Retention Of Antioxidant Activity Research Articles

Conformational and processing properties of a high-active ingredient involving soy protein isolates bound with anthocyanins and its application in cake baking

Soybean protein is of plant origin and is commonly appropriate for improving the processing characteristics of foods. This study aimed to explore a novel functional ingredient that contained soybean protein isolate (SPI) and blueberry anthocyanins (BANs). The spatial conformation and secondary structure of SPI-BANs complexes were analyzed using circular dichroism and fluorescence spectroscopy, the processing properties were investigated as well as the retention of antioxidant activity during thermal treatments. Results showed that the contents of free sulfhydryl and free amino groups in complexes increased to 3.50 and 1.19 folds than those of SPI, respectively, while the surface hydrophobicity decreased by 74.23%. Compared with SPI, the BANs-modified SPI had a smaller particle size of 29.12 nm and a lower zeta-potential of -8.73 mV and on the other hand, the complexes possessed higher solubility (83.08%) and foaming and emulsifying properties (115.08% and 54.03 m2/g). After fortification with SPI-BANs, the baking loss rate and adhesiveness of chiffon cake were reduced by 10.82% and improved to 0.24 N.mm, respectively. The high antioxidant activities of SPI-BANs under heat led to the cake’s bioactivities largely enhanced by 1.99 ~ 12.71 folds, being 345.19 µg Trolox/g for the DPPH radical scavenging activity. This study developed the functional food ingredients as antioxidants and a substitute for animal-based proteins in bakery products, which was safe and sustainable by using the dietary components from plant resources.Graphical

Ultrasonic Fabrication of Catechin Nanoemulsions from Green Tea with Enhanced Stability and Antioxidant Activity Optimized by Box-Behnken Design

Nanoemulsions are emulsions, either O/W (oil in water) or W/O (water in oil), with droplet diameters typically ranging from 50 to 1,000 nm. Research indicates that nanoemulsions are highly effective in enhancing the bioavailability, bioactivity, digestibility, stability, safety, quality and sensory attributes of food components. The study aimed to determine the optimum formulation and ultrasonic condition for fabricating catechin nanoemulsion (Ca-NE) from green tea with improved physical stability and antioxidant activity using response surface methodology. The effects of Medium Chain Triglyceride oil concentration (7.5 - 12.5 % w/w), Tween® 80 concentration (1 - 5 % w/w) and sonication time (5 - 15 min) on the droplet size, polydispersity index (PDI) and antioxidant activity presented by DPPH value of the Ca-NE were investigated using Box-Behnken design (BBD). The results found that droplet size and antioxidant activity of the Ca-NE were significantly (p < 0.05) affected by the proposed parameters, whereas the PDI value was slightly affected by those factors. The BBD results suggested that the Ca-NE fabrication condition was optimized with 7.5 % (w/w) oil concentration, 5 % (w/w) Tween® 80 concentration and a sonication time of 10.87 min. The optimum nanoemulsion showed good physical stability in terms of droplet size and PDI and had higher antioxidant activity than unencapsulated catechins when stored at 4 and 30 °C for 90 days. This study showed that catechin nanoemulsions fabricated by ultrasonication had good stability and antioxidant activity and, hence, had high potential for food and beverage applications in the food industry. HIGHLIGHTS The optimum nanoemulsion had good physical stability regarding droplet size and PDI when stored at 4 and 30 °C for 90 days. The ultrasonic fabrication of Ca-NE results in better retention of antioxidant activity than unencapsulated catechins. The ultrasonic fabrication provided the Ca-NE with good stability and high antioxidant activity. The results suggest that the obtained nanoemulsion of catechins has great potential in food or pharmaceutical applications. GRAPHICAL ABSTRACT

Effect of Different Drying Methods on Colour, Total Phenolic Content, Flavonoid Content, and Antioxidant Activity Retention of Strobilanthes crispus Leaves

Strobilanthes crispus, a medicinal herb, is recognised for its abundant phytochemicals, notably in its leaves, contributing to its high antioxidant activity. However, the crucial step of drying, aimed at extending shelf life, can impact the stability of these bioactive compounds. This study evaluates the impact of different drying methods, which include oven, microwave, freeze drying, and air drying, on the colour, phenolic and flavonoid content, and antioxidant activities of S. crispus leaves. The colour analysis of the fresh and dried leaves was assessed using the chromameter. Total phenolic content (TPC) and total flavonoid content (TFC) were determined using Folin-Ciocalteu’s and aluminium chloride colourimetric assays, respectively. Antioxidant capacities were analysed via ferric-reducing antioxidant power (FRAP) and a 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The results showed that microwave-dried S. crispus leaves exhibited minimal alterations in colour attributes L*, a*, and b*, closely resembling the fresh leaves (p > 0.05). Microwave drying significantly preserved TPC (145.42 ± 1.61 mg GAE/g), TFC (117.27 ± 5.10 mg QE/g), FRAP activity (258.92 ± 0.15 µg TE/g extract), and displayed the most potent DPPH scavenging half-maximal inhibitory concentration (7.58 ± 0.48 µg/ml) compared to other methods (p < 0.05). Notably, the DPPH scavenging potency surpassed that of the synthetic antioxidant butylated hydroxytoluene. In conclusion, microwave drying appeared to be an efficient method for preserving the colour and antioxidant properties of S. crispus leaves. It highlights its potential as a favourable drying technique for conserving bioactive compounds in medicinal plant materials, offering promising applications in the nutraceutical and pharmaceutical fields.

Enhancing encapsulation efficiency: Konjac glucomannan hydrolysate as a novel coating material for flavone derivatives in rice leaves extract

This study aimed to develop a novel coating material from Konjac Glucomannan Hydrolysate (KGMH) to flavone derivates from rice leaves extract (RLE). A suitable process for producing KGMH solution with different degrees of polymerization (DP) by enzymatic treatment was developed. Mannanase enzyme (250 and 150 units/g) were used in the hydrolysis process to obtain KGMH with lower (DP4 – 7) and higher DP (DP7 – 10), respectively. The solution was then used as a coating material in spray drying with an inlet air temperature of 190 °C, and the powder characteristics were assessed. The results showed that although the KGMH produced a lower production yield (64%–66%) compared to gum Arabic (72.45% ± 0.74%), KGMH was superior in terms of encapsulation efficiency of bioactive compounds (85%–95%) and antioxidant activity retention (90%–100%). FTIR spectra and X-ray diffraction confirmed the success of encapsulation by KGMH in the spray drying process. KGMH DP7-10 has successfully improved the bioaccessibility of Tricin O-glycoside after digestion. Furthermore, adding RLE encapsulated with KGMH enhanced and preserved tea products' bioactive compound content and antioxidant activity (3%–10% lower than after 24 days of storage).

Impact of spray drying operating conditions on yield, secondary metabolites, antioxidant potential and storage quality of grape (Vitis vinifera L.) pomace powder

In the present investigation, spray drying independent operating conditions such as the inlet air temperature (A-IAT 130, 150 and 170 °C), outlet air temperature (B-OAT 60, 70 and 80 °C), needle speed (C-NS 3S, 4S, 5S), maltodextrin concentration (D-MD 10, 15, 20 %), pump speed (E-PS 5, 10, 15 mL/min) and water/grape pomace ratio (F-W/GP ratio 10, 15, 20) were optimized to develop the spray-dried grape pomace powder (SDGPP) with maximum yield. The impact of these conditions on total phenolic contents (TPC), total flavonoid contents (TFC), and antioxidant activity (DPPH· values) of SDGPP samples were analyzed. The independent spray drying factors (IAT, OAT, NS, MD, PS, and W/GP ratio) impart a strong direct effect (p ≤ 0.05) on powder yield, TPC, TFC, and DPPH· values. The interaction effects (A × B, A × C, A × D, A × E, A × F, B × C, B × D, B × E, B × F, C × D, C × E, C × F, D × E, D × F, and E × F) of independent variables were noted non-significant (p ≥ 0.05) for response values. After validation of the model and verification of results, the independents' variables were found in the range of 170 °C (IAT), 80 °C (OAT), 4S (NS), 15 % (MD), 10 mL/min (PS) and 15 (W/GP ratio) for yield (64.7 ± 1.18 %), TPC (7.66 ± 0.53 mg GAE/g), TFC (3.19 ± 0.30 mg CE/g) and DPPH· 140.3 ± 1.59 (100 µL/mL), respectively. The decrease in TPC, TFC, and DPPH· values of SDGPP samples was noted during 60 days of storage at 25 ± 2 °C and 65 ± 5 % RH (p ≤ 0.05) but not greater than unprocessed samples. It could be concluded that the protection of phenolic contents and retention of antioxidant activity of dried powders can be achieved at optimized spray drying conditions for discerning food and byproduct processing industries.

Encapsulation of citrus polyphenols in multi-phase nano-emulsion: Preservative potential, bio-accessibility and cytotoxicity studies

Phenolic compounds in Citrus reticulata peels offer established nutraceutical benefits, contributing to improved health and well-being. However, their applications in the food industry are limited due to susceptibility to chemical degradation from oxygen, light, and heat. This study explores a novel approach to address this challenge by using ultrasonication to encapsulate these phenolic compounds in nano-emulsion. The developed nano-emulsions exhibited an average droplet size of 332 ± 14.67 nm, a polydispersity index of 0.29 ± 0.002, and a ζ-potential of -19 ± 1.82 mV. The major phenolic compounds observed in the nano-emulsion using HPLC included gallic acid (356.5 ± 1.41), p-coumaric acid (201.43 ± 0.81), chlorogenic acid (373.93 ± 4.38), ferulic acid (1278.8 ± 9.09), hesperidin (1192.56 ± 8.61), naringenin (570.63 ± 0.88), and quercetin (419.75 ± 4.47) μg/g. Encapsulated extract showed higher bio-accessibility compared to non-encapsulated extract. Specifically, the bio-accessibility index for total phenolic content was 42.80% and 73.89%, TFC was 44.75% and 75.70%, DPPH activity was 71.68% and 78.57%, and FRAP activity was 50.10% and 69.35% for phenolic extract and nano-emulsion, respectively. During 90 days of storage studies, maximum stability was observed for emulsions stored under refrigerated conditions, with 82.65% retention of phenolic compounds and 88.14% retention of antioxidant activity. Moreover, in addition to enhanced stability and bioavailability, the nano-emulsions demonstrated notable antimicrobial activity against both Gram-positive and Gram-negative bacteria, as well as pathogenic molds, showcasing promising preservative potential. Further, it was observed that the nano-emulsion exhibited no cytotoxic effects on Vero-cell lines (cell viability >85%). These findings suggested the potential application of these nano-emulsions in various facets of the food industry.

Biological stabilization of Arthrospira bioactive-peptides within biopolymers: Functional food formulation; bitterness-masking and nutritional aspects

Physicochemical/biological instability and bitterness are among the major challenges limiting the shelf life and direct use of bioactive-peptides in the production of functional foods. This study focused on the structural modification and improvement of biological, nutritional and techno-functional properties of blue-green algae protein by alcalase (30–180 min). Then, the optimal sample (H-120) was stabilized with maltodextrin (MD), gum-arabic (GA), WPC, alginate (A), and pectin (P) biopolymeric-carriers by the spray-drying process. The MD-WPC-encapsulated peptide presented the highest production yield (∼65%), retention of antioxidant activity, functional, flowability, and stability properties. Morphological (formation of wrinkled, irregular, and dented particles) and chemical (FTIR) evaluations respectively indicated the effect of feed composition on the structural properties and entrapment of peptides (through hydrogen bonds and hydrophobic reactions) in the polymer matrix. Finally, the optimal sample (SDP: MD-WPC) was used at different ratios (1, 2, and 4% w/w) for pan-bread fortification. The examination of physicochemical properties (moisture content, water activity, and specific volume), textural (porosity and compressive strength) indices, a color histogram (crust and crumb), antioxidant activity (DPPH• and ABTS• scavenging), and sensory analysis (color, texture, chewiness, taste, and overall acceptability) indicated biological stability, bitterness-masking, and the feasibility of functional bread production with 2%-SDP.

Effect of freezing, osmodehydro-freezing, freezedrying and osmodehydro-freezedrying on the physicochemical and nutritional properties of arazá (Eugenia stipitata McVaugh)

Arazá, a berry rich in heat-sensitive bioactives (phenolics/carotenoids/flavonoids/ascorbic acid), may be suitable for preparing functional foods, however, its high perishability hinders its industrial application. Although freezing (Fr) and freezedrying (LIO) are popular methods for preserving fruits, they may cause undesirable quality changes. Adding an osmo-dehydration pretreatment (OD) before freezing (osmodehydro-freezing/OD-Fr) or freezedrying (osmodehydro-freezedrying/OD-LIO) diminishes processing time which may improve the final product quality This study analyzed the effect of Fr/LIO/OD/OD-Fr/OD-LIO on color, antioxidant content/activity, polyphenol composition and bioaccessibility (BAC) of arazá.OD pretreatment increased freezing rate (58 %) and reduced osmodehydro-frozen arazá drip-loss (40%) Osmodehydrated samples presented the highest discoloration levels (15.7), freezing/freezedrying pretreated arazá improved them 16–48 %.Fr/LIO gave the best results regarding polyphenol content (99–48 %), and activity (97–88 %) retention; whereas OD/LIO produced the highest losses (59–84 %).Results showed that in comparison with untreated fruit, freezing arazá did not affect the bioaccessible antioxidants content/activity, conversely, freezedrying reduced antioxidant activity and total-flavonoids BAC levels (14–21 %) without modifying polyphenols/carotenoids bioaccessibilities.Although osmodehydro-freezing increased total-polyphenol bioaccessibility (22 %) without affecting that corresponding to total-flavonoids, it reduced antioxidant activity retention (16–42 %). Osmodehydro-freezdrying impact was negative on all properties (13–55 %) except Ferric-Reducing-Antioxidant-Power that increased (10 %).

Sonoprocessing enhances the stabilization of fisetin by encapsulation in Saccharomyces cerevisiae cells.

The objective of this study was to investigate for the first time the role of S. cerevisiae natural barriers and endogenous cytoplasmatic bodies on the stabilization of fisetin encapsulated via sonoprocessing coupled to freeze-drying (FD) or spray drying (SD). Both protocols of encapsulation improved the resistance of fisetin against thermal treatments (between 60 and 150 °C) and photochemical-induced deterioration (light exposition for 60 days) compared to non-encapsulated fisetin (antioxidant activity retention of approximately 55% and 90%, respectively). When stored under constant relative humidity (from 32.8 to 90%) for 60 days, yeast carriers improved the half-life time of fisetin by up to 4-fold. Spray dried particles were smaller (4.9 μm) and showed higher fisetin release after simulated gastrointestinal digestion (55.7%) when compared to FD. Freeze-dried particles, in turn, tended to agglomerate more than SD (zeta potential -19.7 mV), resulting in reduced loading features (6.3 mg/g) and less efficient protection of fisetin to heat, photo, and moisture-induced deterioration. Overall, spray-dried sonoprocessed fisetin capsules are an efficient way to preserve fisetin against harsh conditions. Altogether, this report shows that sonoprocessing coupled to drying is an efficient, creative, and straightforward route to protect and deliver lipophilic fisetin using yeast capsules for food applications.

Application of structurally modified WPC in combination with maltodextrin for microencapsulation of Roselle (Hibiscus sabdariffa) extract as a natural colorant source for gummy candy

The aim of this work was to improve the stability of Roselle extract (RE) by spray-drying using maltodextrin (MD) alone, and in combination with WPC in the forms of unmodified and modified (via ultrasonication, UWPC, or enzymatic hydrolysis, HWPC). Enzymatic hydrolysis by improving the surface activity of WPC increased spray-drying yield (75.1 %), and improved physical (flow) and functional (solubility, and emulsifying) properties of obtained microparticles. Degree of hydrolysis of the primary WPC (2.6 %) was increased to 6.1 % and 24.6 % after ultrasonication and hydrolysis, respectively. Both modifications caused a significant increase in the solubility of WPC, in a way that initial solubility (10.6 %, at pH = 5) was significantly increased to 25.5 % in UWPC, and to 87.3 % in HWPC (P < 0.05). Furthermore, emulsifying activity (20.6 m2/g) and emulsifying stability (17 %) indices of primary WPC (at pH = 5) were significantly increased to 32 m2/g and 30 % in UWPC, and to 92.4 m2/g and 69.0 % in HWPC, respectively (P < 0.05). FT-IR analysis indicated successful encapsulation of RE within carriers' matrix. According to FE-SEM study, the surface morphology of microparticles was improved when modified HWPC was used as a carrier. Microencapsulation of RE with HWPC showed the highest contents of total phenolic compounds (13.3 mg GAE/mL), total anthocyanins (9.1 mg C3G/L) as well as a higher retention of antioxidant activity according to ABTS+ (85.0 %) and DPPH (79.5 %) radicals scavenging assays. Considering all properties of microparticles obtained by HWPC next to their color attributes, it can be concluded that HWPC-RE powders could be used as natural colorant and antioxidant source for the fortification of gummy candy. Gummy candy obtained using 6 % concentration of the above powder gave the highest overall sensory scores.

Ultrasound-assisted encapsulation of curcumin and fisetin into Saccharomyces cerevisiae cells: a multistage batch process protocol

Some of the challenges of yeast encapsulation protocols are low phytochemical internalization rates and limited intracellular compartments of yeasts. This study uses an ultrasound-assisted batch encapsulation (UABE) protocol to optimize the encapsulation of curcumin and fisetin by recovering nonencapsulated biomaterial and further incorporating it into nonloaded yeasts in three encapsulation stages (1ES, 2ES and 3ES). The effect of selected acoustic energies (166·7 and 333·3 W l-1 ) on the encapsulation efficiency (EE), yield (EY) and antioxidant activity retention were evaluated, and then, compared with a control process (without ultrasound treatment). Compared to the control, enhanced EEs were achieved for both curcumin (10·9% control to 58·5% UABE) and fisetin (18·6% control to 76·6% UABE) after 3ES and the use of 333·3 W l-1 . Similarly, the yeast maximum loading capacity was improved from 6·6 to 13·4 mg g-1 for curcumin and from 11·1 to 26·4 mg g-1 for fisetin after UABE protocol. The antioxidant activity of produced biocapsules was positively correlated with the bioactive-loaded content of yeasts when ultrasound treatment was applied. Overall, results from this study provide valuable information regarding UABE processes, and moreover, bring new and creative perspectives for ultrasound technology in the food industry.

Polyphenol Encapsulates from the Waste Biomass of C. sinensis and Their Simulated Oral, Gastric, and Intestinal Stability Studies: Nutraceutical Application

Extraction of bioactive metabolites from waste biomass is a recent area of research; hence purification and HPLC-DAD-based quantification of polyphenols from neglected parts (fruit, flower, and coarse leaves) of Camellia sinensis were carried out. Purification of polyphenols was performed via fractionation process, and purity was attained up to 77%, while the quantified content of catechins attained up to 63.3% with excellent free radical inhibition (78.89–97.20%). Aiming the controlled release of polyphenols with improved shelf life, microencapsulates were prepared by spray-drying and freeze-drying processes. Maltodextrin and soy lecithin were used as two different wall materials, and maximum encapsulation efficiency was attained up to 69.05%. Furthermore, in vitro simulated studies presented maximum release (>50%) of catechins in the gastric phase followed by intestine and oral phases. Stability studies of free and microencapsulated polyphenols were performed with respect to quantified content of catechins and free radical scavenging activity. The findings resulted in a significant effect of microencapsulation on the release profile and stability of catechins as well as retention of antioxidant activity. Hence, this study suggests a new perspective for the utilization of bioactive microencapsulates from waste tea plant biomass to develop value-added products.

Influence of blanching and guar gum pretreatments on total phenolic content and antioxidant activity of cabinet-dried white bitter gourd Momordica charantia L.

Currently, the global food industry is experiencing a shift in consumer preference towards natural sources of antioxidants derived from edible fruits and vegetables. In view of this, white skinned bitter gourd with bioactive properties has great potential. Additionally, guar gum has the characteristic ability to form strong hydrogen bonds with water molecules, thereby reducing shrinkage during dehydration. Thus, the present investigation was carried out to study the influence of blanching and guar gum pretreatment on the retention of the total phenolic content (TPC) stability and antioxidant activity (AA) of white Momordica charantia L. when cabinet dried at 60±5 °C. The results are indicative of a significant (P values of &lt; 0.05) impact of using guar gum along with blanching before dehydration of white Momordica charantia. The findings obtained clearly show the positive impact of guar gum on the stability and retention of TPC (Folin Ciocalteau) and AA (percentage of 2,2-diphenyl-1-picrylhydrazyl DPPH scavenging activity) in the dried product in comparison to the untreated control. Water Blanching + 1% Guar gum (T5) and 2%Salt Blanching + 0.2% Potassium meta bisulphite + 1%Sodium carbonate + 1% Guar gum (T16) showed higher AA [20.29% (T5) and 40.13% (T16)] and TPC [30.8 (T5) and 39.5 (T16) GAE per 100 g of dried weight (DW)]. Therefore, the application of guar gum as a pretreatment with blanching turns out to be beneficial for higher retention of TPC and AA, thereby maintaining product quality as a whole.

Techno-functional, biological and structural properties of Spirulina platensis peptides from different proteases

This study focused on the effects of different proteases (alcalase, trypsin, pancreatin, and pepsin) on amino acid composition (AAC) and nutritional, techno-functional, antioxidant, structural, and antibacterial properties of Spirulina (SP) protein and its hydrolysates (SPHs). Evaluation of AAC, including essential (30 %), hydrophobic (44 %), and antioxidant (17 %) types, as well as protein efficiency ratio (PER 2.45) indicated the potential of SP and SPHS as the sources of antioxidants with good nutritional and digestibility properties. Enzymatic hydrolysis improved the techno-functional properties (solubility, emulsion, foaming, and water/oil holding capacities). The highest antioxidant activity of SP and SPHs, including Trolox equivalent antioxidative capacity (1.47–2.56 mM), DPPH (24.8–68.6 %), hydroxyl (36.5–76.2 %), nitric oxide (9.1–28.5 %), reducing power (0.73–1.16), total antioxidants (0.87–1.85), and chelation of iron (42.7–73.5 %) and copper (18.5–49.5 %) transition metals were affected by the type of enzymes and the concentration of peptides. Thermal and acidic conditions led to extensive changes in secondary structures (amide A and amides I, II, and III regions), unfolding, and acceleration of protein aggregation. Enzymatic hydrolysis improved the retention of antioxidant activity at different temperatures and acidic conditions. The results of antibacterial tests revealed good activity of alcalase-hydrolyzed protein in growth inhibition of Escherichia coli (14.7 mm) and Bacillus cereus (11.6 mm). Finally, the results of this study demonstrate the usability of SPH in various functional food formulations (acidic and alkaline) as well as in processed and cooked foods.

Fenugreek seed (Trigonella foenum graecum) protein hydrolysate loaded in nanosized liposomes: Characteristic, storage stability, controlled release and retention of antioxidant activity

This study aimed to produce fenugreek protein hydrolysates by alcalase, pancreatin, pepsin and trypsin at hydrolysis time of 30–180 min and loading the hydrolysates in nanoliposomes to improve the bioavailability. Instability and untargeted delivery of fenugreek protein hydrolysates limit the use of their health beneficial properties. Loading protein hydrolysates in nanoliposomes can reduce these limitations and the addition of cholesterol to liposome formulation, in some cases, can help the vesicle assembling. Fenugreek protein hydrolysates produced by alcalase and pancreatin showed the highest antioxidant potential, so they have been and loaded into nanoliposomes containing 0.01–0.03% cholesterol. The physicochemical properties, antioxidant activity, stability, release rate, encapsulation efficiency and morphology of nanoliposomes were evaluated. Nanoliposomes were spherical particles with smooth surfaces and the average size of 16.53–25.75 (nm). The addition of cholesterol to liposomes address an increase of encapsulation efficiency of protein hydrolysates and stability of vesicles. When 0.03% of cholesterol was used the best features were obtained. FTIR spectroscopy indicated that fenugreek protein hydrolysates located inside the polar parts of vesicles and formed hydrogen bonds with phosphatidylcholine. In conclusion, nanoliposomes containing 0.03% cholesterol are efficient for protecting the bioactivity of fenugreek protein hydrolysates and their control release.

Amla essential oil‐based nano‐coatings of Amla fruit: Analysis of morphological, physiochemical, enzymatic parameters, and shelf‐life extension

This study aimed to develop and examine the potential effect of Amla essential oil-based nano-coatings at different concentrations 0.0, 2.5, 5.0, 7.5, and 10.0% (v/v) on Amla fruits stored in the room conditions (29 ± 2°C and 45%RH) for 15 days. Nanoemulsions were formulated by ultrasonication with Amla essential oil along with modified corn starch (2% w/v) and Tween 80 (5% v/v). All the shelf-life parameters were analyzed at an interval of 3 days. Results have shown that nano-coatings have a positive and significant effect on delaying browning and total yeast and mold count. Fruits having nano-coatings effectively retained their antioxidant activity along with bioactive components in comparison with the uncoated fruits. Particle size, Zeta potential, and polydispersity index of the best-performed nano-coating having 10% (v/v) of Amla essential oil were also evaluated. Thus, our findings suggest that Amla essential oil-based nano-coatings had a promising effect on enhancing the shelf life of Amla fruits. Novelty impact statement The fruits coated with nanoemulsions maintained good fruit quality with a lower decay percentage, the least degradation of ascorbic acid and chlorophyll, and high retention of antioxidant activity and bioactive compounds. The application of Amla essential oil-based nano-coatings had a promising effect on fungal decay, weight loss, firmness, browning index, and other color attributes of fruits. Amla essential oil-based nano-coatings had a promising effect on enhancing the shelf life of Amla fruits.

Effect of chitosan coating on the properties of nanoliposomes loaded with oyster protein hydrolysates: Stability during spray-drying and freeze-drying

Oyster protein hydrolysate (OPH) has high bioactivity and excellent performance, but its application in food formulation is still limited due to poor flavor and instability. In the present study, OPH was prepared by enzymatic hydrolysis and loaded into nanoliposomes. Then, the effects of chitosan coating (0, 0.25, 0.5, and 1.0%) on the physical properties, stability, and antioxidant activity were evaluated. The results showed that 1% chitosan-coated nanoliposomes had high encapsulation efficiency (EE) and physical stability. Additionally, chitosan coating slowed the release rate of nanoliposomes and increased the retention rate of antioxidant activity of OPH. The stability of the uncoated/coated nanoliposomes in a maltodextrin matrix by spray/freeze drying was evaluated. FTIR spectrum showed that hydrogen bonds, hydrophobic, and electrostatic interactions had been formed between chitosan-coated nanoliposomes and maltodextrin. Chitosan coating significantly improved the physical stability and antioxidant activity retention of nanoliposomes during powder reconstitution.

Preparation of Water-in-Oil Nanoemulsions Loaded with Phenolic-Rich Olive Cake Extract Using Response Surface Methodology Approach.

In this study, we aimed to prepare stable water-in-oil (W/O) nanoemulsions loaded with a phenolic-rich aqueous phase from olive cake extract by applying the response surface methodology and using two methods: rotor-stator mixing and ultrasonic homogenization. The optimal nanoemulsion formulation was 7.4% (w/w) of olive cake extract as the dispersed phase, and 11.2% (w/w) of a surfactant mixture of polyglycerol polyricinoleate (97%) and Tween 80 (3%) in Miglyol oil as the continuous phase. Optimum results were obtained by ultrasonication for 15 min at 20% amplitude, yielding W/O nanoemulsion droplets of 104.9 ± 6.7 nm in diameter and with a polydispersity index (PDI) of 0.156 ± 0.085. Furthermore, an optimal nanoemulsion with a droplet size of 105.8 ± 10.3 nm and a PDI of 0.255 ± 0.045 was prepared using a rotor-stator mixer for 10.1 min at 20,000 rpm. High levels of retention of antioxidant activity (90.2%) and phenolics (83.1–87.2%) were reached after 30 days of storage at room temperature. Both W/O nanoemulsions showed good physical stability during this storage period.

Valorization of Peel-Based Agro-Waste Flour for Food Products: A Systematic Review on Proximate Composition and Functional Properties

With the steadily growing world population, effective methods are needed to alleviate food shortages. One possible strategy could be to utilize agro-waste materials that accumulate in large quantities at every stage of the economic chain during harvesting, food production, and consumption. Peel-based agro-waste consists of promising materials that can be utilized to potentially substitute commonly used raw materials in products traditionally made from wheat, tapioca, and rice flours. In this systematic review, we aim at establishing prospective proximate components as basic nutrients and their valorization potential as substitutes in traditional flour products (bread, biscuits, etc.). Generally, the peel contains high levels of fiber and relatively low digestible carbohydrates, providing a healthier food ingredient. In terms of protein, it should be pointed out that seeds such as wheat utilize insoluble gluten as their major storage protein, while proteins in peel were found in quite high percentage although they were not yet well characterized. However, the general effect of using peel to substitute wheat in food products are the reduction of dough elasticity, increased hardness of the end-products, faster water absorption rate of the products, and in some cases, bitter taste and darker colors. The latter two could have been contributed by the secondary metabolites such as phenolic compounds. On the other hand, substitution of peel into food products can have valuable health benefits, e.g., retention of antioxidant activity due to the phenolic compounds or simply adding fiber. In this review, literature on the composition of promising agro-waste raw materials is being discussed in the relationship with physical properties and appearance of potential end-products. Antinutritional compounds and pretreatment processes are also being considered. It is hoped that a critical discussion will lead to a better understanding and higher acceptance of the incorporation of peel into food products.

Effect of High Hydrostatic Pressure Processing on the Anthocyanins Content, Antioxidant Activity, Sensorial Acceptance and Stability of Jussara (Euterpe edulis) Juice.

Jussara (Euterpe edulis) fruit is a strong candidate for exportation due to its high content of anthocyanins. However, its rapid perishability impairs its potential for further economic exploration, highlighting the relevance of producing ready-to-drink juices by applying innovative processing, such as high hydrostatic pressure (HHP). The effect of HHP (200, 350, and 500 MPa for 5, 7.5, and 10 min) on anthocyanins content and antioxidant activity (AA) by FRAP and TEAC assays, and the most effective HHP condition on overall sensory acceptance and stability of jussara juice, were investigated. While mild pressurization (200 MPa for 5 min) retained anthocyanins and AA, 82% of anthocyanins content and 46% of TEAC values were lost at the most extreme pressurization condition (500 MPa for 10 min). The addition of 12.5% sucrose was the ideal for jussara juice consumer acceptance. No significant difference was observed for overall sensory acceptance scores of unprocessed (6.7) and HHP-processed juices (6.8), both juices being well-accepted. However, pressurization was ineffective in promoting the retention of anthocyanins and AA in jussara juice stored at refrigeration temperature for 60 days, probably due to enzymatic browning.