Preparation of high-quality concentrated fragrance flaxseed oil by steam explosion pretreatment technology

Lipidomic analyses of five Carya illinoinensis cultivars

Carya illinoinensis (Wangenh.) K. Koch, nuts are a renowned health food. However, there are many cultivars of this nut tree, and their mature kernel lipid composition has not been thoroughly studied. Therefore, we used liquid chromatography-mass spectrometry (LC-MS) to analyze the lipid composition of mature nuts of five C. illinoinensis cultivars. In the mature kernels of all cultivars, there were 58 lipid types which were mainly composed of glycerolipids (c. 65%) and phospholipids (>30%). Triacylglycerol (TG) accounted for the largest proportion of mature nuts of all cultivars, exceeding 50%; and diacylglycerol (DG), ceramide (Cer), phosphatidylcholine (PC), and phosphatidylethanolamine (PE) were also relatively high. Additionally, nuts contain fatty acids, mainly oleic, linoleic, and linolenic acids. Our research provides a new perspective for the processing and utilization of plant and edible oils, and for the use of C. illinoinensis kernels in the development of medicine and food science.

Optimal Hydrothermal Treatment of Sesame Seeds to Retain Most of the Nutrients

Sesame oil is an important source of nutrients. Thus, there is a need to develop new technologies, which preserve the integrity of these substances in processed oil. The aim of the study was to outline the optimal hydrothermal treatment of sesame seeds, which would enable preserving its therapeutic properties. White sesame seeds were used as raw materials. They were treated with infrared radiation (900 watts per 1 m²), followed by hydrothermal treatment. Infrared treatment decreased the seed moisture content of 10-16% by 1.5-2.0 times. A range of important compounds was preserved after treatment, such as fatty acids (ranging from 5 to 45%, depending on the type of compound). The following fatty acids were found in the oil composition: linoleic (40-43%), palmitic (7%), stearic (5%), and oleic (43-45%). In addition, vitamin E was found (130 mg per 100 g). The oil can be stored for long periods as it contains trace amounts of water and dissolved oxygen.

Characteristics and Antioxidant Activity of Walnut Oil Using Various Pretreatment and Processing Technologies

This study was the first time the effects of pretreatment technology (microwave roasting, MR; oven roasting, OR; steaming roasting, SR) and processing technology (screw pressing, SP; aqueous enzymatic extraction, AEE; subcritical butane extraction, SBE) on the quality (physicochemical properties, phytochemical content, and antioxidant ability) of walnut oil were systematically compared. The results showed that the roasting pretreatment would reduce the lipid yield of walnut oil and SBE (59.53−61.19%) was the processing method with the highest yield. SR-AEE oil provided higher acid value (2.49 mg/g) and peroxide value (4.16 mmol/kg), while MR-SP oil had the highest content of polyunsaturated fatty acid (73.69%), total tocopherol (419.85 mg/kg) and total phenolic compounds (TPC, 13.12 mg/kg). The DPPH-polar and ABTS free radicals’ scavenging abilities were accorded with SBE > AEE > SP. SBE is the recommended process for improving the extraction yield and antioxidant ability of walnut oil. Hierarchical cluster analysis showed that processing technology had a greater impact on walnut oil than pretreatment technology. In addition, multiple linear regression revealed C18:0, δ-tocopherol and TPC had positive effects on the antioxidant ability of walnut oil, while C18:1n-9, C18:3n-3 and γ-tocopherol were negatively correlated with antioxidant activity. Thus, this a promising implication for walnut oil production.

Influences of microwave exposure to flaxseed on the physicochemical stability of oil bodies: Implication of interface remodeling

This study aimed to investigate the influences of microwave (MV) exposure to flaxseed on the physicochemical stability of oil bodies (OBs) focused on the interface remodeling. The results showed that the intracellular OBs subjected to absolute rupture and then partial dispersion by protein bodies visualized by TEM following MV exposure (1-5 min; 700 W). After aqueous extraction, native flax OBs manifested excellent spherical particles with completely intact surface and wide particle size distribution (0.5-3.0 μm) examined by cryo-SEM. Upon 1-5 min of MV exposure, the defective interface integrity and beaded morphology were successively observed for flax OBs, accompanied by the impaired physical stability and rheological behavior due to the newly assembled phospholipid/protein interface. Notably, the profitable migration of phenolic compounds effectively suppressed the lipid peroxidation and protein carbonylation in flax OBs. Thus, MV exposure (1-5 min; 700 W) was unfavorable for improving the physical stability of flax OBs.