comment_tracking=%7B%22tn%22%3A%22R%22%7D Sensory data on kveik strains shared by Richard Preiss on MTF. 09/15/2016.]</ref>: