and pectins), lipids (waxes, acylglycerols, and fatty acids),
and proteins. Flours with high fiber content that are obtained
from vegetable residues can be used in bioplastics, resulting
in several benefits for these products, e.g., increasing the
mechanical properties and thermal stability, and decreasing
the water adsorption (Crizel et al. 2018).
The increase in the proportion of flour byproducts of
sprouts provided an increase in opacity, but did not interfere
in the grammage or acid solubility values. Biofilms with
greater weights, also offer greater mechanical resistances,
i.e., a greater resistance to mechanical deformations
(Almeida et al. 2013). Biodegradable films with sprout flour
byproducts are also suitable for packaging or coating products with low levels of moisture and acidity, in addition to
foods with high-fat contents. In addition, the appearance of
the bioplastic illustrates a sufficient adaptation to market
trends for alternative and biodegradable packaging (Silva
et al. 2020).
The solvability of chitosan-based biofilms in aqua is a
fundamental feature, and water resistance is a sine qua non
condition for food packaging biofilms (Pavoni et al. 2019).
Piyada et al. (2013) observed that the large water resistance
of the Ch-ge-Q film (chitosan-gelatin-quercetin), which
contains gelatinous chitosan, was maybe because of the
relation and miscibility of the amino group inherent in the
gelatin and chitosan with the quercetin phenolic component.
For the food packing biofilms, water vapor permeability
is an essential factor, and it is utilized to assess the biofilm
ability to decrease the humidity transport involving the food
and the ambient surrounding the packing (Aguirre-Loredo
and Velázquez 2016).
Food can easily deteriorate in environments with high
moisture contents if it is not sufficiently stored and/or protected. The increase in moisture can lead to undesirable
effects, e.g., sensory alteration, nutrients loss, and the
appearance of microorganisms that facilitate the degradation
of food (Reis and Schmiele 2019).
In 2020, (Yadav et al. 2020) studied the structural characteristics
of
chitosan
and
gelatin,
including
quercetin-starch, and they discovered characteristics of the
biofilms with a base on chitosan-gelatine that contained
complexes based on quercetin-starch. In addition, they found
that to keep the fresh food, the PWV range must be kept as
low as possible. This PVW behavior verified in the Ch-ge-Q
biofilm is related with the attendance of hydroxyl and amino
species in the chitosan skeletons that can supply linkage sites
for water atoms (Souza et al. 2017). The biofilm infiltration
of water vapor occurs through 2 (two) ways: adsorption and
desorption. Because of the occurrence of biofilm hydrophilic
character, the water vapor was simply adsorbed, and the
dispersion stage was substantially enhanced (Souza et al.
2017).
3.2.2 Mechanical Properties
Tensile Strength and the Young’s Modulus
The tensile resistance of the chitosan-based biofilms is
straight associated with the molecular mass and deacetylation grade (Mujtaba et al. 2019). The dehydration temperature and relative air moisture too make an important function
in the mechanical and hurdle features of chitosan-based
biofilms (Vlacha et al. 2016). According to Pavoni et al.
(2019), the tensile strength of the chitosan biofilms created
with acetic acid increases when stored at ambient temperature (%23 °C). This increase depends on the tensile strength
time, and it can be described means of the conformational
changes in the chitosan atoms and by reducing the free
polymer volume (Liu et al. 2017). A recent study (Darbasi
et al. 2017) claimed that the tensile strength and stretching at
breakdown increased for chitosan-based biofilms, including
propolis essence. These chitosan-based biofilms (Ch-ge-Q)
can be used to rise the food product conservation times.
The rice straw nanofibers demonstrated the greatest
strength with a Young modulus of approximately 1200 MPa
(Siripatrawan and Vitchayakitti 2016). This improvement in
the Young modulus was associated with the fiber nature and
hard linkages formed among the chitosan and charges used
in the experiments (maximum charge of 50 kN), ensuring an
efficient charge transfer from the matrix to reinforcement
fiber (Elhussieny et al. 2020). Hence, the chitosan reinforced
with cellulose and/or nanocellulose extracted from rice straw
residues is a favorable solution to replace plastic bags for
food packaging (Welden 2020).
3.3 Biological Properties
The decay test is an important indicator of the biodegradability of composite products. Dehghan et al. (2019) verified
that the bamboo flour amount exerted a significant effect on
the degradation of the composite manufactured after 60 days
of incubation. In general, the lowest weight loss achieved for
all three types of fungi (G. trabeum, T. versicolor, and C.
globosum) was obtained for the pure polymer. Therefore, the
mixed composite was biodegradable when exposed to wood
decomposition fungi, while the high-density pure polylactic
acid composite was completely resistant to deterioration
through microbiological action Dehghan et al. (2019).
Chitosan is a natural biopolymer, which exhibits sufficient antimicrobial action contra several types of living
organisms, e.g., gram-positive and gram-negative bacteria,
filamentary fungus, and yeasts (Kumar et al. 2020).
Hosseinnejad and Jafari (2016) demonstrated that the
antimicrobial chitosan properties and mechanisms involved
remain unclear, but the most acceptable ones include the
288
A. A. Santana et al.
and proteins. Flours with high fiber content that are obtained
from vegetable residues can be used in bioplastics, resulting
in several benefits for these products, e.g., increasing the
mechanical properties and thermal stability, and decreasing
the water adsorption (Crizel et al. 2018).
The increase in the proportion of flour byproducts of
sprouts provided an increase in opacity, but did not interfere
in the grammage or acid solubility values. Biofilms with
greater weights, also offer greater mechanical resistances,
i.e., a greater resistance to mechanical deformations
(Almeida et al. 2013). Biodegradable films with sprout flour
byproducts are also suitable for packaging or coating products with low levels of moisture and acidity, in addition to
foods with high-fat contents. In addition, the appearance of
the bioplastic illustrates a sufficient adaptation to market
trends for alternative and biodegradable packaging (Silva
et al. 2020).
The solvability of chitosan-based biofilms in aqua is a
fundamental feature, and water resistance is a sine qua non
condition for food packaging biofilms (Pavoni et al. 2019).
Piyada et al. (2013) observed that the large water resistance
of the Ch-ge-Q film (chitosan-gelatin-quercetin), which
contains gelatinous chitosan, was maybe because of the
relation and miscibility of the amino group inherent in the
gelatin and chitosan with the quercetin phenolic component.
For the food packing biofilms, water vapor permeability
is an essential factor, and it is utilized to assess the biofilm
ability to decrease the humidity transport involving the food
and the ambient surrounding the packing (Aguirre-Loredo
and Velázquez 2016).
Food can easily deteriorate in environments with high
moisture contents if it is not sufficiently stored and/or protected. The increase in moisture can lead to undesirable
effects, e.g., sensory alteration, nutrients loss, and the
appearance of microorganisms that facilitate the degradation
of food (Reis and Schmiele 2019).
In 2020, (Yadav et al. 2020) studied the structural characteristics
of
chitosan
and
gelatin,
including
quercetin-starch, and they discovered characteristics of the
biofilms with a base on chitosan-gelatine that contained
complexes based on quercetin-starch. In addition, they found
that to keep the fresh food, the PWV range must be kept as
low as possible. This PVW behavior verified in the Ch-ge-Q
biofilm is related with the attendance of hydroxyl and amino
species in the chitosan skeletons that can supply linkage sites
for water atoms (Souza et al. 2017). The biofilm infiltration
of water vapor occurs through 2 (two) ways: adsorption and
desorption. Because of the occurrence of biofilm hydrophilic
character, the water vapor was simply adsorbed, and the
dispersion stage was substantially enhanced (Souza et al.
2017).
3.2.2 Mechanical Properties
Tensile Strength and the Young’s Modulus
The tensile resistance of the chitosan-based biofilms is
straight associated with the molecular mass and deacetylation grade (Mujtaba et al. 2019). The dehydration temperature and relative air moisture too make an important function
in the mechanical and hurdle features of chitosan-based
biofilms (Vlacha et al. 2016). According to Pavoni et al.
(2019), the tensile strength of the chitosan biofilms created
with acetic acid increases when stored at ambient temperature (%23 °C). This increase depends on the tensile strength
time, and it can be described means of the conformational
changes in the chitosan atoms and by reducing the free
polymer volume (Liu et al. 2017). A recent study (Darbasi
et al. 2017) claimed that the tensile strength and stretching at
breakdown increased for chitosan-based biofilms, including
propolis essence. These chitosan-based biofilms (Ch-ge-Q)
can be used to rise the food product conservation times.
The rice straw nanofibers demonstrated the greatest
strength with a Young modulus of approximately 1200 MPa
(Siripatrawan and Vitchayakitti 2016). This improvement in
the Young modulus was associated with the fiber nature and
hard linkages formed among the chitosan and charges used
in the experiments (maximum charge of 50 kN), ensuring an
efficient charge transfer from the matrix to reinforcement
fiber (Elhussieny et al. 2020). Hence, the chitosan reinforced
with cellulose and/or nanocellulose extracted from rice straw
residues is a favorable solution to replace plastic bags for
food packaging (Welden 2020).
3.3 Biological Properties
The decay test is an important indicator of the biodegradability of composite products. Dehghan et al. (2019) verified
that the bamboo flour amount exerted a significant effect on
the degradation of the composite manufactured after 60 days
of incubation. In general, the lowest weight loss achieved for
all three types of fungi (G. trabeum, T. versicolor, and C.
globosum) was obtained for the pure polymer. Therefore, the
mixed composite was biodegradable when exposed to wood
decomposition fungi, while the high-density pure polylactic
acid composite was completely resistant to deterioration
through microbiological action Dehghan et al. (2019).
Chitosan is a natural biopolymer, which exhibits sufficient antimicrobial action contra several types of living
organisms, e.g., gram-positive and gram-negative bacteria,
filamentary fungus, and yeasts (Kumar et al. 2020).
Hosseinnejad and Jafari (2016) demonstrated that the
antimicrobial chitosan properties and mechanisms involved
remain unclear, but the most acceptable ones include the
288
A. A. Santana et al.