油料挤压膨化机的正确选用

目前 ,我国大多数油脂厂均采用浸出法制油。油脂的生产过程一般包括油料预处理、浸出、精炼等工序。其中 ,油料预处理在整个工艺中具有十分重要地位 ,对油脂的品质、提取率、生产效率等影响较大。传统的油料预处理方法由于对轧胚工艺要求高、浸出效率低逐渐被新的挤压膨化预处理技术所代替。早在 2 0世纪 60年代 ,美国、巴西已开始采用挤压膨化预处理工艺浸出制油 ,由于油料经挤压膨化后 ,容重增大 ,并呈微孔状 ,其渗透性被大大提高 ,浸出溶剂的通过料层速度也大大加快 ,由此 ,浸出器的生产能力被显著提高 ,而且大大降低了浸出溶剂回收能耗。所以 ,随着人们对油料挤压膨化技术在油脂生产中应用优势的认识 ,近年来挤压膨化技术被广泛地应用于油脂和饲料的生产 ,为此 ,本文就油料挤压膨化机合理选用及其正确使用等进行论述 ,为厂家正确应用油料挤压膨化机提供指导性意见 ,使油料膨化技术在生产中真正起到作用 ,达到增产、降耗、提高浸出效率之目的。     

油料挤压膨化机的正确选用

目前，我国大多数油脂厂均采用浸出法制油。油脂的生产过程一般包括油料预处理、浸出、精炼等工序。其中，油料预处理在整个工艺中具有十分重要地位，对油脂的品质、提取率、生产效率等影响较大。传统的油料预处理方法由于对轧胚工艺要求高、浸出效率低逐渐被新的挤压膨化预处理技术所代替。早在20世纪60年代，美国、巴西已开始采用挤压膨化预处理工艺浸出制油，由于油料经挤压膨化后，容重增大，并呈微孔状，其渗透性被大大提高，浸出溶剂的通过料层速度也大大加快，由此，浸出器的生产能力被显著提高，而且大大降低了浸出溶剂回收能耗。所以，随着人们对油料挤压膨化技术在油脂生产中应用优势的认识，近年来挤压膨化技术被广泛地应用于油脂和饲料的生产，为此，本文就油料挤压膨化机合理选用及其正确使用等进行论述，为厂家正确应用油料挤压膨化机提供指导性意见，使油料膨化技术在生产中真正起到作用，达到增产、降耗、提高浸出效率之目的。     

试谈我国油脂工业发展前景

本文根据近年来国内外油脂科技发展动态,结合我国实际情况,从油脂制取及加工、油料植物蛋白的开发、油厂副产品综合利用等三个方面展望我国油脂工业发展前景。并着重评述:油料挤压膨化预处理及饼粕挤压膨化脱毒;几种保健营养油脂的开发;以蛋白产品的应用来促进大豆蛋白产品的生产;水剂法与膜分离相结合的油料蛋白工艺;膜技术在油脂工业中应用;短键醇类对棉籽的浸出及棉籽饲用蛋白。     

油料膨化浸出

油料膨化浸出在国外早有应用 ,我国膨化浸出技术的开发在 2 0世纪80年代中期 ,主要用于大豆浸出工艺中 ,但由于国内设计的膨化机在物料膨化性能上与浸出要求相差较大 ,致使大豆膨化技术没能广泛推广。可喜的是引进美国大豆膨化机后 ,我国先后消化吸收国外技术在国内试生产 ,生产的豆粕质量也被市场接受 ,所以近几年膨化浸出在国内已经得到初步的应用。但由于油脂生产企业对膨化浸出的优越性还没有足够的认识 ,因此影响了膨化浸出的推广应用。郑州四维膨化技术有限公司是国内集油脂设备制造、工程设计以及技术服务为一体的专业技术公司 ,在膨…     

挤压膨化—一种油料预处理新工艺

油料在浸出前进行挤压膨化,是一种预处理新工艺。本文对挤压机的结构及工作原理,挤压膨化后料粒结构的变化及其对制油工艺的影响等进行了评述。此外,对这种新工艺在我国是否适用也进行了探讨。     

膨化技术在油脂浸出中的应用

膨化技术在油脂浸出中的应用杜连起在通常的浸出法制油过程中，对油料进行预处理的目的是尽可能地破坏油料细胞，并形成利于制油的几何形状。为了获得良好的浸出效果，要求料胚片薄而均匀、粉末度小，然而这始终是相互矛盾的，要解决这一矛盾并不容易。近年来，利用膨化技...     

油料预处理对油脂品质影响的研究进展

油料预处理是油脂加工中一个重要的环节,对油脂的质量和风味有着重要的影响。为探究不同预处理技术对油脂质量和风味的影响,综述了不同油料在加工中的不同预处理技术,重点分析脱皮、高温烘烤、微波、挤压膨化、脉冲电场、红外线烘烤及超声波等油料预处理技术对油脂品质的影响,并探讨了油料预处理技术的发展方向。不同预处理技术对油脂品质的影响各不相同,多种油料预处理技术协同应用的加工艺具有较大的发展潜力。     

挤压膨化对大豆磷脂的影响

简述挤压膨化技术及其在油脂生产中的应用，挤压膨化对制取大豆磷脂的影响。采用挤压膨化预处理工艺制取油脂可以提高毛油的脱胶效率，改善油的品质，增加磷脂的得率，增强磷脂的性能。     

油料挤压膨化预处理对油脂的影响

近年来,油料的挤压膨化预处理已受到了我国油脂工作者的重视,作为一种新的油料预处理工艺,显示出其现有预处理工艺难以达到的优越性,将会推动我国油脂工业的发展。本文主要就挤压过程对油脂的化学变化和品质影响进行评价,并探讨挤压过程中控制油脂氧化的方法。     

大豆挤压膨化物显微结构的研究

针对大豆挤压膨化预处理浸油时,浸出率提高,浸出时间缩短这一现象进行研究,应用了樾的显微技术中的石蜡制片法和显微摄影技术,分别对大豆挤压膨化物和大豆轧胚胚片制成切片,切片染色后显微摄影。指出大豆挤压膨化预处理较轧胚预处理具有明显的优势。     

Localization and steroid regulation of prostaglandin E2 receptor protein expression in ovine cervix

Although prostaglandin E2 (PGE2) has been identified as a central mediator of the cervical ripening process, the mechanisms responsible for PGE2 ripening are still poorly understood, partly because of the lack of information concerning the precise cellular localization and regulation of PGE2 (EP) receptors in the cervix. To provide new insights into the mechanisms of cervical ripening, we used indirect immunofluorescence to localize cervical EP receptor protein expression in ovariectomized ewes and examined the effect of administration of progesterone or estradiol. EP receptors were widely distributed in cervical blood vessels, epithelium of the cervical canal, circular and longitudinal muscles, and stroma. Estradiol replacement decreased EP1 and EP3 receptor protein in blood vessel media (by 23 and 31% respectively, P < 0.05) and decreased EP1 receptor protein expression in the longitudinal muscle layer (by 27%, P < 0.05). Stromal EP1 and EP3 receptor protein expression was also reduced by estradiol (by 29 and 20% respectively, P < 0.05). Progesterone replacement had no significant effect on EP receptor protein expression. The arterial changes would favor PGE2-induced vasodilatation, subsequent edema and leukocyte infiltration during the cervical ripening process whereas the muscular alterations would facilitate smooth muscle relaxation and cervical dilatation. Furthermore, estradiol provoked perinuclear localization of EP3 receptor protein in the longitudinal muscle layer. This latter result suggests that cellular EP receptor localization is regulated by estradiol and that PGE2 may also control smooth muscle contraction and regulate ovine cervical dilatation in an intracrine manner via EP3 receptors.     

Immunomodulatory and antioxidant potential of Lactobacillus exopolysaccharides

BACKGROUND: Immunomodulation by probiotic microorganisms has become a topic of increasing interest in food microbiology. Polysaccharides are broadly used in the food industry as gelling, thickening, stabilizing, or emulsifying agents. Some probiotics such as lactic acid bacteria also produce exopolysaccharides that stimulate macrophage production of cytokines. The aim of this study was to characterize the effects of exopolysaccharides of Lactobacillus paracasei subsp. paracasei NTU 101 (101EP) and Lactobacillus plantarum NTU 102 (102EP) exopolysaccharides on antioxidant activity and immunomodulation in vitro. RESULTS: The sugar composition (including arabinose, galactose, glucose, fructose, mannose, and maltose) of 101EP and 102EP was quantified by high‐performance anion‐exchange chromatography. Cytokine production (including IL‐6, TNF‐α, and IL‐1β) was induced by 101EP and 102EP in Raw 264.7 in a dose‐dependent manner (5‐500 µg mL^?1). 101EP and 102EP also demonstrated potential antioxidant properties (1,1‐diphenyl‐2‐picrylhydrazyl radical scavenging activity, chelation of ferrous ions, inhibition of linoleic acid peroxidation, and reducing power) in vitro. CONCLUSION: 101EP and 102EP stimulate cell proliferation and may be useful as a mild immune modulator of macrophages. Copyright © 2011 Society of Chemical Industry     

Modification methods and applications of egg protein gel properties: A review

Egg protein (EP) has a variety of functional properties, such as gelling, foaming, and emulsifying. The gel characteristics provide a foundation for applications in the food industry and research on EP. The proteins denature and aggregate to form a dense three-dimensional gel network structure, with a process influenced by protein concentration, pH, ion type, and strength. In addition, the gelation properties of EP can be altered to varying degrees by applying different treatment conditions to EP. Currently, modification methods for proteins include physical modification (heat-induced denaturation, freeze–thaw modification, high-pressure modification, and ultrasonic modification), chemical modification (glycosylation modification, phosphorylation modification, acylation modification, ethanol modification, polyphenol modification), and biological modification (enzyme modification). Pidan, salted eggs, egg tofu, and other egg products have unique sensory properties, due to the gel properties of EP. In accessions, EP has also been used as a new ingredient in food packaging and biopharmaceuticals due to its gel properties. This review will further promote EP gel research and provide guidance for its full application in many fields.     

Antioxidant activity of peanut seed testa and its antioxidative component,ethyl protocatechuate

The antioxidant activity of ethanolic extracts of peanut seed testa (EEPST) and its antioxidative component, ethyl protocatechuate (EP), was examined. It was found that EEPST and EP showed a dose-dependent activity on the inhibition of liposome peroxidation. EEPST and EP in the range of 50–500 mg/l were effective in protecting protein against oxidative damage. EEPST and EP at 100 mg/l showed 92.6% and 84.6% scavenging effect, respectively, on α,α-diphenyl-β-picrylhydrazyl radical, indicating that they act as a primary antioxidant. In addition, EEPST and EP, at a dose of 200 mg/l, showed 70.6% and 67.7% scavenging effect, respectively, on the hydroxyl radical. EEPST also exhibited a metal-binding ability, while EP did not. The inhibitory effect of EEPST on linoleic peroxidation correlated with their polyphenolic content. These results suggest that the antioxidant mechanism, for both EEPST and EP, could possibly be due to their scavenging effect on free radical and hydroxyl radical. In addition, its metal binding ability may contribute to antioxidant activity of EEPST.     

2种鸡肉蛋白源酶解产物抗氧化活性研究

以鸡肉盐溶蛋白和肌纤蛋白为原料分别制备的酶解物EP1和EP2,对其分子量分布、游离氨基酸,以及还原力、·OH自由基、O_2~-·自由基和DPPH·自由基清除力等抗氧化活性进行分析。研究结果显示EP1和EP2分子量均在5000以下,其分子量介于180～1000u的组分分别为66.32%和54.74%,寡肽含量达57.79%和47.70%。游离氨基酸分析结果显示除20种常规氨基酸,EP1和EP2还含有多种非常规氨基酸,如γ-氨基丁酸、牛磺酸、肌肽、磷酸丝氨酸等;另外,碱性氨基酸(26.01%和29.43%)和疏水氨基酸(38.00%和32.88%)含量均较高。EP1和EP2均具有较强的总还原力、·OH自由基清除能力、O_2~-·自由基清除力和DPPH·自由基清除能力,也就是同时具有供电子体和供氢体清除自由基的能力。EP1和EP2的高抗氧化活性是由寡肽及氨基酸共同作用的结果。     

Effect of Echinacea purpurea L. on oxidative status and meat quality in Arbor Acres broilers

BACKGROUND: Echinacea purpurea L. (EP) is a popular herbal antioxidant and immunomodulator. The present study was conducted to evaluate the effects of EP on meat quality and oxidative status in broilers. Two hundred and fifty (1‐day‐old) male broilers (Arbor Acres) were randomly allocated to five groups including the control (corn‐soybean meal diet) and 0.1, 0.5, 1.0 and 2.0% EP powder groups, with two replicates per treatment group. RESULTS: The results indicated that the addition of 0.5% and 1.0% EP significantly increased water‐holding capacity and decreased storage loss of breast and thigh fillets at 35 days old. For fillet colour, L* (lightness) values were lower, and a* (redness) and b* (yellowness) values were higher with EP supplementation. Lower crude fat contents were observed in EP groups in comparison with control at 35 days of age in breast and thigh fillets, respectively. Production of malondialdehyde was slightly reduced in serum of EP supplemented birds compared to the control group. Results for Trolox equivalent antioxidant capacity, catalase and superoxide dismutase were significantly higher for the 0.5, 1.0 and 2.0% EP supplemental groups than control group in serum. Liver and spleen tissues results showed that the antioxidative enzymes activities were higher with EP powder at 35 days of age. CONCLUSION: Dried EP can be used as a feed additive to improve the meat quality and oxidative status in Arbor Acres broilers. Copyright © 2012 Society of Chemical Industry     

Evaluation of physicochemical properties and microbial counts of raw and cooked low-fat patties added with eggplant powder prepared with different drying methods

Effects of different drying methods and different addition levels of eggplant (EP) on product quality of low-fat patties (LFPs) were investigated during storage. EP was dried in an oven dryer at 60 °C or a freeze dryer at −50 °C. LFPs were prepared by replacing with 1.5% soy protein isolate (SPI). Six treatments were used in this study: (1) control (CTL), without addition of EP; (2) reference (REF), 0.1% ascorbic acid; (3) O1, 0.25% oven-dried (OD) EP; (4) O2, 0.5% ODEP; (5) F1, 0.25% freeze-dried (FD) EP; and (6) F2, 0.5% FDEP. Redness (a*) and lightness (L*) values in LFPs added with EP were lower than those of others (p < 0.05) and decreased with increasing storage time. Yellowness (b*) values of cooked patties were increased during storage time (p < 0.05), with control having the highest value. The addition of EP or ascorbic acid into LFPs lowered microbial counts than control (p < 0.05). Thiobarbituric acid reactive substances (TBARS) was increased during storage, with REF having the lowest value, and patties added with EP had lower TBARS values than control during storage. Volatile basic nitrogen (VBN, mg%) contents of all patties also increased during storage time with O2 and F2 having lower values than control. Therefore, EP might have potential as a natural antioxidant in meat products during storage.     

Enzymatic Browning of Model Solutions and Apple Phenolic Extracts by Apple Polyphenoloxidase

Model solutions containing chlorogenic acid (CG) and (-)-epicatechin (EP), and phenolics from nine apple cv., were oxidized with apple polyphenoloxidase (PPO). Browning was determined by absorbance at 380–700 nm, and transformed into CIE L*, a* and b*. Multilinear correlations were established between initial and degraded amounts of each phenolic. In model solutions of CG and EP, color values and A₄₀₀ correlated strongly with initial and oxidized CG and EP. Both phenolics contributed to decrease in L* and increase in A₄₀₀. Increase ii CG increased a*, but EP had little effect. The imnact of increased EP on b* was two to three times higher than for CG_: In each phenol class (hydroxycinnamic (HD), flavan-3-ol (FA), flavonol (FO) and dihydrochalcone (DC) derivatives), degraded amounts were increased or decreased by increasing amounts of other classes. Besides major phenolics, HD (mainly CG) and FA (mainly EP and procyanidin B2), FO and DC, appeared to affect color development.     

余甘子多酚对油炸方便面品质的影响

利用LSA-10大孔吸附树脂纯化余甘子多酚提取物,将纯化后的多酚加入面粉中制作油炸方便面,采用HPLC测定方便面中主要多酚物质的含量,考察余甘子多酚(EP)对油炸方便面蒸煮特性、质构特性及油脂氧化的影响.结果表明,余甘子多酚中主要的多酚物质为没食子酸(EA)、柯里拉京和鞣花酸,含量分别为(45.2±0.1)、(16.6...     

New ecological nixtamalisation process for tortilla production and its impact on the chemical properties of whole corn flour and wastewater effluents

An ecological nixtamalisation process (EP) for making whole corn flour for tortillas was compared with the traditional nixtamalisation process (TP). One of the problems of TP is high level of solid losses. The aim was to evaluate the composition of these losses. In EP, dry matter losses of nejayote were from 1.2% to 1.4%, while in TP 3.2%. Nejayote from TP showed a pH of 11.9, whereas EP showed a pH close to neutral. The pericarp was retained in EP with the use of calcium salts, whereas in TP lime destroyed it almost completely. Losses of total dietary fibre in nejayote solids were about 41.2% for TP compared to an average of 17.4% for EP. Most of nejayote losses in TP were soluble fibre (30.4%), compared with EP that ranged from 6.2% to 7.9%. All compounds retained by nixtamal from EP are important sources of nutrients and dietary fibre.