Characterization of fragrant oil extracted from pepper seed during subcritical propane extraction

Comparative Analysis of Frying Performance: Assessing Stability, Nutritional Value, and Safety of High-Oleic Rapeseed Oils

Frying is a critical process in the food industry, where selecting appropriate vegetable oils is key to achieving optimal results. In this study, French fries were fried at 175 °C with five different oils, the changes in the physicochemical indexes and free radical scavenging rate of the oils during the frying process were investigated, and the most suitable oils for frying were identified through comparative analysis using principal component analysis (PCA). We assessed the frying performances of hot-pressed high-oleic-acid rapeseed oil (HHRO), cold-pressed high-oleic-acid rapeseed oil (CHRO), soybean oil, rice bran oil, and palm oil utilizing principal component analysis over an 18 h period. The HHRO and CHRO showed lower acid values (0.31, 0.26 mg/g), peroxide values (2.09, 1.96 g/100 g), p-anisidine values (152.48, 178.88 g/mL), and total polar compound percentages (27.60%, 32.10%) than other oils. Furthermore, both the HHRO and CHRO demonstrated enhanced free radical scavenging abilities, indicative of their higher antioxidant capacities, as corroborated by the PCA results. Benzopyridine, 3-monochloropropane-1,2-diol ester, squalene, tocopherols, and polyphenol from the HHRO and CHRO during frying were compared. A comprehensive examination of harmful substances versus nutrient retention during frying revealed that the HHRO contained fewer hazardous compounds, while CHRO retained more nutrients. Therefore, this study analyzes the oxidation regulation of HHRO in frying applications, highlights the prospects of HHRO for frying in terms of health and economy, and contributes valuable insights for informed vegetable oil selection within the food industry.

Characterisation of flavourous sesame oil obtained from microwaved sesame seed by subcritical propane extraction

This study developed a novel and green method to produce fragrant sesame oil using microwaves and subcritical extraction (SBE). Sesame seeds were microwaved at 540 W for 0-9 min before subcritical propane extraction at 40 °C and 0.5 MPa. SBE caused less deformation to the cellular microstructure of sesame cotyledons while dramatically improving oil yield (96.7-97.1 %) compared to screw processing (SP) (53.1-58.6 %). SBE improved extraction rates for γ-tocopherol (381.1-454.9 μg/g) and sesame lignans (917.9-970.4 mg/100 g) in sesame oil compared to SP (360.1-443.8 μg/g and 872.8-916.8 mg/100 g, respectively). Microwaves generated aroma-active heterocyclics and phenolics faster than hot-air roasting in sesame oil with a better sensory profile. SBE had a higher extraction rate for aroma-active terpenes, alcohols, and esters while reducing the concentrations of carcinogenic PAHs and HCAs in sesame oil. The novel combination process of microwaves and subcritical extraction is promising in producing fragrant sesame oil with superior qualities.

Subcritical low temperature extraction of bioactive ingredients from foods and food by-products and its applications in the agro-food industry

Bioactive ingredients are part of the food chain and are responsible for numerous health benefits. Subcritical low temperature extraction has been employed to acquire bioactive ingredients because of its excellent properties, such as energy conservation, low temperature, elimination of residual solvent, and high extraction yield and quality. This review aims to provide a clear picture of the basics of subcritical-temperature extraction, its bioactive ingredient extraction efficiency, and possible applications in the agro-food industry. This review suggested that the extraction temperature, time, co-solvents, solid-fluid ratio, and pressure impacted the extraction efficiency of bioactive ingredients from foods and food by-products. Subcritical solvents are appropriate for extracting low polar ingredients, while the inclusion of co-solvents could extract medium and high polar substances. Bioactive ingredients from foods and food by-products can be used as antioxidants, colorants, and nutritional supplements. Additionally, this technology could remove pesticide residues in tea, concentrate edible proteins, and reduce cigarette tar. A new trend toward using subcritical low temperature extraction in extracting bioactive ingredients will acquire momentum.

Effects of Geographic Region and Cultivar on Fatty Acid Profile and Thermal Stability of Zanthoxylum bungeanum Seed Oil

Fatty acid profile and thermal stability of 7 varieties zanthoxylum bungeanum (GZF, GDJ, CJJ, SHY, SMN, SJY, GTS) seed oils (ZBO) were studied. Fatty acid profile, thermal stability were determined using gas chromatography equipped with flame ionization detector (GC-FID) and thermogravimetry analysis (TGA), respectively. Chemical properties, total phenolics and antioxidant activities of ZBO were determined as well. Palmitoleic acid and oleic acid (OA) were the dominant fatty acids, the ratio of ω-6/ω-3 polyunsaturated fatty acids (PUFA) of ZBO ranged from 0.66 ± 0.01 to 1.17 ± 0.01, seven varieties ZBO showed a higher thermal stability, with the 50% mass loss temperature ranged from 397.35 ± 4.02°C to 412.50 ± 2.35°C, GZF seed oil showed a balance fatty acid profile, the ratio of ω-6/ω-3 PUFA was 0.90 ± 0.01, GDJ seed oil showed a higher thermal stability, which the 50% mass loss temperature was 412.50 ± 2.35°C. These results suggested that fatty acid profile and thermal stability of ZBO were affected by cultivars and geographic region, and it may serve as a functional dietary oil.

Quality of Pepper Seed By-Products: A Review

Peppers are grown all around the world, usually for fresh consumption, as well as for the industrial production of different products. Pepper (Capsicum annuum L.) seeds are mostly considered a by-product. Recent investigations have shown that pepper seeds have the potential to be a valuable source of edible oil and fiber-rich flour and protein after processing. Pepper seed oil is a high-quality edible oil according to quality analysis (nutritional, chemical, sensory and antioxidant characteristics) and is suitable as an ingredient for use in the food and nonfood industries (pharmaceutical, chemical, cosmetic industries). The literature review presented in this paper revealed the high quality of two pepper seed by-products (pepper seed oil and pepper seed flour (Capsicum annuum L.)), which could guide the food industry toward new product development based on the circular bioeconomy.

Vitamin E as an essential micronutrient for human health: Common, novel, and unexplored dietary sources

Vitamin E comprises a group of vitamers that includes tocopherols and tocotrienols. They occur in four homologues according to the number and position of methyl groups attached to the chromanol ring. Vitamin E, a liposoluble antioxidant, may participate as an adjuvant in the prevention and treatment of cardiovascular, neurological, and aging-related diseases. Furthermore, vitamin E has applications in the food industry as a natural additive. In this contribution, the most recent information on the dietary sources of vitamin E, including common, novel, and unexplored sources, is presented. Common edible oils, such as those of corn, olive, palm, rice bran, and peanut, represent the most prominent sources of vitamin E. However, specialty and underutilized oils such as those obtained from tree nuts, fruit seeds, and by-products, emerge as novel sources of this important micronutrient. Complementary studies should examine the tocotrienol content of vitamin E dietary sources to better understand the different biological functions of these vitamers.

Structural Changes in Milled Wood Lignin (MWL) of Chinese Quince (Chaenomeles sinensis) Fruit Subjected to Subcritical Water Treatment

Subcritical water treatment has received considerable attention due to its cost effectiveness and environmentally friendly properties. In this investigation, Chinese quince fruits were submitted to subcritical water treatment (130, 150, and 170 °C), and the influence of treatments on the structure of milled wood lignin (MWL) was evaluated. Structural properties of these lignin samples (UL, L130, L150, and L170) were investigated by high-performance anion exchange chromatography (HPAEC), FT-IR, gel permeation chromatography (GPC), TGA, pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), 2D-Heteronculear Single Quantum Coherence (HSQC) -NMR, and 31P-NMR. The carbohydrate analysis showed that xylose in the samples increased significantly with higher temperature, and according to molecular weight and thermal analysis, the MWLs of the pretreated residues have higher thermal stability with increased molecular weight. The spectra of 2D-NMR and 31P-NMR demonstrated that the chemical linkages in the MWLs were mainly β-O-4' ether bonds, β-5' and β-β', and the units were principally G- S- H- type with small amounts of ferulic acids; these results are consistent with the results of Py-GC/MS analysis. It is believed that understanding the structural changes in MWL caused by subcritical water treatment will contribute to understanding the mechanism of subcritical water extraction, which in turn will provide a theoretical basis for developing the technology of subcritical water extraction.

Extraction and Characterization of Flaxseed Oil Obtained with Subcritical n-Butane

In this study, subcritical n-butane was adopted to extract oil from flaxseed. The extraction conditions i.e. extraction temperature, extraction time, and liquid-solid ratio were investigated and optimized by response surface methodology. The flaxseed oil obtained by subcritical n-butane were characterized and compared with those prepared by n-hexane and cold pressing. Results indicated that the optimal combination of parameters was 53.93℃, 56.82 min, and 19.98:1 mL/g. Subcritical n-butane had higher yield (28.75%) than n-hexane and cold pressing. GC analysis indicated that subcritical n-butane extraction had no obvious influence on the fatty acid composition. Nevertheless, the oil obtained by subcritical n-butane with higher contents of phytosterols (2.93 mg/g) and carotenoids (46.56 mg/kg), and presented a higher oxidation stability (9.27 h). Thus, it was suggested that subcritical n-butane extraction is a promising alternative to extract high quality flaxseed oil.