353
Encapsulation of Bioactive Compounds
Plants have antioxidant and antimicrobial properties due to the presence of many
bioactive phenolic compounds, such as anthocyanins, flavonols, flavan-3-ols, curcumin, proanthocyanidins, and phenolic acid derivatives, thus, may help in preventing some diseases such as urinary tract infections (Blumberg et al. 2013), stomach
ulcers and cancers (Pappas and Schaich 2009). However, at neutral pH and exposure
to oxygen, these phenolic compounds are chemically unstable (Betz et al. 2012) and
may deteriorate due to the oxidative degradation leading to the generation of free
radicals (Chen et al. 2016). Furthermore, there is development of unpleasant tastes
and off-odors in the fortified product and subsequently may result in a harmful
impact on shelf stability, sensory characteristics and consumer acceptability of the
product (Ariyarathna and Karunaratne 2015; Gomez-Mascaraque et al. 2017).
Therefore, in order to preserve the quality of bioactive compounds, or to enhance
their applicability to food, neutraceutical or biological formulations, encapsulation
is considered as a feasible alternative. Encapsulation has been regarded as an attractive method to entrap bioactive compounds within a polymer material for the purpose of protecting and delivering bioactive compounds at the right time and to a
targeted site (Ezhilarasi et al. 2013).
The demand for encapsulation systems continues to grow as the food industry
needs to preserve the benefits of active compounds and deliver them at specific
conditions. Encapsulation of bioactive compounds in food industry can be used to:
(1) preserve functional properties, (2) increase the stability of compounds with low
solubility in relevant (mostly aqueous) media, (3) mask undesirable flavours, (4)
improve health benefits of food products (i.e. development of functional foods), (5)
control the release of bioactive compounds at desired time and specific target, and
(6) enhance the bioavailability of bioactive compounds (Davidov-Pardo et al. 2015;
Gunasekaran et al. 2007; Huang et al. 2010; Kayitmazer et al. 2013; Livney 2010).
In food applications, encapsulating materials must be recognized as “generally
regarded as safe” (GRAS) materials (Robin and Sankhla 2013). Carbohydrate polymers, proteins, lipids, and other organic and inorganic materials are mostly used for
encapsulation in the food sector. Due to the desirable drying properties of carbohydrates and ability to form matrices, various materials such as starches, maltodextrins
and corn syrup are often used as microencapsulating agents (Gharsallaoui et al.
2007). However, carbohydrates usually have poor interfacial properties and must be
chemically modified to improve their surface activity (Kanakdande et al. 2007). In
recent years, an increasing interest in food protein based microencapsulation can be
attributed to their excellent emulsifying, gel-and film-formation properties (Chen
et al. 2006). Additionally, protein coatings are degradable by digestive enzymes,
thus can be used in developing food applications for controlled-core release (Chen
et al. 2006).
Advances in the Application of Food Proteins and Enzymes
Encapsulation of Bioactive Compounds
Plants have antioxidant and antimicrobial properties due to the presence of many
bioactive phenolic compounds, such as anthocyanins, flavonols, flavan-3-ols, curcumin, proanthocyanidins, and phenolic acid derivatives, thus, may help in preventing some diseases such as urinary tract infections (Blumberg et al. 2013), stomach
ulcers and cancers (Pappas and Schaich 2009). However, at neutral pH and exposure
to oxygen, these phenolic compounds are chemically unstable (Betz et al. 2012) and
may deteriorate due to the oxidative degradation leading to the generation of free
radicals (Chen et al. 2016). Furthermore, there is development of unpleasant tastes
and off-odors in the fortified product and subsequently may result in a harmful
impact on shelf stability, sensory characteristics and consumer acceptability of the
product (Ariyarathna and Karunaratne 2015; Gomez-Mascaraque et al. 2017).
Therefore, in order to preserve the quality of bioactive compounds, or to enhance
their applicability to food, neutraceutical or biological formulations, encapsulation
is considered as a feasible alternative. Encapsulation has been regarded as an attractive method to entrap bioactive compounds within a polymer material for the purpose of protecting and delivering bioactive compounds at the right time and to a
targeted site (Ezhilarasi et al. 2013).
The demand for encapsulation systems continues to grow as the food industry
needs to preserve the benefits of active compounds and deliver them at specific
conditions. Encapsulation of bioactive compounds in food industry can be used to:
(1) preserve functional properties, (2) increase the stability of compounds with low
solubility in relevant (mostly aqueous) media, (3) mask undesirable flavours, (4)
improve health benefits of food products (i.e. development of functional foods), (5)
control the release of bioactive compounds at desired time and specific target, and
(6) enhance the bioavailability of bioactive compounds (Davidov-Pardo et al. 2015;
Gunasekaran et al. 2007; Huang et al. 2010; Kayitmazer et al. 2013; Livney 2010).
In food applications, encapsulating materials must be recognized as “generally
regarded as safe” (GRAS) materials (Robin and Sankhla 2013). Carbohydrate polymers, proteins, lipids, and other organic and inorganic materials are mostly used for
encapsulation in the food sector. Due to the desirable drying properties of carbohydrates and ability to form matrices, various materials such as starches, maltodextrins
and corn syrup are often used as microencapsulating agents (Gharsallaoui et al.
2007). However, carbohydrates usually have poor interfacial properties and must be
chemically modified to improve their surface activity (Kanakdande et al. 2007). In
recent years, an increasing interest in food protein based microencapsulation can be
attributed to their excellent emulsifying, gel-and film-formation properties (Chen
et al. 2006). Additionally, protein coatings are degradable by digestive enzymes,
thus can be used in developing food applications for controlled-core release (Chen
et al. 2006).
Advances in the Application of Food Proteins and Enzymes