Changes

'''Yeast flocculation''' typically refers to the clumping together of brewing [[yeast]] once the [[sugar]] in a beer brew has been converted into [[alcohol]]. In the case of ale yeast [[Saccharomyces cerevisiae]] the yeast floats to the top of an open tank, whereas with lager yeast [[Saccharomyces pastorianus]] the yeast will sink to the bottom of the tank.

'''Yeast flocculation''' typically refers to the clumping together of brewing [[yeast]] once the [[sugar]] in a beer brew has been converted into [[alcohol]]. In the case of ale yeast [[Saccharomyces cerevisiae]] the yeast floats to the top of an open tank, whereas with lager yeast [[Saccharomyces pastorianus]] the yeast will sink to the bottom of the tank.

Cell aggregation occurs throughout microbiology, in [[bacteria]], [[filamentous algae]], [[fungi]] and [[yeast]] (Lewin, 1984; Stratford, 1992). Yeast are capable of forming three aggregates; mating aggregates, for DNA exchange; chain formation, for development and differentiation; and flocs as a survival strategy in adverse conditions (Calleja, 1987). Brewing strains are [[polyploid]] so mating aggregates do not occur. Therefore only chain formation and flocculation are of relevance to the brewing industry.

[[Cell aggregation]] occurs throughout [[microbiology]], in [[bacteria]], [[filamentous algae]], [[fungi]] and [[yeast]] (Lewin, 1984; Stratford, 1992). Yeast are capable of forming three aggregates; mating aggregates, for DNA exchange; chain formation, for development and differentiation; and flocs as a survival strategy in adverse conditions (Calleja, 1987). Brewing strains are [[polyploid]] so mating aggregates do not occur. Therefore only chain formation and flocculation are of relevance to the brewing industry.

Flocculation is distinct from [[agglomeration]] (‘grit’ formation), which is irreversible and most commonly in bakers yeast strains of fail to separate when resuspended (Guinard and Lewis, 1993). Agglomeration only occurs following the pressing and rehydration of yeast cakes and both flocculent and non-flocculent yeast strains have been shown to demonstrate agglomeration (Guinard and Lewis, 1993). It is also distinct from the formation of biofilms, which occur on a solid substrate.

Flocculation is distinct from [[agglomeration]] (‘grit’ formation), which is irreversible and most commonly in bakers yeast strains of fail to separate when resuspended (Guinard and Lewis, 1993). Agglomeration only occurs following the pressing and rehydration of yeast cakes and both flocculent and non-flocculent yeast strains have been shown to demonstrate agglomeration (Guinard and Lewis, 1993). It is also distinct from the formation of biofilms, which occur on a solid substrate.