Peroxide Value Research Articles

Study on The Impact of Gelatin Coating Containing Lactobacillus acidophilus and Lactobacillus reuteri on Chicken Fillets Shelf Life

The purpose of this study is to assess how chicken fillet shelf life and sensory evaluation are affected by 1% Gelatin coating containing Lactobacillus acidophilus PTCC 1643 and Lactobacillus reuteri ATCC 1655. Probiotic-containing cultures were introduced straight to the coating solution in this investigation. Measures were taken of the chemical (pH, TVB-N, peroxide value), microbiological (Total viable count (TVC), psychrotrophic count (PTC), Enterobacteriaceae, and Pseudomonas spp.), and sensory properties. During the storage of the chicken fillet, which was kept at 4° C for intervals of 0, 3, 6, 9, and 12 days, the antimicrobial properties of the coating in the groups treated with gelatin, Lactobacillus acidophilus, and Lactobacillus reuteri were significantly (p<0.05) higher than those in the control groups, despite the fact that the results showed the highest chemical properties and sensory score across all parameters. However, gelatin + Lactobacillus reuteri and gelatin + Lactobacillus acidophilus did not differ significantly (p<0.05). Additionally, samples treated with gelatin and probiotics showed no changes in color or texture, but their odor and taste scores decreased. We draw the conclusion that gelatin is an appropriate matrix for probiotic incorporation and long-term fillet storage.

Degradation of Argan Oils Used in Edible and Cosmetic Applications After Exposure to UV Light.

This study investigates for the first time the effects of UV light exposure on the chemical composition of artisanal and cold-pressed culinary and cosmetic argan oils, as well as their quality and biological activities. We ascertained the oxidative stability of both types of oil through measurements of the peroxide value, acidity, UV-spectrophotometric indexes (E232 and E270), and iodine value. Over the course of eight hours at room temperature, the impact of UV light on the breakdown of tocopherols, polyphenols, chlorophylls, and carotenoid pigments was examined. The findings showed that during photo-oxidation, acidity, peroxide value, and particular extinction coefficients (E232 and E270) gradually increased. On the other hand, a decline in the content of polyphenols, tocopherols, carotenoid, and chlorophyll was noted. Interestingly, iodine levels failed to improve. Although after an eight-hour degradation, the physicochemical profile of Argan oils remained exceptional. DPPH• (1,1-Diphenyl-2-picrylhydrazyl) antioxidant activity tests showed a gradual decrease in radical inhibition over time, which was attributed to lower levels of tocopherol and polyphenol. However, roasted oils showed antifungal action against Botrytis cinerea fungus, while Argan vegetable oils showed no activity against Escherichia coli, Microbacterium resistens, Staphylococcus saprophyticus, and Raoultella ornithinolytica, according to antimicrobial assays.

Influence of Coated Phycocyanin on Shelf Life of Infected Penaeus semisulcatus

ABSTRACTThe present study was undertaken to evaluate the antioxidant and antimicrobial activity of chitosan‐alginate‐coated phycocyanin (PC) extract from Spirulina sp. on Penaeus semisulcatus infected with Salmonella typhimurium stored at 4°C and 8°C for 21 days. Four groups of shrimp treatments—a control sample (without infection and PC), an infected sample without PC, a non‐infected sample + PC and an infected sample + PC—were used. The toxicity test revealed no toxicity of PC against Caenorhabditis elegans. The results of the pH, thiobarbituric acid, peroxide value (PV) and total volatile basic nitrogen showed that the lowest amounts of these factors were observed in the samples immersed in PC, whereas the highest values belonged to the samples infected with Salmonella. On the basis of the total number of bacteria in food (log 10⁷ CFU/g), the shelf life of shrimps treated with PC increased by 14 and 4 days at 4°C and 8°C, respectively, compared to the control. The diphenyl‐2‐picrylhydrazyl (DPPH) and ABTS results of the antioxidant activity indicated that the highest values were observed in the infected sample + PC after 21 days at 4°C and 8°C (82.65 ± 0.36 and 89.50 ± 0.43), respectively. The results of the colour assessment showed that the highest and lowest values belonged to the control sample (without infection and PC) and the non‐infected sample with PC, respectively. The results of sensory analysis showed that the samples enriched with PC had a higher overall acceptability than samples without PC. In conclusion, PC increased the shelf life of shrimp infected with Salmonella sp.

Exploring the Potential of Pangasius Catfish Oil as a Base Oil for Nanoemulsion Products: Optimization and Characterization

Pangasius catfish, also known as striped catfish, is a high-fat fish compared to other freshwater fish like snakehead fish and carp. The oil extracted from this fish contains unsaturated and polyunsaturated fatty acids that are beneficial for health. The quality of the oil is affected by the extraction method, especially the preliminary heating temperature for the extraction. Pangasius catfish oil contains omega-3 fatty acids (EPA and DHA) that have the potential to inhibit inflammation, hyperpigmentation, accelerate skin healing for topical applications, and act as a skin permeation enhancer and oil base for nanoemulsion due to its high oleic acid content. In this research, an experimental design was conducted on pangasius catfish oil extraction using the pressing method to optimize predetermined parameters using Response Surface Methodology (RSM). The factors considered for optimization included the quantity of water and extraction temperatures, with water content ranging from 50% to 150% (w/v) and extraction temperatures ranging from 25°C to 55°C. These ranges were intended to yield results and characterization values of oxidation parameters are tested according to the International Fish Oil Standard (IFOS) through tests including Acid Value (AV), Peroxide Value (PV), Anisidine Value (p-AnV), and Total Oxidation (TOTOX). Subsequently, the optimal conditions were confirmed to obtain the best fish oil results, which were achieved at 1.5 times the amount of pre-treatment water and a pre-treatment temperature of 55°C. The pangasius catfish oil obtained from the confirmation of optimal conditions is used as a raw material for producing nanoemulsions. The D-Optimal Mixture Design of Design Expert approach is utilized to formulate the nanoemulsion. The nanoemulsion formula containing 0.5% pangasius catfish oil was determined as the optimal formula according to the range of physical characteristics of the referenced nanoemulsion preparations with a desirability value of 0.974. This study has demonstrated the potential utility of pangasius catfish oil as a prominent base oil in nanoemulsion products.

Mitigation of Oxidized Oil Effects on Production Performances and Meat Quality of Broilers by Dietary Supplementation of Allicin

The objective of this study was to evaluate the effects of dietary oxidized oil and allicin (two different dietary sources) as natural antioxidants on the growth performance and meat quality of broilers. A total of 200 one-day-old Ross 308 broilers were randomly divided into four dietary groups (50 birds/group). The experimental groups (OO—oxidized oil; OOA—oxidized oil and allicin; OOG—oxidized oil and garlic leaves) differed from the control one by the presence of oxidized oil in their dietary structure (peroxide value 9.07 (OO, OOA and OOG groups) vs. 1.70 (C group) meq active oxygen/kg). The diets given to the experimental groups differed from each other by the presence of allicin (100 mg/kg inclusion rate as extract (OOA) and 0.5% as garlic leaf powder (OOG)). At the end of the experiment, six animals/group were slaughtered, meat samples (breast and thigh) were collected, and nutritional value was established. The results showed that the allicin included in the experimental diet did not influence the proximate composition of breast meat (crude protein, fat, ash, and dry matter). The fatty acid profile was determined for each group of samples; a significant decrease in omega 3 FAs was noticed between the C group and the E groups (3.27% vs. 1.46%, 1.60%, and 1.56%) in breast meat samples, and a corresponding increase was noticed in saturated fatty acid (SFA) concentrations. Health indices with implications for atheroma and thrombus formation and cholesterol level were negatively affected by the presence of oxidized oil in the experimental diets, but the allicin extract supplement appeared to mitigate its influence. A positive influence of the dietary supplement was noticed on antioxidant capacity and polyphenol concentrations determined in breast and thigh samples under allicin supplement influence. The results of the current study revealed that the use of low oxidized oil in broilers diets did not affect productive performance. The nutritional quality of meat (breast and thigh) was negatively influenced by the presence of oxidized oil, but allicin supplements (extract or garlic leaves) improved lipid quality indices and antioxidant potential.

Identify the Purity of Sesame Oil from Sesame Seeds (Sesamum indicum L.) and Analysis Using the ATR-FTIR Method

Sesame seeds (Sesamum indicum L.) are a plant that produces the most important and oldest oil known to man. Apart from being rich in nutrients, sesame consists of important functional components such as sesamin, sesamolin, sesamol, sesaminol, sesamolin phenol, and other lignan-like active ingredients and can trigger the motive to produce sesame oil by adulteration in order to achieve market desires. The aim of this research is to identify the purity of sesame oil and analyze it using the ATR-FTIR method to detect and prevent counterfeiting. Testing the characteristics of sesame oil can be adjusted to the quality requirements that have been set, one of which is the Indonesian National Standard (SNI) so that the quality of sesame oil circulating on the market is guaranteed. This research is non-experimental research. Sesame seed oil resulting from pressing is based on the test requirements of SNI 01-4468-1998 including the physico-chemical properties test. The results of the sesame seed oil profile are that the sesame seed oil extraction yield is 29.265%, the sesame oil is bright yellow in color, has a distinctive smell, specific gravity (20oC) 0.9237± 0.0057, refractive index 1.4702 ± 0.0005, peroxide value 2 ± 0.0577 meqO2/Kg, iodine value 107.1 ± 0.5773, and acid number 0.224 ± 0.0577. Based on the research results, it can be concluded that the pressed sesame seed oil has met the requirements of the SNI 01-4468-1998 test, and from the functional groups that appear in the ATR-FTIR it can be concluded that the pressed sesame oil contains methyl ester group compounds.

Microwave-Assisted Enzymatic Green Solvent Technology for the Extraction and Characterization of Sesame Seed Oil

Traditional methods of extracting oil with organic solvents raise issues related to health, safety, and the environment. Microwave-assisted enzymatic green solvent extraction (MAEGSE) technology is environment friendly because it involves less hazardous chemical synthesis, utilizes renewable feedstock, and decreases the chemical load and emissions produced by organic solvents. The solvents methanol, ethanol, and various cell wall degrading enzymes such as hemicellulose, viscozyme L, pectinase, xylanase, and cellulase were used in this study. The MAEGSE process of sesame oil was conducted, and the results indicated that, unlike the controlled group, no enzymes were used during the process. Among all the combinations a higher oil extraction efficiency was obtained with combination of pectinase and ethanol (37.27%) followed by the xylanase with ethanol (36.75%) from sesame seed without compromising the quality of oil. Among the enzymes tested, pectinase resulted in the highest oil extraction efficiency, followed by xylanase. Use of pectinase improved the oil extraction efficiency in both ethanol and methanol mediums. The outcomes suggested that the application of pectinase enzymes plays a significant role in increasing the oil yield in comparison with the control without compromising quality of oil. Oil extracted without the use of enzyme (control) had a lower free fatty acid (FFA) concentration than the oils extracted with MAEGSE. Even though the specific gravity (SG) and refractive index (RI) of extracted oils were not significantly different in the solvents, the saponification value (SV), peroxide value (PV), iodine value (IV), and free fatty acid (FFA) were found to have minor differences among the extraction techniques.

Effect of Phycocyanin and Butylated Hydroxytoluene on the Oxidative Stability of Safflower Oil: A Comprehensive Kinetic Investigation

ABSTRACTSafflower includes both saturated and unsaturated fatty acids especially high levels of polyunsaturated fatty acid (PUFA). The addition of antioxidants during oil processing is one of the most effective methods. The aim of this research was to evaluate the oxidative stability of safflower oil supplemented with phycocyanin (PC) (200, 300, and 400 ppm), or butylated hydroxytoluene (BHT) (200 ppm), at 80, 90, and 100°C during the storage time. Oxidative stability of oil was measured through the assay of primary and secondary oxidation products: Peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) were evaluated, respectively. Results showed that the addition of PC at 300 and 400 ppm caused the lowest peroxide levels. In addition, the oxidation reactions of this oil followed a first‐order kinetic model for PV and TBARS. The amounts of PV and TBARS were dependent on the storage temperature; according to the Arrhenius equation, the activation energy (Ea) of the samples that contain 300 and 400 ppm PC decreased in all the tested temperatures compared to control. Results of the oxidative stability indicated that PC may have superior antioxidant properties than BHT and can potentially inhibit the oil oxidation. The sample containing 300 ppm PC demonstrated heightened efficacy in suppressing primary oxidation. Moreover, the results of sensory evaluation test showed that the 300 ppm PC sample received the highest rating for overall quality, which confirm that 300 ppm PC sample could be the best sample to decrease the oxidative stability in safflower oil.

Effect of Extracted Walnut Pomace Cake Edible Coating and Packaging Type on Quality Parameters of Walnut (Juglans regia L.) Kernels During Long Storage Periods

Walnuts are highly valued for their rich nutritional content, but their quality degrades during storage due to oxidation and other quality reducing processes. This study investigated the use of bioactive compounds extracted from walnut pomace, a by-product of walnut oil production, to develop an edible coating that extends the shelf life of ‘Milotai 10’ walnut kernels. Walnut kernels were stored for eight months in four different packaging materials (PE, PP, MPP, PLA) and three treatments were used (air or without treatment, nitrogen gas, and walnut pomace extract coating). The effects of these combinations on walnut quality parameters, including polyphenol content, vitamin E, fatty acids, peroxide value, and color, were analyzed. The results show that the combination of metallized polypropylene packaging under nitrogen treatment or with atmospheric air and walnut pomace extract (MPP-A-E+) best preserves walnut quality, making it a promising option for extending shelf-life.

Lipoxygenase activity in tropical fish: Changes during surimi processing and some biochemical characterization in lizardfish (Saurida tumbil).

The lipoxygenase (LOX) activity of major tropical fish used for surimi production, including threadfin bream (TB), lizardfish (LZ), and goatfish (GF), was measured in the gills, skin, and muscle. The highest LOX activity was observed in the LZ samples (p<0.05), with the gills exhibiting the greatest activity at 376.56U/mg (p<0.05). The highest peroxide value was detected in the TB samples, particularly in the gills (p<0.05). Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were the main polyunsaturated fatty acids in all the tissues and surimi. The total lipid and DHA contents of washed mince reduced considerably after the screw press process. Although LOX activity decreased during surimi production, a residual activity of 21.33U/g was observed in the finished surimi. LOX was partially purified and characterized from LZ gills. The purification was conducted using two successive chromatographic steps, Sephacryl S-200 and diethylaminoethyl (DEAE)-sepharose, resulting in a 3.52% yield and a 22.43-fold increase in purity. The optimum activity was found at 25°C and pH 7.5, with pH stability between 6.0 and 8.5. The relatively high thermal stability at 4°C-10°C suggested that LOX might contribute to fish lipid oxidation during cold storage. The enzyme was thermally inactivated at 60°C. The preferred substrate was EPA. LOX from the LZ gills was inhibited by 1mM ethylenediaminetetraacetic acid and activated by 1mM Fe2+, Na+, and Ca2+. PRACTICAL APPLICATION: Elucidating lipoxygenase activity and lipid oxidation in various tropical fish tissues, as well as understanding the characteristics of LOX, can help take appropriate postharvest actions to afford high-quality surimi.

Characterization and anti-aging activities of Haruan (Channa striata) fish oil

Haruan fish or snakehead fish (Channa striata) is a freshwater fish widely cultivated in Indonesia. Fish oils are believed to have some biological activities which are beneficial to human health, including antioxidant and antiaging activities. The objectives of this study are to determine the characteristics and yield of Haruan fish oil (HFO) using three extraction methods (steaming, maceration, and pressing), to determine radical scavenging activity (RSA) of fish oils using 2,2’-diphenyl-1-picrylhydrazyl (DPPH) radicals and 2,2'- azino-bis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radicals and to determine anticollagenase activity of HFO. The extraction of HFO from the flesh part using the steaming method resulted in the highest RSA values either using DPPH or ABTS radicals. HFO could inhibit the activity of collagenase by 26.87±0.391%. The highest yield of HFO was obtained using the steaming method, with extraction yields of flesh and offal of 2.02% and 2.05%, respectively. The acid values (AV) of HFOs obtained from different parts using the steaming method were 1.87±0.04 (flesh part), 1.88±0.07 (head) and 1.93±0.05 (offal). The saponification values (SV) of HFO using the same extraction method were 6.30±0.26, 6.17±0.07, and 6.30±0.23 for flesh, head and offal, respectively. The peroxide (PV) and iodine (IV) values were 85.37±2.86 and 198.51±7.68, 103.70±2.21 and 206.44±5.24, as well as 96.05±2.93 and 193.68±1.70, for flesh, head and offal, respectively. These parameters (AV, SV, PV and IV) met the requirements. Haruan fish oil has the potential to be developed as a source of the human diet.

Extending African walnut oil (Tetracarpidium conophorum) shelf-life by blending it with Palm, Groundnut and Avocado oils and study of their oxidative stability during accelerated storage

Oils rich in polyunsaturated fatty acids are beneficial for health. However, their high content in polyunsaturated fatty acids makes them unstable during processing which limit their application. In the food industry, hydrogenation and the addition of antioxidants are used to extend their shelf-life. However, hydrogenation leads to trans fatty acid which promote coronary heart disease, and synthetic antioxidant has been reported to be related to cardiovascular diseases, cancer etc. As solution, researchers have been looking for natural ways to preserve oils and fats by blending less stable with more stable ones or by using natural antioxidants. The objective of this study was to extend African walnut oil shelf life by blending it with palm oil, groundnut oil, avocado oil which are more stable. Palm, groundnut, African walnut and avocado oils were obtained through mechanical cold press method. Multisource edible oils were formulated using the binary model. The blends were prepared following the ratios 50:50, 60:40 and 70:30 (Palm oil/groundnut oil/avocado oil: African walnut oil). Each of the oils involved was also used at 100%. The samples were initially tested for their initial quality and stored at 65˚C for 21 days, 8 hours heating daily. Samples were withdrawn after every 7 days for analysis, by determining their peroxide, p-anisidine, TOTOX, thiobarbituric and acid values. Results showed that all the tested oil were of good quality. African walnut oil 100% was the most altered in terms of the presence of free fatty acids, primary and secondary oxidation products compared to the other oils samples and their blends. Africa walnut oil shelf life can be extended by blending it with Palm oil, Avocado oil or Groundnut oil.

Rapeseed oleosomes facilitate intestinal lymphatic delivery and oral bioavailability of cannabidiol.

Due to high lipophilicity and extensive first-pass metabolic loss, cannabidiol (CBD) has low oral bioavailability. Co-administration of CBD and long-chain lipids facilitates the intestinal lymphatic delivery, resulting in higher systemic bioavailability, as well as high levels of the drug within the intestinal lymphatic system. However, despite previous attempts with various lipid-based formulations, the oral bioavailability of CBD is still limited. In this work, we have developed a novel formulation of CBD based on natural rapeseed oleosomes. In vivo studies in rats demonstrated that oral administration of CBD-loaded rapeseed oleosomes leads to substantially higher oral bioavailability and intestinal lymphatic targeting of CBD in comparison with rapeseed oil or artificial emulsion made of rapeseed oil and lecithin. In vitro mechanistic assessments, including in vitro lipolysis and peroxide value determination suggest that the lower oxidative state of the oil in oleosomes in comparison to crude oil or artificial emulsion is likely to be the main factor responsible for the superior performance of the CBD-loaded rapeseed oleosomes in vivo. Although further investigation will be needed, the data suggest that natural seeds-derived oleosomes can be used as a promising lipid-based drug delivery platform promoting the bioavailability and lymphatic delivery of lipophilic drugs.

Purification of used Cooking Oil using a Combination of Activated Carbon and Bentonite Adsorbents

The repeated use of cooking oil at high temperatures can significantly degrade its quality, as indicated by darkened color, unpleasant odor, elevated peroxide value (PV), and free fatty acid (FFA) levels. This deterioration can contribute to health risks such as obesity, high cholesterol, heart disease, and cancer. This study investigated the effectiveness of combined activated carbon and bentonite adsorbent in reducing peroxide value and free fatty acid levels in used cooking oil. The purification method involved an adsorption process using a combination of activated carbon derived from mangosteen peel waste and bentonite. The carbonization process was carried out at 600°C for 3 hours, followed by chemical activation with H?PO? at varying concentrations of 1M, 3M, and 5M. Bentonite was activated using 5M HCl. The results demonstrated that 5 grams of activated carbon from mangosteen peel, treated with 5M H?PO?, and bentonite activated with 5M HCl, were highly effective in lowering the peroxide value and free fatty acid levels in used cooking oil. Initially, the PV of the untreated used cooking oil was 16 meq O?/kg, reduced to 3.6 meq O?/kg after treatment with the combined adsorbents. Similarly, the FFA content decreased from 2.2% to 0.09%. Both peroxide value and free fatty acid levels met the standards set by SNI 3741:2013. In conclusion, using activated carbon and bentonite is an efficient method for purifying used cooking oil, as their strong adsorption capacity effectively reduces peroxide value and free fatty acid levels.

Functional Breads with Encapsulated Vitamin C and Fish Oil: Nutritional, Technological, and Sensory Attributes

The fortification of bread is considered an effective approach for improving its nutritional properties. However, the incorporation of free bioactive components into bread formulations may affect the overall quality of breads in different ways, depending on the sensitivity of bioactive components to baking factors. In this study, the incorporation of encapsulated vitamin C (ascorbic acid and its salts) and fish oil in breads was investigated for their stability and effect on bread quality. The combination of fish oil emulsions increased the retention of encapsulated ascorbic acid, calcium ascorbate, or sodium ascorbate in breads compared to that of the free non-combined vitamin. At the same time, the combination of vitamin gels increased the retention of docosahexaenoic acid (DHA) and decreased the lipid oxidation in breads compared to the non-combined encapsulated forms. The highest retention values of ascorbic groups, eicosapentaenoic acid (EPA), and DHA were about 70%, 88%, and 95% in breads after baking, respectively. There was the negative correlation between the ABTS radical scavenging capacity and peroxide value in breads. The specific volume of breads was improved by vitamin gels but reduced by fish oil emulsions. Their combination resisted individual impact on the specific volume of breads. The breads with combined ascorbic acid gels and fish oil emulsions showed similar textural properties to the control one. The functional bread with calcium ascorbate gel and fish oil emulsion had the highest moisture content of 45.87%. The inclusion of vitamin gels plus fish oil emulsion decreased free water but increased the bound water. Combining ascorbic acid gels with fish oil emulsions effectively reduced and masked the fishy flavor. The integration of encapsulation techniques and multi-nutrient fortification is proposed as an effective way to enhance the nutritional value and quality of functional bread through synergistic effects.

Determination of rational parameters of chemical transesterification technology of sunflower oil

The object of the study is the process of chemical transesterification of sunflower oil. Liquid vegetable oils are an important component in the products of chemical, cosmetic, paint, food and other industries. Among other oils, sunflower oil is of exceptional industrial importance. Chemical transesterification technology is used to obtain oils, fats and their mixtures with specified properties required for various industries. An important task is to develop rational conditions for the oil transesterification process using a highly efficient and safe catalyst. The process of chemical transesterification of refined deodorized frozen sunflower oil according to DSTU 4492 (CAS Number 8001-21-6) using potassium glyceroxide was studied. The original oil has the following parameters: peroxide value 0.2 ½ O mmol/kg, acid value 0.1 mg KOH/g, moisture mass fraction 0.03 %, crystallization temperature –18.38 °С. The effect of transesterification parameters on the oil crystallization temperature was examined. The catalyst concentration in all experiments was 0.45 % by weight of the oil. The oil crystallization temperature was determined by differential scanning calorimetry. Rational parameters of oil transesterification were defined: temperature 110 °C, duration 1.5 hours. Under these conditions, there is a maximum increase in the oil crystallization temperature (up to –4.1 °С). The effectiveness of the rational oil transesterification parameters was confirmed by changes in the triglyceride composition by chromatography analysis. The obtained rational conditions for the chemical transesterification of sunflower oil in the presence of the potassium glyceroxide catalyst can also be used in the processes of oil transesterification with other raw materials using this catalyst.

Improved mechanical, thermal, and barrier properties of halloysite nanotubes and nanocellulose incorporated PVA-PEO films: For food packaging applications

This work presents a novel polyvinyl alcohol (PVA)-polyethylene oxide (PEO) nanocomposite with halloysite nanotube (HNT)-nanocellulose (NC) hybrid filler to tailor the mechanical, thermal, and barrier properties. PVA-PEO/ HNT-NC nanocomposites are characterized using various analytical techniques such as FTIR, XRD, TGA, DSC, and SEM. The study evaluated the impact of hybrid filler on water vapor transmission rate (WVTR), moisture retention capacity (MRC), peroxide value (POV), and mechanical properties. The simultaneous application of 3 wt% HNT and 5 wt% NC resulted in a 20 % increase in tensile strength and approximately two-fold increase in Young's modulus, with a maximum degradation temperature increase of 22° C and 16° C in the second and third stages, respectively. Compared to the pure blend, the nanocomposite exhibited a 67 % (26.7 ± 0.6 mEq/kg) improvement in oxygen barrier performance, while maintaining a low WVTR and good MRC, demonstrating their suitability for packaging applications.

Quality parameters during deep frying of avocado oil and extra-virgin olive oil

Avocado oil has a good thermal stability. However, there is a lack of knowledge about the behavior when hydrolysis is involved with oxidation processes. This study demonstrated potential for deep frying process of avocado oil. The behavior of cold-pressed olive oil and avocado oil in a domestic frying process with natural potatoes was studied. Both oils were subjected to successive frying cycles and the following chemical properties were analyzed: degree of acidity, peroxide value, p-anisidine value, total oxidation (TOTOX) value, polar compounds, total phe-nolic content, Fourier-transform infrared spectra with attenuated total reflectance, and fatty acid profile. A grad-ual increase was observed in the degree of acidity, p-anisidine, TOTOX, polar compounds but a decrease in total phenolic content during deep-frying period for both oils. It was determined that avocado oil and olive oil take 10 and 13 days of frying cycles, respectively, to reach the limit value of 25% for polar compounds. It was demon-strated that both vegetable oils are suitable for domestic frying processes, enduring a high number of deep-frying cycles before reaching the limit of polar compounds established by health regulations, despite the generation of oxidation and hydrolysis processes.

Improving sunflower oil stability with propolis: A study on antioxidative effects of Turkish propolis during accelerated oxidation.

Propolis, a natural resinous substance collected by bees, is known for its potent antioxidant properties. This study investigates the antioxidant activities and total phenolic contents of propolis samples from 16 provinces of Türkiye and their effects on the oxidative stability of sunflower oil. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) inhibition was in the range of 28.1%-92.5% in thirteen propolis samples, whereas this rate was 24.5% in butylated hydroxytoluene (BHT). Although 2,2'-azino-bis(3-ethylbenzotiazolin-6-sulfonic acid) (ABTS) value was 224µmol trolox/g in BHT, this value was in the range of 262-1370µmol trolox/g in propolis samples, except for one. Propolis methanol extracts 13 applied to sunflower oil at a concentration of 1000ppm were more efficient than BHT added at 200ppm for inhibiting the production of peroxide value (PV). Similarly, most propolis extracts (1000ppm) demonstrated antioxidant activity against the production of p-anisidine (p-AV) in sunflower oil under accelerated oxidation conditions. It was determined that Turkish propolis had strong antioxidant properties and delayed oxidation and may be utilized commercially in the food sector to delay the oxidation of fats and oils.

Fish oil-containing edible films with active film incorporated with extract of Psidium guajava leaves: preparation and characterization of double-layered edible film.

The utilization of zein and gum arabic has grown in an attempt to formulate wall materials based on protein-polysaccharide complexes. This mixture provides a versatile delivery system for hydrophilic (guava leaf extract, GLE) or lipophilic (fish oil, FO) bioactive compounds, and it can be used as an edible film-forming polymer. This study was undertaken to characterize FO-containing edible films that were double-layered with a film containing GLE. Modified zein and gum arabic solutions (MG complex) were mixed at a ratio of 1:1.5 (v/v), adjusted to pH 5, added with glycerol (20% of the complex) and FO (5% of the complex), and finally adjusted to pH 5. This was prepared as the bottom/lower layer. The upper/active layer was prepared by mixing MG complex, glycerol, and GLE (1, 3, and 5% w/v of the complex). The total phenolic and flavonoid contents in GLE were 15.81 mg GAE/g extract and 6.99 mg QE/g extract, respectively. The IC50 of the DPPH radical scavenging activity of GLE was 26.86 ppm with antibacterial activity against Bacillus subtilis and Escherichia coli of 9.83 and 12.55 mm. The total plate counts of double-layered films containing GLE were retained below 3 log CFU/g during 28-day storage. The peroxide values of these films were dimmed for no more than 9.08 meq/kg sample on day 28 of storage. Thickness (872.00-971.67 μm), water vapor transmission rate (12.99-17.04 g/m 2/day), tensile strength (1.56-2.02 kPa), elongation at break (61.53-75.41%), glass transition (52.74-57.50°C), melting peak (131.59-142.35°C), inhibition against B. subtilis (33.67-40.58 mm), and inhibition against E. coli (2.05-9.04 mm) were obtained by double-layered films. GLE can be successfully incorporated into the active layer of a double-layer film to improve its characteristics while significantly slowing down the microbial contamination and oxidation rate. MG complex and FO can also contribute to the performance of the edible film.