重组毕赤酵母GS115-Ch-Glu发酵亚麻籽脱毒工艺的优化

以重组毕赤酵母GS115-Ch-Glu为对象,进行亚麻籽发酵脱毒工艺的研究,以HCN脱除率为主要指标考察了毕赤酵母发酵亚麻籽脱毒影响关键的几个因素,包括接种量、温度、p H、水分、发酵时间,并在此单因素试验基础上对亚麻籽发酵脱毒进行正交试验。确定最佳发酵脱毒工艺条件为:接种量1.5%、温度28℃、p H 6.5、水分含量55%及发酵时间48 h。在此最佳条件下,HCN脱除率达97.0%以上,是目前已知微生物法亚麻籽脱毒的最高HCN脱除率。     

亚麻籽粕不同脱毒方法的比较研究

采用挤压法、微波法、压热法、微生物法、水煮法、溶剂法等对亚麻籽粕进行处理,由比色滴定法测定亚麻籽粕中氢氰酸含量,比较分析不同处理方法对亚麻籽中生氰糖苷的脱除效果和机理。试验结果表明,挤压法与微波法最适合进行亚麻籽粕脱毒处理,氢氰酸(HCN)脱除率分别达到92.79%和89.64%,这十分有利于亚麻籽粕的开发应用。     

亚麻籽微波脱毒与挤压膨化脱毒工艺研究

采用微波法和挤压膨化法对亚麻籽进行脱毒.通过单因素试验,研究了微波法的烘烤时间、输出功率对脱毒效果的影响;通过二次正交旋转组合试验,研究了挤压膨化法的温度、水分、螺杆转速、喂料速度对脱毒效果的影响.微波脱毒法的研究结果表明,最佳烘烤时间为2 min,最佳输出功率为640 W;求得了挤压膨化法的回归数学模型并分析了单因素和交互作用对脱毒效果的影响.     

四种不同处理方法对于亚麻籽脱毒效果的研究

分别采用水煮法、烘烤法、微波法和蒸煮法对亚麻籽进行脱毒,通过实验确定了水煮法的最佳脱毒工艺参数为：水煮温度100℃,水煮时间20min,料水比1：20（W／Vh烘烤法的最佳脱毒工艺参数为：烘烤时间20min,烘烤温度120℃;微波法的最佳脱毒工艺参数为：微波输出功率640W,烘烤时间2min;蒸煮法的最佳脱毒工艺参数为：蒸煮时间25min,蒸煮温度120℃。通过比较得出水煮法最适合工业化大规模生产。     

亚麻籽脱毒的研究进展

亚麻籽是世界十大油料作物之一,有较高的利用价值,但因生氰糖苷的存在和毒性,限制了亚麻籽的使用和用量。本文详细介绍了亚麻籽生氰糖苷的组成、含量、致毒机理和脱毒方法等方面的国内外研究进展。     

亚麻籽生氰糖苷的研究进展

亚麻籽中毒性物质和抗营养因子(如抗维生素B6因子、生氰糖苷等)的存在,尤其是生氰糖苷的毒性限制了亚麻籽的使用。介绍了亚麻籽生氰糖苷的组成、结构特性及含量,并对其致毒机理、测定方法、脱毒方法以及潜在功能进行了详细的论述,以期为亚麻籽的综合开发及利用提供参考。     

亚麻籽中的生氰糖苷

概述了亚麻籽中生氰糖苷各组分的定性研究、含量分析及脱毒方法中效果较好的水煮法和混合溶剂浸出法的工艺条件和效果，对二糖苷的毒性作用机理、提取纯化方法及其开发应用方向—抗癌作用和在饲料中抗硒中毒作用也进行了探讨。     

西安油科院亚麻籽深加工项目通过成果鉴定

正[本刊讯]国家粮食储备局西安油脂科学研究设计院完成的"一步法亚麻木酚素提取及高蛋白亚麻籽粕脱毒与制备工艺"项目在西安通过了由陕西省科学技术厅组织的科技成果鉴定。据该课题组专家介绍,采用一步法用65%乙醇碱性溶剂提取亚麻籽饼粕中亚麻木酚素的同时脱除了生氰糖苷,提高了亚     

不同制油工艺对亚麻籽油品质及抗氧化活性的影响

为比较不同工艺制取的亚麻籽油品质及抗氧化活性,分别以索氏提取法、冷榨法和热榨法制取亚麻籽油,测定亚麻籽油得率、基本理化指标、生育酚含量、脂肪酸组成、挥发性成分及抗氧化活性。结果表明：索氏提取法亚麻籽油得率最高,为52.77%,热榨法亚麻籽油得率显著高于冷榨法;冷榨亚麻籽油色泽、脂肪酸组成较佳,α-亚麻酸含量高达54.49%;索氏提取亚麻籽油总生育酚含量最高,为450.79 mg/kg,冷榨和热榨亚麻籽油的总生育酚含量相当;索氏提取和冷、热榨亚麻籽油挥发性成分分别为21、17种和34种,5种为共有成分,其中(E,E)-2,4-庚二烯醛是冷、热榨亚麻籽油的特征风味物质;冷榨亚麻籽油具有较强的ABTS⁺自由基清除能力,而热榨亚麻籽油具有较强的DPPH自由基清除能力,二者铁还原力相当,索氏提取亚麻籽油具有较强的铁还原力。综上,不同制油工艺对亚麻籽油的品质及抗氧化活性具有一定的影响。     

两种方法提取的亚麻籽蛋白持水性、持油性、溶解性和氨基酸组成比较

以亚麻籽饼粕为原料,分别采用双酶复合法和碱溶酸沉法提取亚麻籽蛋白,测定并比较两种亚麻籽蛋白的持水性、持油性、溶解性及氨基酸组成。结果表明：碱溶酸沉法提取的亚麻籽蛋白的持水性在pH 6~7、40~80 ℃下优于双酶复合法;双酶复合法提取的亚麻籽蛋白的持油性在pH 4~8下优于碱溶酸沉法,但碱溶酸沉法提取的亚麻籽蛋白的持油性在40~100 ℃下优于双酶复合法;双酶复合法提取的亚麻籽蛋白的溶解性在pH 2~9（pH 3和pH 7除外）、20~60 ℃、NaCl浓度 0.3~15 mol/L下优于碱溶酸沉法;亚麻籽蛋白氨基酸种类丰富,谷氨酸含量最高,双酶复合法和碱溶酸沉法提取的亚麻籽蛋白的谷氨酸含量分别为10.793%和10.615%,两种方法氨基酸总和差异较小。     

Duplex real-time PCR method for the detection of sesame (Sesamum indicum) and flaxseed (Linum usitatissimum) DNA in processed food products

The development of a duplex real-time polymerase chain reaction (PCR) method allowing the simultaneous detection of sesame and flaxseed DNA in commercial food products is described. This duplex real-time PCR technique is based in the design of sesame- and flaxseed-specific primers based on the ITS1 region and two TaqMan fluorescent probes. The method was positive for sesame and flaxseed, and showed no cross-reactivity for all other heterologous plant and animal species tested. Sesame and flaxseed could be detected in a series of model samples with defined raw and heat-treated sesame in flaxseed, and flaxseed in sesame, respectively, with detection limits of 1.3 mg kg^?1 for sesame and 1.4 mg kg^?1 for flaxseed. The applicability of the assay for determining sesame and flaxseed in different food matrices was investigated by analysing a total of 238 commercial foodstuffs. This PCR method is useful for highly selective and sensitive detection of traces of sesame and flaxseed in commercial food products.     

基于SPME-GC-MS的青海亚麻籽油挥发性组分指纹图谱构建及掺伪识别

选用青海本地不同品种、产地的亚麻籽为原料,索氏抽提提取亚麻籽油,顶空固相微萃取（SPME）富集亚麻籽油挥发性组分后利用气相色谱-质谱联用技术（GC-MS）测定其种类及相对含量。分析40批样品的挥发性组分并构建纹图谱,利用指纹图谱识别鉴定掺入10%、20%、30%、40%、50% 6种不同植物油的亚麻籽油样品。结果表明,青海亚麻籽油样品中共含有58种挥发性组分,其中,醛类物质是亚麻籽油的主要风味物质;此外,6种不同植物油的指纹图谱与亚麻籽油标准指纹图谱相似度较小,该差异为亚麻籽油掺伪识别提供了可行性,在此基础上建立的掺伪模型适用于10%花生油、葵花籽油、芝麻油、20%以上玉米油、30%以上菜籽油、40%以上大豆油的掺假鉴定。该研究为亚麻籽油掺伪鉴别及品质控制提供了理论基础。     

亚麻籽仁饮料原浆制备条件筛选及优化

亚麻籽仁营养丰富,但其深度开发仍有较大空间。鉴此,试验以脱皮亚麻籽仁为原料,制备亚麻籽仁饮料原浆,以期为丰富亚麻籽产品种类提供科学依据。以亚麻籽仁蛋白提取率为指标,研究了打浆时间、料液比、打浆温度、浸泡时间和小苏打浸泡用量对亚麻籽仁饮料原浆的影响,利用Plackett-Burman及Box-Behnken设计筛选和优化亚麻籽仁饮料原浆制备工艺因素,获得亚麻籽仁饮料原浆最佳制备工艺条件:打浆温度60℃、打浆时间26 min、料液比1︰10 g/mL。制备的亚麻籽仁饮料原浆蛋白含量为1.53±0.07 g/100 mL,提取率为70.6%±0.35%。     

Effect of flaxseed physical form on digestibility of lactation diets fed to Holstein steers

Four multicannulated (rumen, duodenum, and ileum) Holstein steers (459.7 ± 46.4 kg of initial body weight) were used in a 4 × 4 Latin square design to determine the effect of flaxseed processing method on ruminal fermentation and digestibility. Treatments were based on inclusion of (1) 7.5% linseed meal (control), (2) 10% whole flaxseed, (3) 10% rolled flaxseed, or (4) 10% ground flaxseed on a dry matter (DM) basis, and were formulated to mimic typical high-producing dairy cow lactation diets. The control diet contained linseed meal in a proportion to provide crude protein (CP) equal to the amount of CP contributed by the flaxseed in the other treatments. Diets were fed for ad libitum intake and contained 30% corn silage, 17% chopped alfalfa hay, 6% sugar beet pulp, and 47% concentrate (comprising ground corn, supplemental protein, trace minerals and vitamins, and either flaxseed or linseed meal (DM basis). Diets were formulated to contain 17% CP, 34% neutral detergent fiber, 21% acid detergent fiber, and 4% fatty acid (DM basis). Periods were 14 d long and consisted of 7 d of adaptation and 7 d of sample collection. Dry matter intake (as a % of body weight) was similar (2.41 ± 0.17) for all treatments. The inclusion of flaxseed, regardless of processing method, tended to decrease total-tract organic matter digestibility relative to the linseed control, but no differences in CP intake, duodenal CP flow (bacterial, apparent feed, or total), ileal CP flow, fecal CP output, microbial efficiency, or CP digestibility (apparent ruminal, true ruminal, small intestine, large intestine, or total tract) were observed between treatments. Method of processing did not alter ruminal pH, ammonia, or volatile fatty acids production. The ground flaxseed treatment had the fastest rate of in situ DM degradation (11.25%/h), followed by the control (7.46%/h), rolled flaxseed (4.53%/h), and whole flaxseed (0.57%/h) treatments. Degradability of CP and fat followed the same pattern as DM degradability for processed flaxseed. In situ degradation rates of alfalfa hay neutral detergent fiber and acid detergent fiber tended to be fastest for the ground flaxseed treatment. Taken together, the digestibility, fermentation, and in situ data indicate that rolling and grinding are both acceptable methods of processing flaxseed. The in situ data strongly support the need for processing flaxseed before inclusion in lactation diets.     

Chromatographic separation of flaxseed phenolics

A column chromatography method for separation of phenolic compounds from flaxseed using Sephadex LH-20, RP-8 and silica gel is described. TLC analysis proved that separated fractions contained numerous phenolic compounds. All fractions exhibited a maximum UV absorption between 270 and 290 nm. Additional shoulders were observed between 274 and 350 nm. These results imply that lignans and their derivatives are the main phenolic compounds present in flaxseed.     

不同制油方法对青海亚麻籽油品质及货架期的影响

为研究不同制油方法对青海亚麻籽油品质及货架期的影响,对青海亚麻籽分别进行焙炒、烘烤、高压高温湿热、脱胶、真空冷冻干燥前处理,再分别采用螺旋压榨法和液态静压法制油,测定亚麻籽油出油率、过氧化值、酸价、水分及挥发物质量分数、脂肪酸含量、挥发性组分相对含量、总酚含量,并利用Schaal烘箱法建立亚麻籽油氧化动力学模型预测货架期。结果表明,焙炒螺旋压榨法制得的亚麻籽油出油率、总酚含量明显高于其他处理组,过氧化值、酸价、水分及挥发物质量分数均低于其他处理组,模拟预测货架期最长,为353 d。焙炒螺旋压榨法制得的亚麻籽油挥发性组分种类最多,为72 种,其他制油方法制得的亚麻籽油挥发性组分为40～60 种,不同制油方法对亚麻籽油挥发性组分影响明显。此外,亚麻籽油5 种主要脂肪酸中亚麻酸含量最高,为54.71～61.03 g/100 g,不同制油方法对亚麻籽油脂肪酸含量影响不明显。综上,与其他方法相比,焙炒螺旋压榨法制得的亚麻籽油品质较好。     

不同亚麻籽品种氨基酸含量测定及品质综合评价

目的：研究不同亚麻籽品种氨基酸含量及基于氨基酸含量的品质差异。方法：以6个产地的12个亚麻籽品种为研究对象,测定其氨基酸含量,并以17种氨基酸含量为评价指标进行主成分分析和聚类分析,研究不同品种亚麻籽氨基酸含量及基于氨基酸含量的品质差异。结果：亚麻籽品种对不同氨基酸含量的影响顺序为Met>Cys>Phe>Tyr>Arg>Glu>Pro>His>Asp>Ser>Lys>Gly>Thr>Ala>Ile>Val>Leu。主成分分析提取出3个主成分,其累计方差贡献率达86.695%,Ala、Arg、Thr、Leu和Cys可以作为12个亚麻籽品种基于氨基酸含量的品质综合评价指标。隶属函数法评价得出12个亚麻籽品种基于氨基酸含量的品质优劣顺序为晋亚7>晋亚8>轮选2>坝亚9>伊亚3>轮选1>宁亚16>宁亚17>伊亚4>陇亚8>坝亚11>陇亚10。结论：综合品质最佳亚麻籽品种为晋亚7,最差亚麻籽品种为陇亚10,综合评价将12个亚麻籽品种划分为四大类。     

An efficient fermentation method for the degradation of cyanogenic glycosides in flaxseed

Recently, flaxseed has become increasingly popular in the health food market because it contains a considerable amount of specific beneficial nutrients such as lignans and omega-3 fatty acids. However, the presence of cyanogenic glycosides (CGs) in flaxseed severely limits the exploitation of its health benefits and nutritive value. We, therefore, developed an effective fermentation method, optimised by response surface methodology (RSM), for degrading CGs with an enzymatic preparation that includes 12.5% β-glucosidase and 8.9% cyanide hydratase. These optimised conditions resulted in a maximum CG degradation level of 99.3%, reducing the concentration of cyanide in the flaxseed power from 1.156 to 0.015?mg?g^?1 after 48?h of fermentation. The avoidance of steam heat to evaporate hydrocyanic acid (HCN) results in lower energy consumption and no environmental pollution. In addition, the detoxified flaxseed retained the beneficial nutrients, lignans and fatty acids at the same level as untreated flaxseed, and this method could provide a new means of removing CGs from other edible plants, such as cassava, almond and sorghum by simultaneously expressing cyanide hydratase and β-glucosidase.     

亚麻籽营养成分提取及其功能和应用研究进展

综述了亚麻籽中亚麻籽油、亚麻籽蛋白、亚麻籽多糖、亚麻籽胶、木脂素等主要营养成分的提取方法及其原理和优缺点,并对其调节脂质代谢、降低血糖血脂水平、改善心脑血管疾病、预防癌症等营养功能及在食品加工等领域的应用进行分析和讨论,以期为亚麻籽营养成分的提取和相关产品的进一步开发利用提供参考。