Technical data

1. General Information
1.1. Introduction
What is freeze drying (lyophilisation)?
Freeze drying means: Extraction of water from frozen material.
The drying process takes place by avoiding the liquid state through
sublimation, i.e. direct conversion from ice to vapor. This happens
under vacuum and the temperature in the product is normally less
than -10°C.
The aim of freeze drying is to obtain a readily water-soluble
product which has the same characteristics as the original product
after addition of water.
As the drying process takes place in the frozen state at very low
temperatures it is possible, for example, to dry proteins which will
not denature. Also most of the other chemical compounds will be
qualitatively and quantitatively unchanged.
Through freeze drying the product, mainly of biological origin -
such as tissues, tissue extracts, bacteria, vaccines and sera - is
transformed into a dry product. During this process enzymatic,
bacterial and chemical changes are largely avoided.
Freeze drying (lyophilisation) is the gentlest process for preserving
the biological properties of sensitive tissue and tissue components.
Lyophilisation is also the best method when drying inorganic
products – e.g. nanoscale dispersions – the particle surfaces of
which should remain unchanged.
Operating Manual Freeze Dryer ALPHA 1-4 LSC / ALPHA 2-4 LSC General Information • 1