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Commercial gelatin is manufactured in modern factories
operated to the highest health and safety standards.
The raw material for gelatin manufacture is the naturally
occurring protein collagen, which is commercially sourced from the meat
industry. Each stage of the manufacturing process is rigorously controlled
in modern laboratories to ensure purity and quality. The process of
converting collagen into gelatin involves several cleansing and
purification steps and the end result is a pale yellow dry powder which is
a true foodstuff.
Gelatin contains:
- 84-90% protein
- 1-2% mineral salts
- 8-15% water
- It is free from additives and preservatives
Gelatin is a
high-grade protein
We cannot exist without protein, therefore edible gelatin -
a pure and easily digestible protein - is a particularly important part of
our diet. Other nutrients, such as fats and carbohydrates, can often
substitute each other in human metabolism, but protein can rarely, if ever,
be substituted and a regular intake is essential for our health and well
being.
Proteins are many and varied but are not all equal in their
nutritional value.
Proteins are
based on amino-acids
The building blocks of the various types of protein are
amino acids. Our body is capable of building the proteins it requires from
amino acids and to some extent is also capable of creating amino acids from
digestive fragments. This is not true of all amino acid types, which means
that we must eat ten essential amino acids regularly in our food. Edible
gelatin contains nine of these essential amino acids.
Gelatin
structures
Gelatin contains specific amounts of 18 different amino
acids (AA) which are joined together in sequences to form polypeptide
chains of ca. 1000 AA per chain, scientifically known as the primary
structure. Three of the polypeptide chains formed this way join together as
a left-hand spiral to give the secondary structure. In the tertiary
structure, the spiral winds and folds itself to a right-hand spiral (triple
helix). This results in a rod-shaped molecule, the so-called proto fibril.
Quality
characteristics
Several types of edible gelatin are available with varying characteristics
depending on the application and end product. Edible gelatin is a foodstuff
and must satisfy strict purity regulations. An important element in
determining the quality of gelatin is the firmness or strength of the set
gel. This is characterized by the "Bloom" value. The viscosity of
solution is also an important factor in manufacturing processes such as for
wine gums or "gummi bears" where gelatins with a low viscosity
are used to prevent "tailing" (molding deposits). The setting
point indicates the temperature at which a 10% aqueous gelatin solution
gels. For photographic, pharmaceutical, toiletries and technical
applications, other characteristics are important.
The best way to dissolve gelatin powder is to soak it in
cold water for a short time and then gently warm the water until the
gelatin has melted.
Other types such as leaf gelatin can be simply added to the
recipe and allowed to absorb liquid during cooling.
Instant gelatins are available as powders, which do not
need heating or "soaking" time. These are used for stabilizing
foods such as gateaux or desserts.
Test Procedures
Protein
hydrolysates: A very special type of gelatin
By means of a thermo-biochemical process, pure proteins
with no "gel strength" (Bloom value = 0) can be derived from
powdered gelatins. They dissolve easily in cold liquids and are completely
digestible. Due to their biological value and bland taste, they provide a
palatable source of protein in dietetic foods.
Thus they are used as:
- Carbohydrate-free carrier substances and fillers
for spray or fluid-bed dried products such as instant drinks and
flavorings.
- A substitute for carbohydrates in sweets and other
foods. Hydrolyzed gelatin solutions can replace more concentrated
solutions of carbohydrates and consequently reduce the calorific
value.
- A source of protein for the manufacture of sweets
and other foods with a high nutritional value.
- An emulsifier and whipping agent producing a
fine-pore, extremely stable foam in dairy products.
- A clarifier and fining agent in wines and juices.
Protein hydrolysates are also widely used in cosmetics and
toilet requisites as well as in the wide field of biotechnology, where
suitable protein sources are required as media for the growth of
micro-organisms.
Instant
gelatins
Available as powders which do not need heating or soaking
time, these are used for stabilizing foods such as gateaux and desserts.
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