Are the yeast related terms "top cropping" and "bottom cropping" Passé?

[Silver_Is_Money]

Since all yeasts are fully dispersed throughout the wort during active fermentation, and flock out thereafter, is it time to once and for all discontinue referring to them as "top cropping" or "bottom cropping", and get on with classifying them merely with regard to their suitability to meet a particular need?

 

[STMF]

Why? For us who do top crop our yeast there is a huge difference.

 

[Silver_Is_Money]

What happens when you top crop a "bottom cropping" yeast? Or when you bottom crop a "top cropping" yeast? Do you collect viable yeast for each case?

 

[STMF]

A true top cropping yeast flocculates and rises to the surface when fermentation is going on and start to end. When you crop that yeast you get very actvive and clean yeast, almost no proteins, hop trub or other unwanted stuff.

 

[Silver_Is_Money]

Per Wikipedia:

Decades ago, taxonomists reclassified S. carlsbergensis (uvarum) as a member of S. cerevisiae, noting that the only distinct difference between the two is metabolic. Lager strains of S. cerevisiae secrete an enzyme called melibiase, allowing them to hydrolyse melibiose, a disaccharide, into more fermentable monosaccharides. Top- and bottom-cropping and cold- and warm-fermenting distinctions are largely generalizations used by laypersons to communicate (this) to the general public.

https://en.wikipedia.org/wiki/Yeast#Beer

Some of today's most highly attenuating ale yeasts are likely also fermenting melibiose, thus blurring the distinction.

 

[Silver_Is_Money]

Common Answer #1: Ale is made with top-fermenting yeast, but lager is made with bottom-fermenting yeast.
This answer is misleading at best and simply not true. Observe an active fermentation for any length of time and you immediately notice that yeast activity is distributed throughout the liquid. As billions of yeast cells multiply and feed upon the available sugars, initially clear wort becomes rather cloudy. Bubbles rise to the top from all points in the fermentor, and the whole mass appears to churn violently. When fermentation is over, those yeast cells drop out of solution, and the beer becomes clear once again. Most yeast cells, ale and lager alike, flocculate and end up on the bottom of the fermentation vessel, at least to some degree.

https://beerandbrewing.com/VmsqtyQAADM1mZHK/article/what-is-the-difference-between-ale-and-lager

 

[STMF]

Are you talking about top/bottom-cropping or about top/bottom-fermenting?

 

[Silver_Is_Money]

Are you talking about top/bottom-cropping or about top/bottom-fermenting?

Right or wrong, both terms often seem to be used interchangeably, as if synonyms. The Wikipedia link mentions and dispels both as merely layperson generalizations. I am using them as synonyms. The restricted subject line space limited my choice here, but in the end that is of little consequence.

 

[STMF]

Well, top cropping and top fermenting does not mean the same. There are alot of terms that homebrewers use in one way, but they actually mean something else.

Yeast washing when they mean yeast rinsing
Lagering when they mean cold conditioning

to name just two.

 

[rhys333]

I only use top fermenting strains, and I've top-cropped many of them whether listed as "top-cropping strain" or not. I will say that the top-cropping strains are perfect for doing just that. As advertised.... dense yeast cake that takes off like a rocket when pitched into another batch.