Abstract:The modern edible oil manufacturing technology has been developed for more than half a century in China. With the advent of a new round of scientific and technological revolution and industrial revolution, the research of new technologies of edible vegetable oil preparation and refining has attracted extensive attention. The important way to realize the industrial transformation, structural readjustment and development facilitation was through the flexible processing and accurate and appropriate processing technology of oils and greases based on the low-carbon and green manufacturing, high efficiency and low energy consumption, individualization of products, and new demands of nutrition and health. The authors briefly summarized the current research progress of novel technologies from three aspects, i.e. the oil-bearing materials pretreatment technology, the oil manufacturing technology, and the oil refining technology. The current application problems have been analyzed, and the future development trends have been prospected, providing the references of future oil technology development in China.

Abstract:Oils and fats are important nutrients. With the development of economy in China, people pay more attention to the flavor perception of oils and fats. The main factors affecting the formation of flavor variances of oils and fats include the differences in raw materials, and the oxidative degradation, thermal decomposition and Mallard reaction of oils and fats during manufacture processing. During oral processing, the taste, smell, trigeminal sensory neurons, and their interactions form the flavor recognition of oils and fats in the specific area of brain. It has been reported that receptors such as fatty acid transposase (CD36) and G protein-coupled receptor (GPCR) are participants in the perception of oils and fats. As a result, it has been suggested that the perception of oils and fats could be the sixth taste. Complex multi-sensory interactions depend on all sensory responses of human. In the future, the perception and the involvement of oils and fats in multisensory interactions should be further investigated.

Abstract:In recent years, the domestic trade volume, public attention and research popularity of butter have increased significantly. Butter development and innovation are facing the triple challenges from sensory characteristics, health quality and green ecology. This paper summarizes the butter market and research status at home and abroad, and analyzes the key directions and solutions of butter research and development in the future. The raw material innovation and technological innovation of butter in the future were particularly discussed. The review aims to provide reference for current butter production and novel butter development.

Abstract:Lipid is one of the three major nutrients needed by the human body, and its safety and health characteristics during the whole ingestion chain are highly valued. Pro-oxidation factors in the gastrointestinal tract, such as hydroxyl group, active nitrogen group, make lipids easy to generate oxidation reaction during gastrointestinal digestion. Compared with in vivo digestion evaluation, in vitro simulated digestion is the preferred method to study the gastrointestinal digestion of lipids since it is a timesaving method without ethical problems. At the same time, considering the complexity of human digestive tract environment and the diversity of lipids, the real evaluation of oxidation of lipids after digestion is particularly important. It is necessary to integrate and evaluate these methods to comprehensively explore the related problems when studying the process of digestion and oxidation of lipids in the digestive tract. The digestion process of lipids in vivo and the commonly used models of in vitro digestion of lipids were introduced. The detection methods of oxidation products during the digestion of lipids and the factors affecting the oxidation of lipids during digestion were described. It is very important to systematically study the oxidation mechanism and pathway of lipids during digestion.

Abstract:Triacylglycerols in human milk are important for infant lipid digestion and absorption. Previous research by our group has shown that human milk is naturally rich in medium- and long- chain triacylglycerols (MLCT). MLCTs are the most abundant triacylglycerols in human milk, accounting for about 30% of the total triacylglycerols, and the main structure of MLCT is a single medium chain (MLL) type triglyceride with one medium-chain fatty acid and two long-chain fatty acids. There are few medium-chain triacylglycerols (MCT) in human milk. The content, composition and influencing factors of MLCT in human milk, and the differences between human milk and infant formulas are reviewed in this paper. The digestive and metabolic characteristics of MLCT are summarized, as well as the research progress of MLCT type human milk substitute fat. The research would provide theoretical basis for the development of infant formula.

Abstract:The fatty acids composition, acid value, peroxide value (POV), 2-thiobarbituric acid value (TBA) and oil stability index(OSI) of ten kinds of vegetable oils, including camellia seed oil, shea butter oil, flaxseed oil, peony seed oil, walnut oil, grape seed oil, rose hips oil, perilla seed oil, pomegranate seed oil and sweet almond oil, were investigated. The results showed that the content of unsaturated fat oil of shea butter oil was lowest of 50.41%(mass fraction), while that of other unsaturated fat oils was higher(84.34% ~ 92.47%, mass fraction). The major fatty acid of flaxseed oil and peony seed oil was α-linolenic acid. The order of major fatty acids content of both camellia seed oil and shea butter oil was oleic acid > linoleic acid > α-linolenic acid, and that of the other six vegetable oils was linoleic acid > oleic acid > α-linolenic acid. According to the acid value, camellia oil, rose hips oil and perilla seed oil were of good quality, while that of flaxseed oil was the opposite with the lowest freshness. According to the analysis of POV and TBA, flaxseed oil was undergoing an advanced oxidation process, walnut oil mainly stayed in the primary oxidation stage, shea butter oil and grape seed oil were more susceptible to the advanced oxidation, and the oxidation degree of residual vegetable oils was not high. The OSI of shea butter was the highest while that of walnut oil was the lowest. The OSI of 10 vegetable oils was significantly negatively correlated with the mass fraction of polyunsaturated fatty acids and unsaturated fatty acids, and significantly positively correlated with the mass of saturated fatty acids and the ratio of saturated fatty acids/unsaturated fatty acids. This study could provide an experimental basis for the further development of vegetable oil products in China.

Abstract:The phenolic compounds in hemp seed oil can not only improve the antioxidant activity of oil, but also have the functions of anti-cancer, anti-inflammatory, and prevention of chronic diseases such as cardiovascular and cerebrovascular diseases. Among the four oil extraction methods of hot pressing, cold pressing, aqueous enzymatic and leaching, aqueous enzymatic process has the advantages of high total phenolic content and bright color. Therefore, this method is selected for process optimization. In this paper, Alacalase 2.4 L protease was used to hydrolyze hemp seeds and extract oil. The total phenolic content was taken as the optimization index. Three influencing factors were studied by single factor experiment including the amount of enzyme added, the ratio of solid to liquid and the pH value of enzymatic hydrolysis, and the single factor experiment was designed. The optimum process conditions were as follows: enzyme content of 4.57% (mass fraction), the ratio of material to liquid of 1g∶4.79 mL, and pH of 8.24. Under these conditions, the total phenolic content in hemp seed oil was determined to be 65.78 mg/kg. The contribution of various factors to the total phenolic content of hemp seed oil was as follows: the amount of enzyme added > pH value > ratio of solid to liquid. Oxidative damage is an important pathological factor in the development of some malignant diseases and the aging of living organisms. The synchronous growth of wild-type nematodes was treated with H2O2 solution to simulate the oxidative stress damage in nematodes, and the nematode motor deficit model was established. These nematodes were transferred to the culture medium coated with different processed hemp seed oil to investigate the effects of processing methods and main active components in the oil on nematodes. The results showed that the polyphenols in hemp seed oil could improve the behavior of C. elegans, and the order of the improvement effect was as follows: aqueous enzymatic method > hot pressing method > cold pressing method > leaching method.

Abstract:The effect of ionic liquid pretreatment on the enzyme catalytic activity was investigated to improve the synthesis efficiency of phosphatidyl-N-acetylglucosamine (PtdGlcNAc) and different imidazole ionic liquids were selected to study the transphosphatidylation of phosphatidylcholine (PC) and N-acetyl-beta-D-glucosamine (GlcNAc) catalyzed by phospholipase D (PLD). The results showed that the enzyme activity of PLD pretreated with 1-butyl-3-methylimidazole hexafluorophosphate ([BMIm][PF6]) was significantly higher than that of other ionic liquids and untreated blank groups. Therefore, [BMIm][PF6] was used as the incubation solution for PLD pretreatment. Through the optimization experiment, the optimum reaction conditions were as follows: 1 U PLD, the amount ratio of substrate PC to GlcNAc of 1∶60, cyclopentyl methyl ether as the organic phase, and the volume ratio of ionic liquid phase to aqueous phase of 4∶1. After 12 h, the product yield was 79.7%, which was 56.9% higher than that of the untreated one. PtdGlcNAc were synthesized into nanoliposomes which structures were preliminary characterized. This study could enrich the related research of PLD and provide a reference for the synthesis and application of other novel phosphatidyl compounds.

Abstract:Diacylglycerol (DAG) is an important functional lipid with functions of preventing arteriosclerosis and inhibiting fat accumulation. DAG was prepared by enzymatically catalyzed glycerolysis in a solvent-free system using glycerol and linseed oil as the raw materials and Lipozyme CALB lipase as the catalyst to improve the yield of DAG prepared from flaxseed oil and to investigate the oxidative stability of DAG. The effects of substrates molar ratio, reaction temperature, reaction time, initial water content and enzyme loading amount on DAG mass fraction were investigated by single factor experiment. The oxidation stability of DAG prepared by molecular distillation refining from flaxseed oil was studied. The results showed that the yield of DAG reached 47.13% with a purity of mass fraction up to 57.18% after molecular distillation under the molar ratio of glycerol to flaxseed oil of 20∶1 for 10 h reaction at 80 ℃ with the initial water content (mass fraction) of 0 and the enzyme loading (mass fraction) of 2.0% (calculated by mass of substrate). The oxidation stability of DAG prepared from flaxseed oil was significantly improved with the addition of TBHQ (0.20 g/L) as the antioxidant, and its theoretical shelf life was extended from 37 d to 109 d.

Abstract:Hemp seed oil composite nano-emulsion was prepared from hemp seed oil, soybean protein isolate, lecithin and kaempferol. The effects of treatment under different ultrasonic powers (100, 200, 300 W and 400 W) for 10 min on the emulsion stability were studied, and the regularity of composite emulsion stability changing with the ultrasonic conditions was revealed. The particle size, Zeta-potential, intrinsic fluorescence spectra and surface hydrophobicity were measured. It was found that under 300 W, the system uniformly dispersed due to the cavitation effect of ultrasonic treatment, the hydrophobic residues inside the protein were exposed to the surface, the internal fluorescence spectra of emulsion were red-shifted, and both the fluorescence intensity and surface hydrophobicity increased. The measurement of emulsification, creaming index and oxidation stability of the samples showed that the emulsion had good physical stability and oxidative stability under 300 W. This indicated that proper ultrasonic treatment was beneficial to improve the stability of composite system. The research results could be used for reference to prolong the shelf life of hemp seed oil and to construct a composite emulsion system.

Abstract:The antioxidant efficiency of gallic acid (GA) and its alkyl esters including ethyl gallate (GA-C2), butyl gallate, octyl gallate, lauryl gallate, hexadecyl gallate, and octadecyl gallate in walnut oil and its oil-in-water emulsion were evaluated. The determination of peroxide value (POV), conjugated dienes, thiobarbituric acid (TBA) value as well as p-anisidine value assays in walnut oil-in-water emulsion showed that the antioxidant activity of GA and its alkyl esters increased with the increase of alkyl chain length, and GA-C2 showed the strongest antioxidant activity and then descended, which was called "cut-off effect". The results of POV and TBA in walnut oil indicated that the antioxidant activity of GA and its alkyl esters tended to decrease with the increase of alkyl chain length, which was consistent with "polarity paradox". The effects of alkyl chain length on antioxidant activity of GA and its alkyl esters in different oil systems were discussed to provide basis for selecting antioxidants suitable for walnut oil and walnut oil-in-water emulsion.

Abstract:The immobilization of liquid lipase CALB was investigated, which was used to catalyze the esterification of L-ascorbic acid with stearic acid to prepare L-ascorbic acid stearate(AS). The macroporous adsorbent resin was used as the immobilized carrier for liquid lipase CALB, and the immobilization loading rate was up to 72%. The effect of different reaction variables (reaction solvent, temperature, enzyme loading amount, molar ratio of substrate, substrate concentration and molecular sieve addition amount) on the esterification was investigated and the reaction conditions were optimized. The optimal conditions were 72 ℃, 1∶12 molar ratio of L-ascorbic acid and stearic acid, 22.49% enzyme loading amount (mass fraction), and 24 h of reaction. Under the optimal reaction conditions, the maximum yield of AS was (41.33±1.81) %. The product was separated and purified, and the product was identified as AS by mass spectra. The results of Rancimat showed that AS had good antioxidant activity, and the oxidation induction period of corn oil with 100 mg/kg AS was similar to that with 50 mg/kg of TBHQ.

Abstract:The degumming of fragrant rapeseed oil was carried out using Purifine^? PLA1, Purifine^? PLC and Purifine^?3G, and the oil yield, product quality and sensory flavor of degummed fragrant rapeseed oil were systematically analyzed. The results showed that the oil yield of above three enzymatic degumming were significantly improved compared with that of the traditional hydration degumming, which could be increased by 0.47%, 0.31% and 0.52% by centrifugation, respectively, and increased by 4.32%, 2.95% and 5.77% by natural sedimentation, respectively. In terms of product quality, the phosphorus content of fragrant rapeseed oil was reduced to less than 20 mg/kg by all three degumming methods compared with that of traditional hydration degumming process with insignificant effect on the peroxide value, color value, heating test and freezing test of degummed fragrant rapeseed oil. Purifine^?PLC and Purifine^?3G had insignificant effect on the acid value of degummed fragrant rapeseed oil, while Purifine^? PLA1 could significantly increase the acid value. The variation trend of acid value and peroxide value of three enzymatic degummed fragrant rapeseed oils were consistent with that of the traditional degummed oil during storage. In the aspect of flavor, the significant differences among three enzymatic degummed fragrant rapeseed oils with the traditional degummed oils were observed after 14 d storage. The flavor of three enzymatic degummed fragrant rapeseed oils were superior to that of the traditional degummed oils based on the consumer preference analysis.