Increase In Peroxide Value Research Articles

Establishing a biodegradable film with gluten and tea polyphenols: Structure, properties, and function

Film packaging is a common method to extend the shelf life of food during storage. But the non degradability and potential toxicity of some synthetic films are gradually limiting their usage in food packaging. In present study, gluten and tea polyphenols were utilized to prepare a packaging film, and the properties of this film were determined. With addition of tea polyphenols, thickness and tensile properties of film were improved. By using scanning electron microscope, fourier transform infrared spectra and molecular docking, this film showed a dense network structure, which was due to the strong interactions between tea polyphenols and gluten. Hydrogen bonds and hydrophobic interactions were the main molecular forces during the interactions. Meanwhile, the film showed the good thermal stability and barrier properties. In addition, this film exhibited the remarkable capability to scavenge free radicals and inhibited the increase of peroxide value of oil during storage. Moreover, this film had the slow-release properties of tea polyphenols, and could be biodegradable in nature. All present results suggested that tea polyphenols improved the properties and functions of gluten film effectively, and this complex film showed the potential for food preservation in food industry.

Assessment of Multifunctional Activity of a Postbiotic Preparation Derived from Lacticaseibacillus paracasei Postbiotic-P6.

Postbiotics possess various functional activities, closely linked to their source bacterial strains and preparation methods. Therefore, the functional activities of postbiotics need to be evaluated through in vitro and in vivo methods. This study aims to prepare a postbiotic and explore its antihemolytic, anti-inflammatory, antioxidant, and antibacterial activities. Specifically, a postbiotic preparation named PostbioP-6 was prepared by intercepting 1-5 kDa of Lacticaseibacillus paracasei Postbiotic-P6 fermentation broth. The results demonstrate that PostbioP-6 exhibited notable biological activities across multiple assays. It showed significant antihemolytic activity, with a 4.9-48.1% inhibition rate at 10-50% concentrations. Anti-inflammatory effects were observed both in vitro, where 8-40% PostbioP-6 was comparable to 259.1-645.4 μg/mL diclofenac sodium, and in vivo, where 3.5 and 4.0 μL/mL PostbioP-6 significantly reduced neutrophil counts in inflamed zebrafish (p < 0.05). Antioxidant properties were evident through increased reducing power (OD700 increased from 0.279 to 2.322 at 1.25-12.5% concentrations), DPPH radical scavenging activity (38.9-92.4% scavenging rate at 2.5-50% concentrations), and hydroxyl radical scavenging activity (4.66-10.38% scavenging rate at 0.5-4% concentrations). Additionally, PostbioP-6 demonstrated antimicrobial activity against two Gram-positive bacteria, eight Gram-negative bacteria, and one fungus. Furthermore, PostbioP-6 significantly inhibited the increase in peroxide value and malondialdehyde content in cookies, highlighting its potential application in food preservation. In conclusion, we prepared a novel postbiotic, termed PostbioP-6, which proved to have prominent anti-hemolytic, anti-inflammatory, antioxidant, and broad-spectrum antimicrobial activities. The multifunctional properties of PostbioP-6 position it as a potentially effective functional food supplement or preservative. In the future, further research is necessary to elucidate the precise mechanisms of action, identify the active components, and validate its biological activities in animal models or clinical trials.

Lipidomics reveals the effect of hot-air drying on the quality characteristics and lipid oxidation of Tai Lake whitebait (Neosalanx taihuensis Chen)

The present study aimed to investigate the impact of temperature on the quality attributes, particularly lipid oxidation and phospholipid molecular species, of Tai Lake whitebait during hot-air drying. Fresh samples of Tai Lake whitebait were subjected to heat treatment and were dried at temperatures of 40, 50, 60, and 70 °C for 12 h. The results indicated significant and continuous increases in peroxide values (POV), thiobarbituric acid reactive substances (TBARS), and saturated fatty acids (SFA) contents during hot-air drying, but reductions in monounsaturated fatty acids (MUFA). During the hot-air drying process, the mass fraction of triacylglycerol (TAG) and phospholipid (PoL) decreased, while the fractions of diacylglycerol (DAG), monoacylglycerol (MAG) and free fatty acid (FFA) increased. Furthermore, the drying treatment led to a more pronounced reduction in Phosphocholine (PC) content compared to phoethanolamine (PE). A total of 17 phosphatidylcholines (PC), 18 phosphatidylethanolamine (PE), 7 phosphatidylinositol (PI), and 9 phosphatidylserine (PS) molecular species were identified. By comprehensively considering the drying time and quality attributes, 50 °C was selected the ideal temperature for drying. The findings of the investigation revealed that thermal drying significantly influenced the quality attributes and lipid oxidation of Tai Lake whitebait. The insights gained from this study are valuable for improving the drying process for Tai Lake whitebait and enhancing its overall quality.

Development of non‐dairy creamer with modified fatty acid profile and high Omega‐3 and 6 at a non‐dairy creamer plant

SummaryA study was conducted to develop non‐dairy creamer production with a modified fatty acid profile having high levels of omega‐3 and 6, by using raw materials collected from the Republic Foods industrial non‐dairy creamer plant. The non‐dairy creamer formulation aimed to maintain a balanced 1:1:1 ratio of polyunsaturated, monounsaturated and saturated fatty acids. The ingredients used included palm olein, stearin, RBD palm oil, rice bran oil, soybean oil, coconut oil and palm kernel oil. The mixture proportions tested were determined using Design Expert software, for in total 20 different formulations. From these, six formulations were selected based on their fatty acid profiles, which closely approximated the desired 1:1:1 ratio of polyunsaturated, monounsaturated and saturated fatty acids. To complement the physicochemical results, a quality control and research officer from Republic Foods industrial conducted a comprehensive evaluation of various properties of the non‐dairy cream samples intended for use in coffee. It is noteworthy that formulation number 20 received the highest scores across all tested properties. This formulation had 50.53% palm olein, 1.00% stearin, 1.00% RBD palm oil, 1.00% rice bran oil, 44.47% soybean oil, 1.00% coconut oil and 1.00% palm kernel oil. This combination results in a fatty acid ratio of 1:1:0.8 (PUFA:MUFA:SFA) at the least production cost. The developed non‐dairy creamer exhibited the highest total energy content, namely 519 kilocalories/100 g, when compared with commercial brands. However, after a storage period of 90 days, the peroxide value reached 6.18 ± 0.22 mEq kg−1 of fat, which is below the FDA standard limit of 10.0 mEq kg−1 fat. This trend in peroxide value increase over the 90‐day storage period aligns with the behaviour of TBA, which also showed an upward trend during storage.

Quality Evaluation of Refrigerated Salted Butter Made with Goat and Cow Milk

Butter is a dairy product that is susceptible to oxidation, which causes a rancid taste and a short shelf life. The quality of the butter depends on the quality of milk. The aim of the study is to determine the quality of butter made from goat and cow reared by small-scale farmers in Yogyakarta with the traditional manufacturing process. The milk of Saanen-Peranakan Ettawa (Sapera) goats and Fresian Holstein were taken from farmers in Sleman district, Yogyakarta, Indonesia. Butters were sampled after 0, 15, 30 days storage. This study used the Nested Design method , namely the nested quality of butter in the type of milk. The result showed that butter made from cow milk produced a higher fat content compared to goat milk butter (P&lt;0.05), namely 85.29 ± 0.04% and 80.10 ± 0.27%. The acid value increased while pH value was decreased during storage (P&lt;0.05). There was no increase in peroxide value in cow butter but there was an increase in goat butter on day 0 to day 15 (P&lt;0.05). It can be concluded that the goat and cow milk reared by small-scale farmers in Yogyakarta have good quality so it produced good quality butter which is still good for consumption until 30 days of storage in the refrigerator.

Refining quinoa storage stability through microwave-induced structural alterations and activity suppression of key enzymes

This study investigated the effects of microwave on preserving the quality of quinoa during storage. Quinoa treated with 9W/60s exhibited a significant decrease in fatty acid values compared to hot air treatment. Microwave effectively delayed lipid oxidation during quinoa storage by suppressing the increase in peroxide values. MDA gradually accumulated from peroxides during storage, reaching its peak at 0.423 μmol/L in the second week. Microwave disrupted the original hydrogen bonds in lipase, causing the unwinding of the α-helix and resulting in the loss of its regular structure. Microwave reduced the stability of the β-sheet structure in lipoxygenase, breaking the natural secondary structure composition. The observed fluorescence and UV spectra features were similar, indicating that microwave alter the peptide chain of the enzyme's skeletal structure, increasing the exposure of hydrophobic chromophores. These results indicated the potential of microwave to enhance the stability of quinoa during storage.

The bioprotective role of irradiated hibiscus against harmful effects of using repeatedly frying edible oil.

Repeatedly frying process of dietary edible oil has a potential role in the generation of free radicals. Therefore, questions have always been raised as to whether, there is an efficient and economical method to reduce the harmful effects of repeated use of frying edible oil. Since hibiscus has been stated to have a wide variety of therapeutic effects, it was important to investigate its properties against harmful effects of free radicals. The current study aspires to find out whether irradiated powder of hibiscus has a protective role against adverse effects of repeated use of frying edible oil. Thirty-five adult male albino rats were equally assigned into five groups. First group"G1" was fed with normal diet as control group, meanwhile, group"G2" the diet mixed with fresh oil, "G3" diet mixed with repeatedly frying oil only, "G4" diet mixed with frying oil treated with hibiscus and "G5" diet mixed with frying oil treated with irradiated hibiscus. Feeding duration was six weeks. Fatty acid analyses of oil as well as peroxide values were determined. Blood and liver samples were collected for biochemical analyses as well as histological study. Repeatedly heated cooked oil has significant increases in peroxide value, acid value, free fatty acid and both conjugated diene and triene compared with repeatedly frying oil treated with hibiscus. Also there are significant increases in cholesterol and triglyceride and impaired in liver functions in "G3"compared with others. In addition, relative to the hibiscus groups, there is a substantial reduction in oxygen consumption in "G3". Both hibiscus as well as irradiated hibiscus attract attention in order to play a vital and economical role against harmful effects of frequent use of frying edible oil on some biological functions but, irradiated hibiscus was more effective.

The effect of sesamol on endogenous substances and oxidative stability of walnut oil.

This study explored the effect of sesamol on the stability of walnut oil based on the changes of endogenous characteristics in the oxidation process, which provided a theoretical reference for the application of natural antioxidants in walnut oil. A total of 300 mg/kg sesamol (SP), compound antioxidant AC (sesamol 353.62 mg/kg, citric acid 149.60 mg/kg, and BHA 76.33 mg/kg) and 35% sesame oil (35%-SO) were added to walnut oil respectively; in addition, 200 mg/kg t-butylhydroquinone (TBHQ), butylated hydroxyanisole (BHA), and citric acid were used as controls and blank walnut oil to study their effects on peroxide value, acid value, carbonyl compounds, conjugated olefins, phenols, flavonoids, sterols, vitamin E, β-carotene, and 51 fatty acids of walnut oil and their correlation between endogenous antioxidant components. The results showed that the addition of SP, 35%-SO, and AC could inhibit the increase of peroxide value, acid value, and carbonyl compounds in walnut oil, and could inhibit the decrease of β-carotene, total phenols, total sterols, and vitamin E. SP and 35%-SO could inhibit the decrease of total flavonoids, and several antioxidants could inhibit the decrease of endogenous antioxidant components in walnut oil. At the same time, it can better inhibit the change of unsaturated fatty acids in walnut oil. By the end of oxidation, the unsaturated fatty acids of blank walnut oil decreased by 10.31%, but AC, SP, and 35%-SO treatment groups increased by 10.90, 5.09 and 4.13%, respectively. Indicating that it had a certain protective effect on unsaturated fatty acids in walnut oil. There was a certain correlation between the endogenous substances of walnut oil. so the addition of several antioxidants can enhance the endogenous antioxidants of walnut oil, inhibit the oxidation of unsaturated fatty acids, and inhibit the increase of carbonyl compounds, codienes, acid value, and peroxide value. SP and AC have better antioxidant effects on walnut oil and improve the stability of walnut oil.

A comparative study between the performance of thymol-nanoemulsion and thymol-loaded nanostructured lipid carriers on the textural, microbial, and sensory characteristics of sausage

The objective of this research was to compare the function of thymol-loaded nanostructured lipid carriers (NLC) and a thymol-nanoemulsion (NE) with nitrite (120 mg/kg) on quality parameters of sausage. The droplet size of the NLC and NE was 140 and 86.39 nm with encapsulation efficiency of 97 and 94%, respectively. The results on sausage showed that all samples containing NLC and NE exhibited the lowest increase in peroxide value, total volatile base-nitrogen, and TBA with the highest inhibitory effect on the growth of E. coli, C. perfringens, lactic acid bacteria, psychrophilic bacteria, mold and yeast, and total viable counts as well as good texture and sensory attributes with the best results in the NLC + nitrite and NE + nitrite samples. The L* and a* values were relatively higher in the samples treated with nitrite, NLC + nitrite, and NE + nitrite after 4-week storage. This increase in redness was associated with the maintenance of oxymyoglobin levels and a decrease in metmyoglobin production. The results of this study indicated that the combined use of NLC/NE (particularly NE) with 60 mg/kg nitrite significantly improved the oxidative and color stability, and delayed the spoilage and off-flavor in sausage.

THE IMPACT OF TEMPERATURE AND ANTIOXIDANTS ON OXIDATION AND THE FORMATION OF TRANS FATTY ACIDS IN SEVERAL PALM OIL DERIVATIVES

The quality of palm oil is strongly influenced by temperature. The oxidation of palm oil can be caused by high temperatures. The higher the storage temperature, the faster oxidation occurs. In this research, the temperature significantly affects the quality of several palm oil derivative products such as Palm Olein, Palm Stearin, Palm Kernel Oil, and Palm Kernel Stearin. Antioxidants are very effective in resisting the increase in the oxidation reaction of some palm oil commodities. With the addition of tertiary butylhydroquinone (TBHQ) or butylated hydroxytoluene (BHT), the increase in peroxide value, p-anisidine values, free fatty acid, color tends to be slower than without the addition of antioxidants. For PV, BHT was the most effective antioxidant for RPKOL at a 29.75% increase, RBDOL at 9.91%, and RBDST at 5.26% but for RPKS TBHQ was the most effective increase at 19.83%. For anisidine value, TBHQ+BHT was most effective for RPKOL with a 61.62% increase, TBHQ for RPKS with 76.76%, BHT for RBDOL and RBDST with 15.37% and 14.46%. In the FFA test, BHT was effective for RPKOL and RPKS with a percentage increase of 6.48% and 6.67%, but TBHQ was effective for RBDOL and RBDST to controlled FFA with an increase of 8.41% and 3.38%. In color testing, TBHQ proved to be the effective antioxidant for RPKOL and RBDOL, resulting in percentage increases of 8.71% and 2.13%, respectively. For RPKS, the combination of TBHQ and BHT was employed, resulting in no percentage increase (0%). Additionally, BHT at 3.85% was used for RBDST. At a temperature of 130°C, an oxidation process was observed, indicating the formation of an aldehyde compound. This was evidenced by the FT-IR spectrum, showing peaks at wave numbers 1760 cm⁻¹ (C=O of aldehyde) and 2900 cm⁻¹ (CH on aldehyde). In this research, we can also see the formation of trans fatty acids C18:1n9t in GC-FID's peak area

Optimization of Skipjack Tuna (Katsuwonus Pelamis) Quality Factors in Chilled Box Storage Using Taguchi Method

Skipjack tuna (Katsuwonus pelamis) is one of tuna fish species in Indonesia,which is perishable and must be kept its freshness by chilling. Aim of this research were to optimize influenced quality factors and to find the best method for reduce deterioration process. The research was conducted by using Taguchi Method, which was used quality robustness concept and multi-performance characteristics to achieve optimal combination of factors. Controlled factors during chilled storage were; weight ratio of ice and fish (A), box size (B), time replacing ice (C), ice form (D), concentration of added salt (E), fish form (F) and number of fishes per kg (G). Quality responses for assessing the freshness were; peroxide value (POV), water content (WC), pH value, texture and Total Plate Count (TPC). The result showed, increase of peroxide value was affected by A of 26.52% and C of 26.52%. Increase of water content was influenced by F of 37.25%. Fluctuation of pH was affected by G of 59.58%. Decrease of texture was influenced by A of 40.47%. Increase of TPC was influenced by A of 31.20%. Priority Scale of factors during storage were A, E, D, G, F, B, and C. Result of analysis muli-performance characteristics gave a conclusion that factors A1, B1, C1, D2, E2, F2 and G2 are the best chilling storage methods.

Characteristics of virgin coconut oil (VCO) microencapsulation using O/W emulsification and complex coacervation methods

Virgin coconut oil (VCO) is produced by processing the flesh of coconut (Cocos nucifera L.). It has beneficial health effects due to the medium-chain fatty acids (MCFA), vitamins, and antioxidant contents. Since liquid VCO is not widely accepted by consumers for direct consumption, further processing into powder VCO can be achieved using microencapsulation methods, such as single-layer emulsification (SL), layer-by-layer emulsification (LBL), and complex coacervation (CC). Therefore, the present work aimed to determine the characteristics of microencapsulation of VCO powder by emulsification and coacervation complex methods over 30 days of storage period. Results showed that SL VCO emulsion remained stable for three days of storage, while LBL VCO emulsion experienced syneresis. The particle size of the reconstituted VCO powder was also larger than the fresh emulsion. LBL microcapsule had the highest yield at 74.17%, and there was an increase in moisture content (MC) during 30 days of storage in CC microcapsule. Meanwhile, MC of SL microcapsule was constant, and the equilibrium MC of LBL was retained during 15 days of storage. A microencapsulation efficiency of up to 78.65% was obtained for CC, and the value decreased for all microcapsules during the 30 days of storage. Different oxidative characteristics were also reported, resulting in increased peroxide value of VCO powder. Furthermore, all microcapsules had amorphous and glassy surface morphology, as well as different characteristics and stability during storage.

Influence of Multiple Deep-Frying Cycles on the Characteristics of Corn Oil and Acrylamide Content in French Fries

Reusing oil in deep-frying is a common practice in homes and restaurants, with little knowledge of its negative effects. The present study investigated the physicochemical properties of corn oil (CO) and acrylamide content (AA) in French fries during four deep-frying cycles. Results revealed that the lowest level of AA contamination was 24.65 ppm during the first frying cycle, while the highest level was 55.91 ppm after four frying cycles, indicating increased acrylamide formation. Repeated frying led to detrimental changes in CO, including significant increased peroxide value, acid value, free fatty acids, viscosity, and density, decreased smoking point, and iodine number, signifying reduced thermal stability and unsaturation level. DPPH assay showed antioxidant activity decreased from 41.51 to 23.41, while TFC decreased from 20.29 to 15.02 and TPC decreased from 14.85 to 3.97 after four frying cycles, indicating the declining quality of CO after reusing it in the deep-frying method.

Walnut green husk extract enhances the effect of chlorine dioxide on kernel quality and antioxidant properties of fresh-eating walnuts during their shelf life.

Fresh-eating walnuts are perishable and become mildewed during shelf life, limiting their sales span. The effects of chlorine dioxide (ClO2) alone and its combination with walnut green husk extract (WGHE) on shelf stored fresh walnuts were investigated to develop a pollution-free preservative for the produce. The initial development of mildew incidence was delayed by both treatments under 25°C, whereas, WGHE+ClO2 acted more effectively than ClO2 under 5°C. The WGHE+ClO2 treatment presented superior effects on improving moisture, soluble sugar and total phenol content, alleviating loss of oil and unsaturated fatty acid and delaying peroxide value increase of walnut kernels at both temperatures. Both treatments inhibited the activities of three lipolytic enzymes and two oxidases at 25°C and 5°C, WGHE+ClO2 acted more effectively at 5°C. The results guide the combined application of WGHE with ClO2 on shelf preservation of fresh walnut.

Characterization and stability evaluation of Egyptian propolis extract nano-capsules and their application

The increasing demand for natural products and biotechnological activities from bees facilitate their widespread use in food preservation and beneficial effects on humans. This study aimed to prepare and characterize the nano-capsules of Qaluiobia (PQG) governorates propolis extracted with water, ethanol and supercritical fluid-carbon dioxide at 50 °C with co-solvent. Propolis bioavailability was analyzed and introduced to prepare crackers to extend their shelf life. Nano-encapsulation was examined using transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and antioxidant activity. Ethanol and supercritical fluid-carbon dioxide (SCF-CO2) at 50 °C with ethanol as co-solvent recorded higher yield, antioxidant activities, total phenolics and total flavonoids. SCF-CO2 extracts had a higher flavonoid concentration. It was revealed that propolis nano-capsules had high-temperature stability and cytotoxic effects against the three tested human cancer cell lines (i.e. PC3, MCF7 and HePG2). The higher overall acceptability of crackers fortified with PQG was achieved with SCF-CO2 at 50 °C and ethanol extract nano-capsules, i.e. 86.57% and 86.29% respectively. The higher ability to retain antioxidant activity reduces the increase of peroxide value (PV), preventing rancidity and increasing the shelf life of crackers during the storage period. Practical application: This study can provide a suitable method for extracting bioactive compounds from propolis, and improve the biological properties and activities by nano-encapsulation, also reveals the extent of its use as a natural antioxidant and anticancer and its application in bakery products as a functional food.

Effects of low salt on lipid oxidation and hydrolysis, fatty acids composition and volatiles flavor compounds of dry-cured ham during ripening

In order to study the effect of low salt on lipid oxidation and volatile flavor of dry-cured ham, a formula containing 18% potassium lactate, 12% lysine and 70% NaCl was used as an alternative salt for curing ham. The control group using 100% NaCl as pickled formulation dry-cured ham.The results showed that low salt significantly increased peroxide value (POV) and thiobarbituric acid value (TBARS) (P < 0.05). Acid lipase, neutral lipase, and phospholipase enzyme activity, as well as the amount of free fatty acids (FFAs), were all considerably higher in the low salt group than in the full salt group (P < 0.05). The volatile flavor compounds of dry-cured ham were determined by GC-MS, and 14 differential metabolites were screened out by using OPLS-DA analysis based on P < 0.05 and VIP >1. The enrichment analysis showed that low salt mainly affected low molecules fatty acids (palmitic acid, stearic acid, linoleic acid and myristic acid). Meanwhile, low salt treatment also influenced biosynthesis of unsaturated fatty acids, linoleic acid metabolism, fatty acid biosynthesis, fatty acid elongation and fatty acid degradation. This study demonstrates that low salt promotes the formation of ham flavor quality by affecting lipid oxidation and hydrolysis.

Effect of γ-irradiation on the physicochemical and sensory properties of fresh walnut kernels (Juglans regia) during storage

The current study examined the total phenol content, antioxidant activity, sensory quality and fatty acid composition of fresh walnut kernels as a function of irradiation dose to determine dose levels that resulted in the least amount of undesirable changes to fresh walnut kernels at regular intervals of time. Fresh walnut kernels were exposed to 60Co radiation at doses of 0.5, 1.5, 3, 6, 8, and 10 kGy and stored at ± 4 °C for 28 days. Irradiation doses of 0.5 and 0.1 KGry have no significant effect on total phenol content (1.56±0.04–1.30±0.02mgGAE/g), antioxidant activity (95±0.02–85±0.01%), peroxide value (0.49±0.04–0.72±0.03%) and free fatty acid values (0.14±0.01–0.29±0.03%) respectively. However, irradiation doses of 1.0, 2.0, 3.0 and 4.0 resulted in increased peroxide values (0.89±0.02%, 0.98±0.01%, 1.05±0.01%, 1.17±0.03%), increased free fatty acid values(0.05±0.01%, 0.58±0.03%, 0.63±0.02±0.01%, 0.67±0.04%) and also the organoleptic quality were decreased (2.0 ± 0.01, 1.7 ± 0.03, 1.4 ± 0.02%, 1.2 ± 0.03%) during 28 days of storage. The use of gamma irradiation appears to be a promising technology for improving the chemical quality of fresh walnut kernels, but food safety concerns must be addressed before it can be recommended as a useful conservation alternative.

Application of nanostructured lipid carriers containing α-tocopherol for oxidative stability enhancement of camelina oil

In the present study, nanostructured lipid carriers (NLCs) were prepared using the hot homogenization method with high shear force. The optimal amounts of solid/liquid lipids ratio (glyceryl stearate/oleic acid), the aqueous phase of surfactant (tween 80/water), and α-tocopherol (αt) as constituents of NLCs were obtained using response surface methodology via Box–Behnken design and the encapsulation efficiency and loading capacity percentages of NLCs containing αt (NLCs- αt) were recorded as responses. The optimum NLCs-αt characterized in terms of particle size, particle size distribution index (PDI), scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and Fourier transfer spectroscopy infrared (FTIR) analyses. The results indicated that NLCs in the optimum point had a particle size of 198 nm and PDI of 0.28 with a spherical shape and a smooth surface. The results of DSC and FTIR analyses showed that there is no interaction between the active compounds and obtained NLCs. The release behavior of αt from NLCs-αt in the simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) revealed that the\\orsmeyer-Peppas model was the best model for the evaluation of the release kinetic of αt. It was observed that the addition of NLCs-αt reduced the DPPH radical scavenging (83.33–46.25%), TPC (228.8–169.0 mg GAE/g) and oxidative stability (4.21–3.30 h), but increased peroxide value (0.87–2.59 meqO2.kg−1), anisidine value (0.63–1.50) and TOTOX value (2.37–6.68) after 90 days of storage. Moreover, the antioxidant activity of Camelina oil containing optimum NLCs-αt (46.25%) was comparable to Camelina oil containing the TBHQ (49.45%) as a reference, but it was higher when rosemary essential oil (REO) was added with NLCs-αt (58.73%) (after 90 days of storage). In general, it can be concluded that the optimum NLCs have tremendous potential for encapsulation of αt and deliver the extraordinary antioxidant effect to Camelina oil when they are added to Camelina oil with REO.

Effect of neutralization treatment on properties of chitosan/bamboo leaf flavonoids/nano-metal oxide composite films and application of films in antioxidation of rapeseed oil

Neutralization treatment improved the slow-release antioxidant food packaging function of chitosan (CS)/bamboo leaf flavone (BLF)/nano-metal oxides composite films. The film cast from the CS composite solution neutralized by KOH solution had good thermal stability. The elongation at break of the neutralized CS/BLF film was increased by about 5 times, which provided the possibility for its packaging application. After 24 h of soaking in different pH solutions, the unneutralized films swelled severely and even dissolved, while the neutralized films maintained the basic structure with a small degree of swelling, and the release trend of BLF conformed to the logistic function (R2 ≥ 0.9186). The films had a good ability to resist free radicals, which was related to the release amount of BLF and the pH of the solution. The antimicrobial neutralized CS/BLF/nano-ZnO film, like the nano-CuO and Fe3O4 films, were effective in inhibiting the increase in peroxide value and 2-thiobarbituric acid induced by thermal oxygen oxidation of rapeseed oil and had no toxicity to normal human gastric epithelial cells. Therefore, the neutralized CS/BLF/nano-ZnO film is likely to become an active food packaging material for oil-packed food, which can prolong the shelf life of packaged food.

Application of Pomegranate Peel Extract, a Waste Agricultural Product, as a Natural Preservative in Tahini

The pomegranate peel, an agricultural by-product or waste, is a rich source of bioactive compounds. In the current study, the addition of different concentrations of pomegranate peel hydromethanolic extract (PPE) into tahini was investigated. The hydromethanolic extract of pomegranate peel in the ratio of 1 : 1 was prepared, and the PPE yield was evaluated. The HPLC and Folin-Ciocalteu methods were used to determine phenolic compounds and total phenolic content of PPE, respectively. The antioxidant activity of PPE was investigated by DPPH and FRAPS assays. Then, the different concentration of PPE (0, 0.25, 0.5, 1, and 2%) was added to tahini. Thereafter, peroxide value, TBARS, and sensory analyses were determined during 6 months of storage. The PPE yield was reported at 18.90%. Gallic acid, ellagic acid, and punicalagin were identified as the most abundant phenolic compounds in PPE. The total phenolic content, DPPH, and FRAP antioxidant assay of PPE were evaluated as 1577.65 mg/g GAE, 54 μg/ml, and 483.24 mM, respectively. It was shown that by the addition of PPE in tahini, the increase in peroxide value and TBARS was controlled. The concentrations 1 and 2% act better to inhibit lipid peroxidation. Overall, the general acceptance of samples containing 1 and 2% PPE was recorded better than other samples. The PPE showed a good function as a natural antioxidant in tahini to retard oxidation.