Biomedical Engineering Reference
In-Depth Information
in degumming of vegetable oil is also known. In vegetable oil processing
the majority of the phospholipids is removed by washing the oil with
water. In this water degumming phase, only the rapidly hydratable
phospholipids are readily removed. The non-hydratable phospholipds,
phosphatidylethanolamine and phosphatidic acid, cannot be removed with
water, unless they are hydrolysed by phospholipase or with citric acid. The
lower carbon footprint of the phospholipase treatment gains industrial
interest. Furthermore, phospholipase is used for lecithin modifi cation, in
oil degumming, mayonnaise production, cake production, egg processing
and production of structured phospholipids (Hayes 2004, Dutilh and Groger
1981). The phospho- and galactolipases of fungal origin are derived from
Fusarium
species, such as
F. oxysporum, F. heterosporum, F. venenatum
, but
also
A. tubigensis.
Table 2.
Major fungal lipases in food applications.
Enzyme type
EC
number
Organism of origin
Applications
triacylglycerollipase
3.1.1.3
Aspergillus niger, Rhizopus
oryzae, Rhizomucor miehei,
Thermomyces lanuginosus,
Penicillium
sp.
bread, cheese,
transesterifi cation of
lipids
Aspergillus tubigensis,
Fusarium
sp.
phospholipase A1
3.1.1.32
bread, cake, cheese, oil
degumming, mayonaise,
egg processing
phospho-/
galactolipase
3.1.1.32/
3.1.1.26
Aspergillus tubigensis,
Fusarium oxysporum
Bread
Proteases
Proteases represent one of the three largest groups of industrial enzymes
others being the amylases and lipases. Proteases are enzymes that split
proteins and protein fractions via hydrolysis, i.e. the addition of water
across peptide bonds (
Fig. 3).
The hydrolysis of peptide bonds by proteases
is termed proteolysis. The products of proteolysis are peptides and amino
acids.
Commercial proteases are derived from animal tissues, plant cells and
microbial cells via fermentation. Plant and animal derived proteases are
used for a long time, without knowing its actual presence and working
mechanism, in traditional food processing such as cheese making with
calf rennet. However, plant and animal derived proteases are often crude
preparations consisting of more than one protease and several other
enzymes with non-proteolytic activities. Nowadays microbial fermentation
derived proteases are becoming the dominant source of proteases applied
