蔗糖酯的合成工艺及其应用研究

作为一种新型的表面活性剂 ,蔗糖酯具有广泛的工业用途。本文综述了国内外蔗糖酯的研究进展 ,包括蔗糖酯的合成工艺、纯化检测方法、工业用途和开发现状 ,最后还提出了蔗糖酯的研究开发设想     

蔗糖脂肪酸酯的制备及应用研究进展

蔗糖脂肪酸酯简称蔗糖酯,是一种良好的表面活性剂,被普遍应用于食品工业。蔗糖酯的合成方法主要包括化学法和酶法,对蔗糖酯的化学合成法进行了详细介绍,概述了酰氯酯化法及酯交换法的操作步骤、优选工艺及优缺点,并与酶法进行了对比。概述了蔗糖酯的结构、理化性质、应用及工业发展现状,以期为蔗糖酯的工业化生产提供参考。     

糖基天然表面活性剂的合成研究进展(上)

蔗糖酯是一类性能优良具有广泛用途的糖基天然表面活性剂,近10年在制糖工业得到普及应用.本文综述蔗糖酯的合成方法及研究进展并提出开发建议.     

蔗糖多酯的合成研究进展

蔗糖多酯（SPE）是一种新兴的功能性食品添加剂,具有广阔的发展前景。它作为一种新的脂肪替代品,在不久的将来必定会在食品工业中得到大规模的推广和应用。本文综述了蔗糖多酯的营养保健功能、工业用途和合成方法的国内研究进展情况,提出了蔗糖多酯的开发设想。     

蔗糖脂肪酸酯在乳化抑菌方面的应用研究进展

蔗糖脂肪酸酯是由蔗糖和脂肪酸合成的具有各种亲水亲油性质的安全无毒、可生物降解的非离子型表面活性剂。由于具有良好的乳化、分散、增溶、润滑、抑菌等性能,使之在工业中的各个领域具有广阔的应用。在本文介绍了蔗糖脂肪酸酯的理化性质、合成方法,综述了蔗糖酯作为乳化剂和抑菌剂的应用进展,并对其应用前景进行了展望。     

反丁烯二酸蔗糖甲酯合成及乳化特性研究

以固体超强酸SO42-/TiO2为催化剂,一锅法合成了反丁烯二酸蔗糖甲酯。乳化特性研究表明:酯化度为5.5的反丁烯二酸蔗糖甲酯的HLB值为6.8、临界胶束浓度为0.7g/L、浓度为0.3%溶液的表面张力为28.5mN/m,说明反丁烯二酸蔗糖甲酯具有一定的表面活性。反丁烯二酸蔗糖甲酯的乳化活性介于蔗糖酯和Span-80之间,比蔗糖酯要好。大于临界胶束浓度时,反丁烯二酸蔗糖甲酯、蔗糖酯和Span-80均有较高的乳液稳定性。有关反丁烯二酸蔗糖甲酯与其它乳化剂的复配性能及其在日用化学工业及食品等领域的应用有待于进一步研究。     

新型乳化剂在咖啡乳饮料中的应用研究

蔗糖脂肪酸酯在咖啡乳饮料中能够提供良好的乳化性能,同时蔗糖脂肪酸酯能够提供抑制耐热性芽孢杆菌作用的性能。本探究针对蔗糖脂肪酸酯在咖啡乳饮料发挥的重要性能,通过选用了不同类型的乳化剂进行研究。通过进行单因素实验和长期观察,探究是否有乳化剂能有效取代蔗糖脂肪酸酯在咖啡乳饮料中的添加使用。研究结果表明,对于蔗糖脂肪酸酯在咖啡乳饮料的使用,使用新型聚甘油脂肪酸酯PD能够在稳定性能和乳化性能上取代蔗糖脂肪酸酯的添加;而在针对耐热性芽孢的抑制性能上,PD在实验到本文攒写期间内表现的效果与蔗糖脂肪酸酯的效果无明显差异,没发生任何变败,但是在目前的实验阶段中,样品仍在静置观察中,对于PD抑制芽孢性能的作用仍需继续观察,同时,新型聚甘油脂肪酸酯PD在咖啡乳饮料的添加量与蔗糖脂肪酸酯的添加量为一致,较大程度减少原料成本。     

RYOTO蔗糖酯在油脂产品中的应用

<正> RYOTO蔗糖酯是由蔗糖和天然植物脂肪酸通过酯化合成的具有安全性的非离子表面活性剂。RYOTO蔗糖酯是在蔗糖的羟基上由脂肪酸进行酯化结合的产品:1个蔗糖的分子,总共有8个羟基。理论上,其结合范围可以从1个蔗糖分子与1个脂肪酸结合的单酯产品到1个蔗糖分     

茉莉酸甲酯对烟叶表面腺毛密度及蔗糖酯含量的影响

以烟草栽培品种K326、龙江911和翠碧1号3个品种为供试材料,利用组织化学染色法在体视显微镜下观察分泌蔗糖酯腺毛数,测定了蔗糖酯含量。研究了不同浓度的茉莉酸甲酯(MeJA)对烟草表面单位面积上蔗糖酯的相对含量及分泌蔗糖酯腺毛密度的影响。结果显示,4个浓度的MeJA处理中,3个品种的烟草表面蔗糖酯含量及蔗糖酯分泌腺毛密度随着MeJA浓度的增加而逐渐降低。烟草的这种反应对其合理分配代价、形成对害虫强有力的抗性可能更为有利。     

脂肪酸蔗糖酯化学分析方法探讨

目前,国内不少单位都在研制脂肪酸蔗糖酯,但市场上的产品往往不标明蔗糖酯的含量,且绝大部分产品的总蔗糖酯含量只占1/3,而皂和其他非活性成份各占1/3。作者借鉴国外资料,摸索出一种不需复杂仪器、不需标准样、而又行之有效的脂肪酸蔗糖酯的定量分析方法,介绍如下。分析方法采用不同的工艺和配方生产的脂肪酸蔗糖酯,其分析方法略有差别,下面分别论述。     

Effect of pre-incubation conditions on growth and survival of Staphylococcus aureus in sliced cooked chicken breast

In this work, the effect of pre-incubation conditions (temperature: 10, 15, 37°C; pH 5.5, 6.5 and water activity, a(w): 0.997, 0.960) was evaluated on the subsequent growth, survival and enterotoxin production (SE) of Staphylococcus aureus in cooked chicken breast incubated at 10 and 20°C. Results showed the ability of S. aureus to survive at 10°C when pre-incubated at low a(w) (0.960) what could constitute a food risk if osmotic stressed cells of S. aureus which form biofilms survive on dried surfaces, and they are transferred to cooked meat products by cross-contamination. Regarding growth at 20°C, cells pre-incubated at pH 5.5 and a(w) 0.960 had a longer lag phase and a slower maximum growth rate. On the contrary, it was highlighted that pre-incubation at optimal conditions (37°C/pH 6.5/a(w) 0.997) produced a better adaptation and a faster growth in meat products what would lead to a higher SE production. These findings can support the adoption of management strategies and preventive measures in food industries leading to avoid growth and SE production in meat products.     

Effect of temperature on the growth response of Salmonella enteritidis inoculated onto the vitelline membranes of fresh eggs

The growth response of Salmonella Enteritidis (SE) on the vitelline membrane in vitro was studied with the use of a special tube devised specifically for the inoculation of SE onto the vitelline membrane and for the sampling of the yolk near the inoculation site. This latter ability allowed the detection of the movement of SE into the yolk. The growth of SE on the membrane was compared with that of SE inoculated into yolk and albumen in vitro and in ovo in fresh in-shell eggs. The incubation time was 2 days, and the incubation temperatures were 4, 8, 15, 27, and 37 degrees C. Comparison of the results obtained for in vitro growth showed that at 4, 8, and 15 degrees C, SE behaved as if it were in the albumen, with its numbers decreasing over time. At 27 and 37 degrees C, SE grew as if it were in yolk, with a maximum increase of 4.5 log CFU after 2 days at 37 degrees C. In no experiments involving growth on the vitelline membrane did SE appear in the yolk. Comparisons between in vitro and in ovo growth responses of SE in yolk and albumen indicate that SE growth on the membrane parallels that in the in-shell egg.     

Simple and rapid methods for detecting Salmonella enteritidis in raw eggs

The Centers for Disease Control and Prevention estimates there were 300,000 cases of Salmonella enteritidis (SE) in 1997. Egg products were associated with many of the cases. To address this problem, many producers implemented flock surveillance of the SE situation at their facilities. A rapid and simple method for detecting SE from poultry samples is critical for the effective implementation of such testing strategies. A lateral flow device for the detection of SE utilized in this study was manufactured by Neogen, Lansing, MI. The test panel is a presumptive qualitative test system that detects only members of Group D1 Salmonella species. A series of studies were conducted to optimize the test procedure for raw eggs with different sample preparations. A novel antigen extraction method was developed for use with the test panel kit. The detection limit of the test panel kit was increased approximately tenfold when the extraction method was used. Detection of SE was 100% in raw egg pools inoculated with 10 SE cells per ml of egg and incubated at a 1:10 ratio in buffered peptone water (BPW) or tetrathionate brilliant green broth (TBG) for 24 h at 37 degrees C. The developed lateral flow test kit could provide a simple, rapid, and inexpensive method for egg producers and processors to test specifically for Salmonella group D1 serovars, such as SE, in egg samples.     

文化创意产业法律保护探析——以产业链及成果生成为主线

随着科技与经济的不断融合与发展,文化创意产业由于具有高附加值、高创新度、高科技含量的特征,已经显现出迅猛发展的势头。如何对这一产业进行法律保护。笔者认为,要综合运用我国现有的与文化创意产业有关的各种知识产权与相关法律保护手段,将著作权、专利权、商标权、商业秘密权、反不正当竞争等与文化创意产业具有紧密联系的权益形态充分挖掘和利用,建立文化创意产业保护策略,为文化创意产业提供全方位的法律保护。     

Structural and Rheological Properties of Succinoglycan Biogums Made from Low-Quality Date Syrup or Sucrose Using Agrobacterium radiobacter Inoculation

This study examines and compares the structural and rheological properties of succinoglycan exopolysaccharide made by fermentation of sucrose or date syrup at identical temperature, pH, and total soluble solid. Using thin-layer chromatography (TLC), Fourier transform infrared (FTIR) spectroscopy, and rotational viscometery structural and rheological properties of prepared exopolysaccharides were assessed. The variables under studies were biogum concentrations (0.5%, 1.0%, 1.5%, and 2.0% w/w), temperature (5, 25 and 40°C), and pH (2.5, 4.0, 7.0, and 10.0). Results revealed that the quantity of exopolysaccharide produced in the date syrup (DSE) medium was three to five times greater than that of sucrose (SE) medium. The biogums exhibited non-Newtonian, shear-thinning behavior, and the viscosity of DSE was higher than SE at all tested concentrations. The TLC and FTIR spectroscopy assessments designated that the biogum is composed of glucose and galactose units, carrying a carboxylic group and indicated the presence of succinoglycan. The outcomes of this study could be useful to food industries seeking low cost biogum.     

Comparison of homogenization methods for recovering Salmonella Enteritidis from eggs

For Salmonella Enteritidis (SE) detection, shell eggs have been homogenized with stomachers, with electric blenders, and by hand massaging. However, to date, there have been no published reports addressing whether the method of homogenization affects the recovery of SE from raw eggs. Three inoculum levels (10, 126, and 256 SE cells per pool of 10 eggs) were used to conduct three experiments. The 10-egg pools were homogenized by one of four homogenization methods--mechanical stomaching, electric blending, hand massaging, and hand stirring-for 30 s. The homogenized eggs were then incubated at 37 degrees C, and SE colonies were enumerated after 24 and 48 h of incubation. After 24 h of incubation, no SE was recovered from egg samples from stomached or electrically blended pools inoculated with <10 cells, while levels of 106 CFU/ml were found for samples from whipped or hand-massaged pools inoculated with <10 cells. Similarly, after 24 h of incubation, the numbers of SE cells recovered from hand-massaged or hand-stirred egg pools inoculated with 126 cells were significantly larger than the numbers recovered from stomached or electrically blended egg pools inoculated with 126 cells. The number of SE cells recovered from samples homogenized with a blender was still significantly smaller than the numbers recovered from samples homogenized by the other three methods when the inoculum level was increased to 256 CFU per pool. However, the SE count for all samples approached 9 log10 CFU/ml after 48 h of incubation. It is concluded that the detection of small SE populations in shell egg samples could be improved with the use hand massaging and hand stirring for homogenization.     

Effect of pre-incubation conditions on growth and survival of Staphylococcus aureus in sliced cooked chicken breast

In this work, the effect of pre-incubation conditions (temperature: 10, 15, 37 °C; pH 5.5, 6.5 and water activity, a_w: 0.997, 0.960) was evaluated on the subsequent growth, survival and enterotoxin production (SE) of Staphylococcus aureus in cooked chicken breast incubated at 10 and 20 °C. Results showed the ability of S. aureus to survive at 10 °C when pre-incubated at low a_w (0.960) what could constitute a food risk if osmotic stressed cells of S. aureus which form biofilms survive on dried surfaces, and they are transferred to cooked meat products by cross-contamination. Regarding growth at 20 °C, cells pre-incubated at pH 5.5 and a_w 0.960 had a longer lag phase and a slower maximum growth rate. On the contrary, it was highlighted that pre-incubation at optimal conditions (37 °C/pH 6.5/a_w 0.997) produced a better adaptation and a faster growth in meat products what would lead to a higher SE production. These findings can support the adoption of management strategies and preventive measures in food industries leading to avoid growth and SE production in meat products.     

Response surface methodology for optimisation of soluble dietary fibre extraction from sweet potato residue modified by steam explosion

To make better use of sweet potato residue (SPR), a new pretreatment method, steam explosion (SE), can increase its content of soluble dietary fibre (SDF). Response surface methodology (RSM) was used to determine the SE variables for optimum SDF yield. The optimal conditions were a steam pressure of 0.35 MPa, a residence time of 121 s and a sieving mesh size 60. Under the optimised conditions, the content of SDF from SPR reached 22.59 ± 0.35%, an increase of 18.78% compared with that (3.81 ± 0.62%) from untreated SPR. The water‐holding capacity, oil‐holding capacity (OHC) and swelling capacity of SDF were improved by SE. Scanning electron micrograph (SEM) images demonstrated that SDF had become poriferous, loose and dilatants after SE treatment. This technology provides an efficient process for increasing the industrial production of SDF from SPR.     

二肽甜味剂-纽甜

本文比较全面地介绍了纽甜的发明、理化性质、使用特性和工业应用等。重点介绍了纽甜的功能特性以及在食品和其它行业中的应用。     

磁共振成像之SE序列在猪肉质量评估中的应用——TR值对成像质量的影响

本文论述了采用核磁共振成像技术（Magnetic resonance imaging，MRI）中的自旋回波（Spinecho，SE）序列对猪肉进行二维成像，从信号成像的质量效果入手，在改变重复时间（Repeat time，TR）值的情况下分析图像变化规律。利用一系列图像信号值拟合得出了所测猪肉的纵向弛豫时间T1范围，并发现了在SE序列成像过程中图像信号与T1之间有相关性。由此可推知，准确计算T1值时应采集相应TR值段的图像信号。而图像中脂肪与瘦肉两部分的对比度在此范围之内也是差别最大，这将有利于今后对猪肉进行NMR成像的质量分析的开展，提供了一种研究食品物质性质的方法。