most intact gelatin molecules, produce the
strongest gels, and are the lightest in color;
higher temperatures damage more gelatin
chains and cause a yellow discoloration. The
extracts are then filtered, purified, their pH
adjusted to 5.5, evaporated, sterilized, and
dried into sheets or granules that are 85–90%
gelatin, 8–15% water, 1–2% salts, and 1%
glucose. Gelatin quality is sometimes
indicated by a “Bloom” number (named for
Oscar Bloom, inventor of the measuring
device), with high numbers (250) indicating
high gelling power.
Types of Gelatin Gelatin is sold in several
different forms. Granulated gelatin and sheet
gelatin are given an initial soaking in cold
water so that the solid gelatin network can
absorb moisture and dissolve readily when
warm liquid is added. If added to the warm
liquid directly, the outer layers of the solid
granules can become gluey and stick