亚麻胶的应用研究

本文对亚麻胶的增粘性、起泡性能、乳化性能等进行研究并与其他胶进行了比较。利用其优越的起泡性能和乳化性能 ,亚麻胶在果汁饮料、蛋白饮料和冰淇淋等食品中具有较好的稳定性和乳化作用     

3种植物胶物化性能的对比研究

利用天然植物资源通过纯化分离得到了亚麻胶和沙枣胶。对3种植物胶阿拉伯胶、沙枣胶和亚麻胶的理化指标、增稠性、协同增稠性、乳化和泡沫性能进行了对比研究,结果表明,沙枣胶和亚麻胶可以取代商品阿拉伯胶。     

亚麻胶、亚麻木酚素的提取及分离纯化技术研究进展

本文对国内外亚麻籽中亚麻胶、亚麻木酚素提取和分离纯化技术进行综述,为进一步完善其提取和分离提纯工艺,以实现亚麻胶、亚麻木酚素、亚麻籽油及蛋白的高效提取与综合利用.     

响应面法优化富锌酵母培养条件

该研究利用双酶复合酶解法和碱溶酸沉法从亚麻籽饼粕中提取亚麻蛋白,探究两种提取方法及不同因素对亚麻蛋白功能性质的影响。结果表明,双酶复合酶解法提取的亚麻蛋白功能性质较碱溶酸沉法更优,且不同因素对亚麻蛋白功能性质具有一定的影响。双酶复合酶解法提取的亚麻蛋白的等电点为4.4,且当pH值11、温度60 ℃、亚麻蛋白含量3.4%和NaCl浓度1.5 mol/L时,乳化性最佳;当pH值11、温度40 ℃、亚麻蛋白含量3.4%和NaCl浓度1.5 mol/L,乳化稳定性最佳;当pH值11、温度60 ℃、亚麻蛋白含量2.8%和NaCl浓度1.0 mol/L时,起泡性最佳;当pH值8、温度60 ℃、亚麻蛋白含量3.4%和NaCl浓度1.0 mol/L时,起泡稳定性最佳;当pH值2、温度20 ℃、亚麻蛋白含量2.2%和NaCl浓度1.0 mol/L时,黏度最佳。     

亚麻籽的营养成分及功能研究进展

亚麻籽是世界十大油料作物之一,营养价值较高。亚麻籽含有α-亚麻酸、亚麻籽蛋白、亚麻木酚素、膳食纤维和亚麻胶等多种营养成分,从而使亚麻籽具有降血糖、降血脂和预防心脑血管疾病等多种功能。对亚麻籽的营养成分及其功能研究进展进行综述,以期为促进亚麻产业发展提供参考。     

一种新型的食品添加剂--亚麻胶

亚麻胶 [法定编号 :ＧＢ12 4 93— 90 (2 0 .0 2 0 ) ]是从油料作物亚麻籽 (又名胡麻籽 )中提取的一种新型食用胶。它是以多糖类物质和蛋白质为主要成分的天然高分子复合胶。1　亚麻胶的特性1 1　外观特征亚麻胶为粉状 ,呈淡黄色 ,带有亚麻籽原色。1 2　溶解性亚麻胶直接撒于水中 ,易吸水结团 ,如与糖、盐、蛋白、淀粉等物料混合后容易分散于水中 ,且在 75℃的水中加热 10分钟 ,可充分溶解 ,释放胶性。在具体应用中 ,亚麻胶随肉料的加热过程 ,即完成溶解过程 ,显示出各种性能。1 3　亚麻胶溶液特性热溶打开后的亚麻胶溶液为淡黄色 (允许有少…     

亚麻壳中亚麻胶提取工艺优化研究

研究了亚麻壳中亚麻胶的提取工艺,针对提取温度、时间、水料比及洗胶次数4个因素时行了单因素实验及正交实验,实验结果表明:温度对亚麻胶提取的影响最大,其次是水料比,结合工艺过程和实验结果,选定亚麻壳中亚麻胶的最佳提取工艺条件为:温度80℃,时间40 min,水料比15 m L/g,洗胶次数2次。在此条件下亚麻胶的提取率是13.4 g/100 g。     

魔芋胶与大豆分离蛋白相互作用研究

以魔芋胶与大豆分离蛋白为试材，研究两者之间的复合增稠性、乳化性及胶凝性，并对两者之间的作用机理进行了探讨。结果发现魔芋胶与大豆分离蛋白复配具有明显的协同增稠作用；魔芋胶对低浓度大豆分离蛋白的乳化性能具有显著的改善作用；魔芋胶与大豆分离蛋白复配具有较好的胶凝作用。显微结构观察表明魔芋胶与大豆分离蛋白复配后两者胶束间发生一定的相互作用；红外光谱分析表明复配后两者分子上的化学基团没有发生本质上的改变，但氢键作用增强；复配凝胶体系中作用力的研究结果表明体系中作用力主要为氢键作用，从而说明魔芋胶与大豆分离蛋白主要是通过分子间氢键发生作用。     

硫酸酯化亚麻胶的制备与分析

采用氯磺酸-吡啶法,通过单因素和正交实验得出制备硫酸酯化亚麻胶的最佳工艺条件为:吡啶-氯磺酸比值为2,反应温度60℃,反应时间4h,此工艺奈件下产物取代度为1.34 红外光谱分析表明,该条件下其部分羟基已被硫酸基取代;酯化后的亚麻胶黏度降低,溶解度和透明度升高,扫描电镜观察到其表面结构疏松程度也升高,但随着取代度的升高,其透明度升高不明显;酯化后的亚麻胶起泡性能明显升高,但泡沫稳定性降低,乳化性明显下降.     

亚麻蛋白功能特性的研究

综合了有关亚麻蛋白含量、氨基酸组成、物理化学性质、功能特性方面的文献报道，重点叙述了有关亚麻蛋白在简单体系和几种食品体系中的功能特性及其不同组分的物理化学特性。     

Mucilage in linseed: effects on the intestinal viscosity and nutrient digestion in broiler chicks

A study was conducted to obtain more information on the role of mucilage in the adverse effects produced by the use of linseed in chick diets. Mucilaginous material was extracted from linseed with hot distilled water (80 °C) for 2 h; after filtration the water‐soluble extract was freeze‐dried and ground. A maize/soyabean meal basal diet with supplemental linseed mucilage extract (0, 4, 8, 12 and 16 g kg^?1) was given to chicks from 8 to 28 days of age. During the last 3 days the excreta were collected quantitatively, then the chicks were slaughtered and the jejunal and ileal contents were collected. Feeding the mucilage extract‐containing diets to birds increased markedly, from 4.35 to 18.89 mPa s, the digesta viscosity at jejunal level. The apparent faecal digestibility of crude fat and major fatty acids and the dietary AMEn value (metabolisable energy corrected to zero nitrogen retention by the body) were linear and negatively influenced by the inclusion level of mucilage extract. However, the presence of mucilage in the diet did not affect the apparent ileal digestibility of crude protein and individual amino acids. These results seem to suggest that mucilage in linseed has lower antinutritional properties than those reported for whole linseed or linseed meal when included in chick diets. © 2002 Society of Chemical Industry     

Preparation and Functional Properties of Linseed Protein Products Containing Differing Levels of Mucilage

The functionality of two high-mucilage protein concentrates (HMPC) prepared from linseed and linseed expeller cake by extracting and coprecipitating the mucilage with protein was compared with those of a low-mucilage flour (LMF), a protein concentrate (LMPC), and a protein isolate (LMPI) in simple systems. The HMPC samples had better water absorption and emulsifying properties, higher foaming capacity, but lower nitrogen solubility, oil absorption, and foam stability than LMF and LMPC. They also registered higher values of viscosity and emulsification characteristics than LMPI.     

EMULSIFYING PROPERTIES OF ETHANOL-PRECIPITATED MUCILAGE FROM CELLULASE-HYDROLYZED GREEN ALGAE (MONOSTROMA NITIDUM)

The emulsifying properties of the ethanol‐precipitated mucilage from cellulase‐hydrolyzed Monostroma nitidum were investigated. Both emulsifying activity and emulsion stability of the mucilage increased from 51.5 and 48.0% to 69.0 and 62.0%, respectively, and oil droplets did not coalesce when the mucilage concentration was at l%(w/v). Gel permeation chromatography showed that the carbohydrate moieties of the mucilage exhibited an absence of low molecular weight fractions and a broader molecular weight range for the high molecular weight fraction than that of the cellulase hydrolysate. Also, there was a greater amount of high molecular weight protein‐containing fractions in the mucilage, while predominantly low molecular weight protein fractions were in the hydrolysate. Increasing the mucilage concentration of the solution(0–20 mg/mL) led to a reduction of surface tension to 54.9 dyne/cm, and increased the emulsifying activity and emulsion stability to 76.9 and 70.0%, respectively. The oil did not separate from the emulsion when the mucilage concentration was higher than 0.5%(w/v). When 0.2% NaCl was added to the emulsion containing 1% mucilage, the apparent viscosity decreased from 37.1 to 7.6 Pa.s (x 10^‐3). Also, the emulsifying activity and emulsion stability decreased from 69.0 and 62.0% to 50.0 and 48.0%, respectively.     

Development of Resource-Saving Technology of Linseed Harvesting

ABSTRACT

The traditional technology of linseed harvesting involves the cutting of the stems with subsequent threshing. During cutting part of the stem remains on the field, which causes significant losses of fibrous raw materials. Threshing of stems by traditional technology also causes significant damage to the linseed straw. Developed resource-saving technology of linseed harvesting provides first linseed thrashing on the plants with subsequent pulling of stems. With this sequence of technological operations, all linseed stems and seeds are preserved without damage. For the implementation of resource-saving technology proposed design of flax thresher and flax puller. The results of experimental studies of the properties of linseed fibre obtained from the linseed showed that such fibre is suitable for the production of non-woven materials, technical textiles and paper. The introduction of resource-saving technology of linseed harvesting will save the harvest of seeds and straw with minimal losses and damage. Resource-saving technology will increase the profitability of linseed cultivation.     

利用紫虫胶制备亚麻籽油凝胶油

以亚麻籽油为油基、紫虫胶为凝胶因子,用加热搅拌和冷却的方法制备亚麻籽油凝胶油,研究不同工艺条件对亚麻籽油凝胶油持油性、结晶形成时间、硬度的影响。将虫胶添加量、加热时间和加热温度作为自变量,凝胶油的持油性作为响应值,进行响应面优化试验。通过试验得到亚麻籽油凝胶油的最佳工艺:虫胶添加量8%、加热温度79℃、加热时间25 min。此工艺条件下的亚麻籽油凝胶油持油性为84.92%。对比分析亚麻籽油凝胶油和市售黄油的热力学性质、晶体形态,发现该凝胶油和市售黄油的熔点相近,且凝胶油具有一定塑性。     

不同方法提取胡麻油性质的对比研究

采用Schaal烘箱法对不同方法提取的胡麻油的氧化性质进行了对比研究。试验结果表明:由3种方法提取的胡麻油的自氧化试验可知,过氧化值变化由大到小为冷榨胡麻油、超临界CO2提油、溶剂提油。碘值变化从大到小的顺序为超临界提油、冷榨胡麻油、溶剂提油;酸值变化从大到小的顺序为超临界提油、溶剂提油、冷榨胡麻油;黏度变化从大到小的是超临界提油、冷榨胡麻油、溶剂提油。3种胡麻油中特征值变化最大的是超临界CO2提取的胡麻油。     

基于核磁共振技术对亚麻籽油进行脂肪酸组成检测与品质鉴别

采用核磁共振(NMR)技术对山西省内生产的亚麻籽油进行脂肪酸组成检测及品质鉴别。首先运用气相色谱-质谱联用(GC-MS)法确认纯亚麻籽油和掺杂亚麻籽油脂肪酸组成的差异;然后通过核磁共振谱仪确认差异核磁共振氢谱（1H NMR）和碳谱（13C NMR）的特征峰,以快速判别亚麻籽油是否掺杂;最后,采用1H NMR法计算亚麻籽油中的脂肪酸含量,并与国标GC法进行对比。结果表明：与纯亚麻籽油相比,掺杂亚麻籽油中含有花生一烯酸和芥酸;通过花生一烯酸和芥酸1H NMR和13C NMR特征峰可以定性鉴别亚麻籽油是否掺杂;采用1H NMR法计算的亚麻籽油中亚麻酸含量与GC法一致。说明基于NMR技术对亚麻籽油脂肪酸组成进行检测,可以快速鉴别亚麻籽油品质。     

Linear relationship between increasing amounts of extruded linseed in dairy cow diet and milk fatty acid composition and butter properties

The aim of this experiment was to compare the effects of increasing amounts of extruded linseed in dairy cow diet on milk fat yield, milk fatty acid (FA) composition, milk fat globule size, and butter properties. Thirty-six Prim’Holstein cows at 104 d in milk were sorted into 3 groups by milk production and milk fat globule size. Three diets were assigned: a total mixed ration (control) consisting of corn silage (70%) and concentrate (30%), or a supplemented ration based on the control ration but where part of the concentrate energy was replaced on a dry matter basis by 2.1% (LIN1) or 4.3% (LIN2) extruded linseed. The increased amounts of extruded linseed linearly decreased milk fat content and milk fat globule size and linearly increased the percentage of milk unsaturated FA, specifically α-linolenic acid and trans FA. Extruded linseed had no significant effect on butter color or on the sensory properties of butters, with only butter texture in the mouth improved. The LIN2 treatment induced a net improvement of milk nutritional properties but also created problems with transforming the cream into butter. The butters obtained were highly spreadable and melt-in-the-mouth, with no pronounced deficiency in taste. The LIN1 treatment appeared to offer a good tradeoff of improved milk FA profile and little effect on butter-making while still offering butters with improved functional properties.     

Effects of dietary supplementation with extruded linseed and oregano in autochthonous goat breeds on the fatty acid profile of milk and quality of Padraccio cheese

The study aimed to evaluate the effects of linseed and oregano supplementation to the diet of goats on fatty acid profile and sensory properties of Padraccio, a typical cheese produced during spring through summer in the Basilicata region (southern Italy). Extruded linseed and dried oregano inflorescences were integrated in the pelleted concentrate supplementation (500 g/head per day) in 21 grazing goats that were randomly assigned, 7 per group, to the following experimental treatments: concentrate, concentrate with addition of linseed, and concentrate with addition of linseed and oregano. Pooled milk from each group was used in cheesemaking. From a nutritional perspective, integration of extruded linseed in the goat diet improved the fatty acid profile of Padraccio cheese. Moreover, the cheese from this group evidenced the highest scoring on color, flavor, texture, and overall liking.     

Effects of chemically or technologically treated linseed products and docosahexaenoic acid addition to linseed oil on biohydrogenation of C18:3n-3 in vitro

Rumen biohydrogenation kinetics of C18:3n-3 from several chemically or technologically treated linseed products and docosahexaenoic acid (DHA; C22:6n-3) addition to linseed oil were evaluated in vitro. Linseed products evaluated were linseed oil, crushed linseed, formaldehyde treated crushed linseed, sodium hydroxide/formaldehyde treated crushed linseed, extruded whole linseed (2 processing variants), extruded crushed linseed (2 processing variants), micronized crushed linseed, commercially available extruded linseed, lipid encapsulated linseed oil, and DHA addition to linseed oil. Each product was incubated with rumen liquid using equal amounts of supplemented C18:3n-3 and fermentable substrate (freeze-dried total mixed ration) for 0, 0.5, 1, 2, 4, 6, 12, and 24 h using a batch culture technique. Disappearance of C18:3n-3 was measured to estimate the fractional biohydrogenation rate and lag time according to an exponential model and to calculate effective biohydrogenation of C18:3n-3, assuming a fractional passage rate of 0.060/h. Treatments showed no differences in rumen fermentation parameters, including gas production rate and volatile fatty acid concentration. Technological pretreatment (crushing) followed by chemical treatment applied as formaldehyde of linseed resulted in effective protection of C18:3n-3 against biohydrogenation. Additional chemical pretreatment (sodium hydroxide) before applying formaldehyde treatment did not further improve the effectiveness of protection. Extrusion of whole linseed compared with extrusion of crushed linseed was effective in reducing C18:3n-3 biohydrogenation, whereas the processing variants were not different in C18:3n-3 biohydrogenation. Crushed linseed, micronized crushed linseed, lipid encapsulated linseed oil, and DHA addition to linseed oil did not reduce C18:3n-3 biohydrogenation. Compared with the other treatments, docosahexaenoic acid addition to linseed oil resulted in a comparable trans11,cis15-C18:2 biohydrogenation but a lesser trans10+11-C18:1 biohydrogenation. This suggests that addition of DHA in combination with linseed oil was effective only in inhibiting the last step of biohydrogenation from trans10+11-C18:1 to C18:0.