4 Nano-additives for Food Industries
4.3 Nanostructures’ Food Additives
4.3.10 Pigmentation
The food colorant additives in food systems should be used only in obedience with the approved uses, specifications and restrictions by the FDA. Thus, there is limited applicable colorant compounds for food formulation. Since the color of the materi-als is a surface dependent characteristic, nanotechnology provides the color adjust-ment of these compounds. Thus, a various range of nano-sized color additives have been evaluated and manufactured. The colorant nanomaterials can also have either inorganic or organic nature. TiO2 nanoparticles is an inorganic, FDA approved food colorant compound, in less than 1% w/w concentration uses. The mixture of TiO2
with AL2O3 or SiO2, in less than 2% w/w, are also accepted for food formulations.
Candies, sweets and chewing gums can be formulated with TiO2 nanoparticles as a colorant ingredient (He and Hwang 2016; Martirosyan and Schneider 2014).
While the metal and metal oxide pigment nanoparticles are mostly used in food packaging formulations in order to provide market desirability, the organic pigment nanoparticles were added to food systems for either pigmentation or health promot-ing targets (He and Hwang 2016; Huang et al. 2010; Martins et al. 2016).
Anthocyanins, originated from various fruits and vegetables, can be used as either natural colorants or antioxidants. The uses of anthocyanins are preferred due to their intense and bright attractive colors and good water-solubility. However, their less bioavailability and restricted chemical stability against environmental conditions, such as light, oxygen, heat, pH, enzymes and occurrence of ascorbic acid etc. limits their commercial uses in various food formulations.
Nanoencapsulation of them can improve their stabilities considerably (Arroyo-Maya and McClements 2015; He et al. 2017). Table 4.2 shows some nanotechnol-ogy offered techniques for increasing the stability and bioavailability of anthocyanins.
Carotenoids, extracted from either plants or microbial cells, are also another set of natural colorants, which have various applications in food products’ pigmenta-tion. Like anthocyanins, they also have various health promoting benefits for human cells. Their antioxidant activity has been scientifically confirmed by various researchers. However, they are almost water-insoluble, unlike the anthocyanins.
Thus, incorporation of these colorants is challenging in food and beverage formula-tions. Moreover, the chemical structure of carotenoids are susceptible to heat, light and oxygen of the storage environment. The studies also reported limited bioavail-ability and cellular uptake for these compounds, as well. The nano-based delivery systems incorporated with carotenoids, can resolve most of the mentioned problems and increase their water solubilities, bioavailabilities, and stabilities (Anarjan and Tan 2013a; Martins et al. 2016; Tan and Nakajima 2005). Some of the research, which has been completed in this regard, is shown in Table 4.3.
The nanoencapsulation of phenolic compounds, curcumin, annatto, bixin and norbixin in order to increase their stabilities, water solubility and bioavailability have also been studied recently by several research groups. In some research the
4.3 Nanostructures’ Food Additives
effects of nano-sized colorants at various food systems, such as beverages and desserts etc., have also been investigated. Their results indicated that the nano-sized natural food colorants can offer more intense colors, more homogeneous systems and greater cellular uptake and, consequently, larger health promoting effects in incorporated foods (Amjadi et al. 2018; Anarjan and Tan 2013a; Ghayour et al.
2019; Wang et al. 2018).
Although some metal nanoparticles can stabilize the organic pigments, others would accelerate their degradation rates. Thus, in pigmentation of food products, the interaction of the colorant components should be considered (Martins et al. 2016).
Table 4.2 The nanotechnology offered techniques for improving the stability and bioavailability of anthocyanins
Pigment Delivery system
Encapsulation, stabilization and emulsifying
compounds Description References
Anthocyanin (originated from Açaí berry)
Anthocyanins- loaded nanoparticles
EUDRAGIT® L100, polyethylene glycol 2000 (PEG 2000), polysorbate 80
Increases bioavailability
Danay et al.
(2017)
Anthocyanin Electrostatic complexation
Whey protein isolate (WPI)
Beet pectin (BP)
D < 200 nm Increases thermal stability, decreases antioxidant activity, have similar color intensity
Arroyo-Maya and
McClements (2015)
Anthocyanin Anthocyanins loaded nanoparticles
Carboxymethyl chitosan (CMC), chitosan hydrochloride
D = 214.83 nm Increases gastrointestinal stability, used in model beverage system
He et al.
(2017)
Anthocyanin Complexation (intermolecular stacking between chondroitin sulfate and Anthocyanin)
Chondroitin sulfate D = 300 nm Increases pH stability, the system has a potential as a carrier for antioxidants or water-soluble drugs.
Jeong and Na (2012)
Anthocyanin Complexation Native whey protein;
denatured whey protein; citrus pectin;
and beet pectin (these biopolymers were used separately in complexation)
Increases the stability in model beverage systems for longer storage periods, heat denatured whey protein produced more stable product
Chung et al.
(2015)
59
Table 4.3 Some offered nano-based delivery systems for carotenoids for pigmentation uses
Pigment Delivery system
Encapsulation, stabilization and emulsifying
compounds Description References
β-carotene (and mixture of β-carotene, α-carotene and lutein)
Lipid core nanoparticles
Poly-ε- caprolactone sorbitan monostearate Triglycerides of the capric and caprylic acids polysorbate 80
D < 191 nm
The β-carotene retention in the mixed carotenoids lipid core nanoparticles were more than β-carotene ones The color intensities and stabilities of products remained constant over more than 100 days storage
da Silva et al.
(2016)
β-carotene Solid lipid nanoparticles and liquid lipid nanoparticles
Cocoa butter and/
or hydrogenated palm oil Tween 80
D < 200 nm
While the chemical and physical stabilities were increased for both systems, the liquid nanoparticles showed better efficiency in nanoencapsulation of the β-carotene
Qian et al.
(2013)
β-carotene Nanodispersion Modified OSA-starch
D = 200–300 nm Gastrointestinal stability of β-carotene was increased
Used in model beverage system
de Paz et al.
(2012)
β-carotene Nanodispersion Tween 20 D = 9–280 nm The stability and color intensity of β-carotene were increased
Silva et al.
(2011)
Lutein Nanodispersion Tween 80, short chain triglycerides/
or medium chain triglycerides/ or long chain triglycerides
D = 200 nm
Nanoemulsions could successfully encapsulated and protected the lutein
Surh et al.
(2017)
Lutein Nanoemulsions Whey protein isolate
D = 68 nm
The cellular uptake of lutein in nanoemulsions was increased
considerably
Teo et al.
(2017)
(continued) 4.3 Nanostructures’ Food Additives
The simultaneous extraction of natural pigmented from food manufacturing by- products, like tomato or grape skins, and their size reduction into nano-ranges, can also be efficient and economical for food-colorant uses (Anarjan and Jouyban 2017).
Biotechnology proposed the effective mass production of pigments, such as carotenoids, anthocyanins and betalains, using gene manipulation, in vitro cultur-ing and fermentation of various plant, animal and microbial cells. On the other side, the nanotechnology provides their delivery into the food systems used nano-sized
Table 4.3 (continued)
Pigment Delivery system
Encapsulation, stabilization and emulsifying
compounds Description References
Lutein Nanodispersions Tween 80 and sodium dodecyl sulfate sodium caseinate (individually or in combinations)
D = 66.20–125.25 nm The cellular uptake and color intensities were changed based on selected emulsifier
Tan et al.
(2016a, b)
Astaxanthin Nanodispersions Tween 20, sodium caseinate, Arabic gum (individually or in
combinations)
D = 98–157 nm The color intensity of samples were changed based on used stabilizers.
The three-component stabilizer could produce the most desired nanodispersions The cellular uptake of astaxanthin in prepared nanodispersions were increased considerably
Anarjan et al.
(2012)
Zeaxanthin Nanoparticles Nanoemulsions
Chia seed oil Cactus mucilage Tween 80
D = 184 nm The cactus cladode mucilage could protect zeaxanthin from structural degradation, significantly
de Campo et al.
(2018)
Lycopene Lipid core nanocapsules
Polymer (PCL), caprylic/capric triglycerides, sorbitan monostearate
D = 193 nm
The physical stability was improved However, the color increases for product happened during storage
dos Santos et al.
(2015)
Lycopene Nanodispersions Tween 20 Minimum D = 73 nm The physical stability of lycopene nanodispersions was increased. However, their lycopene content was decreased by a first order kinetic model
Anarjan and Jouyban (2017)
61
carriers in order to increase their stabilities, solubility and cellular uptake. Thus, nano- biotechnology presents considerable achievements in food pigmentation issues (Martins et al. 2016; Nickols-Richardson 2017).