亚麻籽油微胶囊的制备及理化性质研究

为减缓亚麻籽油中不饱和脂肪酸的氧化,该实验利用喷雾干燥技术,用大豆蛋白、麦芽糊精作为壁材,亚麻籽胶充当乳化剂,对亚麻籽油进行包裹,制备微胶囊,并对微胶囊产品进行理化指标的测定。结果表明:微胶囊产品含油率为38.03%,表面油含量为4.76%,包埋率达到87.50%,水分含量为1.30%,产品干燥,流动性好;颗粒分布均匀,基本呈球体;常温下溶解度良好;吸水性实验表明,产品易吸水,影响产品品质。     

亚麻籽油微胶囊的工艺优化及稳定性研究

采用正交试验对亚麻籽油微胶囊的制备工艺条件进行优化,以包埋率为指标,根据单因素试验结果,设计4因素3水平试验,确定最佳工艺条件为固形物浓度15%、芯壁材质量比1∶1.5、亚麻籽胶添加量1.6 g/500mL、进风温度180℃,经验证试验表明包埋率可达86%以上。产品经过TG和DSC分析表明,当温度达到190℃时产品发生热分解,热稳定性良好,基本可以满足一般食品加工条件。加速储藏试验表明,经过包埋的亚麻籽油的过氧化值变化缓慢,产品稳定性较好,达到保护油脂的目的。     

Encapsulation of α-tocopherol in protein-based delivery particles

Two types of proteins, including β-lactoglobulin (BLG) and hen egg white protein (HEW), were examined for their ability to encapsulate α-tocopherol (α-TOC) after salt-induced gelation of the proteins. Parameters affecting encapsulation efficiency were investigated including the type of salt, as well as concentrations of salt, protein, and α-TOC. Concentrations of protein and α-TOC revealed to have an influence on encapsulation efficiency. The optimum preparation condition of BLG-encapsulated α-TOC was as follows: BLG of 0.5% (w/v); α-TOC of 100 mM; and CaCl₂ of 25 mM. The optimum preparation condition of HEW-encapsulated α-TOC was as follows: HEW of 4.0% (w/v); α-TOC of 50 mM; and ZnCl₂ of 25 mM. With the selected preparation conditions, encapsulation efficiency by BLG aggregates was approx. 20% and that by HEW was approx. 32%. From the in vitro estimation, the release of α-TOC was nearly 100% in simulated gastric condition. Alginate was therefore used for coating of these encapsulated particles to prolong the release of α-TOC till simulated intestinal condition. The α-TOC of approx. 55% and 38% were retained and released in the simulated intestinal condition from BLG- and HEW-encapsulated particles, respectively.     

Microencapsulation of flaxseed oil in flaxseed protein and flaxseed gum complex coacervates

Flaxseed oil, a rich source of omega-3 fatty acids, was microencapsulated in a novel matrix formed by complex coacervation between flaxseed protein isolate (FPI) and flaxseed gum (FG). This matrix was crosslinking with glutaraldehyde. Liquid microcapsules with three core (oil)-to-wall ratios (1:2, 1:3 and 1:4) were prepared and spray-dried or freeze-dried to produce powders. The microencapsulation efficiency, surface oil, morphology and oxidative stability of these microcapsules were determined. The spray-dried solid microcapsules had higher oil microencapsulation efficiency, lower surface oil content, smoother surface morphology and higher oxidation stability than the freeze-dried microcapsules. The highest microencapsulation efficiency obtained in spray-dried microcapsules was 87% with a surface oil of 2.78% at core-to-wall ratio 1:4 and oil load 20%. The oxidation stability obtained from spray-dried microcapsules at core-to-wall ratio of 1:4 was nearly double that of the unencapsulated flaxseed oil.     

Encapsulation efficiency and oxidative stability of flaxseed oil microencapsulated by spray drying using different combinations of wall materials

This study aimed at evaluating the potential of maltodextrin combination with different wall materials in the microencapsulation of flaxseed oil by spray drying, in order to maximize encapsulation efficiency and minimize lipid oxidation. Maltodextrin (MD) was mixed with gum Arabic (GA), whey protein concentrate (WPC) or two types of modified starch (Hi-Cap 100^TM and Capsul TA®) at a 25:75 ratio. The feed emulsions used for particle production were characterized for stability, viscosity and droplet size. The best encapsulation efficiency was obtained for MD:Hi-Cap followed by the MD:Capsul combination, while the lowest encapsulation efficiency was obtained for MD:WPC, which also showed poorer emulsion stability. Particles were hollow, with the active material embedded in the wall material matrix, and had no apparent cracks or fissures. During the oxidative stability study, MD:WPC combination was the wall material that best protected the active material against lipid oxidation.     

亚麻籽油的热稳定性研究

通过加热试验,研究了亚麻籽油的热稳定性。结果表明:在高温加热条件下,亚麻籽油中α-亚麻酸含量有所降低,总反式脂肪酸的含量提高;在200℃和250℃条件下保持120 min后,亚麻籽油中α-亚麻酸的含量分别下降了6.1%和57.7%,总反式酸的含量分别为4.47%和20.89%。说明亚麻籽油作为烹调用油,烹调温度在200℃以下比较合适,加热时间不宜过长。     

Characteristics of flaxseed hull oil

Oils from two commercial flaxseed hulls extracted by six procedures were evaluated for physicochemical characteristics. Oil yield ranged from 9% to 28% depending on solvent and extraction. Lipid fractionation of crude flaxseed hull oil yielded 92.5% neutral lipids, 3.1% phospholipids, 2.4% acidic lipids and 2.1% free fatty acids. Flaxseed hull oil exhibited three thermal transitions between −35 and −13 °C with solvent dependent polymorphism. Thermal oxidation by differential scanning calorimetry (DSC) revealed three step oxidation of flaxseed hull oil with mean onset and oxidation temperatures at 121 and 150–253 °C, respectively depending on the extraction procedure. Flaxseed hull oil exhibited two-fold difference (0.6–1.2 μm Trolox equivalent/g) in antioxidant activity measured by a photochemiluminescence (PCL) assay. Supercritical CO₂ extracted the most oil with the highest antioxidant capacity of all evaluated procedures resulting in a defatted flaxseed hull containing the highest (53 mg/g) secoisolariciresinol diglucoside (SDG) level.     

Antioxidant activity of flaxseed oil

Effective concentration of antioxidants and its reactivity toward peroxil radicals (constant k7) have been measured by the chemiluminescence technique for flaxseed oil. Effective concentration of antioxidants is shown to depend on the technology of producing flaxseed oil; period of seed storage before use; and storing duration of flaxseed oil also. Minor component content of flaxseed oil, which may be the members of antioxidant pool, has been quantitatively estimated.     

制取高不饱和度亚麻籽油的方法研究

以亚麻籽油为原料,采用干法分提对其进行了分离改性,进一步分离出富含高不饱和脂肪酸的亚麻籽油。研究了搅拌速率、冷却速率、养晶时间、结晶温度对亚麻籽油液态油得率、碘值的影响。得到最佳的工艺条件为:搅拌速率15 r/min,冷却速率4℃/h,养晶时间12 h,结晶温度-8℃。在最佳工艺条件下所得液态油碘值(I)为198 g/100 g,液态油得率为89.2%。通过分析样品油与成品油的脂肪酸组成、含量和0℃固体脂肪含量发现,成品油的饱和脂肪酸和固体脂肪含量较样品油明显降低。     

炒籽温度对压榨亚麻籽油品质的影响

采用不同温度对亚麻籽进行炒籽并压榨制油,对压榨亚麻籽油的感官品质、理化指标及营养成分进行分析,研究炒籽温度对压榨亚麻籽油品质的影响。结果表明:随着炒籽温度的升高,压榨亚麻籽油的气味从坚果芳香过渡到严重焦糊味,色泽加深,在195℃炒籽45 min时形成热榨亚麻籽油特有的浓香型风味;营养成分如VE、总酚以及甾醇含量随炒籽温度升高而逐渐减少,在255℃炒籽45 min时,3种营养成分的损失率分别为75. 7%、76. 5%和88. 9%;酸价、过氧化值、茴香胺值、K232值、K270值随炒籽温度升高而增加,且炒籽温度对压榨亚麻籽油中主要脂肪酸含量有显著影响;适当炒籽对压榨亚麻籽油的氧化稳定性是有利的;高温炒籽压榨亚麻籽油中的营养成分含量与其理化指标密切相关,进而共同影响压榨亚麻籽油的品质。     

山核桃油微囊的制备及稳定性研究

采用复凝聚法制备山核桃油微囊,以包油率为指标,以阿拉伯胶用量、明胶用量、山核桃油添加量、固化剂用量、p H为考察因素,在单因素实验的基础上,通过正交实验确定山核桃油微囊的最优处方为:阿拉伯胶用量10%,明胶用量15 m L,山核桃油添加量0.6 m L,固化剂添加量6 m L,p H为4.0。制备的微囊平均包油率为83.9%±0.24%,经倒置显微镜法观察其形态规则,分布均匀,采用Malvern激光粒度仪测定平均粒径为1.423μm,Zeta电位值为-38.2 m V。稳定性实验结果表明制备的微囊在高温、强光照下包油率稳定,有利于进一步加工贮藏。      

新疆胡麻油香气萃取条件研究

采用HS-SPME（顶空固相微萃取）方法对新疆伊亚3号胡麻油脂挥发性香气成分进行了萃取。通过优化固相微萃取的条件,建立了胡麻油香气组分萃取的方法。结果表明,采用50/30μm DVB/CAR/PDMS萃取头,在磁力搅拌条件下,萃取温度60℃、萃取时间40min时胡麻油中的挥发性风味物质能最大程度地挥发、吸附。      

Characterisation of ice cream containing flaxseed oil

Five batches of a 12% (w/w) fat ice cream formulation were prepared using different amounts of flaxseed oil (0%, 3%, 6%, 9% and 12% w/w) to replace milkfat. Meltdown rates, texture of ice cream, particle size of fat globules and microstructure of the ice cream were determined. Increasing the proportion of flaxseed oil in ice cream resulted in an increase in the meltdown rate and a decrease in the ice cream hardness. These were attributed to the low melting temperature of flaxseed oil and the varying extent of fat flocculation. In ice cream containing a high proportion of milkfat, the fat globules formed large particles largely due to flocculation rather than partial‐coalescence. The extent of fat flocculation decreased as the proportion of flaxseed oil was increased. Evidence of fat coalescence was observed in ice cream containing 12% flaxseed oil. The fat flocculates stabilised the air cells and strengthened the foam structure of the ice cream.     

亚麻籽油抗动脉粥样硬化作用的研究进展

研究表明ω-3脂肪酸能够降低心血管疾病的发生危险,其生物学和分子效应能够调节动脉粥样硬化的形成和发展,包括对炎症反应、血小板功能、血压、甘油三酯水平及动脉粥样斑块稳定性的调节作用。ω-3脂肪酸包括α-亚麻酸、二十碳五烯酸和二十二碳六烯酸。亚麻籽油含有丰富的多不饱和脂肪酸,是α-亚麻酸最丰富的来源之一。此外,有研究表明亚麻籽油可有效减缓动脉粥样硬化的发展。主要对亚麻籽油抗动脉粥样硬化作用的研究现状进行综述,以期为研究亚麻籽油对动脉粥样硬化的改善作用提供理论参考。     

丁香油微胶囊的制备及表征

以明胶和海藻酸钠为壁材,采用复凝聚法对丁香油进行包覆,通过喷雾干燥法得到干燥的微胶囊产物,研究pH、明胶和海藻酸钠质量比、芯壁质量比、壁材用量、搅拌转速对微胶囊形成的影响,并对微胶囊的缓释性进行研究,采用红外、TG、SEM对优选实验条件下制备得到的微胶囊进行表征.结果表明:经过微胶囊化的丁香油挥发性明显降低,热稳定性大...     

薄荷油微胶囊的制备及其性能研究

目的研究薄荷油微胶囊的制备方法,并研究包合物的制备及其结构表征,开发新型微胶囊载香技术。方法通过紫外分光光度法对短葡聚糖链(octenyl succinic anhydride short chain dextran chain, OSA-SGC)包埋薄荷油的包埋率进行测定,通过扫描电子显微镜(scanning electron microscope,SEM),热重分析(thermogravimetric analysis,TGA),红外光谱分析(infrared spectroscopy,IR)及X射线衍射(X-ray diffraction,XRD)对OSA-SGC及其包合物进行表征。结果由酶解蜡质玉米淀粉制备的OSA-SGC聚合物的包埋率为35.7%。结论酶解蜡质玉米淀粉制备的OSA-SGC聚合物能够有效包埋薄荷油,为新型微胶囊载香技术的开发与应用找到新出路。     

水酶法提取胡麻籽油的工艺研究

以胡麻籽为原料,采用复合酶酶解技术对胡麻籽油进行提取,考察了预处理方法、粉碎时间、酶的种类、复合酶复配比例及复合酶添加量对胡麻籽油提取率的影响,在前期实验的基础上,采用中心组合设计,对液料比、酶解pH、酶解温度及酶解时间进行了响应面优化。结果表明:高压高温湿热法预处理,胡麻籽在10 000 r/min转速下粉碎90 s利于胡麻籽油的提取;最佳复合酶制剂组成为中性蛋白酶与戊聚糖酶质量比2∶1,复合酶的最适添加量为1.2%(以脱壳胡麻籽质量计);响应面优化的最适工艺参数为液料比9.19∶1、酶解pH 5.94、酶解温度53.62℃、酶解时间3.20 h;在最适工艺条件下,胡麻籽油提取率可达86.73%。     

Functional properties of native and succinylated lentil (Lens culinaris) globulins

The functional properties of native and succinylated lentil globulins were evaluated. Succinylation caused a shift in the isoelectric pH of native globulins from 4.5 to 3.5 and improved the solubility above pH 4.0. However, below this pH the solubility of succinylated globulins was reduced. The water absorption and the viscosity of the sucinylated globulins were increased by almost 100%, while there was a decrease in the oil absorption capacity. The extent of succinylation used in this study did not show any significant relationships to these functional properties. Emulsion activity was also increased by succinylation; being 54.1% for the native globulins, 60% for the 57.9% succinylated globulins and 62.7% for the 87.2% succinylated globulins. Similarly, the emulsion stability was also improved. Foaming capacity of the succinylated globulins was decreased slightly, while foam stability, except at pH 2.5, was considerably reduced. Native and succinylated globulins showed maximum foam stabilities at pH 3.5 and 2.5, respectively.     

会宁胡麻油产地环境及产品特征

为提高会宁胡麻油品牌知名度和影响力,探究了地理标志产品会宁胡麻油的产地环境、种植方式及生产管理过程和品质特性。以会宁县17个乡镇的土壤和胡麻油为试验材料,采用国家相关标准对产地环境及胡麻油品质进行分析并采用气相色谱-质谱法对胡麻油风味物质进行分析。结果表明：会宁胡麻油的产地环境和产品安全指标均达到绿色食品标准;会宁胡麻油中α-亚麻酸平均含量为54.24%,不同产地间存在一定差异;会宁胡麻油含有65种风味物质,香味浓郁,其中己醛、正己醇、2-甲基吡嗪、γ-己内酯和3-甲基巴豆腈对会宁胡麻油独特的香味有重要影响。综上,会宁胡麻生长环境好,会宁胡麻油香味浓郁、营养价值高。