Oxidative Stability Of Oils Research Articles

Towards utilizing Asteraceae alternative oilseed species on marginal lands: Agronomic performance, fatty acid composition, oil biocompounds, and oil physicochemical properties of Asteraceae species

Including alternative and drought-resilient oilseeds in marginal lands, where conventional oilseed production is threatened, could be an effective measure to restore marginal lands and improve sustainable seed oil production. Based on this approach, the present study aimed to evaluate the potential of some new and neglected Asteraceae species as alternative oil seed crops in marginal lands. The agronomic performance, fatty acid profile, seed oil biocompounds, and physicochemical properties of blessed thistle (Cnicus benedictus), cardoon (Cynara cardunculus), milk thistle (Silybum marianum), niger seed (Guizotia abyssinica), pot marigold (Calendula officinalis) and safflower (Carthamus tinctorius) were studied under a marginal land condition (semi-dry poor soils) in two growing years. Niger seed possessed the highest oil content (39.45%), while the highest oil yield (470.21 kg ha−1) was noted in safflower. The GC and HLPC analysis indicated that all the species of seed oils were rich linoleic acid sources (51.65–73.45%). However, some species, such as safflower, also contained a high amount of oleic acid (25.41%) proportion. Pot marigold seed oils had high levels of calendic acid (more than 50% of total fatty acids). The tocopherol and phenol biocompounds as essential micronutrients for human health were abundant in the species studied, which the highest tocopherol contents recorded for blessed thistle (670.43 mg/kg) and safflower (655.75 mg/kg) oils, respectively. Accordingly, the antioxidant activity of the oilseeds followed the same trends, being the highest in blessed thistle and safflower oils. The high concentration of oleic acid in safflower oil was associated with decreasing oil density, saponification, peroxidase, and increasing viscosity indicating its high oil oxidative stability. According to agronomic and oilseed quality properties, most species, especially safflower and blessed thistle, can be considered promising alternative oilseed crops in marginal lands.

Peptidomics Analysis of Soy Protein Hydrolysates-Antioxidant Properties and Mechanism of their Inhibition of the Oxidation of Palm Olein during Frying Cycles.

This study determined for the first time the structure of the peptides (i.e., peptidomics) in soy protein hydrolysates and elucidated their effects on an oil's oxidative stability during frying cycles. The oil investigated was palm olein during 0, 4, 8, and 12 frying cycles of plantain banana chips. Proteins were extracted and hydrolyzed with two proteases. Trypsin hydrolysate (HTRY) exhibited higher anti-radical activity (DPPH, 70.2%) than the control (unhydrolyzed proteins, 33.49%) and pepsin hydrolysate (HPEP, 46.1%) at 200 µg/mL. HPEP however showed a 4.6-fold greater reduction of ferric ions (FRAP) while also possessing a higher peroxyl radical scavenging ability (716 ± 30 µM Trolox Eq/g) than HTRY (38.5 ± 35 µM Trolox Eq/g). During oil oxidative stability tests, HPEP improved the oxidative stability of the palm olein oil after 8 and 12 frying cycles, characterized by lower concentrations of hydroperoxides, and carbonyl and volatile compounds. HTRY however exerteda pro-oxidant activity. Structural data from SDS-PAGE and tandem mass spectrometry showed that the mechanism for the greater activity of the pepsin hydrolysate occurred due to unique structural features and a higher percentage of short-chain peptides. This was justified by a 25, 31, and 48% higher contents of tryptophan, histidine, and methionine, respectively (important amino acids with hydrogen atom transfer and electron-donating capacities) in the peptides identified in the pepsin hydrolysate.

Oleacein and Oleocanthal: Key Metabolites in the Stability of Extra Virgin Olive Oil.

The oxidative stability of extra virgin olive oil (EVOO) depends on its composition, primarily, phenolic compounds and tocopherols, which are strong antioxidants, but also carotenoids, squalene, and fatty acids contribute. The aim of this study was to evaluate the effect of malaxation conditions and olive storage on the composition of 'Corbella' EVOO produced in an industrial mill to determine which parameters and compounds could give more stable oils. Although a longer malaxation time at a higher temperature and olive storage had a negative effect on the content of α-tocopherol, squalene, flavonoids, lignans, phenolic acids, and phenolic alcohols, the antioxidant capacity and oxidative stability of the oil were improved because of an increase in the concentration of oleacein (56-71%) and oleocanthal (42-67%). Therefore, these two secoiridoids could be crucial for better stability and a longer shelf life of EVOOs, and their enhancement should be promoted. A synergistic effect between secoiridoids and carotenoids could also contribute to EVOO stability. Additionally, 'Corbella' cultivar seems to be a promising candidate for the production of EVOOs with a high oleic/linoleic ratio. These findings signify a notable advancement and hold substantial utility and significance in addressing and enhancing EVOO stability.

Exploitation of Cocoa Pod Residues for the Production of Antioxidants, Polyhydroxyalkanoates, and Ethanol

Cocoa pod husks (CPH) and cocoa bean shells (CBS) are the main by-products of the cocoa industry and a source of bioactive compounds. These residues are not completely used and thrown in the fields without any treatment, causing environmental problems. Looking for a holistic valorization, the aim of this work was first to deeply characterize CPH and CBS in their chemical composition, amino acid, and fatty acid profiles, as well as their application as antioxidants. CBS had a high level of protein (17.98% DM) and lipids (16.24% DM) compared with CPH (4.79 and 0.35% DM respectively). Glutamic acid and aspartic acid were the predominant amino acids. The total phenolic compounds (TPC) detected in the ethanolic extracts of CPH and CBS were similar to pyrogallol as the main detected polyphenol (72.57 mg/L). CBS ethanolic extract showed a higher antioxidant activity than CPH. Both extracts increased the oxidation stability of soybean oil by 48% (CPH) and 32% (CBS). In addition, alkaline pretreatment of CPH was found suitable for the release of 15.52 ± 0.78 g glucose/L after subsequent saccharification with the commercial enzyme Cellic®. CTec2. Alkaline hydrolyzed and saccharified CPH (Ahs-CPH) was assessed for the first time to obtain polyhydroxy alkanoate (PHAs) and bioethanol. Ahs-CPH allowed the growth of both Cupriavidus necator DSM 545 and Saccharomyces cerevisiae Fm17, well-known as PHA- and bioethanol-producing microbes, respectively. The obtained results suggest that such agricultural wastes have interesting characteristics with new potential industrial uses that could be a better alternative for the utilization of biomass generated as million tons of waste annually.

Influence of seed-roasting degree on quality attributes of sunflower oil.

To facilitate the typical flavor of sunflower oil, seed roasting is widely applied. In this study, the effects of seed-roasting degree (160, 180, 200°C for 0-25min) on the quality attributes of sunflower oil were assessed, particularly tocopherols, sterols, total phenolics, fatty acids, and triglycerides composition as essential compounds for the nutritional value of the sunflower oil. Roasting seeds at a high temperature can significantly raise oxidative stability by 1.5-1.8 times, the content of carotenoids by 2.0-5.5 times, chlorophyll by 7.5-17.0 times, as well as increase the browning index by 4.0-10.0 times and deepen the color of the sunflower oil. However, the fatty acid and triglyceride profiles of sunflower oils have little change under distinct seed-roasting degrees. Synthetically considering the various indicators measured in the current study. It is recommended that the seed roasts at 160-180°C for about 20 min to ameliorate the oxidative stability and quality. Practical Application: A well-defined roasting process is very important for the food industry to be able to produce sunflower oil with desirable nutrition, unique flavor produced by the Maillard reaction and chemical properties of sunflower oil, which changes during the roasting. Considering the flavor, peroxide values, oxidation stability, and other quality attributes of oil obtained from the roasted seed, we found that sunflower seed oil better quality is obtained when roasted at 160- -180°C for about 20 min (e.g., 160°C for 20-25 min or 180°C for 15-20 min).

The monoglyceride oleogel characteristics modified by carnauba wax

This study investigated the properties of distilled monoglyceride (DMG) and carnauba wax (CBW) oleogels at different weight ratios (100:0, 85:15, 70:30, 55:45, 40:60, and 0:100) (DMG:CBW) and two total gelator concentrations (GsC) (50 and 100 g/kg). In two-component oleogels, the presence of CBW slowed the polymorphic transition rate, reduced the releasable oil, and prevented the formation of large clusters. Both co-assembly and self-sorting gels developed in two-component oleogels. At the 85:15 ratio, the development of just mixed crystals over a long time and the formation of the eutectic system increased the oleogel properties. At high temperatures, the reduction rate of solid fat content (SFC) decreased with the increase in the CBW ratio. Bene kernel oil (BKO) considerably increased the oxidative stability of canola oil in the oleogel structure. Overall, the specific ratio of 85:15 demonstrated higher microstructure, oil binding capacity (OBC), texture, thermal, and oxidative stability properties. Moreover, the minimum extent of CBW and the formation of the eutectic system in this ratio restricted the waxy mouthfeel development.

Liposoluble vitamin B1 microcapsules: Preparation, characterization, stabilization, and bioaccessibility

AbstractThiamine (VB1) is an essential water‐soluble vitamin that is necessary in our daily diet. However, its instability when exposed to external factors poses a limitation on its application in the food industry. To address this issue and increase its application in fat‐rich food systems, this study developed liposoluble VB1 microcapsules via freeze‐drying, utilizing β‐cyclodextrin as a wall material and polyglycerol fatty acid ester as an emulsifying agent. The VB1 microcapsules were characterized in terms of their particle size distribution, morphology, solubility, and stability in soybean oil, as well as their in vitro bioaccessibility. The results showed that the average particle size of VB1 microcapsules was 83.73 μm with a nonuniform, somewhat wrinkled spherical structure. The solubility of the VB1 microcapsules in soybean oil was increased to 142.86 mg kg–1. The retention rates of VB1 in soybean oil was found to be above 95% after 48 h of UV irradiation and 96.44% after heating for 7 days at 60°C. The presence of VB1 microcapsules did not significant impact on the oxidation stability of soybean oil. The bioaccessibility of VB1 in soybean oil was 82.81%. This work provides a useful and novel direction for the application of VB1 in high‐fat diets.Practical applications: VB1 is one of the B‐group vitamins that assists in maintaining normal glucose metabolism. However, it is readily inactivated when exposed to UV radiation, certain pH conditions, and other factors. In this work, the VB1 microcapsules prepared by freeze‐drying exhibited high liposolubility, stability, and bioaccessibility, rendering them suitable for applications in oil‐based systems. This work not only provides a new delivery system to facilitate VB1 supplementation in humans, but also helps to elucidate its application prospect of VB1 in fat‐rich foods, such as edible oil, butter, margarine, rich‐fat dressings, and so on, thus improves the application value of VB1.

Influence of hot-air and infra-red pretreatments on oxidative stability, physicochemical properties, phenolic and fatty acid profile of white and black chia seed (Salvia hispanica L.) oil

In this research, the effect of hot-air (HAP) and infra-red (IRP) pretreatments at 160 and 180˚C for the time duration of 5, 10, and 15 min on the physicochemical characteristics, phenolic composition, and stability attributes of white (WCO) and black chia seed oil (BCO) were investigated. The WCO and BCO exhibited comparable physicochemical and stability characteristics while the level of phenolic compounds was higher in BCO. The phenolic acids, flavonoids, pigments, oxidative stability, Maillard reaction products, browning index, ΔE and a* value increased significantly while L*, b*, chroma and hue values decreased significantly at higher HAP and IRP exposure duration and temperature. The hydroxybenzoic (protocatechuic, vanillic, and syringic acid), hydroxycinnamic (p-coumaric, chlorogenic, sinapic, and rosmarinic acids) acids and flavonoids (epicatechin, vitexin, rutin, myricetin, luteolin, and apigenin) were highest in oil after HAP at 180°C for 15 min. The infra-red spectral information relates to oxidation and fatty acid composition of pretreated CO. HAP is more effective than IRP for improving oil yield, oxidative stability, and phenolic profile of CO.

Effect of spray drying parameters on the physicochemical properties and oxidative stability of oil from menhaden (Brevoortia spp.) and Asian swamp eel (Monopterus albus) oil extract microcapsules

This work investigated the effect of spray drying parameters on the physicochemical properties and oxidative stability of oil from menhaden (Brevoortia spp.) and Asian swamp eel (Monopterus albus) oil microcapsules. Different emulsion formulations (Maltodextrin - MD, Maltodextrin+Gum Arabic - MD+GA, and Maltodextrin+Starch - M+S), inlet air temperatures (180, 190, and 200 °C), and feed flow rates (280, 382, and 485 mL/h) were applied to microencapsulate Brevoortia spp. oil. The best operating parameters were then used to microencapsulate the Monopterus albus oil. The moisture content, MC (%), peroxide value, PV (mEq/kg), free fatty acid, FFA (%), acid value, AV (mg KOH/g) and the morphology of the microcapsules were then evaluated. The Brevoortia spp. oil microcapsules produced with the Maltodextrin+Gum Arabic emulsion formulation, inlet air temperature of 200 °C, and feed flow rate of 280 mL/h showed the lowest moisture content, peroxide value, free fatty acid, and acid value of 9.145%, 3.293 mEq/kg, 4.891%, and 2.981 mg KOH/g, respectively. Using similar parameters, the microencapsulation of the Monopterus albus oil extract recorded a moisture content, peroxide value, free fatty acid, and acid value of 8.432%, 2.713 mEq/kg, 4.911%, and 2.871 mg KOH/g, respectively. In conclusion, improved physicochemical properties and oxidative stability of Monopterus albus oil extract microcapsules were achieved using the Maltodextrin+Gum Arabic emulsion formulation and spray drying at a high air inlet temperature of 200 °C and a low feed flow rate of 280 mL/h.

Oleogelation based on plant waxes: characterization and food applications.

Fats contribute majorly to food flavour, mouthfeel, palatability, texture, and aroma. Though solid fats are used for food formulation due to the processing benefits over oils, their negative health effects should not be overlooked. Oleogelation is thus used to transform liquid oil into a gel which function like fats and provide the nutritional benefits of oils. Additionally, only food-grade gelators convert the oils into solid-like, self-standing, three-dimensional gel networks. Rice bran wax, candelilla wax, carnauba wax, and sunflower wax are mainly used plant waxes for formulating oleogels as a result of their low cost, availability, and excellent gelling ability. A comprehensive information about the wax based oleogels, their characteristics and applications is needed. The present review discusses the effect of different plant-based waxes on the properties of the oleogel formed. The article provides information on how the physical and chemical properties of waxes impact the oleogel properties such as oil binding capacity, critical concentration, rheological, thermal, textural, morphological, and oxidative stability. Moreover, the current and potential applications of oleogels in the food sector have also been covered this article.

The employment for high-density polyethylene active packages (HDPAP) bottles containing Coriandrum sativum (Corainder) essential oil in the improvement of the oxidative stability of sunflower oil

ABSTRACT In this research, the effect of high-density polyethylene active packaging (HDPAP) bottles containing Coriandrum sativum essential oil (CSEO) on the oxidation stability and sensory attributes of sunflower oil (SFO) during the accelerated storage was investigated. The migration test showed that the CSEO could migrate from the package to SFO. In the accelerated storage procedure at 65°C, the increase in the levels of acid value (AV), peroxide value (PV), p-anisidine value (AnV), thiobarbituric acid reactive substances (TBARS), conjugated dienes (K232) and conjugated trienes (K268) of SFO samples was significantly inhibited after the sunflower oil packaged by the HAPAP containing CSEO at 6000 ppm (p < .05), which showed that the HDPAP bottle containing CSEO could delay the oxidation of SFO. Therefore, the results demonstrated that employment of HDPAP bottles containing CSEO at 6000 ppm could be applied as a good replacement for the direct addition of synthetic antioxidants to the SFO.

The effect of natural antioxidant from clove (Syzygium aromaticum L.) on the oxidative stability of crude oil produced by the traditional wet rendering process of coconut (Cocos nucifera L.)

Coconut oil produced by the traditional wet rendering process may contain free fatty acids and water which lead to rancidity and shorter shelf life. Previous studies proved that cloves (Syzygium aromaticum L.), as a natural source of antioxidant eugenol, can increase coconut oil oxidation stability. This research aimed to investigate the effects of clove addition during the wet rendering process on the Peroxide Value of coconut oil and to estimate shelf life using Accelerated Shelf Life Testing (ASLT) and Artificial Neural Network (ANN). Clove powder was added into coconut milk prior to oil rendering or into coconut oil, followed by oil storage at 28, 63, and 100°C. ASLT method predicted that adding 1 g clove/kg coconut milk and 5 g clove/kg coconut oil gave the best result by improving oil shelf life from approximately 11 days (control) to 14 days, while the ANN method predicted that adding 10 g clove/kg coconut milk gave the best result by improving estimated oil shelf life to 47 days at 28oC. Coconut oil produced from clovetreated coconut milk had the best oxidative stability during storage. Activation energies and activation enthalpies of coconut oil oxidation increased due to clove addition and therefore, improved stability during storage.

Tween emulsifiers improved alginate-based dispersions and ionic crosslinked milli-sized capsules

The blending of surfactants might change the properties of alginate-based oil encapsulation preparations. Herein, the effects of Tween series (Tween 20, 40, 60, and 80) blending on the fish oil-encapsulated sodium alginate dispersions and calcium alginate capsules were studied. The results suggested Tween 80 showed better emulsifying properties than Span 80 for the alginate/surfactant emulsions. All the Tween series induced higher creaming stability than the sodium alginate-stabilized dispersion. Tween series blending did not change the sizes, decreased the water contents, and induced similar particle-like protrusions of calcium alginate capsules. Loading capacity and encapsulation efficiency of fish oil were dependent on the hydrophilic heads and fatty acid moieties of the Tween series. Tween series blending could increase the fish oil oxidative stability of the capsules. In the in vitro digestion process, Tween with saturated fatty acid moieties increased the free fatty acid release percentages. This work provided potential innovative processing technologies for improving the biological potency of fish oil.

Synthesis of triacetylferulic resveratrol ester and its assessment on the oxidative stability of fish oil during accelerated oxidative storage

A new antioxidant triacetylferulic resveratrol ester (TRE) was synthesized and characterized in the current research. The scavenging activity of TRE against 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+) free radicals was carried out by comparison with tert-butylhydroxyquinone (TBHQ), ferulic acid and resveratrol. The inclusion of TRE as an oil stabilizer in fish oil was also investigated by assessing lipid oxidation parameters such as peroxide value (POV), TBARS value and p-anisidine value (pAV) under accelerated storage conditions (12 days, 80 °C). The changes in fatty acid composition were monitored by infrared spectroscopy and gas chromatography–mass spectrometry. The results showed that the oxidation stability of fish oil supplemented with TRE was better than that of fish oil containing TBHQ, ferulic acid and resveratrol during the whole storage period. Further, the formation of oxidation products in fish oil followed a first-order kinetic model, and adding TRE effectively lowered down the reaction rate constants. Therefore, TRE can be used as a strong antioxidant for tackling oxidative processes.

Nutrient Composition, Physicobiochemical Analyses, Oxidative Stability and Antinutritional Assessment of Abundant Tropical Seaweeds from the Arabian Sea.

Foods enriched with nutritional compounds and biological activities, especially antioxidants, are considered healthier for human and/or animal consumption. Seaweeds are rich sources of biologically active metabolites and are used as functional foods. In this study, proximate compositions, physicobiochemical characteristics and oil oxidative stability were analyzed for 15 abundant tropical seaweeds (four green-Acrosiphonia orientalis, Caulerpa scalpelliformis, Ulva fasciata, Ulva lactuca; six brown-Iyengaria stellata, Lobophora variegate, Padina boergesenii, Sargassum linearifolium, Spatoglossum asperum, Stoechospermum marginatum; and five red-Amphiroa anceps, Grateloupia indica, Halymenia porphyriformis, Scinaia carnosa, Solieria chordalis). All seaweeds were analyzed for the proximate composition, including moisture content, ash content, total sugar content, total proteins, total lipids, crude fiber, carotenoid content, total chlorophyll content, proline, iodine content, nitrogen-free extract, total phenolic content and total flavonoid content. Green seaweeds showed higher nutritional proximate composition, followed by brown and red seaweeds. Among the different seaweeds, Ulva, Caulerpa, Sargassum, Spatoglossum and Amphiroa showed high nutritional proximate composition compared to other seaweeds. High cation scavenging, free radical scavenging and total reducing activities were observed for Acrosiphonia, Caulerpa, Ulva, Sargassum, Spatoglossum and Iyengaria. It was also observed that 15 tropical seaweeds contained negligible amounts of antinutritional compounds, including tannic acid, phytic acid, saponins, alkaloids and terpenoids. Nutritionally, green and brown seaweeds provided higher sources of energy (150-300 calories per 100 g) compared to red seaweeds (80-165 calories per 100 g). Additionally, this study also confirmed that tropical seaweeds improved the oxidative stability of food oils and, therefore, might be recommended as natural antioxidant additives. The overall results confirm that tropical seaweeds are potential sources of nutrition and antioxidants and may be explored as functional food, dietary supplementation or animal feed. Additionally, they may also be explored as food supplements for fortifying food products, as food toppings or for garnishing and seasoning foods. However, a human or animal toxicity analysis is required before any conclusive recommendation for daily food or feed intake can be made.

Development and characterization of walnut oleogels structured by cellulose nanofiber

Edible oleogels were successfully prepared by cellulose nanofibers (CNFs) as the unique oleogelator through emulsion-templated method at varying CNF concentrations of 0.4–4.0%, without additional thickening agent. The microstructure and physical properties of the oleogels such as oil binding capacity, rheology, texture, thermal and oxidative stability were evaluated, using a variety of tools including confocal laser scanning microscopy, polarizing light microscopy, fourier transform-infrared spectroscopy and X-ray diffractometer. The adsorption and closely packing of CNF crystals on the surfaces of the oil droplets in emulsion decreased the clustering of droplets, and inhibited the oil droplets from destabilization during drying. This formed a more reticulated and denser but less anisotropic network, contributed to a β polymorph of the lipid crystallization. Thus the oil binding capacity and stability of oleogels were greatly enhanced, while stronger gelation strength, higher hardness, lower mobility and opaque appearance of the oleogels were observed. The oil loss of oleogels after processing at cooking temperature of 90 °C was remarkably declined, while the oxidative stability of the oleogels was also improved to a satisfactory level. In summary, these results contributed to a better understanding of the oleogelation in CNF-based oleogels, and benefited the use of healthy walnut oil to develop functional fat products with desired physical properties and oxidative stability.

Effect of Ferulic Acid and Its Derivatives on Cold-Pressed Flaxseed Oil Oxidative Stability and Bioactive Compounds Retention during Oxidation

Ferulic acid (FA) is a naturally occurring phenolic antioxidant that is widely used in the food, pharmaceutical, and cosmetic industries due to its low toxicity. Its derivatives also find numerous industrial applications and may have even higher biological activity than ferulic acid. In this study, the effect of the addition of FA and its derivatives-including vanillic acid (VA), dihydroferulic acid (DHFA), and 4-vinylguaiacol (4-VG)-on the oxidative stability of cold-pressed flaxseed oil and the degradation of bioactive compounds during oxidation was investigated. The results showed that FA and its derivatives affected the oxidative stability of flaxseed oil, but their antioxidant activity depended on the concentration (25-200 mg/100 g oil) and temperature of treatment (60-110 °C). Based on Rancimat test results, flaxseed oil oxidative stability predicted at 20 °C increased linearly with ferulic acid concentration, while its derivatives effectively prolonged the induction time at lower concentrations (50-100 mg/100 g oil). The addition of phenolic antioxidants (80 mg/100 g) generally showed a protective effect against polyunsaturated fatty acids (DHFA and 4-VG), sterols (4-VG), tocols (DHFA), squalene, and carotenoids (FA). The exception was VA, which increased the degradation of most bioactive compounds. It is believed that adding properly composed mixtures of FA and its derivatives (DHFA and 4-VG) can extend the shelf life of flaxseed oil and provide nutritional benefits.

Phytochemical characterization of oil and protein fractions isolated from Japanese quince (Chaenomeles japonica) wine by-product

The wine industry generates large quantities of by-products each year. Therefore, this work aimed to isolate and evaluate the oil and protein fractions of Japanese quince (Chaenomeles japonica, JQ) press residue, offering a partial utilization of valuable bioactive compounds of wine industry by-products. To study the JQ oil extract yield, composition and oxidation stability, we modified the co-solvent composition during the supercritical CO2 (SC–CO2) extraction of oil by adding different ethanol content. The remaining defatted material was used for the isolation of proteins. The SC-CO2 extraction yielded oil rich in polyunsaturated fatty acids, tocopherols, and phytosterols. The use of ethanol as a co-solvent increased the oil yield but did not enhance its oxidative stability or content of antioxidants. We recovered protein isolate after removing tannins with 70% ethanol extraction in the next step. The JQ protein isolate contained all essential amino acids. In addition to its balanced amino acid composition, the protein isolate exhibited excellent emulsifying properties highlighting its potential as a food additive. In conclusion, JQ wine by-products can be utilized for the extraction of oil and protein fractions which can be used in food or cosmetic product formulation.

Effect of minimal neutralization at optimal conditions on minor components and oxidation stability of sunflower oil

AbstractIn this study, oxidatively stable minimal neutralized sunflower seed oils were produced using three chemicals (Ca(OH)2, MgO, and Na2SiO3) under previously determined optimal process conditions. Lipid oxidation rates at these optimum conditions were compared to the oils neutralized with NaOH (0.20%, 40°C, 15 min). It was concluded that the oils neutralized by NaOH had the shortest hydroperoxide and hexanal lag phases, thus were the least stable oils. Oils neutralized by Ca(OH)2, MgO, and Na2SiO3 had lower FFA and higher oxidative stability than oil neutralized by NaOH. The study focused on which weak alkaline has higher oxidation stability and minimum FFA content and maximum acceptable tocopherol content. The oil neutralized by Ca(OH)2 had the lowest FFA value and highest total phenolics and α‐tocopherol contents and it had better oxidative stability than oil neutralized by NaOH. It suggests that Ca(OH)2 could be more effective in producing a high quality oil.

Oxidative stability of sunflower and soybean oils enriched with black plum peel extract in comparison with synthetic antioxidants.

Black plum peel is the by-product of plum processing and is a valuable source of antioxidants and phenolic compounds. In this research, total phenolic compounds, total flavonoid content and antioxidant activity of black plum peel were measured. After that, black plum peel extract (in concentrations 0, 400, 800, 1200 and 2000 ppm) as a natural antioxidant for improving the stability of soybean and sunflower oil was used. The oxidative stability parameters of oils (peroxide value, free fatty acids, thiobarbituric acid, conjugated dienes, and carbonyl value) were measured at 60 °C for 4-16 days. Antioxidant activity, total phenolic compounds and total flavonoid content of black plum peel were 86.87% and 100.53 mg GA /g and 871.062 mg Quercetin/g respectively. Black plum peel extract could have a significant positive effect (P<0.05) on improvement of the quality and stability parameters of soybean oil and sunflower oil. The oxidative stability parameters for commercial oils and samples containing black plum peel extract were near each other and in an acceptable range. So, black plum peel is recommended as an oxidative stabilizer of oils and alternative synthetic antioxidants.