Grasas y Aceites

Evaluation the kinetic of peroxide and hexanal formation in ascorbyl palmitate incorporated sunflower oil during accelerated oxidation

P. Kavran — 2024-03-25

The effects of temperature (40-80 °C), time (0-28 days), and different concentrations (0-1000 mg/kg) of ascorbyl palmitate (AP) on peroxide value, conjugated diene, triene acids and hexanal contents in sunflower oil kept under accelerated oxidation conditions have been evaluated. Samples with added AP showed lower peroxide values and hexanal contents than their counterparts without AP. While with increasing temperature, the reaction orders for peroxide formation reduced from first to zero order, those for hexanal formation were found to be first order under different experimental conditions. AP reduced the reaction rate constant for peroxide and hexanal formation. The activation energy required for peroxide and hexanal formation ranged from 14.64-89.40 and 1.62-12.14 kJ/mol K, respectively. 400 mg/kg AP, providing the highest activation energies for peroxide and hexanal formation, was found to be the best concentration to enhance the oxidative stability of sunflower oil under defined conditions.

Cold-pressed tiger nut (Cyperus esculentus L.) oils: chemical and aromatic profiles, sensory properties, and consumer preferences

E. Keskin Uslu — 2024-03-14

In this study, tiger nut oils produced by cold pressing were characterized by means of physicochemical, compositional, and sensory analyses. The major fatty acids were oleic (70.4%), palmitic (13.3%), and linoleic (11.9%) acids. The main sterols were β-sitosterol and stigmasterol (58.3 and 20.5 mg/100 g), and the main tocopherol was α-tocopherol (234.78 μg/g). Syringic acid, apigenin and vanillin were the major phenolic compounds quantified. The cold-pressed oils crystallized at -9.12 °C and melted at -1.87 °C. A sensory panel described the oil with 5 sensory descriptive (almond, nutty, roasted, straw, sweety, soil) terms. A consumer test indicated that appearance, smell/aroma, and taste/flavor scores were above 4.0 on a 5-point hedonic scale. In conclusion, tiger nut oils with retained nutrients and specific aroma could be produced by the cold-pressing technique. Further studies for food and functional food applications of this gourmet oil are anticipated.

Quality attributes of oil extracted from hazelnuts treated with gaseous ozone

A.S. Demirci — 2024-03-15

In this study, the impact of ozonation on hazelnut oil quality was investigated. Hazelnuts were exposed to gaseous ozone at different concentrations (3.3 and 10 mg·L⁻¹) and exposure times (30, 60, and 120 min). The fatty acid value and composition remained unchanged. β-sitosterol, campesterol, and ∆5-avenasterol contents were unaffected. With increasing ozone levels and exposure times, there was a slight rise in peroxide value and γ-tocopherol, and a decrease in α-tocopherol. The total phenolic content and antioxidant activity were lower in oil extracted from hazelnuts which had been ozonated for more than 60 min at both doses, compared to the control. Overall, the quality and composition of hazelnut oil remained stable with ozone treatments, depending on the treatment conditions.

Variability in seed quality traits in castor germplasm

L. Velasco — 2024-03-22

Castor is an industrial oilseed crop with great potential for biorefineries. However, little is known about the variability in the bioactive compounds in castor germplasm. This study evaluated seed weight, oil content, fatty acid profile, tocopherols, and phytosterols in 160 accessions of the USDA-ARS castor germplasm collection. The accessions were grown in Cordoba, Spain, under three different environmental conditions. Environmental and genotype-by-environment interaction effects were predominant for most traits, resulting in moderate to low broad-sense heritabilities, which ranged from 0.12 for total tocopherol content to 0.88 for hundred-seed weight. The genetic variability in the seed quality traits identified in the collection was lower than that reported previously for the germplasm of wild and semi-wild accessions from Spain, which is attributed to the lower genetic diversity in cultivated than in wild forms. The variation in seed quality traits in castor germplasm can be exploited to improve the concentration of bioactive compounds in castor cultivars.

How does harvest time affect the major fatty acids and bioactive compounds in hazelnut cultivars (Corylus avellana L.)?

Hüseyin İrfan Balık — 2024-03-14

This study was conducted to investigate the effects of harvest time on the protein, oil, fatty acids and bioactive compounds in hazelnut cultivars (Corylus avellana L. cvs. ‘Tombul’, ‘Palaz’, ‘Çakıldak’, ‘Okay 28’ and ‘Allahverdi’). The harvest was carried out at 7 different periods with weekly intervals from 20 July to 31 August. As the harvest time progressed, increases and decreases were detected in protein, oil, fatty acids and bioactive compounds. The highest oil content was measured in the H5 and H6 harvest periods. The highest content was determined in H3 for oleic acid. Higher total phenolics, total flavonoids and antioxidant activity were obtained in the first 3 harvest periods than in the other periods. The present findings revealed that the protein, fatty acids and bioactive compounds in hazelnut cultivars may differ according to the harvest time. The results obtained will provide clearer ideas to both the industry and the producers about the optimum harvest time for the intended use of these cultivars.

Effect of edible coating containing Aloe vera extracts on the oxidative stability and quality parameters of cooked ground chicken meat

G. Yılmaz — 2024-03-15

This study investigated the impact of incorporating Aloe vera gel (AVG) and Aloe vera leaf skin (AVLS) extracts into edible coating (EC) on retarding lipid oxidation and enhancing the quality characteristics of cooked ground chicken meat during 14 days of storage at 4 °C. The results indicated that both AVG and AVLS extracts had a similar amount of total phenolic contents. EC application resulted in a decrease in pH values, and an increase in aw values. The addition of 2% AVG or AVLS extracts into EC formulation also decreased TBARS and ORP values. Although textural properties were not affected by EC application containing AVG or AVLS extracts, this application retarded L^*, a^*, and b^* color values. The results indicated that Aloe vera extracts may be incorporated into EC by processors to improve lipid oxidation inhibition and maintain the quality characteristics of poultry meat products during refrigerated storage.

Quinoa seed: A source of lipophilic nutraceuticals for the prevention of metabolic syndrome in a rat model

S. Y. Al-Okbi — 2024-03-22

Metabolic syndrome (MS) is a cluster of metabolic changes including hypertriglyceridemia, elevated glucose tolerance and fatty liver. The aim of this research was to study the bioactivity of petroleum ether extracts prepared from quinoa 1 and Hualhuas quinoa in a MS rat model. Fatty acids and α-tocopherol were assessed in the extracts. MS was induced by feeding a high fructose-high fat diet (HFFD). Four groups of rats were assigned: the control group, fed a balanced diet; the control group, fed a HFFD diet; and two test groups, fed on a HFFD diet and treated by either quinoa 1 or hualhuas extract. The Glucose tolerance, plasma lipids, oxidative stress biomarkers, liver lipids and histopathology of the liver and heart were assessed. The results showed that extracts from both quinoa varieties had the potential to prevent MS; although quinoa 1 was more effective. In both varieties, the major fatty acid was linoleic. Hualhuas showed a higher percentage of linolenic acid than quinoa 1; while more alpha-tocopherol was present in quinoa1.

Research progress on the genesis and removal methods of non-hydratable phospholipids from vegetable oils

F.G. Pan — 2024-04-10

Vegetable oil phospholipids can be divided into hydratable phospholipids (HP) and non-hydratable phospholipids (NHP). The general process of alkali refining or hydration degumming can remove most of the phospholipids, and the rest is mainly non-hydratable phospholipids. A non-hydratable phospholipid has obvious hydrophobicity, which cannot be completely removed even after 16 times of washing, so the non-hydratable phospholipid is the main research target of vegetable oil degumming. In order to better understand and study the non-hydratable phospholipids, the chemical composition and origin of non-hydratable phospholipids in vegetable oil are discussed. The advantages and disadvantages of these various detection and removal methods are analyzed in this paper.

Synergistic antibacterial effects of Trachyspermum ammi L. essential oil and sodium nitrite in combination on artificially inoculated food models

T. Malik — 2024-04-01

The addition of carminative essential oils could be an approach for food preservation and would minimize or substitute chemical preservatives. In the present study, essential oils (n=11) namely, Anethum sowa, Cinnamomum zeylanicum, Citrus bergamia, Cymbopogon flexuosus, Cymbopogon martini, Cymbopogon winterianus, Elettaria cardamomum, Mentha arvensis, Ocimum basilicum, Salvia sclarea and Trachyspermum ammi, were screened against Aeromonas hydrophila and Listeria monocytogenes. The largest diameters of zone of inhibition, 19.9 ± 0.33 mm and 21.7 ± 0.58 mm, were exhibited by T. ammi essential oil against Aeromonas hydrophila and Listeria monocytogenes, respectively. Growth inhibition studies for T. ammi essential oil, sodium nitrite and their combinations were also carried out on cucumber, apple, gram flour soup and mutton broth models. The combination of T. ammi essential oil and sodium nitrite depicted synergism and was also effective in reducing the bacterial counts in artificially inoculated food systems.

Microwave-assisted transesterification of sour cherry kernel oil for biodiesel production: comparison with ultrasonic bath-, ultrasonic probe-, and ohmic-assisted transesterification methods

M. T. Golmakani — 2024-04-10

In this study, sour cherry kernel oil was converted to biodiesel by microwave-assisted transesterification. Evaluations were made of several variables, namely, reaction time (1, 2, 3, 4, and 5 min), microwave power (100, 200, 300, 400, and 500 W), methanol/oil mole ratio (3, 6, 9, 12, and 15), and catalyst (KOH) concentration (0.3%, 0.6%, 0.9%, 1.2%, and 1.5%). The efficiency of fatty acid methyl esters increased in response to lengthier reaction times, greater microwave power, higher methanol/oil mole ratio, and higher catalyst concentrations up to the optimal level. The optimal reaction conditions for microwave-assisted transesterification were 300 W microwave power, 1.2% catalyst concentration, a methanol/oil mole ratio of 1:2, and a reaction time of 4 min. Microwave-assisted transesterification was more effective than ohmic-, magnetic stirrer-, ultrasonic probe-, and ultrasonic bath-assisted transesterification methods. In conclusion, microwave-assisted transesterification can be suggested as a fast, efficient, and economical method compared to other transesterification methods.

Evaluation of monthly changes in essential oil yield and components of cherry laurel (Prunus laurocerasus L.) leaf

S. Akçura — 2024-03-14

This research was carried out to examine the monthly changes in both the volatile oil content and volatile components of cherry laurel leaves by taking samples every month for 12 months in Turkey. Harvest periods significantly affected volatile oil content (P < 0.01). Depending on harvest periods, volatile oil ratios ranged from 0.19 to 0.35%. The months of August, July, and September yielded the highest volatile oil ratios. Benzaldehyde, phenol, benzoic acid, benzeneacetonitrile, pentadecanone, 1,54-dibromotetrapentacontane and, tetrapentacontane were determined as components in the volatile oil. The ratio of benzaldehyde, the main active ingredient, varied between 83.89 and 94.41%, depending on the harvest time. The cherry laurel leaf should be harvested in July, August, and September for high essential oil ratios and in May, June, and July for high benzaldehyde ratios. Due to the high concentration of benzaldehyde in its volatile oil, cherry laurel evergreen leaf can be considered a valuable source of raw materials for the fragrance and pharmaceutical sectors.

Effect of different lysozyme treatments on the properties of Kashar cheese properties

A.D. Karaman — 2024-03-25

In this study, the solid and liquid forms of microbial lysozyme and egg lysozyme were added to kashar cheese for a 90-day period, and the physicochemical and microbiological features of the cheese were examined. The physicochemical (pH,% LA, DM, fat, protein, TN, WSN, OI, salt), textural, and microbiological characteristics of the cheese were compared to those of control samples (TMAB, coliform, yeast-mold, lactobacilli, spore microorganism, E. coli). Information on free fatty acids (FFA) and volatile compounds was also evaluated. The results showed that goods treated with various lysozyme forms had better physicochemical, microbiological, and textural qualities during the ripening period and decreased microbial loads. The study’s findings highlight and suggest employing lysozymes, particularly in microbial form, to increase the shelf life of Kashar cheese and to improve the quality and safety of cheese, as well as obtain better quality characteristics during storage.

Extraction of amaranth seed oil using subcritical butane and use of the generated cake for protein extraction

P.A. Rivas-Torrico — 2024-04-01

The purpose of this research was to determine the technical feasibility of extracting amaranth seed oil with butane in a subcritical state and to take advantage of the cake generated. To this end, a type of non-germinated grain was characterized, oil was extracted from a germinated grain and the characterized one, the oil obtained was characterized, and the protein was extracted from the defatted cake of the non-germinated one. It was found that the non-germinated grain was made up of 13.33% protein, 7.24% fat, and 9.02% moisture, the optimum yield of this grain was 91%, for the germinated grain, a maximum value of 6.63% for oil mass. By comparing the characteristics of both oils, higher quality was found in the non-germinated oil, and the maximum protein extraction productivity was 5.15%. Thus, it has been concluded that this extraction method is technically feasible.