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HEAD RETENTION
CHARACTERISTICS: Good head on the beer when
poured, not excessively large or small, Belgian lace on
glass, head remains for a several minutes. Very much
desired.
CAUSES: Small bubbles, dextrins, medium molecular
weight proteins, isohumulones from hops, nitrogen in
wort.
GOOD HEAD FROM PROCESS: Use of cara-pils; use
of crystal malt; use of malto-dextrin; all-malt beer; good
one hour rolling boil to extract the isohumulones from the
hops; use of wheat malt; adequate protein rest in the
mash to allow the proteolytic enzymes to break down the
large proteins into albumin and smaller fractions and
increase the nitrogen content; high-temperature
saccharification rest; racking to secondary to get beer off
sediment; lower temperature fermentation; bottle
conditioning.
POOR HEAD FROM PROCESS: Use of fully modified
malts; use of underkilned malts; not using a one-hour boil;
inadequate protein rest, low-temperature saccharification
rest; oversparging; yeast autolysis from long sediment
contact; excessive fusel oils; higher temperature
fermentation; excessive fatty acids; overboiling of wort;
insufficient or deteriorated hops; some types of finings.
POOR HEAD WHEN SERVING: Soap, detergent or oils
on glasses; lip balm, Chapstick or lipstick on lips