油脂品种对肉桂酸基油脂凝胶形成及性质的影响

菜籽油、玉米油和亚麻籽油为基料油添加肉桂酸,经加热搅拌、冷却静置后形成油脂凝胶。研究油脂品种对油脂凝胶临界成胶质量分数、持油性（oil binding capacity,OBC）、硬度、固体脂肪含量（solid fat content,SFC）、凝胶晶型及微观结构的影响。结果表明,油脂品种对油脂凝胶临界成胶质量分数无影响,临界成胶质量分数均为4%;对OBC有一定的影响,且随肉桂酸质量分数的增加油脂凝胶OBC明显增强;菜籽油油脂凝胶硬度最小,亚麻籽油油脂凝胶硬度最大;对SFC的影响为菜籽油油脂凝胶＜玉米油油脂凝胶＜亚麻籽油油脂凝胶。同时,晶型分析表明3?种油脂凝胶主要晶型均为β和β′。通过偏光显微镜观察出3?种油脂凝胶的晶体结构及晶体分布差异明显,说明油脂品种对油脂凝胶的微观结构有显著影响。     

甘蔗蜡制备稻米油基油凝胶及其相关性质

在稻米油中添加一定量的甘蔗蜡制成具有塑性的油脂凝胶。研究甘蔗蜡添加量对油脂凝胶硬度、热力学性质、固体脂肪含量（solid fat content,SFC）、X射线衍射（X-ray diffraction,XRD）和微观结构的影响。结果表明：在20 ℃条件下,油脂凝胶中甘蔗蜡添加量不小于7%时,即可出现凝胶行为。油脂凝胶体系的硬度、SFC、融化焓和结晶焓均随甘蔗蜡添加量的增多而增加。XRD结果显示,甘蔗蜡油脂凝胶中同时含有α、β、β’三种晶型,其中以β晶型为主,随着甘蔗蜡添加量增多,α和β’晶型的量增多。晶体呈球状,分布均匀。随甘蔗蜡添加量的增加,结晶数量增加,尺寸减小,导致分布密度增加,即甘蔗蜡添加量越高,硬度越大,结构化植物油的能力越强,形成油脂凝胶结构稳定性越好,表明在稻米油中加入甘蔗蜡可以形成油脂凝胶,该油脂凝胶中无反式脂肪酸,富含天然营养成分,具有适宜的油脂凝胶硬度及良好的结构稳定性等优势。     

蜡添加量对巴西棕榈蜡-油茶籽油凝胶物性、氧化稳定性及消化特性的影响

以油茶籽油为基料油,巴西棕榈蜡为凝胶剂制备巴西棕榈蜡-油茶籽油凝胶,探讨不同蜡添加量对其外观形态、持油率、硬度、晶型、热力学性质、氧化稳定性以及消化特性的影响。结果表明：蜡添加量为5%时才能使油茶籽油凝胶化,凝胶的硬度、持油率以及结晶/熔融峰值温度总体随着蜡添加量的增加而增大;凝胶的网络结构能够抑制油茶籽油次级氧化产物生成,提高油茶籽油的氧化稳定性;蜡添加量越高的凝胶脂肪酸释放率越低。     

小烛树蜡和日本木蜡对高油酸葵花籽油凝胶油结晶行为的差异比较北大核心CSCD

将小烛树蜡和日本木蜡分别添加到高油酸葵花籽油中制备凝胶油,分析其在凝胶油形成过程中结晶行为的差异。结果表明:在添加量为5%时,两种蜡均表现出低频率依赖的“强凝胶”行为,小烛树蜡具有更强的热稳定性和表观黏度,日本木蜡则具有更高的触变回复性;热力学性质进一步证实凝胶油性能的差异与天然蜡的成分有关。在微观层面上,小烛树蜡凝胶油和日本木蜡凝胶油分别呈现簇状和针状的晶体形态;小烛树蜡晶型为β′型,而日本木蜡则在形成凝胶油的过程中发生晶体排列堆积方式的改变,晶型由β′型转为β型。日本木蜡具有与高熔点蜡不同的特殊结晶性质,在塑性脂肪开发中具有潜在应用价值。     

玉米蜡含量对大豆油基凝胶油性质的影响

在大豆油中添加一定量的玉米蜡制成具有塑性的凝胶油。研究了玉米蜡含量对凝胶油结构及物理性质的影响。结果表明:玉米蜡含量对凝胶油的硬度、持油性、固体脂肪含量(SFC)、热学性质具有显著影响;随着玉米蜡含量增加,这些性质参数均有增大趋势;不同玉米蜡含量的凝胶油晶体均为细长针状,随玉米蜡含量增加,其针状结晶尺寸减小,空间分布密度增加;但玉米蜡含量对凝胶油体系的晶型影响不大。     

利用初榨大豆毛油制备β-谷甾醇油脂凝胶

利用初榨大豆毛油中天然磷脂,通过添加β-谷甾醇,使其与天然磷脂形成复合凝胶剂制备油脂凝胶,研究β-谷甾醇添加量对油脂凝胶硬度、热力学性质、固体脂肪含量（solid fat content,SFC）、凝胶晶型和微观结构的影响。结果表明：在20 ℃条件下,油脂凝胶中β-谷甾醇添加量不小于12%时,即可出现凝胶行为。油脂凝胶的硬度和SFC都随着β-谷甾醇添加量的增加而增加,且在不同贮藏温度下硬度变化显著。β-谷甾醇添加量对热力学特性影响较大,熔化结晶均为单峰。油脂凝胶主要为β型晶体,晶体为长针状并均匀分布,随β-谷甾醇添加量的增多,油脂凝胶晶体密度增大,尺寸变小,形成的三维网状结构更加紧密,截留植物油的能力不断提高,表明β-谷甾醇可以与初榨大豆毛油中的天然磷脂结合形成油脂凝胶,该油脂凝胶中无反式脂肪酸,富含天然营养成分,具有适宜油脂凝胶硬度及良好的结构稳定性等优势。     

急冷温度及凝胶剂添加量对植物甾醇/谷维素油凝胶物理特性的影响

为促进植物甾醇/谷维素油凝胶在零反式、低饱和的营养型塑性脂肪中的应用,以大豆油为基料油,植物甾醇/谷维素为凝胶剂,在不同急冷温度(5、20℃)及凝胶剂添加量下制备油凝胶,测定不同急冷温度及凝胶剂添加量下植物甾醇/谷维素油凝胶的晶型、晶体形态、物理稳定性、质构和热力学特性的变化。结果表明：随着凝胶剂添加量的升高,油凝胶中晶体排列逐渐致密,硬度增大,熔点升高;尽管急冷温度对油凝胶的晶型(β晶型)没有明显影响,但相对于5℃急冷,20℃急冷得到的油凝胶晶体组装更为致密,物理稳定性增强;在与传统甘三酯固脂对比SFC与硬度和熔点的关系中发现,在油凝胶体系中熔点随SFC的增加呈现非线性关系增长,但低固体脂肪含量(4.85%)即可赋予植物甾醇/谷维素油凝胶较高的硬度。综上,急冷温度及凝胶剂添加量对植物甾醇/谷维素油凝胶的物理特性具有显著的影响。     

大豆油基凝胶油储藏过程中结晶结构及物理性能变化研究

以大豆油为原料,添加玉米蜡制备玉米蜡基凝胶油,研究储藏温度及时间对凝胶油微观结构及物理性能的影响。结果表明,储藏不会改变凝胶油晶型,凝胶油形成的结晶呈长纤维针状,在20℃下12周的储藏中结晶的生长呈现生长-聚集-生长的趋势,而4℃下结晶的生长趋势为重组-生长-聚集-生长;4℃下凝胶油SFC变化不显著,凝胶油质量分数为1%、3%时硬度和持油性(OBC)随时间延长逐渐减小,而凝胶油质量分数为7%、10%、15%时硬度变化呈现先增后减,OBC储藏中变化不显著(P0.05);20℃下凝胶油SFC储藏6周后出现下降趋势,而硬度与OBC变化与4℃时储藏相似;4℃下凝胶油的SFC、硬度与持油性均要高于20℃,5%的凝胶油在4、20℃储藏中表现出不同的变化趋势。     

凝胶剂种类对凝胶油物性及结晶形态的影响研究*

以精炼低芥酸菜籽油为基料油,通过添加不同种类凝胶剂制备出两种模式凝胶油,并探讨了凝胶剂种类、搅拌等加工方式对凝胶油物化性质及结晶形态的影响,并使用低场脉冲核磁共振仪、质构仪、流变仪、差示量热扫描仪、粉末X-射线衍射仪、偏振光显微镜等手段对其固体脂肪含量、质构流变性质、熔化性质、晶型及晶体形态做了初步评价,为凝胶油在食品专用油脂中大规模应用奠定理论研究基础.     

米糠蜡添加量对亚麻籽油基油凝胶结构及性质的影响

为探究亚麻籽油基油凝胶作为替代传统塑性脂肪的潜力,以米糠蜡为凝胶剂,探究不同米糠蜡添加量对亚麻籽油基油凝胶外观形态、微观结构、持油率、理化性质及热力学性质的影响。结果表明：在室温条件下,米糠蜡添加量不小于6%时才会使亚麻籽油凝胶化;随着米糠蜡添加量的增加,油凝胶的结晶网络结构由簇状逐渐转变为针状,结晶密度增大;油凝胶的持油率、酸值以及熔融峰/结晶峰峰值温度均随着米糠蜡添加量的增加而增大;油凝胶的过氧化值随着米糠蜡添加量的增加呈现先增后减的趋势。综上,在亚麻籽油中添加适量的米糠蜡可形成热塑性好、结构稳定、理化性质良好、持油率高的油凝胶。     

Influence of wax type on characteristics of oleogels from camellia oil and medium chain triglycerides

Camellia oil (CO) and medium chain triglycerides (MCTs), characterised by different carbon chain lengths, were gelled using beeswax (BW), candelilla wax (CLW) and carnauba wax (CRW). Critical concentrations, oil-binding capacity (OBC), textural parameters, thermal properties, microscopic properties and infrared spectra were used to evaluate their differences. The carbon chain length of oil sources showed different results for the critical concentration of the three wax-based gel oils at 25 °C, and the oleogel of MCT and CLW exhibited a minimum value (1%). The oleogels formed from CO and waxes with wax esters as the main components (BW and CRW) exhibit significantly lower OBC and textural value than the oleogels made from MCT with BW and CRW. Meanwhile, this is corroborated with the thermal behaviour and crystal morphology, and distribution of the oleogels. However, no differences in crystal types and generation of new functional groups were observed by X-ray diffraction and Fourier-transform infrared spectrometer, suggesting that the differences in the properties of wax-based oleogels with different carbon chain lengths are attributed to the interactions between the waxes and the oil sources (physical interaction).     

Development of Formulations and Processes to Incorporate Wax Oleogels in Ice Cream

The objective of this study was to investigate the influence of emulsifiers, waxes, fat concentration, and processing conditions on the application of wax oleogel to replace solid fat content and create optimal fat structure in ice cream. Ice creams with 10% or 15% fat were formulated with rice bran wax (RBW), candelilla wax (CDW), or carnauba wax (CBW) oleogels, containing 10% wax and 90% high‐oleic sunflower oil. The ice creams were produced using batch or continuous freezing processes. Transmission electron microscopy (TEM) and cryo‐scanning electron microscopy were used to evaluate the microstructure of ice cream and the ultrastructure of oleogel droplets in ice cream mixes. Among the wax oleogels, RBW oleogel had the ability to form and sustain structure in 15% fat ice creams when glycerol monooleate (GMO) was used as the emulsifier. TEM images revealed that the high degree of fat structuring observed in GMO samples was associated with the RBW crystal morphology within the fat droplet, which was characterized by the growth of crystals at the outer edge of the droplet. Continuous freezing improved fat structuring compared to batch freezing. RBW oleogels established better structure compared to CDW or CBW oleogels. These results demonstrate that RBW oleogel has the potential to develop fat structure in ice cream in the presence of GMO and sufficiently high concentrations of oleogel.     

不同种类凝胶因子对芝麻油基凝胶油特性的影响

以芝麻油为原料,通过添加虫胶（Shellac,LAC）、单硬脂酸甘油酯（Monoacylglycerol,MAG）、乙基纤维素（Ethyl Cellulose,EC）三种不同种类凝胶因子制备出构型不同的凝胶油,并对凝胶油的持油能力、硬度、热力学性质、结晶形态等特性做了初步研究。结果表明,凝胶因子种类及添加比例对凝胶油临界成胶有一定影响,添加比例不小于5%时,LAC、MAG能形成凝胶,添加比例为3%时,EC能形成凝胶油;凝胶因子种类对持油性（Oil Binding Capacity,OBC）有重要影响,在凝胶因子添加比例为9%时,LAC凝胶油的OBC值最小,为55.3%;凝胶因子对硬度的影响中,三种不同凝胶油的硬度都随着凝胶因子添加比例增加而增大;在DSC曲线中,LAC凝胶油呈单峰、MAG凝胶油呈双峰、EC凝胶油峰度不明显;通过偏光显微镜观察,发现三种凝胶油的晶体形态结构及分散情况差别较大,LAC凝胶油晶体颗粒较小,呈细丫状;MAG凝胶油晶体颗粒偏大,先呈小球状后随添加量增大呈针状,表明凝胶油的微观结构受到凝胶因子种类的影响。     

Characterization of Hazelnut Oil Oleogels Prepared with Sunflower and Carnauba Waxes

In this study, hazelnut oil oleogels prepared with sunflower wax and carnauba wax were analyzed and compared with a commercial shortening. Oil binding capacities of sunflower wax oleogels were higher than 99%, while carnauba wax had a maximum value of 97.6% for 10% addition level. At 3% addition level of carnauba wax, no gel developed. The crystal formation time of sunflower wax was shorter. Although the highest (8.5%) solid fat content was observed in the 10% carnauba wax containing oleogel (HC10) sample, it was 30.4% in the commercial shortening sample at 20°C. The peak melting temperature of commercial shortening was 52.3°C, and among all organogels, sunflower wax oleogel at 3% addition level had the closest value (58.4°C). The melting enthalpies of the oleogels ranged from 4.3 to 20.3 J/g, while it was 10.9 J/g for the commercial shortening sample. The firmness and stickiness values in the oleogel samples were lower than that of commercial shortening sample. On the other hand, there was no significant change of firmness and stickiness during storage, indicating good stability (p ≤ 0.001). Especially the sunflower wax oleogels were very homogenous and smooth in structure. The polarized light microscopy pictures revealed needle-like crystals for sunflower wax and aggregate-like crystals for carnauba wax oleogels. The x-ray diffraction measurements of the crystals showed the β´ types of the polymorphic structures. Furthermore, the oleogels were very stable against oxidation during the storage period. Hazelnut oil organogels prepared with sunflower wax can be good source material for shortening or margarine-like products.     

植物蜡及液态植物油构建油凝胶的物性研究

以米糠蜡、棕榈蜡、蜂蜡3种食品级植物蜡为凝胶剂,葵花籽油、油茶籽油、亚麻籽油、棉籽油为基料油,构建了植物油基油凝胶,系统分析了油凝胶的外观形态、持油能力、微观结构、硬度、晶型及熔化结晶行为。结果发现,棕榈蜡基油凝胶涂抹性能优良,蜂蜡基油凝胶在三者中具有最高的持油能力。微观分析表明,米糠蜡形成的油凝胶晶体结构较为清晰,呈细长的针状;蜂蜡形成的油凝胶晶体结构最为细小,呈细小的针状;棕榈蜡形成的油凝胶,针型细密,并呈絮状结晶。晶体密度及样品硬度均随凝胶剂质量分数增加而增加。油凝胶的晶型与凝胶剂质量分数、基料油的种类无太大关系,主要取决于凝胶剂的种类。熔化结晶行为表明,凝胶剂种类相同时,随着其质量分数的增加,油凝胶的结晶/熔化峰值温度均升高。     

Physicochemical properties and oxidative stability of oleogels made of carnauba wax with canola oil or beeswax with grapeseed oil

Two types of oleogels—made of carnauba wax with canola oil or beeswax with grapeseed oil—were prepared at concentrations from 0 to 15% (w/w) of wax. Physical characterization was done and oxidative stability of the oleogels were evaluated. As the proportion of wax increased from 5 to 15%, the enthalpy of crystallization and melting increased in both oleogels. The carnauba wax-based oleogel (CWO) required greater enthalpy than the beeswax-based oleogel (BWO). Differences in L*, a*, and b* values between control oils and the oleogels significantly decreased as the concentration of wax increased in the oleogels (5–15%; p<0.05). Oil-binding capacity of the BWO was higher than that of the CWO. Solid-fat content of the CWO did not change significantly from 10 to 60oC, whereas that of the BWO decreased. In general, oxidative stability of the CWO was better at 60 and 180oC heat treatment in comparison with control oils (p<0.05). However, the BWO did not provide high oxidative stability than the control oils.     

葵花籽油基油凝胶在面包及冰淇淋产品中的应用研究

以葵花籽油为基料油,食品级植物蜡(米糠蜡、蜂蜡、棕榈蜡)作为凝胶剂构建油凝胶,分别以黄油、起酥油、葵花籽油作对照烘焙面包,以黄油、淡奶油作对照制备冰淇淋,对比分析不同油脂制作的面包和冰淇淋的感官及物性。结果表明:与对照组面包相比,油凝胶面包在各项指标上均无太大劣势,同时,油凝胶面包烘焙损失率比用传统黄油和起酥油烘焙面包小,且饱和脂肪酸含量降低;在抗融化性能方面,蜂蜡油凝胶冰淇淋和棕榈蜡油凝胶冰淇淋的抗融化性能好于黄油冰淇淋,但油凝胶冰淇淋膨胀率较低,不利于冰淇淋形成疏松绵软结构,且有少许蜡感,还需进一步改进。