10.2 Pulp and Paper Industry
Since early 2000, pulp and paper industry has seen an increased use of cellulase
significantly to overcome the aftermath of using the mechanical pulping process,
which leaves the pulps with high content of fines, bulk and stiffened (Mai et al.
2004). During the refining process, 20%–40% of energy may be saved, and the handsheet strength of the pulps also improved significantly (Singh et al. 2007). Crude
cellulases are mainly applied for the purpose of biomodifying the fiber properties
along with improving the ability of draining and beat in the paper mills after or
before beating of pulp (Dienes et al. 2004).
Pure cellulase containing only endoglucanase is able to reduce the pulp viscosity
during a low concentration hydrolysis (Pere et al. 1995). Additionally, pure cellulase
has shown the ability to boost the bleachability of kraft pulps made from softwood
with brightness compared to that obtained using xylanases (Singh et al. 2007). Pure
cellulase alone or combined with xylanases is being used for deinking the paper
wastes by releasing the ink from the fiber surface through the partial hydrolysis of
carbohydrate molecules (Kuhad et al. 2010a). The use of enzymes for deinking the
pulps reduces the use of alkali, improves the fiber brightness, increases pulp freeness
and cleanliness, improves strength properties, reduced fine particles in pulp,
simplifies the deinking process, changes the ink particle size distribution, and
reduces environmental pollution (Kuhad et al. 2010a; Stork and Puls 1996).
10.3 Food Processing Industry
There are several steps in extracting fruit and vegetable juices from their raw
materials: extraction, clarification, and stabilization. Cellulases play a very important
role in these steps for quality juices. Macerating enzymes consisting of crude
cellulases, xylanases, and pectinases are used to extract and clarify fruit and vegetable juices in order to enhance the yield of juices. Compared to pure cellulases, the
mixture of crude cellulases, xylanases, and pectinases known as macerating enzymes
enhances not only the yield but also the process performance without adding any
extra cost to the process. These macerating enzymes help to enhance the texture and
cloud stability of the purees and nectars of tropical fruits such as apricot, pear,
papaya, plum, peach, and mango by decreasing the viscosity (De Carvalho et al.
2008). Besides some of the properties of fruits and vegetables such as aroma, flavor,
and texture may be boosted using an infusion of enzymes such as pectinases and
β-glucosidases (Rai et al. 2007). In addition, the flavor, texture, aroma, and volatile
characteristics of vegetable and fruit may be modified by using a mixture of
β-glucosidases and pectinases (Karmakar and Ray 2011).
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M. S. H. K. Tushar and A. Dutta
Since early 2000, pulp and paper industry has seen an increased use of cellulase
significantly to overcome the aftermath of using the mechanical pulping process,
which leaves the pulps with high content of fines, bulk and stiffened (Mai et al.
2004). During the refining process, 20%–40% of energy may be saved, and the handsheet strength of the pulps also improved significantly (Singh et al. 2007). Crude
cellulases are mainly applied for the purpose of biomodifying the fiber properties
along with improving the ability of draining and beat in the paper mills after or
before beating of pulp (Dienes et al. 2004).
Pure cellulase containing only endoglucanase is able to reduce the pulp viscosity
during a low concentration hydrolysis (Pere et al. 1995). Additionally, pure cellulase
has shown the ability to boost the bleachability of kraft pulps made from softwood
with brightness compared to that obtained using xylanases (Singh et al. 2007). Pure
cellulase alone or combined with xylanases is being used for deinking the paper
wastes by releasing the ink from the fiber surface through the partial hydrolysis of
carbohydrate molecules (Kuhad et al. 2010a). The use of enzymes for deinking the
pulps reduces the use of alkali, improves the fiber brightness, increases pulp freeness
and cleanliness, improves strength properties, reduced fine particles in pulp,
simplifies the deinking process, changes the ink particle size distribution, and
reduces environmental pollution (Kuhad et al. 2010a; Stork and Puls 1996).
10.3 Food Processing Industry
There are several steps in extracting fruit and vegetable juices from their raw
materials: extraction, clarification, and stabilization. Cellulases play a very important
role in these steps for quality juices. Macerating enzymes consisting of crude
cellulases, xylanases, and pectinases are used to extract and clarify fruit and vegetable juices in order to enhance the yield of juices. Compared to pure cellulases, the
mixture of crude cellulases, xylanases, and pectinases known as macerating enzymes
enhances not only the yield but also the process performance without adding any
extra cost to the process. These macerating enzymes help to enhance the texture and
cloud stability of the purees and nectars of tropical fruits such as apricot, pear,
papaya, plum, peach, and mango by decreasing the viscosity (De Carvalho et al.
2008). Besides some of the properties of fruits and vegetables such as aroma, flavor,
and texture may be boosted using an infusion of enzymes such as pectinases and
β-glucosidases (Rai et al. 2007). In addition, the flavor, texture, aroma, and volatile
characteristics of vegetable and fruit may be modified by using a mixture of
β-glucosidases and pectinases (Karmakar and Ray 2011).
288
M. S. H. K. Tushar and A. Dutta