Phytochemical composition and antioxidant characteristics of traditional cold pressed seed oils in South India

Using rice bran as a press aid during the cold-pressing of sesame seeds improved the extraction yield and quality of the resultant oil

Simple, cost-effective, and practical techniques can enhance the shelf life of cold-pressed oils. This study evaluated sesame seed (SS) cold-pressed oil with various percentages of rice bran (RB) as press aid, including 0% (control or TSSO), 1% (T1), 2.5% (T2.5), 5% (T5), 7.5% (T7.5), and 10% (T10) w/w. The results demonstrated that adding RB considerably boosted extraction yields (p < .05), with 5% RB constituting the ideal combination. Adding 7.5% and 10% RB to the SS reduced free fatty acid (FFA) levels compared to the control sample. The oxidative stability index (OSI) and peroxide value (PV), however, significantly increased at combination ratios ranging from 2.5% to 10% (p < .05). Rice bran oil (TRBO) had the greatest OSI of all the studied oils, with 18.99 h, while the extracted oils showed an increase in OSI as RB contents rose. Total phenolic compounds (TPC), tocopherols, γ-oryzanol content, and total antioxidant activity (TAA) increased directly with the RB level. Despite the addition of RB altering the fatty acids concentration, linoleic and oleic acids continued to be the predominant fatty acids in TSSO, TRBO, and other extracted oil samples. Increasing the combination ratio increased the palmitic, palmitoleic, oleic, and linolenic acid content and decreased the stearic and linoleic acid content. In summary, the study demonstrated that the simultaneous cold-pressing of oil-bearing seeds and agro-industrial by-products is a potentially advantageous technique to increase the extraction yield, qualitative attributes, and shelf life of the extracted oils without the addition of synthetic antioxidants.

Elevated nitrogen fertilization differentially affects jojoba wax phytochemicals, fatty acids and fatty alcohols

Jojoba wax is gaining popularity among cosmetics consumers for its skin wound healing and rejuvenation bioactivities, attributed to collagen and hyaluronic acid synthesis. However, information regarding wax phytochemical composition and quality parameters, as well as effect of cultivation practices, and fertilization in particular, on wax quality is limited. The aim of the current work was to study the effect of nitrogen (N) availability to jojoba plants on wax phytochemical composition and beneficial skin-related contents. For this, wax quality from a six-year fertilization experiment with five N application levels was evaluated. The chemical parameters included antioxidant activity, free fatty acid, total tocopherol, total phytosterol and oxidative stability, as well as fatty acid and fatty alcohol profile. Our results reveal that the majority of wax quality traits were affected by N fertilization level, either positively or negatively. Interestingly, while fatty acids were unaffected, fatty alcohol composition was significantly altered by N level. Additionally, fruit load also largely affected wax quality, and, due to jojoba's biennial alternate bearing cycles, harvest year significantly affected all measured parameters. Results shed light on the effects of N application on various biochemical constituents of jojoba wax, and imply that N availability should be considered part of the entire agricultural management plan to enhance wax quality. Some traits are also suggested as possible chemical quality parameters for jojoba wax.

Characteristics and antioxidant activities of seed oil from okra (Abelmoschus esculentus L.)

To investigate the potential functional properties and added value of okra seed oil and provide a scientific basis for further industrial development and production of okra seed oil, its fatty acid profile, total phenolic, fat-soluble vitamin composition, mineral element composition, and antioxidant activities were examined in this study. Also, correlations between bioactive components and the antioxidant activities of okra seed oil were explored. The study results show that okra seed oil contains 12 types of fatty acids, 65.22% of which are unsaturated acids, and among these unsaturated acids, linoleic acid (43%) and oleic acid (20.16%) are two dominant acid types. Compared with walnut oil and peanut oil, okra seed oil contains relatively high total phenols, fat-soluble vitamins, and a variety of essential mineral nutrients, with a total phenolic content (TPC) of 959.65 μg/mL, a total tocopherol content of 742.71 μg/mL, a vitamin A content of 0.0017 μg/100 mL, a vitamin D content of 1.44 μg/100 mL, and a vitamin K1 content of 52.54 ng/100 mg. Also, okra seed oil exhibits better scavenging activities on hydroxyl (IC50 = 0.50 mg/mL) and ammonium salt (ABTS) free radicals (IC50 = 6.46 mg/mL) and certain reducing power (IC50 = 17.22 mg/mL) at the same concentration. The scavenging activities of okra seed oil on hydroxyl radicals and ABTS radicals, as well as its reducing power, are significantly correlated with its contents of total phenol, total tocopherol, α-tocopherol, and γ-tocopherol (p < .01). These results show that okra seed oil is rich in bioactive substances, thus presenting great nutritional potential.

Effects of Consuming Repeatedly Heated Edible Oils on Cardiovascular Diseases: A Narrative Review

Edible oils are inevitable requisites in the human diet as they are enriched with essential fatty acids, vitamins, carotenoids, sterols, and other antioxidants. Due to their nutritive value and commercial significance, edible oils have been used for food preparation for many centuries. The use of global consumption of edible oils has dramatically increased throughout the world in the 21st century owing to their incredible application in all kinds of food preparation. However, a variety of pollutants, such as pesticides, toxic chemicals, heavy metals, and environmental pollution, have contributed to the contamination of edible oils. Furthermore, the benzophenanthridine alkaloids, sanguinarine, dihydrosanguinarine, butter yellow, and other several agents are added intentionally, which are known to cause a number of human diseases. Apart from this, repeated heating and reusing of oils results in trans fats, and lipid peroxidation alters the fatty acid composition, which adversely affects the health of consumers and increases the risk of cardiovascular diseases. Moreover, the prevention of edible oil contamination in human health at various levels is inevitable to ensure consumer safety. Hence, the present review provides an overview of vegetable cooking oils and the health ailments that detection techniques are focused on.

Physico-chemical characteristics and oxidative stability of oils from different Peruvian castor bean ecotypes

The aim of this research was to assess the physico-chemical properties and shelf-life of oils press-extracted at two temperatures (60 °C and 80 °C) from five Peruvian castor bean ecotypes. A wide variation for all traits was observed. Low acidity index, low peroxide index and absence of p-anisidine were recorded. The total tocopherol contents ranged from 798 to 1040 mg/kg. A higher antioxidant capacity was detected in methanolic extracts than in hexane extract. From the Rancimat performed at 150-170 °C, the predicted shelf-life at 25 °C ranged from 0.15 to 8.93 years; the higher extraction temperature led to a longer shelf-life, probably because of enzyme inactivation.

The Effect of Different Extraction Methods on Extraction Yield, Physicochemical Properties, and Volatile Compounds from Field Muskmelon Seed Oil

Field muskmelon seed oil was extracted by press extraction (PE), Soxhlet extraction (SE), organic extraction (OSE), and aqueous extraction (AE). The oils were then evaluated for their physicochemical properties, fatty acid composition, volatile compounds, and antioxidant properties. A high yield oil was found in the SE sample. The AE sample had the highest elevated acid and peroxide values, while PE and OSE had the highest oil iodine content. The oil samples did not differ significantly in their fatty acid profile depending on the extraction method. However, E-nose, HS-GC-IMS, and HS-SPME-GC-MS showed that the flavor composition of the four samples was significantly different, attributed to the changes in the composition and content of the compounds caused by the different extraction methods. Furthermore, the strongest FRAP and the free radical scavenging ability of DPPH and ABTS⁺ showed in the SE sample. In general, SE’s seed oil has certain advantages when applied to the muskmelon seed oil industry.

Quality, Key Production Factors, and Consumption Volume of Niche Edible Oils Marketed in the European Union

Consumer’s awareness of the health-promoting aspects of food and their search for products with high nutritional value is driving increased interest in niche oils. Such oils are produced on a small scale due to limited access to raw material and its low oil content. The aim of this multi-criteria analysis was to position niche oils. Data for the study were collected based on a literature review regarding twenty-three niche oils available on the European Union market. Analysis of quality parameters, key production factors, waste reusability, and average annual consumption volume in 2015–2020 was performed. Based on the research, it was concluded that linseed (flaxseed) oil, hemp oil, mustard oil, raspberry seed oil, and sesame oil should be of the most interest to consumers. They are characterized by the highest content of tocopherols, sterols, polyphenols, and carotenoids, a favorable ratio of mono- and polyunsaturated fatty acids, and pro-ecological and sustainable production technology. Based on the results of the study, the need for empirical research was identified, the key to filling the knowledge gaps in the area of edible niche oils.