Ultrasound-assisted extraction (UAE) can considerably aid the extraction operation by generating “cavitation effects” to break down the tissue or cell [48]; thus, the mass transfer between the solution and the cell is remarkably amended leading to a conservation of time and energy [49]. Utilizing both solvents and acoustic energy, the UAE method targets compounds from a variety of plant matrices. Besides, ultrasound irradiation has a significant impact on the diffusions that happen through the cell walls and washing out (rinsing) the contents of the cell after the walls are broken [50]. Further, the variables of time, temperature, intensity, and frequency of ultrasound can directly influence extraction efficiency/yield. Effective extraction also depends on the characteristics of the sample, such as its moisture content and particle size, as well as the types of solvents used [51]. Sonic cavitation is the main operating mechanism in the UAE, which is capable of generating a series of compression waves in the liquid solvent molecules, leading to the creation of bubbles due to changes in temperature and pressure. Many systems have been found to be implemented in the UAE as a whole. Separation resulting from collisions between particles and ultrasonic waves, results in a reduction in particle size and thus increases mass transfer [52]. Espada-Bellido et al. [53] used ultrasound to extract anthocyanins and phenolic compounds from the pulp of the mulberry (Morus nigra). A few extraction factors, including methanol focus (half 100%), temperature (10°–70°C), ultrasound plentifulness (30–70%), cycle (0.2–0.7 s), dissolvable pH (3–7) and dissolvable strong proportion [10:1.5 to 20:1.5, (v:v)] were enhanced to bring about the great extraction efficiency. For the extraction of anthocyanins and phenolic compounds, the parameters of most influence include extraction temperature and concentration of solvent. In addition, the progress of generating various bioactive components would favor UAE conditions. For instance, anthocyanins require a methanol concentration of 76%, a solvent-solid ratio of 12:1.5 (v:v), an extraction temperature of 48°C, a cycle time of 0.7 s, and a 70% ultrasound amplitude at pH = 3. Phenolic compounds require a methanol concentration of 61%, a solvent-solid ratio of 11:1.5 (v:v), an extraction temperature of 64°C, a cycle time of 0.7 s, and a 70% ultrasound amplitude at pH = 7. Under the UAE ideal circumstances, the augmented extraction yields of absolute anthocyanins and total phenolic compounds were 149.95 μg/g and 1,214.03 μg/g, separately. Bonfigli et al. [54] compared ultrasound extraction of grape pomace anthocyanins to conventional extraction. Water and 50% ET were combined. Both methods were evaluated, and it was found that UAE increased the mass transfer rate during the washing stage of anthocyanin extraction. In contrast, the UAE method extracts 90% of anthocyanins at the same time while conventional solvent extraction (CSE) extracts 80% of them in the first 600 s. The structure of materials, as well as their physical and chemical characteristics, are altered by ultrasound waves, which produce cavities within the cell wall(s). Consequently, releasing bioactive compounds, and increasing mass transfer should occur while decreasing extraction over time. As extraction yield increased with temperature, the role of UAE in generating polyphenols has been the subject of debate by many researchers. Numerously, ultrasound would enhance the extraction of bioactive compounds like polyphenols from various plant by-products [55–58].

The electromagnetic waves that make up microwaves typically operate at a frequency of 2.45 GHz. The microwave-assisted extraction (MAE) method incorporates the heating effect of microwaves, making the extraction temperature higher and resulting in faster transfer rates [59]. Microwaves can also cause direct/massive heating of the solvent body and sample matrix due to microwave penetration into certain materials to a certain depth and their interaction with polar properties [60]. When compared to traditional extraction techniques, MAE can speed up the extraction process [61–63]. In recent years, there has been ample progress in numerous studies about the MAE of antioxidants from plant materials [64–67]. Considering the thermal effect of microwave irradiation, MAE appears unable to adapt the extraction of thermally labile antioxidants, which could reduce the extraction yield. Additionally, MAE can only be used with extraction solvents that absorb microwaves. The treatment time, temperature, and microwave energy all have an impact on MAE efficiency. Hayat et al. [68] described the effects of microwave energy and treatment time on the extraction of phenolic compounds from citrus mandarin peel and pomace. While the bound phenolic content decreased, the concentration of free phenolics in the extracts significantly increased with microwave energy/time. By the microwave treatments, some bound phenolics in the tissue matrix appear cleaved and released, allowing their free-form presence in the extracts. However, some flavonol compounds would degrade when the treatment time progressed with microwave energy. More so, the few benefits of MAE might corroborate ordinary extraction strategies, for example, higher extraction yield, less dissolvable utilization, and more limited extraction time [69, 70]. Further, MAE has merits over traditional maceration or potentially strong/fluid extraction, for example, a substantial decrease of extraction time while acquiring comparative or higher extraction proficiency. The deterioration of cell layers in plant materials by pulse electric field (PEF) innovation, which was proposed as a non-warm extraction technique, could improve the extraction yield of bioactive particles from plants. The pulsed electric fields method uses short pulses with a high electric field intensity (0.1–50 kV/cm) at room temperature [71].

In PEF, a material situated between two cathodes reflects the areas of strength for a field. Pore formation can occur if the membrane is challenged with sufficient stress from the electrical field. Depending on the PEF treatment conditions, such as electric field strength, number of pulses, and pulse duration, pore formation can be reversible or irreversible. Cell permeability is increased when pores form [72]. Other workers, like Zderic and Zondervan [73] showed the addition of temperature would not surpass 10°C during the extraction of polyphenol from new tea leaves utilizing PEF. Corrales et al. [74] showed that non-thermal conditions provided by pulsed electric field processing increased slightly the temperature. When PEF served as a pre-treatment at 25°C/min alongside conventional thermal extraction at 70°C/h, the concentration of anthocyanins in the red grape by-product showed a 60% increase. The extraction of 10% more polyphenols was shown from white grape skins treated with PEF at 20°C [75]. Although industrial-scale equipment is still in improvement and the procedure does not utilize solid products, PEF appears to be a potential method for pre-treatment in the extraction of polyphenols from by-products [76]. Besides extraction of antioxidants from food and medicinal plants, like Norway spruce bark’s polyphenols [77], the PEF technology has the capacity to improve extraction efficiency, for instance, anthocyanin from by-products of blueberry processing [78]; ellagic acid and quercetin from the juice of Emblica officinalis [79]; betanins from beetroot (Beta vulgaris L.) [80]; carotenoids from date fruit (Phoenix dactylifera L. Sukkari) [81]; carotenoids from tomato (Solanum lycopersicon) [82]; and chlorophylls from custard apple (Annona squamosa) leaves [83]. Solute extraction relies heavily on the strength of the electric field. Ozkan et al. [84] examined the effects of high-pressure processing (HPP: 200 MPa, 400 MPa, and 600 MPa at 5/15 min) and PEF (3 kV/cm, 5 kJ/kg, 10 kJ/kg, and 15 kJ/kg) treatments on the antioxidant capacities and total phenolic, total flavonoid, and total anthocyanin content of cranberry purees. Expanded pressure levels and longer length times in HPP, and expanded explicit energy input values in PEF are not entirely set in stone to prompt higher absolute phenolic and complete flavonoid levels. In any case, the PEF treatment performed at 15 kJ/kg at a specific energy input level yielded greater qualities compared to the crude puree although a slight, but not statistically significant trend occurred. The considerable phenolic compound in cranberry bush fruit, chlorogenic acid, increased in both the HPP and PEF treatments by 6–7% and 5.6–11%, respectively. Although HPP did not significantly alter antioxidant volume, PEF treatment at 15 kJ/kg significantly increased antioxidant volume, which may be attributable to the samples’ greater amounts of phenolics and flavonoids. It was hypothesized that the improved extractability of phenolics as a result of progressed cell penetrability and the potential inactivation of the endogenous deteriorative enzymes were the causes of the slight increments that were observed in HPP-treated and PEF-treated samples.

Pressurized liquid extraction (PLE) is another name for accelerated solvent extraction (ASE), and both employ solvents at higher temperatures/pressures to make for a more effective/sped-up extraction process. PLE may offer a more efficient alternative to solvent-based methods for the extraction of anthocyanin and other bioactive compounds from plant sources. Specifically, the liquid solvent is subjected to high temperatures and pressures of 4 MPa to 20 MPa in the PLE method. Even when the solvent is heated beyond its boiling point, this pressure maintains its liquid state [85, 86]. In a pressurized environment, pores allow the solvent to diffuse into plant tissues and come into contact with the desired molecules, increasing extraction recovery [87]. In a study conducted by Truong et al. [88], the researchers investigated the extraction of anthocyanins from different varieties of purple-shed sweet potatoes using PLE. To extract anthocyanins, acidified methanol was used on freeze-dried powder obtained from purple-eyed sweet potato. The PLE condition included the use of acetic acid and methanol with a water mixture of 7%:75%:18% (v:v:v). The highest recovery of anthocyanins was obtained at temperatures ranging from 80°C to 120°C using this extraction condition. On a dry and weight basis, the anthocyanin contents of 335 genotypes ranged from 0–663 mg/100 g and 0–210 mg/100 g, respectively. Blackberry, jabuticaba, blueberry, and black bean have all been successfully recovered using PLE [89–92]. Nevertheless, anthocyanin degradation may occur during the extraction process due to the high temperatures of the process. However, the absence of oxygen limits the occurrence of oxidation reactions during PLE because it is carried out in a closed system. Garcia-Mendoza et al. [93] utilized four distinct solvents which were assessed in PLE: 99.5% ET; ET and water (1:1, v/v) in an acidified mixture with a pH of 2 (EW), distilled water (DW), water with an acidic pH of 2 (AW). While pressure (10 MPa) and flow rate (1.5 mL/min) remained constant, three distinct temperatures (40°C, 60°C, and 80°C) were examined. By increasing their diffusion and solubility in various solvents, the temperature rises in PLE enhanced the recovery of phenolic compounds. Low extraction yields were the consequence of anthocyanins being thermally broken down at temperatures higher than 40°C. There were significant correlations between the total phenolic content (TPC) and the PLE extracts.

The application of HVED has improved the extraction of soluble materials from water. Vegetable materials such as sesame seeds, grape stems, sugar beet pulp, and peanut shells have been used to apply this technology [94–97]. When a high voltage is applied between two electrodes, the electrons are accelerated and gain sufficient energy to excite molecules of water. Following that, a streamer, or electron avalanche, is created. If a sufficient electric field is applied, the streamer travels from the positive electrode to the negative one. The electrical breakup occurs when one of the streamers reaches the negative electrode. High-amplitude pressure shock waves, bubble cavitation, and liquid turbulence are all produced by electrical breakdown. Particle fragmentation and damage to the cell structure are the results of these phenomena that speed up the process of extracting compounds from within cells. HVED is a green extraction method because it can increase the rate of compounds extracted in a shorter amount of time and with less energy, temperature, and input [96]. Boussetta and Vorobiev [98] investigated the effects of HVED on grape (Vitis vinifera L.) residue fluid polyphenol extraction at mild temperatures (20°–60°C). The results showed that in comparison to the yield of 30% obtained after 240 min without HVED extraction, 70% of the extracted solutes from fresh grape residues after 40 min of HVED extraction were more than twice as huge. Removing HVED after 1 h also increased the polyphenol yield (Yield_polyphenols = 0.44% ± 0.07%) in comparison to the extraction without HVED after 4 h (Yield_polyphenols = 0.26% ± 0.06%). Nevertheless, there may be side effects to this approach. According to Boussetta et al. [99], using HVED can result in the production of extremely minute fragments, which can make the subsequent step of separating liquid from solid more challenging.

Due to the low extraction conditions and minimal environmental impact, enzyme-assisted extraction (EAE) is a possible green extraction technique [100], which favors compounds’ release being trapped, and dependent on enzymes’ capacity to either degrade or disorder complex substances within the cell wall. The basic elements impacting extraction proficiency and yield are the categories of enzymes, incubation temperature, concentration, incubation time, particle size, pH, and liquid-to-solid ratio [101]. The extraction efficiency is affected by the concentration of the various enzymes that degrade various substrates. According to Garg et al. [102], pectinases are a group of enzymes that catalyze the breakdown of pectic polymers in plant cell walls. Cellulases depolymerize cellulose into fermentable sugars [103], and tannase hydrolyzes ester and depside bonds in hydrolysable tannins to produce glucose and GA [104]. As a result, it is anticipated that each enzyme action will result in a selective enhancement of distinct phenols in the extract. Additionally, different enzymes have different pH requirements for enzymatic hydrolysis. The decomposing of some bioactive components, like anthocyanin, is influenced by the pH as well as the activity of enzymes. In addition, during processing, the temperature, incubation period, and liquid-to-solid ratio should all be taken into account. Thus, the optimal extraction parameters for different plant materials and enzymes vary. In one study, pectinase, α-amylase, protease, and β-glycosidase were combined to extract phenolic compounds from watermelon skin using an EAE technique. Four factors were investigated in order to obtain the maximum polyphenol yield: pH (6–9), temperature (25°–75°C), treatment time (30–90 min), and enzyme concentration (0–6.5%). Under optimal conditions (2.24% enzyme concentration, 51.8°C, pH = 6.58, 3 min), optimized EAE produced levels of 173.7 mg GA equivalents (GAE)/g fresh weight (FW, total phenolics), 279.96 mg trolox equivalents (TE)/g FW [trolox equivalent antioxidant capacity (TEAC)], and 112.27 mg/mL [2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging ability, half maximal inhibitory concentration (IC₅₀)] that were three times greater than those produced by CSE [105]. Possibly, the response surface methodology method would have the capacity to maximize enzyme-aided phenolics and extraction yield. Indeed, optimizing the simultaneous enzymatic treatment could improve extraction of antioxidant extraction by above 60% and its recovery by about 80%. Indeed, besides the distinct enzyme effects in the extract, while gallic and syringic acid phenolic extract is enhanced by tannase, it is enriched in p-coumaric acid and malvidin-3-O-glucoside by cellulose [106]. Depending on the phenolic compound, the combination of the enzymes can result in either positive or negative effects. When it is necessary to selectively enrich particular compounds, this fact must be taken into account. For further increasing extraction efficiency, there is another technique known as EAE linked with ultrasound, microwave, alongside HHP extraction. For extracting tricin, a flavonoid, from rice hull, there is an enzymatic hydrolysis and HHP method [107].

A fluid becomes a highly critical fluid when it is heated to a pressure and temperature higher than its critical point. Under these circumstances, the fluid’s characteristics lie halfway between those of a gas and a liquid. SF extraction (SFE) has gained a lot of traction in recent years as an environmentally friendly and sustainable technology. To extract specific components from several matrices, SFE makes use of the exceptional physicochemical properties of SF. There are basically two major steps in SFE: the supercritical solvent is used to first extract the plant material’s soluble compounds, and then these compounds are separated from the supercritical solvent by quickly decreasing pressure, increasing temperature, or both [108]. SFE of caffeic acid derivatives, phenolic compounds, etc., obtained from food and medicinal plants have been reported [109–115]. Talmaciu et al. [116] investigated the effects of SFE, UAE, and traditional ethanolic extraction on the polyphenol extraction process from spruce bark, a waste product of the forestry industry. SFE was performed at 1,200 psi for 60 min with pure CO₂ and 70% ET as a co-solvent. UAE was performed using 70% ET in an ultrasonic bath at 40°C for 60 min. Ethanolic extraction was achieved using 70% ET in an oven for 13 days at 40°C. Compared to UAE (33.48 mg GAE/g) and ethanolic extraction (14.38 mg GAE/g), the yield of total phenolic compounds from SFE was significantly higher (122.41 mg GAE/g). Furthermore, high-performance liquid chromatography (HPLC) analysis of compounds revealed that SFE extracts had a higher extraction yield of phenolic compounds than UAE extracts, including sinapic acid (35.05 mg/L), p-coumaric acid (260.41 mg/L), and catechin (171.18 mg/L).

Extraction with hot water and pressure has lately emerged as a useful alternative to traditional methods. PLE is typically referred to as subcritical water extraction (SWE), superheated water extraction, pressurized hot water extraction, or pressurized low-polarity water extraction, when only water is utilized as a solvent [117]. In order to keep water in a liquid state, SWE is performed with hot water (between 100°C and 374°C, the water critical temperature) and high pressure (typically between 10 bar and 60 bar). Depending on the temperature, the required pressure to maintain water in its condensed state is: for extraction at 300°C, a minimum pressure of 8.5 MPa is required, while a minimum pressure of 1.5 MPa is required for 200°C [118]. Of all the thermodynamical characteristics of water, the dielectric constant is one that changes significantly with increasing temperature. Dielectric constants are reached at 200°C that are similar to those of organic solvents such as methanol [119]. Hydroethanolic blends are the other fluid frequently utilized in PLE of bioactive components. The advantages of both can be used with solvent mixtures. For instance, one solvent, ET, can make the solute more soluble, and another, water, can help the solute desorb from the matrix [120]. The utilization of ET diminishes the boiling temperature and influences the solvent polarity. As a result, the amount of ET has a significant impact on the number of polyphenols that can be extracted [121]. The extraction yield is also influenced by temperature. Both the mass transfer and extraction rates can be increased by using a higher temperature. Monrad et al. [122], who found that a temperature of at least 80°C and a pressure of 6.8 MPa were necessary for an efficient procyanidin extraction from red grape pomace using PLE, validated the need for a high temperature. Due to the application of high temperatures (approximately 140°–150°C), certain compounds, such as Maillard reaction products and 5-(hydroxymethyl) furfural (HMF), can be generated de novo when using PLE [123, 124]. Additionally, sequential procedures can be utilized to increase extraction yields. For instance, SWE at 100°C, trailed by an extraction at 150°C was viewed as ideal to remove flavonols and GA [125]. Briefly, when extracting polyphenols from by-products, temperature, type of solute, and extraction medium were reported to be of major importance. Elmi Kashtiban and Esmaiili [58] discovered that SWE’s most effective variable for extracting the polyphenolic compounds from the grape skin was temperature. Additionally, they employed UAE as a pretreatment and discovered that the application of ultrasound as a pretreatment at 150°C, 40 bar, and 30 min yielded the highest levels of total phenolics, total flavonoids, antioxidant activity, and chroma.

Food products are subjected to pressures ranging from 100 MPa to 15,000 MPa with HHP technology. The mass transfer rate is increased and solvent penetration into cells through ruptured membranes is accelerated by the large differential pressure that develops between the interior and exterior of cell membranes under high pressure. Accordingly, the extraction yield will increase and more components will be released the higher the hydrostatic pressure [125]. The extraction efficiency can be improved by using more energy (higher pressure), but it can also cost more. Currently, industrial scale pressures up to 600 MPa are technically limited [126]. When extractions were aided by HHP, higher caffeine extraction yields from coffee and higher carotenoid content in tomato puree were demonstrated [127, 128]. Shouqin et al. [129] demonstrated that the use of HHP to extract flavanols from propolis is advantageous. The air gaps in fruit tissues are partially filled with liquid during HHP-assisted extraction. After that, the pressure is let go, and the air that was blocked in the pores escapes, causing damage to the plant cell membrane [130].

Corrales et al. [131] revealed that the highest antioxidant capacity was obtained at 70°C, 50% ET concentration, and 600 MPa high pressure, with anthocyanin recovery at 50°C being 23% higher than that of untreated treatments. Pomegranate juice’s anthocyanins produced a higher yield when they separated at 400 MPa and 25°C for 10 min as opposed to 500 MPa and 25°C for 5 min [132]. HHP was applied to the pulp of the raspberry puree in order to protect the anthocyanins and keep their color stable under a range of storage conditions. When HPP was applied to raspberry pulp at 200 MPa and 800 MPa, it preserved the pulp’s high color stability and anthocyanin concentration at 4°C as opposed to 30°C storage and ambient conditions [133]. Lonicera caerulea berry pulps had higher antioxidant capacities, phenol content, and anthocyanin content when low HHP was used for a longer period of time (400 MPa/20 min) as opposed to high HHP for a shorter period of time (600 MPa/10 min). At 200 MPa for 5 min and 10 min, the anthocyanin content increased by 6.84% and 14.35%, respectively. As a result, the extraction of anthocyanins could benefit from the improved long-term retention of bioactive compounds at low HHP [134]. Xi et al. [135] employed the HPP extraction method to extract polyphenols from green tea leaves. A variety of factors were assessed, such as the liquid/solid ratio [10:1 to 25:1 (mL:g)], pressure (100–600 MPa), holding time (1 min to 10 min), ET concentration (0% to 100%), and various solvents (acetone, methanol, ET, and water). The ideal extraction yield of polyphenols (13%) was obtained with 50% ET concentration, a liquid-to-material ratio of 20:1, and 500 MPa of HHP for 1 min. These conditions were similar to heat reflux extraction for 45 min, ultrasonic extraction for 90 min, and extraction at room temperature for 20 h, respectively. These data conveyed that the HHP extraction is more efficient contrary to the conventional extraction methods. In Table 1, the pros and cons of the different novel extraction methods are shown.

Lipid oxidative stability is one of the main parameters in food quality and sensory evaluation during shelf life. Lipid oxidation can occur in almost most food products specially based on the lipid and oil content amounts [174]. For instance, in meat products lipid oxidation is known as a quality control and spoilage factor because of the susceptibility of meat products to oxidative degeneration [175]. Lipid oxidative processes are influenced by (1) the presence of polyunsaturated fatty acids; (2) iron; (3) pro-oxidants; (4) endogenous antioxidants (endogenous antioxidants include enzymes (e.g., SOD, catalase, GSH-Px, glutathione reductase, coenzyme Q10) and non-enzyme components, such as nutrient-based antioxidants (e.g., tocopherols and tocotrienols, carotenoids, and lipoic acid) and metal-binding proteins (e.g., albumin, ferritin, ceruloplasmin, and lactoferrin) [176]; (5) the action of oxygen; (6) the addition of salt; (7) mechanical processes; (8) different animal species and their muscle structure. For instance, there is a series between different animal species based on stability: beef > pork > chicken > turkey > fish. Also, within a species of poultry, the dark (thigh) meat is more susceptible to oxidation than the white (breast) meat [175, 177]. Oxidation in meat products can occur before cooking (raw meat products) and also after cooking (cooked meat products) which in both systems needs to be controlled [175].

The mechanism of lipid oxidation starts as free radicals on cellular metabolism and lipid peroxidation reactions commensurate with the substantial damage to cells. The membranes of cells are composed of unsaturated (double bonds) fatty acids, which are very sensitive to peroxidation reactions. In fact, docosahexaenoic and arachidonic acids are among the major substrates of peroxidation in the membrane. Membrane properties like fluidity and permeability would depend on its structure and stability. Therefore, as a result of lipid peroxidation structure and functions can be destroyed. In biological cells, proteins and DNA are also sensitive targets for ROS [178]. Chelation of transition metals is an effective manner by which to inhibit lipid oxidation in food emulsions. Proteins like casein are known to have iron-binding ability, and many studies have reported the participation of phosphoryl groups in iron binding. Antioxidants also have been reported to have an ability to chelation of metals which causes and promotes oxidation and damage [179]. Other ways to escape oxidations are listed below:

(1)

Escaping from in photo-oxidation, wavelengths that are nearly ultraviolet A (UVA, 340–400 nm) and visible light (400–700 nm), along with an appropriated sensitizer such as chlorophyll and riboflavin, together with triplet oxygen (3O₂), lead to oxidative degradation of cholesterol through photodynamic reactions.

Foods of animal origin such as beef, poultry, fish, and dairy products are vulnerable to oxidation due to their high content of unsaturated compounds, e.g., fatty acids, cholesterol, etc. Further, the oxidation of cholesterol-containing foods appears non-enzymatically yet auto-oxidative through complex chain reactions based on the formation of free radicals. Additionally, critical factors in these auto-oxidation yet complex degradation processes include room temperature, light, and the presence of oxygen. Essential antioxidant enzymes naturally produced are known as the primary antioxidants, qualified by the donation of electrons or hydrogen to the free radicals formed within the initiation and propagation phases of lipid oxidation. The mechanism is based on the conversion of free radicals into either thermodynamically stable products and/or lipid-antioxidant complexes. The cholesterol in the food matrix is another molecule that may oxidize during the process when exposed to heat, free radicals, and oxygen. More so, the formation of cholesterol oxidation products (COPs) requires to be controlled and reduced [180]. Natural extracts (NEs) often contain high concentrations of phenolic compounds that have either strong H⁺ donating activity or high radical-absorbance capacity. Major phenolic constituents are acids (gallic, caffeic, and rosmarinic acids), diterpenes (carnosol and carnosic acid), flavonoids (quercetin, catechin, apigenin, kaempferol, naringenin, and hesperetin), and volatile oils (eugenol, carvacrol, thymol, and menthol). Phenolic acids inhibit the formation of free radicals and inactivate radical species. Besides acting as metal chelators, there are both initial and propagation stages of oxidative processes [167, 168, 171].

Polyphenols present in cocoa do inhibit oxidation effects, which could help prevent vascular ailments like arteriosclerosis, cardiovascular disease, and myocardial infarction. There was research on the antioxidant properties of cocoa. Polyphenols in cocoa could treat model rabbits with high cholesterol wherein low-density lipoprotein (LDL) contents in the blood decreased significantly. Also, polyphenols in cocoa could help reduce arteriosclerosis in mice. Furthermore, the cholesterol/lipid oxidation [detected by thiobarbituric acid reactive substances (TBARS)] contents reduced oxidative stress in tissues significantly [167, 181]. Moreover, natural antioxidants such as anthocyanins as intelligent packaging indicators could permit easier monitoring of packaged products during transportation/storage. To reiterate this, the design of the active packaging (AP) and intelligent system is shown in Figure 2, revealing the various components like wrap plastic low-density polyethylene (LDPE) film, intelligent packaging sensor, etc. [175]. Notably, conventional polymers (polyester, cellulose, polyethylene, etc.) applied to encapsulated antioxidant molecules would benefit agricultural/food packaging applications [173]. The functionality of natural antioxidants which are immobilized in a cover matrix is basically a color changer and indicators like anthocyanins from saffron petals in CTS nanofibers and methylcellulose matrix [175]. By extending indicator functionality, natural antioxidants can help prevent the oxidation process and same time, monitor inside intelligent packaging films.