Chemical properties and oxidative stability of Arjan ( Amygdalus reuteri ) kernel oil as emerging edible oil

Effects of Hot Air, Vacuum, and Conductive Drying on the Fatty Acid Profile of Cucurbita maxima Pulp and Its Processing By-Products

Considering the short shelf life of fresh pumpkin due to its high water content and the extensive use of dried pumpkin in the food industry, it is necessary to find an efficient drying method that minimizes water activity and preserves nutritional properties. In this study, the effects of hot air drying (HAD), vacuum drying (VAD), and conductive drying (CD) at 50, 60, and 70 °C on fatty acid profiles were investigated to determine optimal drying conditions that preserve fatty acid (FA) quality and associated nutritional benefits. Results showed that drying methods had a significant effect (p < 0.05) on fatty acid composition and yield, resulting in different amounts of palmitic, oleic, linoleic, and linolenic acids as major FAs compared to fresh pulp. The saturated FA content was higher in CD pulp (up to 42.37%), followed by HAD and VAD. Oleic acid, as the most important representative of monounsaturated FAs, came from VAD (up to 30.64%). Linoleic and linolenic acid, as the most important polyunsaturated FAs of the omega-6 and omega-3 fatty acids, were found in higher proportions in CD pulp at 50 and 60 °C (up to 31.12%) and HAD pulp at 60 and 70 °C with an airflow velocity of 1.5 m/s (up to 39.70%). In addition, the peel and seeds, the by-products resulting from the processing of the fruit pulp, were also evaluated with regard to the fatty acid profile. Two fractions also contained the four major FAs in representative amounts, indicating their valuable reuse.

Oxidative stability and nutritional quality of stored Linum usitatissmium L. and Argania spinosa L., oil blends: Chemical compositions, properties and nutritional value

Identification of the chemical compositions of fatty acids and tocopherols shows the high content of linum usitatissimum oil (LO) by linolenic acid 55.3735% and γ-tocopherol 570.927 mg/kg, while argania spinosa oil (AO) is known by the dominance of oleic acid 47.77% followed by linoleic acid 31.08% as well as tocopherols by γ-tocopherols 687.485 mg/kg and δ-tocopherols 51.035 mg/kg. This difference in compositions enables us to enrich the low-stability oil and monitor its behavior during storage at a specific time and under specific conditions. In this study, pure linum usitatissimum and argania spinosa oils extracted by cold pressing as well as their formulations at proportions of (LO: AO) respectively: (80:20; 60:40, 50:50; 40:60; 20: 80) were oxidized at 60 °C for 28 days of storage, during which time the pure oils and blends were assessed for oxidative stability by studying their different fatty acid and tocopherol profiles and physicochemical characteristics such as acidity, peroxide value and chlorophyll and carotenoid pigments, as well as nutritional indexes such as the atherogenic index (AI), the thrombogenic index (TI), and the hypocholesterolemic: hypercholesterolemic ratio (HH), ω3:ω6 ratio, also the oxidative susceptibility (OS), and oxidazability value (Cox), and total phenolic compounds (TPC).

Ostrich oil as a fat substitute in milk-based infant formula

In this study, the possibility of replacing vegetable fats with ostrich oil in infant formula (IF) production was investigated. The fatty acid profile, the positional distribution of fatty acids in the triacylglycerols, the cholesterol content, and the physicochemical properties of ostrich oil were determined and compared with breast milk fat and vegetable oils. In the next step, two infant formulas were produced using ostrich oil and vegetable oils and the physicochemical properties, rheological properties, color parameters, and sensory analysis of the resultant powders were compared. The results showed that the predominant fatty acids in ostrich oil are palmitic acid, oleic acid, and linoleic acid which is similar to breast milk fat and vegetable oils. The presence of appropriate cholesterol content in ostrich oil makes it more similar to breast milk fat compared to vegetable fats. Palmitic acid was located at sn-2 position in 15% triacylglycerol from ostrich fat, which was equal to the amount reported for vegetable fats. The incorporation of ostrich oil in infant formula production showed that there is no statistically significant difference between quality attributes of powder formulated with ostrich oil or vegetable oils. Therefore, ostrich oil can be introduced as a new source of edible oil, and addition of ostrich oil is an effective way to reduce the gap between the composition of breast milk and infant formula.

Reduction in Five Harmful Substances in Fried Potato Chips by Pre-Soaking Treatment with Different Tea Extracts

Thermally processed food always contains various types of harmful substances. Control of their levels in food is important for human health. This work used the extracts from green tea dust, old green tea, yellow tea, white tea, oolong tea, and black tea to simultaneously mitigate diverse harmful substances in fried potato chips. The six tea extracts (30 g/L) all showed considerable inhibitory effects on the formation of 5-hydroxymethylfurfural (reduced by 19.8%-53.2%), glyoxal (26.9%-36.6%), and methylglyoxal (16.1%-75.1%). Green tea and black tea extracts exhibited better inhibitory abilities than the other three teas and were further investigated for other harmful compounds by various concentration treatments. Finally, pre-soaking of fresh potato slices in 50 g/L extracts of green tea dust displayed, overall, the most promising inhibitory capacity of HMF (decreased by 73.3%), glyoxal (20.3%), methylglyoxal (69.7%), acrylamide (21.8%), and fluorescent AGEs (42.9%) in fried potato chips, while it exhibited the least impact on the color and texture. The high level of catechins in green tea dust may contribute most to its outstanding inhibitory effect, whereas the distinguished inhibitory effect of black tea extract was speculated to be attributable to the high levels of theaflavins and amino acids in the fully fermented tea. This study indicated that green tea dust, a predominant waste of the tea industry, had great potential to be exploited to improve food quality and safety.

Different effect of chemical refining process on Baneh (Pistacia atlantica var mutica) kernel oil: Regeneration of tocopherols

The present study was conducted to investigate the impact of refining process on the chemical properties (fatty acid composition and tocopherols, sterols, and polyphenolic contents), qualitative parameters (peroxide value, acid value, and p-anisidine value), and antioxidant activity (DPPH radical scavenging assay and FRAP test) of Baneh (Pistacia atlantica var mutica) kernel oil. The results revealed that the refining process had no significant effect on the fatty acid composition. A major finding of this research was the increase in the tocopherol and sterol content up to the bleaching stage followed by their decrease in the deodorizing phase. Some tocopherol and sterol compounds in crude oil were dimerized or attached to other compounds by ester bonding, which are released during some stages of the refining process and this factor is responsible for their increase. In fact, during this process, these compounds are regenerated. The occurrence of this phenomenon in the refining process improved the DPPH radical scavenging power of Baneh kernel oil up to the bleaching stage. Moreover, the content of phenolic compounds decreased after refining of Baneh kernel oil, and only in the deodorizing stage, an increase of these compounds was observed. In general, the results of this study showed that the refining process had a completely different effect on the antioxidant compounds (especially tocopherols) compared to other oils.

The Use of Salvia macrosiphon and Lepidium sativum Linn. Seed Gums in Nanoencapsulation Processes: Improving Antioxidant Activity of Potato Skin Extract

In the present study, the effect of Salvia macrosiphon Seed Gum (SMSG) and Lepidium sativum Linn. Seed Gum (LSSG) as a coating agent on the properties of nanoencapsulated potato skin extract was studied. Moreover, the antioxidant effect of nanoencapsulated extract at a concentration of 1000 ppm incorporated into soybean oil was evaluated. The Z-average size of the emulsions stabilized by SMSG; LSSG; and a complex (1 : 1) of SMSG and LSSG (CSL) was estimated as 160.2, 144.3, and 115.2 nm. The encapsulation efficiency of phenolic extracts in the powders formed by SMSG, LSSG, and CSL was 82.39, 81.67, and 93.6% which declined to 45.28, 48.22, and 62.67% after storage for 40 days at 30°C. The results indicated that the use of coating agents for encapsulation enhanced their antioxidant effect and compared with TBHQ and free extract that nanoencapsulated extract by CSL had the highest antioxidant activity followed by LSSG nanoencapsulated extract and SMSG nanoencapsulated extract.

Development of walnut oil and almond oil blends for improvements in nutritional and oxidative stability

For the increase in oxidative stability and phytonutrient contents of walnut oil (WO), 5, 10, 20 and 30% blends with almond oil (AO) were prepared. The fatty acid compositions and the micronutrients of the oil samples such as tocopherol, phytosterol and squalene were measured by GC-MS and HPLC. It was found that the proportions of PUFAs/SFAs in blended oils with high AO contents were lowered, and the blends contained higher levels of tocopherols, phytosterols and squalene than those of pure WO. The 60 °C oven accelerated oxidation test was used to determine the oxidative stability of the blended oil. The fatty acid composition, micronutrients and oxidation products were determined. The results showed that the oxidation stability of the blended oil increased with an increasing proportion of AO. In addition, a significant negative correlation between micronutrient and oxidation products was observed as the number of days of oxidation increased.

Incorporation of the nanoencapsulated polyphenolic extract of Ferula persica into soybean oil: Assessment of oil oxidative stability

In the present study, for the first time, the biological activities of Ferula persica extract (FPE) coated with locust bean gum (LBG) and chitosan in W/O/W emulsions were investigated. Based on the findings, the Z-average size of emulsions coated by chitosan, LBG, and the complex of chitosan and LBG (1:1) (CCL) was 115.47, 128.37, and 68.12 nm, respectively. The encapsulation efficiency of the phenolic extracts in the powder produced by chitosan, LBG, and CCL decreased from 85.3 to 64.1, from 89 to 71.4, and from 93.3% to 77.9% during 24-day storage, respectively. Also, the application of the coating in the encapsulation of FPE increased the antioxidant efficacy in soybean oil while compared with tert-butylhydroquinone (TBHQ) and un-encapsulated FPE. In this regard, The FPE nanoencapsulated by CCL showed the best antioxidative activity in soybean oil, followed by the FPE of nanoencapsulated by LBG and chitosan, respectively, which can be correlated with higher levels of polyphenolic compounds release over time in the sample coated with CCL. In this context, the encapsulation with CCL can be proposed as a promising technique to improve the antioxidant activity of extracts.

Chemical compositions and antioxidant activity of adlay seed (Coixlachryma-jobi L.) oil extracted from four main producing areas in China

Adlay oil (AO) is an important component of adlay seeds that has many beneficial functions to human health. In this study, the variations in the chemical composition and antioxidant activity of AOs extracted from adlay samples obtained from four main producing areas of China were first investigated. Results revealed that the AO of the adlay samples varied from 7.398 ± 0.486% to 8.464 ± 0.725%. The highest contents of total fatty acid, triolein, total phenolic, and total flavonoid were observed in Xingren AO, whereas coixol content was found to be highest in Pucheng AO. The AO samples were grouped successfully in accordance with the origins by partial least squares-discriminant analysis and hierarchical cluster analysis based on the contents of the chemical components. Furthermore, AOs exhibited considerable levels of 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity (IC₅₀ , 0.924 ± 0.113 to 1.116 ± 0.109 mg/mL) radical scavenging activity, ferric-reducing antioxidant power (FRAP) activity (EC₅₀ , 0.019 ± 0.002 to 0.028 ± 0.002 mg/mL) activity, and β-carotene-linoleic acid bleaching activity (IC50, 0.233 ± 0.008 to 0.414 ± 0.012 mg/mL) activity. Total phenolic and total flavonoid both demonstrated highest correlation with ABTS values (r = -0.952 and r = -0.960, respectively). The results derived from above studies suggest that geographic origin has a certain influence on the phytochemical profiles and antioxidant activity of the AOs. PRACTICAL APPLICATION: The chemical composition and antioxidant activity of adlay oils extracted from the adlay samples obtained from four main producing areas of China were evaluated, including total fatty acid, triolein, total phenolic, and total flavonoid, and ABTS radical scavenging activity, FRAP activity, and β-carotene-linoleic acid bleaching activity.

First Study on the Oxidative Stability and Elemental Analysis of Babassu (Attalea speciosa) Edible Oil Produced in Brazil Using a Domestic Extraction Machine

Interest in edible oil extraction processes is growing interest because the final nutritional quality of the extracted oil depends on the procedure used to obtain ir. In this context, a domestic cold oil press machine is a valuable tool that avoids the use of chemicals during oil extraction, in an environmentally friendly way. Although babassu (Attalea speciosa) oil is economically important in several Brazilian regions due to its nutritional and healthy features, few studies have been conducted on the chemical composition and stability of babassu oils extracted by cold pressing. Babassu oil's major constituents are saturated fatty acids (~86.42%), with the most prevalent fatty acids being lauric (~47.40%), myristic (15.64%), and oleic (~11.28%) acids, respectively, within the recommended range by Codex Alimentarius, presenting atherogenicity and thrombogenicity indexes favorable for human consumption. Peroxide value, Rancimat, and TGA/DSC results indicated that babassu oil is stable to oxidation. Also, macro- (Na, K, Ca, Mg, P) and micro-elements (Fe, Mn, Cr, Se, Al, and Zn) of babassu oil were determined, revealing levels below the tolerable upper intake level (ULs) for adults. These findings demonstrated that cold-press extraction using a domestic machine yielded a high-quality oil that kept oil chemical composition stable to oxidation with natural antioxidants.

Antioxidant activity of Pistacia atlantica var mutica kernel oil and it's unsaponifiable matters

In this research, antioxidant activity of Pistacia atlantica var mutica (a wild type of pistachio in Iran) kernel oil (PAKO) and unsaponifiable matters of kernel oil (UKO) were compared with those of sesame seed oil (SSO) and rice bran oil (RBO) as well as with their unsaponifiable matters (USO and UBO) and α-tocopherol (natural antioxidant) was selected as control. Also, some chemical properties such as (FRAP, DPPH radical-scavenging, rancimat and oven assays (peroxide value and carbonyl value) were assessed. The amount of unsaponifiable matters of studied oils was between 1.4 and 3.5%. The highest total phenolics was observed in SSO (1024 mg/kg), followed by RBO, and PAKO was 174, and 75 mg/kg, respectively. In DPPH radical-scavenging assay, the EC₅₀ values of PAKO, SSO, RBO, UKO, USO, UBO, and α-tocopherol were determined as 38.9, 50, 48.4, 14, 12.7, 15.9 and 61.4 mg/mL, respectively. In FRAP assay, the highest value was nominated for UKO (434 mmol/L); followed by USO, UBO, PAKO, SSO, RBO and α-tocopherol (404, 357, 364, 298, 210 and 58 mmol/L; respectively). Also, considering the results of oven test, the incorporation of UKO into pure sunflower oil resulted in the highest oxidative stability; followed by UBO, USO, PAKO, SSO, RBO and α-tocopherol. According to results of the rancimat test, the incorporation of unsaponifiable matters (UKO, USO, and UBO) resulted in the highest oil/oxidative stability index (OSI) in pure sunflower oil, followed by oils studied (PAKO, SSO, and RBO). According to results, UKO had the highest antioxidant activity, followed by USO, UBO, PAKO, SSO, RBO, and α-tocopherol.