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旨在为米糠油的精准适度加工及其在食品工业中的应用提供科学指导，研究了常压和充氮加热（60~260 ℃）处理0~12 h条件下米糠油中谷维素及其4种主要组分〔环木菠萝烯醇阿魏酸酯（CAFA）、24-亚甲基环木菠萝烯醇阿魏酸酯（24-MCAFA）、菜油甾醇阿魏酸酯（CampFA）及 β-谷甾醇阿魏酸酯（SitoFA）〕的损失规律。结果表明：两种加热方式下谷维素及其4种主要组分的损失率随加热时间的延长均呈线性上升趋势（R2>0.90），损失速率随着加热温度升高而升高；在常压加热条件下，当温度达到220 ℃时谷维素开始快速损失，260 ℃下加热12 h时谷维素总量损失率最高（74.14%）；谷维素4种主要组分在两种热处理过程中热稳定性相似，即不高于140 ℃时各组分之间热稳定性总体无显著差异，不低于180 ℃时各组分热稳定性大小顺序为CampFA>CAFA>24-MCAFA>SitoFA；充氮加热下谷维素损失率变化趋势与常压加热下相似，但其损失率显著低于常压加热（除140 ℃和60 ℃），在220 ℃下加热12 h时两者相差最大（32.34百分点）。综上，米糠油应采用适度加工工艺及在食品工业应用中应合理控制加热条件以减少谷维素的损失，提高米糠油的营养品质。Aiming to provide scientific guidance for the precise and moderate processing of rice bran oil and its application in the food industry, the loss law of oryzanol and its four main components 〔cycloartenyl ferulate (CAFA),24-methylene cycloartenyl ferulate（24-MCAFA）,campesterol ferulate（CampFA）,β-sitosterol ferulate（SitoFA）〕 in rice bran oil heated by atmospheric pressure heating and nitrogen-filled heating respectively under the conditions of heating temperature 60-260 ℃ and heating time 0-12 h was studied. The results showed that the loss rate of oryzanol and its four main components showed a linear increasing trend with the extension of heating time (R2>0.90) under the two heating methods, and the loss rate was positively correlated with the heating temperature. Under the conditions of atmospheric pressure heating, oryzanol began to lose rapidly when the temperature reached 220 ℃, and the loss rate of oryzanol reached the highest (74.14%) when the temperature reached at 260 ℃ for 12 h. The thermal stability of the four main components of oryzanol was similar during the two heat treatment processes. There was overall no significant difference in the stability among the four components when the temperature was not higher than 140 ℃, whereas their stability was order as CampFA>CAFA>24-MCAFA>SitoFA when the temperature was not lower than 180 ℃. The variation trend of oryzanol loss rate under nitrogen-filled heating was similar to that under atmospheric pressure heating, whereas the loss rate under nitrogen-filled heating was significantly lower than that under atmospheric pressure heating(except for 140 ℃ and 60 ℃), and the difference was the highest (32.34 percentage) at 220 ℃ for 12 h. To sum up, rice bran oil should use moderate processing techniques and reasonable control heating conditions in food industry applications to reduce the loss of oryzanol, thereby enhancing the nutritional quality of rice bran oil.

为扩大棉籽油用途，提高其附加值，采用气相色谱、高效液相色谱、低场脉冲核磁共振分析仪、差示扫描量热仪、X-射线衍射仪和偏光显微镜分析了棉籽油改性后的产物棉籽油硬脂（COS）和全氢化棉籽油硬脂（FHCOS）的脂肪酸组成、甘三酯组成、SFC含量、热性质和微观结构。结果表明：COS主要由不饱和脂肪酸和非三饱和的甘三酯组成，FHCOS几乎全部由饱和脂肪酸和三饱和甘三酯组成；随温度升高，COS的SFC不断降低，FHCOS的SFC在温度高于35℃时开始降低，相同温度下FHCOS的固体脂肪含量（SFC）均高于COS的，COS在结晶和熔化过程中均有2个峰，FHCOS有1个峰，FHCOS的熔化和结晶温度均高于COS的；COS在15 ℃时无明确的晶型及稳定的结构，FHCOS为二倍链长堆积的β′晶型，结晶体为针状或棒状，结晶聚集体为类似玫瑰花状。因此，以COS和FHCOS代替棕榈油作为生产起酥油、人造奶油、黄油等的基料油具有一定的开发和应用前景。 To expand the use of cottonseed oil and increase its added value, the fatty acid compositions, triglyceride compositions, solid fat content (SFC), thermal properties and microstructure of cottonseed oil stearin (COS) and fully hydrogenated cottonseed oil stearin (FHCOS) as modified products of cottonseed oil, were analyzed by gas chromatography, high performance liquid chromatography, low field pulsed nuclear magnetism, differential scanning calorimeter, X-ray diffractometer and polarizing microscope, respectively. The results showed that COS mainly consisted of unsaturated fatty acids and non-trisaturated triglycerides, and FHCOS almost entirely consisted of saturated fatty acids and trisaturated triglycerides. The SFC of COS decreased with the increase of temperature, while the SFC of FHCOS decreased as the temperature was higher than 35℃，and the SFC of FHCOS was higher than that of COS at the same temperature, COS had two peaks in both melting and crystallization, while FHCOS had one peak, and the melting and crystallization temperatures of FHCOS were higher than those of COS. COS had no definite crystal form or stable structure at 15 ℃, while the crystal of FHCOS was double chain length-β′ type. The crystal cluster of FHCOS was needle-like or rod-like, the morphology of the aggregates of these clusters was rosette-like. The study indicated that COS and FHCOS, as a base oil replaced palm oil for the production of shortening, margarine, butter has a certain prospect for development and application.

旨在为全氢化硬脂在塑性脂肪、油凝胶等的应用提供一定的开发依据和理论基础，全面分析硬脂组成对其晶体性质的影响。测定了全氢化棕榈仁油（HPKO）、全氢化棕榈油（HPO）、全氢化棉籽油（HCSO）、全氢化大豆油（HSO）、全氢化低芥酸菜籽油（HCO）、全氢化高芥酸菜籽油（HRO）、精炼漆蜡（LW）、可可脂（CCB）的脂肪酸与甘三酯组成、热性质、微观结构及形态，研究硬脂的组成对其热性质、微观结构及形态的影响。结果表明：HPO、HCSO、HSO、HCO均以棕榈酸和硬脂酸为主，HPKO以月桂酸和豆蔻酸为主，HRO以硬脂酸和山嵛酸为主，LW以棕榈酸和油酸为主，CCB以硬脂酸、油酸、棕榈酸为主；硬脂的甘三酯组成对其熔点有很大影响，CCB、HPKO的熔化温度较低，HSO、HCO、HRO的熔化温度较高；HRO虽然含有大量的山嵛酸，但其熔化温度低于HSO和HCO，这可能与甘三酯间的相互作用有关；油脂中高熔点甘三酯含量影响油脂的固体脂肪含量曲线，相同温度下高熔点甘三酯含量高的油脂具有更高的固体脂肪含量，甘三酯间的相互作用也会影响油脂的固体脂肪含量曲线；CCB晶型为β型，HPKO、HPO、HCSO为β′型，HCO、HSO、HRO则为α型，LW为β和β′混合晶型；油脂的甘三酯组成会影响结晶聚集体的形态，高熔点甘三酯含量越高，结晶聚集体越致密有序；测定条件下（25 ℃）油脂的固体脂肪含量也会影响结晶聚集体形态。 In order to provide certain development basis and theoretical basis for the application of full hydrogenated stearin in plastic fats and oleogels, the influence of stearin composition on its crystal properties was analyzed, the fatty acid and triacylglycerols (TAGs) compositions, thermal properties, microstructure and morphology of hard fats, including fully hydrogenated palm kernel oil (HPKO), fully hydrogenated palm oil (HPO), fully hydrogenated cottonseed oil (HCSO), fully hydrogenated soybean oil (HSO), and fully hydrogenated canola oil (HCO), fully hydrogenated rapeseed oil (HRO), refined lacquer wax (LW) and cocoa butter (CCB) were determined, and the effects of composition of these stearin on their thermal properties, microstructure and morphology were investigated. The results showed that the major fatty acids of HPO, HCSO, HSO and HCO were palmitic acid and stearic acid. Lauric acid and myristic acid were the major fatty acids of HPKO. HRO was mainly composed of stearic acid and behenic acids. LW contained large amount of palmitic acid and oleic acid. The major fatty acids of CCB were stearic acid, oleic acid and palmitic acid. The melting points of these stearin were influenced greatly by their TAGs composition. The melting points of CCB and HPKO were lower relatively, and the melting points of HSO, HCO and HRO were higher. Although HRO contained a lot of behenic acid, its melting point was lower than that of HSO and HCO, which was related to the interaction of TAGs. The content of TAGs with high melting point affected the solid fat content (SFC) profile of the stearin. At the desired temperature, the higher the content of TAGs with high melting points in stearin, the higher the SFC of stearin. SFC profile of stearin was also affected by the interaction of TAGs in them. The crystals in CCB was β form,HPKO, HPO and HCSO were β′ form,HCO, HSO and HRO were α form, LW was a mixture of β and β′ form. The morphology of the crystalline aggregates was affected by TAGs composition in stearin, the higher the content of high melting point TAGs, the denser and more orderly the crystalline aggregates. The SFC of stearin under the determination condition （25 ℃） also influenced the morphology of the crystalline aggregates.

旨在为可可脂生产提供新的基料油，同时为高油酸花生油的高值化利用提供研究基础，以高油酸花生油和棕榈酸乙酯为原料，脂肪酶NS40086为催化剂，在无溶剂体系下酶法合成1,3-二棕榈酸-2-油酸甘油三酯（POP）。采用单因素实验研究反应条件对POP含量、酰基位移、sn-2位油酸相对含量的影响，并采用响应面法进行优化。结果表明：高油酸花生油酶促酯交换制备POP的最佳反应条件为反应时间3 h、底物（棕榈酸乙酯与高油酸花生油）物质的量比11∶ 1、酶添加量（以底物总质量计）3%、反应温度50 ℃，在此条件下POP含量为86.48%，酰基位移为3.25%，sn-2位油酸相对含量为72.88%。In order to provide new base oil for the production of cocoa butter and research basis for the high-value utilization of high-oleic peanut oil, with high-oleic peanut oil and ethyl palmitate as raw materials, NS40086 lipase as catalyst, 1,3-dipalmitoyl-2-oleoylglycerol (POP) was synthesized by enzymatic transesterification in a solvent-free system. The effects of reaction conditions on the POP content, acyl migration and the relative content of sn-2 oleic acid were studied by single factor experiment, and response surface methodology was used to determine the optimal reaction conditions. The results showed that the optimal reaction conditions were obtained as follows: reaction time 3 h, molar ratio of ethyl palmitate to high-oleic peanut oil 11∶ 1, dosage of enzyme 3% (based on total substrates mass), reaction temperature 50 ℃. Under these conditions, the POP content, acyl migration and the relative content of sn-2 oleic acid were 86.48%, 3.25% and 72.88%, respectively.

为促进高油酸花生油的高值化利用，在无溶剂体系中以高油酸花生油为原料，棕榈酸乙酯、硬脂酸乙酯为酰基供体，酶促酯交换合成类可可脂。以目标甘三酯1,3-二棕榈酸-2-油酸（POP）、1-棕榈酸-2-油酸-3-硬脂酸（POS）、1,3-二硬脂酸-2-油酸（SOS）含量，硬脂酸指数和酰基位移率为评价指标，在单因素实验的基础上采用响应面法对酶促酯交换合成类可可脂的工艺条件进行优化。结果表明：酶促酯交换合成类可可脂的最佳工艺条件为硬脂酸乙酯与棕榈酸乙酯物质的量比1.3∶ 1、酰基供体与高油酸花生油物质的量比12∶ 1、加酶量2.7%(以底物质量计)、反应温度60 ℃、反应时间7 h，在该条件下产物甘三酯中POP、POS、SOS的含量分别为1455%、48.87%、25.17%，硬脂酸指数为0.56，酰基位移率为7.35%。产物的目标甘三酯组成和脂肪酸组成与可可脂相近，可作为可可脂替代品应用。In order to promote the high value utilization of high oleic acid peanut oil, cocoa butter equivalent was synthesized by enzymatic transesterification using high oleic acid peanut oil as raw material, ethyl palmitate and ethyl stearate as acyl donors in a solvent-free system. Taking the contents of target triglycerides POP,POS and SOS, stearic index and acyl migration rate as evaluation indexes, the process conditions of enzymatic synthesis of cocoa butter equivalent were optimized by response surface methodology on the basis of single factor experiment. The results showed that the optimal reaction conditions were obtained as follows: molar ratio of ethyl stearate to ethyl palmitate 1.3∶ 1, molar ratio of acyl donors to high oleic acid peanut oil 12∶ 1, enzyme loading amount 2.7%(based on the mass of substrate), reaction temperature 60 ℃ and reaction time 7 h. Under these conditions, the contents of POP, POS and SOS were 14.55%, 48.87% and 25.17% respectively, the stearic index was 0.56, and the acyl migration rate was 7.35%. The triglyceride and fatty acid composition of the product are similar to those of cocoa butter, and it can be applied as the cocoa butter equivalent.

速冻专用油脂是类似于人造奶油的油包水体系的油脂混合物，主要是由基料油、乳化剂、水及其他辅料经乳化、急冷、捏合而成的一种专用油脂。速冻专用油脂是一种风味性油脂，常添加到冷冻面团中，可以改善速冻食品的风味和口感、保证速冻食品在加工和冷冻过程中品质的稳定、增强食品营养性等。分别对速冻专用油脂的概况、目前存在的问题及解决措施、基料油的改性、乳化剂的选择等进行了系统的综述，并展望了速冻专用油脂未来的发展趋势。 Fast-frozen special fat is a kind of oil mixture in water-in-oil system similar to margarine, which is mainly made of base oils, emulsifier, water and other auxiliary materials by emulsification, rapid cooling and kneading. As a kind of flavor oil, fast-frozen special fat is often added to frozen dough, which can improve the flavor and taste of fast-frozen food, ensure the quality stability of fast-frozen food during processing and freezing, and enhance the food nutrition. The general situation, existing problems and solutions, modification of base oil, selection of emulsifier of fast-frozen special fat were systematically reviewed, and the future development trend of fast-frozen special fat was prospected.

Abstract.: This study focused on the preparation of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) enriched-triacylglycerols by enzymatic interesterification using tuna oil and capric acid. The content of DHA+EPA is 26.86% in the tuna oil used in this study. A response surface methodology (RSM) was used to optimize the reaction parameters (reaction temperature, substrate molar ratio, enzyme amount and reaction time), and the optimized conditions were determined to be: reaction temperature 58 ºC, substrate molar ratio (capric acid : tuna oil) 4:1, enzyme amount 4%, and reaction time 7.5 h. Under the optimized conditions, the content of DHA+EPA in the glycerides was 40.03%, which is 13.17% higher than that in raw tuna oil. In addition, the MLM-type structured lipids containing medium chain fatty acids (capric acid) at positions sn-1,3 and a long chain fatty acid (DHA/EPA) at the position sn-2 may have many health benefits for humans. Keywords:: Capric acid, DHA, EPA, MLM-type structured lipids, Tuna oil

This study experimentally explored the effects of equivalence ratio settings on ethanol fuel combustion oscillations with a laboratory-scale combustor. A contrary flame equivalence ratio adjusting trend was selected to investigate the dynamic characteristics of an ethanol atomization burner. Research findings denote that optimizing the equivalence ratio settings can prevent the occurrence of combustion instability in ethanol burners. In the combustion chamber, the sound pressure amplitude increased from 138 Pa to 171 Pa and eventually dropped to 38 Pa, as the equivalence ratio increased from 0.45 to 0.90. However, the sound pressure amplitude increased from 35 Pa to 199 Pa and eventually dropped to 162 Pa, as the equivalence ratio decreased from 0.90 to 0.45. The oscillation frequency of the ethanol atomization burner presents a migration characteristic; this is mainly due to thermal effects associated with changes in the equivalence ratio that increase/decrease the speed of sound in burnt gases, leading to increased/decreased oscillation frequencies. The trend of the change in flame heat release rate is basically like that of sound pressure, but the time-series signal of the flame heat release rate is different from that of sound pressure. It can be concluded that the reversible change in equivalence ratio will bring significant changes to the amplitude of combustion oscillations. At the same time, the macroscopic morphology of the flame will also undergo significant changes. The flame front length decreased from 25 cm to 18 cm, and the flame frontal angle increased from 23 to 42 degrees when the equivalence ratio increased. A strange phenomenon has been observed, which is that there is also sound pressure fluctuation inside the atomized air pipeline, and it presents a special square waveform. This study explored the equivalence ratio adjusting trends on ethanol combustion instability, which will provide the theoretical basis for the design of ethanol atomization burners. [ABSTRACT FROM AUTHOR]

Corn wax, as a kind of vegetable wax, is a by‐product of the corn oil industry. In this study, the corn wax was obtained from the corn oil refineries and purified by solvent defatting and bleaching. The composition and physicochemical properties of corn wax were studied to provide theoretical guidance for the production and application of corn wax. The results showed that the purity of corn wax was higher than 95%, and the corn wax ester ranged from C42 to C58, with C46, C44, and C48 being predominant. The carbon number of fatty acids was in the range of 16–30, with a higher proportion of C20, C22, and C24. The fatty alcohols varied from C20 to C32 and were dominated by C22, C24, C30, and C23. The physicochemical properties of corn wax were also determined and compared with other vegetable and animal waxes to get a more comprehensive understanding of corn wax. The results showed that the water content, iodine number, saponification number, and melting point of corn wax were 0.03 ± 0.01%, 6.77 ± 0.85 g/100 g, 74.31 ± 3.49 mg/g and 77.28 ± 7.89°C respectively. Corn wax was a green and healthy natural resource, which has great application potential in food, health care, and medicine. [ABSTRACT FROM AUTHOR]