Increase of viability of entrapped cells of Lactobacillus delbrueckii ssp. bulgaricus in artificial sesame oil emulsions

A technique was developed to protect lactic acid bacteria (Lactobacillus delbrueckii ssp. bulgaricus) against simulated gastrointestinal conditions by encapsulation of bacterial cells within artificial sesame oil emulsions. Purified sesame oil bodies consisting of approximately 99% oil, 0.5% phospholipid, and 0.5% protein were decomposed by heating at 70 degrees C for 1 h. The bacteria cultured in nonfat milk were encapsulated in artificial oil emulsions constituted with decomposed sesame oil bodies and excess sesame or vegetable cooking oil. Viability of bacteria in storage at 4 degrees C for 16 d was substantially elevated from 0.023 to 5.45% after encapsulation. Compared with free cells, the entrapped bacteria demonstrated a significant increase (approximately 10(4) times) in survival rate when subjected to simulated high acid gastric or bile salt conditions. The results indicate that artificial sesame oil emulsion may serve as an effective biocapsule for encapsulation of bacteria in dairy products.     

Effects of Roasting Conditions on the Changes of Stable Carbon Isotope Ratios (δ13C) in Sesame Oil and Usefulness of δ13C to Differentiate Blended Sesame Oil from Corn Oil

Abstract: Differentiating blended sesame oils from authentic sesame oil (SO) is a critical step in protecting consumer rights. Stable carbon isotope ratios (δ¹³C), color, fluorescence intensity, and fatty acid profiles were analyzed in SO prepared from sesame seeds with different roasting conditions and in corn oil blended with SO. Sesame seeds were roasted at 175, 200, 225, or 250 °C for 15 or 30 min at each temperature. SO was mixed with corn oil at varying ratios. Roasting conditions ranging from175 to 250 °C at the 30 min time point did not result in significant changes in δ¹³C (P > 0.05). Values of δ¹³C in corn oil and SO from sesame seeds roasted at 250 °C for 15 min were −17.55 and −32.13 ‰, respectively. Fatty acid ratios, including (O + L)/(P × Ln) and (L × L)/O, where O, L, P, and Ln were oleic, linoleic, palmitic, and linolenic acids, respectively, showed good discriminating abilities among the SO blended with corn oil. Therefore, using different combinations of stable carbon isotope ratios and some fatty acid ratios can allow successful differentiation of authentic SO from SO blended with corn oil. Practical Application: Adulteration of sesame oil with less expensive oils such as corn oil or soybean oil to reduce cost is a common unethical practice in Korea. Due to the unique and strong flavor of sesame oils that may mask other weaker flavors, however, differentiating authentic sesame oils from blended oils is difficult. This study showed that the roasting process did not significantly affect the ratios of the stable carbon isotope (δ¹³C) in sesame oils. δ¹³C was confirmed to be a reliable parameter. Moreover, some fatty acid ratios were designed to discriminate between blended sesame oil with corn oil and authentic sesame oil.     

Effect of Infrared Heating on the Formation of Sesamol and Quality of Defatted Flours from Sesamum indicum L.

ABSTRACT:  Infrared (IR) heating offers several advantages over conventional heating in terms of heat transfer efficiency, compactness of equipment, and quality of the products. Roasting of sesame seeds degrades the lignan sesamolin to sesamol, which increases the oxidative stability of sesame oil synergistically with tocopherols. IR (near infrared, 1.1 to 1.3 μm, 6 kW power) roasting conditions were optimized for the conversion of sesamolin to sesamol. The resultant oil was evaluated for sesamol and tocopherol content as well as oxidative stability. The defatted flours were evaluated for their nutritional content and functionality. IR roasting of sesame seeds at 200 °C for 30 min increased the efficiency of conversion of sesamolin to sesamol (51% to 82%) compared to conventional heating. The γ-tocopherol content decreased by 17% and 25% in oils treated at 200 and 220 °C for 30 min, respectively. There were no significant differences in the tocopherol content and oxidative stability of the oil. Methionine and cysteine content of the flours remained unchanged due to roasting. The functional properties of defatted flours obtained from either IR roasted or conventionally roasted sesame seeds remained the same.
Practical Applications: Sesame oil is stable to oxidation compared to other vegetable oils. This stability can be attributed to the presence of tocopherols and the formation of sesamol, the thermal degradation product of sesamolin—a lignan present in sesame. Roasting of sesame seeds before oil extraction increases sesamol content which is a more potent antioxidant than the parent molecule. The conversion efficiency of sesamolin to sesamol is increased by 31% by infrared roasting of seeds compared to electric drum roasting. This can be used industrially to obtain roasted oil with greater oxidative stability.     

芝麻油中掺加大豆油鉴别方法的研究

利用气相色谱法分析和确定香油中脂肪酸组成的分布特征,以此建立一种快速鉴别香油是否掺加大豆油的分析方法。研究结果表明,测量假芝麻油样品中C18∶1n9c和C18∶3n3两种特征脂肪酸含量,使用二元一次方程可以计算假芝麻油中大豆油的含量,芝麻油约为90%时,最大计算误差为8.16%,其结果为(实测值±7.36) g/100 g;芝麻油约为70%时,最大计算误差为15.55%,其结果为(实测值±10.84) g/100 g;芝麻油约为50%时,最大计算误差为30.35%,其结果为(实测值±15.00) g/100 g。这个计算方法是可行的,可以用来鉴别芝麻油中是否掺加大豆油,并计算出掺假芝麻油中大豆油的含量。     

电子鼻在芝麻油及芝麻油香精识别中的应用

采用电子鼻时芝麻油、芝麻油香精和其他油脂样品进行了分析.对所获得的数据进行主成分分析(Principal Component Analysis,PCA)、判别因子分析(Discriminant Factor Analysis,DFA)和统计质量控制分析(Statistical Quality Control,SQC),结果表明:电子鼻能够有效识别芝麻油、芝麻油香精和其他油脂,且电子鼻对芝麻油和其他油脂的识别比对芝麻油和芝麻油香精的识别效果更好;2号芝麻油香精和芝麻油样品的香气较为相似,其香气的模拟比较成功;电子鼻能够识别不同储存时间的芝麻油样品,随着储存时间的延长,样品在PCA图中呈现规律性的变化,这可能与芝麻油在储存过程中发生氧化有关.     

Employing an intelligence model and sensitivity analysis to investigate some physicochemical properties of coated bell pepper during storage

The objectives of this work were to study the effects of three different coatings (gum Tragacanth, sesame oil and gum Tragacanth–sesame oil), temperature and time on shelf life of bell pepper. Moisture reduction, shrinkage as well as firmness and colour changes were studied during 30 days at 4, 10, 15 and 23 °C. Results of this study showed that bell peppers treated with gum Tragacanth at higher temperatures, such as 10 °C, had good quality up to 30 days of storage. However, sharp changes in physicochemical characters were observed in bell peppers stored at 23 °C. In order to predict moisture reduction, shrinkage, firmness and colour changes genetic algorithm–artificial neural network model was developed. It was found that artificial neural network with eight hidden neurons truly could predict the physicochemical changes of bell pepper during storage (R² > 0.9598). The results of sensitivity analysis showed that shrinkage percentage and also changes of firmness and colour were very sensitive to storage time, while storage temperature had the most effect on moisture reduction.     

拉曼光谱-聚类分析快速鉴别掺伪芝麻油

目的建立快速鉴别掺伪芝麻油的拉曼光谱-聚类分析方法。方法以不同产地、不同品牌的多批次芝麻油、大豆油、玉米油、菜籽油、精炼棕榈油、精炼棉籽油及精炼地沟油为样品,在780 nm和532 nm激光光源下,扫描和比较其普通、扩展及导数拉曼光谱的形态。结果在532 nm激光光源的扩展光谱及一阶导数光谱中,芝麻油与低价植物油及精炼地沟油光谱的信息量最大,样品间光谱形态的差异显著。基于此全波段光谱信息和形态建立的多步聚类分析模型对芝麻油、低价植物油、仿冒芝麻油和精炼地沟油的判别正确率均为100%;对5%、10%、20%、30%和50%掺假芝麻油的判别正确率分别为72%、92%、100%、100%和100%;对5%、10%和20%掺杂芝麻油的判别正确率分别为97%、100%和100%;对5%、10%和20%掺杂植物油的判别正确率分别为94%、100%和100%。样品测量时无需制备样品及消耗化学试剂,测量和分析一份样品仅耗时5 min左右。结论所建立的拉曼光谱-聚类分析模型既可准确鉴定芝麻油,还可准确鉴定各种类型的掺伪芝麻油,可实现对掺伪芝麻油的快速、无损和准确鉴别。     

芝麻适度压榨工艺条件研究

在传统的芝麻油和芝麻酱生产工艺的基础上,引入适度压榨工艺,采用适当的压榨条件提取部分芝麻油,同时保证芝麻饼的加工性能用于低脂芝麻酱的磨制。文章以压榨后的芝麻饼的松散程度和出油率为指标,通过单因素试验和正交试验对压榨压力、压榨次数、榨膛温度和入料温度进行选择与优化。确定的最佳压榨条件为:压榨压力30 MPa、压榨次数2次、入料温度25~35 ℃,在此条件下对焙炒后的芝麻进行适度压榨,出油率为17.3%,得到的芝麻饼松散程度评分为7.7,加工性能良好。以此芝麻饼为原料磨制的低脂芝麻酱相比同批原料制作的传统芝麻酱脂肪含量降低了10.0%,蛋白质含量增加了3.8%。应用该工艺得到的芝麻油色泽金黄、香味较淡,可用作烹饪油。     

Optimization of Sesame Oil Extraction by Screw-Pressing at Low Temperature

Box-Behnken designs were used to optimize a process for sesame oil extraction by screw-pressing at low temperature (50 °C). Experimental designs included seed moisture content (SMC), pressing speed (PS), and restriction die (RD) as the main processing parameters. Extractions at pilot plant scale showed a peak in oil recovery (OR, 71.1 ± 2.80%) at 12.3% SMC, 4 mm RD, and 20 rpm PS. Theoretical models were scanned against experimental data in order to scale up the proposed oil extraction process to industrial scale. A fitted model for OR showed a maximum predicted value similar to the highest experimental value (74.4 ± 1.23%) under the following conditions: 8.03% SMC, 10 mm RD, and 20 rpm PS. Chemical quality parameters of oils obtained at both pilot and industrial scales were in the ranges stated in Codex (FAO/WHO) standards for non-refined sesame oil.     

Oxidative Stability of ω3-rich Camelina Oil and Camelina Oil-based Spread Compared with Plant and Fish Oils and Sunflower Spread

ABSTRACT: The oxidative stability of ω3‐rich oil from Camelina sativa and the storage stability of a camelina oil‐based spread were evaluated. Camelina oil was more stable than fish oil and linseed oil, but less stable than sunflower, corn, sesame, and olive oils, indicated by measuring peroxide values (PV), ρ‐anisidine values (AV), total oxidation values (Totox), thiobarbituric acid reactive substances (TBARS), conjugated diene levels (CD), and conjugated triene levels (CT) during storage at 65 °C for 16 d. The camelina oil‐based spread had higher PV, AV, Totox, TBARS, CD, and CT than the sunflower spread but maintained adequate sensory quality for 16 wk of storage at 4 °C or 8 °C.     

石斛粉葛咀嚼片的制备及其抗氧化活性

以石斛和粉葛为原料,经超微粉碎、配料、湿法造粒、干燥、整粒、压片等工序制成咀嚼片。考察了原料比、辅料比、乙醇浓度、60%乙醇添加量、硬脂酸镁添加量对咀嚼片感官品质的影响,在单因素实验基础上,采用L₁₆(45)正交试验优化咀嚼片配方;以DPPH·清除能力、ABTS+·清除能力、总抗氧化能力为模型评价咀嚼片抗氧化活性。结果表明,石斛粉葛咀嚼片最佳工艺配方为:原料中石斛:粉葛为1:4,原辅料比[(石斛+粉葛):辅料(玉米淀粉+菊粉+木糖醇+甘露醇)]为1:1.5,辅料配比(玉米淀粉:菊粉:木糖醇:甘露醇)为4:3:1:1,润湿剂60%乙醇的添加量为0.4 mL/g,硬脂酸镁1.5%,咀嚼片感官评分为93.7±0.03分。石斛粉葛咀嚼片水提液、石斛粉葛咀嚼片醇提液与抗坏血酸(V_C)的清除DPPH·的IC₅₀值分别为(3.067±0.1095)、(3.512±0.0945)、(0.06337±0.0286) mg/mL;石斛粉葛咀嚼片水提液、石斛粉葛咀嚼片醇提液与V_C的清除ABTS+·的IC₅₀值分别为(5.529±0.8175)、(5.380±0.7915)、(0.2772±0.0345) mg/mL;石斛粉葛咀嚼片水提液、醇提液、V_C在浓度为2 mg/mL时,总抗氧化能力分别为0.258、0.188、0.494。石斛粉葛咀嚼片有一定的抗氧化活性,石斛与粉葛有协同抗氧化作用。     

加工工艺对芝麻酱稳定性的影响

为探明影响芝麻酱贮藏稳定性的关键工艺和核心指标,比较了炒制工艺（焙炒温度、时间）、不同原料处理方式（脱皮与未脱皮）、磨酱次数等关键工艺条件,测定其离心析油率、沉降析油率等贮藏稳定性指标以及粒径、比表面积等物化特性,通对不同工艺条件下各指标的变化进行分析归纳以及相关性分析,阐明加工工艺与贮藏稳定性之间的相关性。结果表明:芝麻的焙炒时间对酱体沉降析油率影响显著,焙炒时间延长析油率呈现先下降趋势,后趋于平稳,焙炒温度对芝麻酱沉降析油率影响不显著,但是温度不宜超过230 ℃,否则产品有焦糊味,研究发现芝麻酱离心析油率与30、60、90 d的沉降析油率的相关系数分别为0.966、0.955、0.967,呈现极显著正相关,离心析油率与芝麻酱的中位径D50、平均粒径Dav值也为显著正相关,相关系数为0.952和0.913,但是与比表面积S/V呈现负相关,相关系数为?0.930。另外,对比了脱皮芝麻和未脱皮芝麻加工成芝麻酱的离心析油率和黏度,发现芝麻皮的存在可以提高酱体黏度而有利于稳定贮藏,降低离心析油率,综合来看,在焙炒温度220 ℃,焙炒时间20 min,磨酱次数3次,离心析油率为3.34%,该条件下加工的芝麻酱的离心析油率最低,稳定性最佳。     

Effects of Sesame Oil Addition to Soybean Oil During Frying on the Lipid Oxidative Stability and Antioxidants Contents of the Fried Products During Storage in the Dark

ABSTRACT: Effects of sesame oil addition to soybean oil during frying on the lipid oxidative stability and antioxidants contents of fried products during storage in the dark were studied. Flour dough pieces (2 cm × 2 cm × 0.1 cm) were fried at 160 °C for 1 min in sesame oil-added soybean oil. Concentrations of sesame oil in the frying oil were 0%, 10%, and 20% by volume. Fried products were put into a glass bottle, and the bottles were tightly sealed and stored at 60 °C in the dark for 18 d. Lipid oxidation of fried products was determined by fatty acid composition changes and conjugated dienoic acid (CDA) and p -anisidine (PA) values. Tocopherols and lignan compounds in the fried products were determined by high-performance liquid chromatography. Relative content of linolenic acid decreased, and CDA and PA values increased during storage of the fried products in the dark. Fatty acid composition change and CDA and PA values during storage were lower in the products fried in sesame oil-added soybean oil than in the products fried in soybean oil without sesame oil. The results clearly showed that addition of roasted sesame oil to soybean oil at 10% and 20% during frying decreased the lipid oxidation of fried products during storage in the dark for 18 d by extension of induction period and decrease in decomposition of oxidized lipids. Fried products contained 134 to 267 ppm tocopherols and 0 to 148 ppm lignans before storage; however, their contents decreased during storage in the dark. Lignan compounds were more stable than tocopherols, and the rate of tocopherols degradation was lower in the products fried in sesame oil-added soybean oil than in the products fried in soybean oil without sesame oil, which could be because of protection of tocopherols from degradation by lignan compounds.     

巴氏灭菌对不同油脂体乳液氧化稳定性的影响

为探究巴氏灭菌对大豆、葵花、花生、芝麻和核桃油脂体乳液氧化稳定性的影响,本研究测定不同油脂体的基本组成、相关蛋白组成、脂肪酸组成和相对含量,然后利用动态光散射、激光共聚焦显微镜等研究巴氏灭菌（85 ℃加热10 min）对油脂体乳液物理稳定性和氧化稳定性的影响。结果表明：不同油脂体的基本组成、相关蛋白组成和脂肪酸组成存在明显差异,油脂体相关蛋白由内源膜蛋白和外源蛋白组成,油脂体脂肪酸以不饱和脂肪酸为主,其中油酸、亚油酸和α-亚麻酸是主要的不饱和脂肪酸。5 种不同原料油脂体中,大豆油脂体蛋白质量分数和水分质量分数最高,而油脂质量分数最低;花生油脂体总饱和脂肪酸相对含量（21.27%）最高,核桃油脂体总不饱和脂肪酸相对含量（90.10%）最高。巴氏灭菌可显著改善大豆和花生油脂体乳液氧化稳定性,而对葵花、芝麻和核桃油脂体乳液起促进氧化作用。本研究可为油脂体在沙拉酱、植物奶等产品应用提供参考。     

芝麻香油粉末油脂风味物质研究

为考察芝麻香油粉末油脂制备方法对风味物质的影响,采用固相微萃取结合气相色谱-质谱联用技术对芝麻香油及其冷冻干燥法和喷雾干燥法制备的粉末油脂中风味物质进行了分析。结果表明:粉末油脂制备过程的加热对芝麻香油风味产生了较大的影响,既造成了风味物质的挥发、损失,又衍生出新的物质;冷冻干燥法制备的粉末油脂风味物质稍有变化;喷雾干燥法制备的粉末油脂除醛类相对稳定外,烃类产生新的衍生物,醇类、酯类、酚类明显减少,吡嗪类未检出,酸类物质显著增加。可见,冷冻干燥法制备粉末油脂更适用于风味要求高、易挥发的芝麻香油产品。     

香油精电子鼻快速检测系统的设计

为实现香油精的快速检测,研制了一套能够实时、准确地进行香油精检测的系统。该系统主要由数据采集部分和数据处理部分组成。数据采集部分采用了气体传感器阵列和上位机结合的方式,数据处理部分用Matlab训练了一个3层BP神经网络。在实验过程中,配制了8个不同比例的香油精样本,用标准样本进行了神经网络的训练,测试样本进行了验证。该系统为香油精的快速检测方法的研究提供了依据,据有一定的实用价值。     

APPLICATION OF SEMIPREPARATIVE RP-18 HPLC FOR THE PURIFICATION OF SESAMIN AND SESAMOLIN

A relatively simple chromatographic protocol was established to provide good separation of the unsaponifiable constituents from the seed oil of Sesamum indicum Linn. The protocol employs classical column chromatography using alumina and petroleum ether to collect furofuran lignans from sesame oil. Semipreparative RP-18 HPLC was used to separate the sesamin and sesamolin constituents in high purity (> 99%). The purity and identity of the separated compounds was confirmed by rechromatography using an analytical HPLC set up and GC-MS, respectively. The method described offers a means to isolate and collect sesamin and sesamolin in high purity for use as standards in furofuran lignan studies of sesame seed oil.     

微波预处理对芝麻油中芝麻木酚素含量及油脂品质的影响

为了确定高芝麻酚芝麻油的最适微波预处理条件,将芝麻水分含量调节为5个梯度,在不同微波预处理时间下制得芝麻油样品,对其芝麻木酚素含量、酸值、茴香胺值、氧化诱导时间、脂肪酸组成、生育酚含量、有害物质（多环芳烃和杂环胺）含量及感官品质进行了分析,探究芝麻水分含量和微波预处理时间对芝麻油中芝麻木酚素含量及油脂品质的影响。结果表明：微波预处理时间6 min、芝麻水分含量7%条件下制得的芝麻油芝麻酚含量较高,芝麻油酸值符合国家标准限定要求,氧化稳定性较强,有害物质杂环胺和多环芳烃含量处于适当的可控水平,同时兼顾了芝麻油的固有风味,消费者的喜爱度较高。综上,高芝麻酚芝麻油的最适微波预处理条件为微波预处理时间6 min,芝麻水分含量7%。     

低温压榨芝麻油的工艺研究

通过单因素和正交试验分析,确定了低温压榨芝麻油的最佳工艺条件为芝麻粉碎粒度20 目、压榨温度50℃、时间60min、压力40MPa。在此条件下芝麻油提取率43.46%。此工艺条件下生产的芝麻油样品含有丰富的抗氧化成分,不含苯并芘,理化指标和氧化稳定性好于普通芝麻油。     

CHEMICAL CHANGES IN STORED TOASTED CRUDE CANOLA AND SESAME SEED OILS

'Alto'canola seed and sesame seed were toasted at 180, 200, 220, 240, and 260C, for 8 min or 10 min. As temperature increased, minor changes in fatty acid composition were observed. Darkness and blueness in canola oil increased with toasting temperatures up to 240C, and then decreased. The darkness, greenness and yellowness of sesame seed oil increased with increasing toasting temperature. The overall color of canola oil was significantly darker than that of sesame seed oil (α 0.05). 2-Thiobarbituric acid (TBA) numbers for both oils increased as toasting temperature increased. TBA numbers of the canola oil increased with extended storage time up to 4 weeks and then decreased. For sesame seed oil, TBA numbers also were influenced by storage time, but less change was observed than for canola oil. 2-Thiobarbituric acid reactive substances (TBARS) content of canola oil was significantly higher than that for sesame seed oil when TBA numbers were compared to the same treatment.