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1.
The quality of shortenings, such as solid fat content (SFC) and texture, strongly depends on temperature fluctuations during storage and handling. The quality of a shortening might be affected not only by temperature fluctuations but also by its chemical composition and the presence of emulsifiers. The objective of this work was to investigate the effect of emulsifier addition and storage conditions on the texture, thermal behavior and SFC of low‐trans shortenings formulated with palm oil, palm kernel oil, and vegetable oils such as sunflower and soybean oils. Several conclusions can be drawn from this study: (a) The crystallization behavior of fat blends strongly depends on the type of emulsifier used and the chemical composition of the sample; (b) the addition of emulsifiers affects not only the type of crystals formed (fractionation) but also the amount of crystals obtained (enthalpy, SFC), inducing or delaying the crystallization process; (c) emulsifiers affect the texture of the crystalline structure formed by making it softer; (d) the storage conditions affect both the texture and the SFC of the materials. This study shows that samples that are highly super‐cooled during storage become harder while samples that are less super‐cooled become softer with storage conditions.  相似文献   

2.
Emulsifiers from Animal Fats The terms ?Emulsion”? and ?Emulsifier”? are defined and modified. Natural and synthetic emulsifiers used currently in foods are reviewed and mono-/diglyceride emulsifiers prepared from fats, which constitute a major portion of the products marketed, are discussed in details. Preparation, properties and applications of these emulsifiers in margarine, shortenings, ice creams and other foods are given. It is emphasized that animal fats, after refining and hardening, are highly suitable as starting material for the preparation of mono-/diglyceride emulsifiers having unobjectionable taste and good stability. These products are in no way inferior to those obtained from vegetable oils and fats.  相似文献   

3.
我国食品乳化剂的现状和展望   总被引:14,自引:0,他引:14  
杨辉荣  区国勇  宋晓锐  雷雨 《精细化工》2000,17(11):649-651
介绍了我国几类主要食品乳化剂———甘油脂肪酸酯、蔗糖脂肪酸酯、斯盘和吐温、大豆磷脂、硬脂酰乳酸钠和钙的生产和研究现状 ,并对我国食品乳化剂发展提出了几点建议。  相似文献   

4.
Consumers have come to expect many foods that can be served with minimum effort. Such convenience foods frequently require the use of emulsifiers in their formulations. Emulsifiers enable fatty and aqueous phases to be combined. Various emulsifiers have been developed to meet specific needs and have been judged adequately safe for their intended uses. Safety evaluation programs may include both feeding studies and metabolic studies. Feeding studies establish the levels at which a compound can be fed to experimental animals with no detectable ill effects. From this information, it is possible to estimate quantities that may be consumed safely by humans. Metabolic studies tell how a compound is handled by the body—whether it is burned for energy, stored, or excreted. The choice of studies to use in evaluating a specific compound depends upon the chemical nature of the compound, its similarity to familiar materials, and its intended use. Studies carried out with polysorbates and with monoglycerides are reviewed to illustrate these points and to show how safety testing programs yield the information needed for making sound safety judgments.  相似文献   

5.
Cake shortenings     
Triglycerides have been traditionally used in cakes to provide tenderness and grain. Specialty cake shortenings are used today to improve batter aeration, cake volume, grain, and to extend shelf life. The role of emulsifiers in providing improved shortening characteristics will be discussed. The features that will contribute to a quality cake shortening - manufacturing procedures, characteristics, and specifications - will be reviewed. Methods of use and handling will be related to cake quality.  相似文献   

6.
Summary One deficiency of liquid oils as all-purpose shortenings is their failure to cause the aeration in the mixing of conventional cake batters which is a normal function of the shortening ingredient. The addition of substantially insoluble, solid triglycerides in very finely divided form to liquid oils, with the object of improving their cake performance but not destroying fluidity, has been studied. Stearines made from rapeseed and mustardseed oils and certain peanut-oil fractions possessed the desired properties. The effective triglycerides in these stearines were of the monobehenodistearin and stearopalmitobehenin type.  相似文献   

7.
水性环氧乳化型固化剂(AEEC)乳化特性研究   总被引:1,自引:1,他引:0  
试验合成了一种水性环氧乳化型固化剂(AEEC),该固化剂是既亲水又亲油的两亲性化合物,除具有与环氧树脂(EP)的环氧基起交联反应的固化性能外,对液体EP具有良好的乳化能力。将AEEC与EP以适当比例混合,不加其它乳化剂,通过相反转法制备出稳定的EP水乳液。试验结果表明:在EP/AEEC固化剂/水三元体系中,当w(水)=30%~40%时,可以完成相反转过程;通过相反转法配制的乳液,乳液粒径小(1μm左右),粒径分布较窄,乳液稳定性良好;当固化剂成盐率为50%~60%时,乳液经离心(3 000 r/min)分离30 min不分层,固含量为10%的乳液室温静置一周不分层。  相似文献   

8.
Solid fat from fractionation of palm-based products was converted into cake shortening at different processing conditions. High oleic palm stearin with an oleic content of 48.2 % was obtained from fractionation of high oleic palm oil which was produced locally. Palm product was blended with different soft oils at pre-determined ratio and further fractionated to obtain the solid fractions. These fractions were then converted into cake shortenings named as high oleic, N1 and N2 blends. The physico-chemical properties of the experimental shortenings were compared with those of control shortenings in terms of fatty acid composition (FAC), iodine value (IV), slip melting point (SMP), solid fat content (SFC) and polymorphic forms. Unlike the imported commercial shortenings as reported by other studies and the control, experimental shortenings were trans-free. The SMP and SFC of experimental samples, except for the N2 sample, fell within the ranges of commercial and control shortenings. The IV was higher than those of domestic shortenings but lower when compared to imported and control shortenings. They were also observed to be beta tending even though a mixture of beta and beta' was observed in the samples after 3 months of storage. The shortenings were also used in the making of pound cake and sensory evaluation showed the good performance of high oleic sample as compared to the other shortenings.  相似文献   

9.
The sensory (odor and flavor) and physicochemical characteristics of tertiary butylhydroquinone (TBHQ) treated and butylated hydroxyanisole/toluene (BHA/BHT) treated liquid canola shortenings, subjected to accelerated storage (Schaal oven test at 65°C) and deep fat heating (at 185°C), were determined. Data for the Schaal oven test indicate that TBHQ was effective in retarding oxidative rancidity in liquid canola shortenings. However, addition of the commonly used mixture of BHA/BHT to canola shortenings resulted in only a slight decrease in oxidation during schaal oven storage. The results obtained from deep fat heating of canola liquid shortening show that neither TBHQ nor BHA/BHT was effective in enhancing oxidative and thermal stability of this product.  相似文献   

10.
Standard chemical procedures for the determination of glycerol, mono- and diglycerides in food products are lengthy, particularly when more than one component has to be determined in the same sample. Gaschromatographic techniques are applicable to these compounds when they are converted into their trimethylsilyl derivatives. A simple, rapid and quantitative gas chromatographic procedure has now been developed which is based on the addition of an internal standard (cholesteryl acetate) to samples which are subsequently silylated. This procedure has been applied to the direct determination of glycerol, mono- and diglycerides in emulsifiers, shortenings and other samples. Presented at the AOCS Spring Meeting, San Francisco, California, April 1969.  相似文献   

11.
Summary Carboxymethylmercapto succinic acid was one of the most effective metal inactivators examined for use in glyceride oils. The effectiveness is based on oxidative A.O.M. peroxide tests and on the organoleptic evaluation of various types of oils and shortenings. Indexes as high as 80-fold have been observed in preventing peroxide development. Extensive taste panel evaluations have shown significant improvements in the initial flavor and flavor stability of oils and shortenings treated with this mercapto acid. Indications are that the material has an extremely low order of toxicity. Acute tests have shown that the toxicity of the sodium salt is less than that of sodium citrate. The thermal instability to withstand deodorization temperatures and the possibility of the development of a mercaptan odor and taste in oils subjected to a high temperature is a serious disadvantage. Under some conditions the low order of fat solubility and the poisoning of hydrogenation catalyst would be detrimental in some oil-processing operations. Carboxymethylmercapto succinic acid and its derivatives may find use in salad oils, special hydrogenated oils for candy, icing, etc., vitamin preparations, drugs, and similar products where excellent trace metal-inactivating properties are required and where exposure to high temperatures is not encountered. Presented at the spring meeting of the American Oil Chemists’ Society, May 4–6, 1953, in New Orleans, La. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Service, U. S. Department of Agriculture.  相似文献   

12.
Lauryl sodium sulfate (LSS) combined with alkylphenol ethoxylates (APEO) were used to enhance the performance of a high starch content wood adhesive (HSWA). The optimal shear strength, mobility and viscosity stability of the wood adhesive after repeated freeze–thaw cycling were gained when LSS to APEO ratio was 7 to1, which could efficiently solve storage problems caused by a high starch content. Through blue value and differential scanning calorimetry (DSC) analysis, it was proved that the structure of the complexes formed between amylose and the compound emulsifiers with LSS/APEO mixing ration of 7:1 was the most stable. Scanning electron microscopy (SEM) images and particle size analysis showed that compound emulsifiers could significantly suppress the aggregation of emulsion particles. The mechanism could be, on the one hand, attributed to stable complexes formed by compound emulsifiers and amylose which could restrain starch retrogradation, and on the other to the synergetic effect of electrostatic charge forces and space steric hindrances caused by the LSS/APEO mixture adsorbed on the surface of latex particles. In conclusion, the addition of an LSS/APEO(mixing ratio 7:1) mixture could significantly prevent the aggregation of latex particles and retrogradation of starch molecules, indicating that these compound emulsifiers could be applied in the preparation of a high starch content wood adhesive.  相似文献   

13.
The compound 5-(tetradecyloxy)-2-furoic acid (TOFA), a hypolipidemic agent, inhibits fatty acid synthesis, lactate and pyruvate accumulation and CO2 release in isolated at adipocytes. TOFA stimulates the accumulation of citrate. ATP levels are not lowered by TOFA. In comparison with the natural fatty acid, oleate, TOFA exhibited a much greater inhibitory effect on lipogenesis. TOFyl-CoA formation within intact adipocytes was demonstrated. Although not inhibited by TOFA, acetyl-CoA carboxylase is inhibited by TOFyl-CoA. It is proposed that many of the metabolic effects of TOFA in isolated adipocytes can be explained by TOFyl-CoA inhibition of acetyl-CoA carboxylase. TOFA inhibits glycolysis as a secondary event with the primary event of inhibition of fatty acid synthesis causing an accumulation of citrate which is an inhibitor of phosphofructokinase.  相似文献   

14.
Effect of food emulsifiers on polymorphic transitions of cocoa butter   总被引:3,自引:0,他引:3  
The polymorphic behavior of cocoa butter in the presence of several food emulsifiers serving as crystal structure modifiers was investigated. Emphasis was placed on transitions among the relatively stable forms IV, V and VI, which are significant for a confectionery industry. As known from industry work, within the series of sorbitan esters and ethoxylated sorbitan esters, the solid emulsifiers were the most efficient in retarding transition of V form into VI modification. Blends of sorbitan monostearate (Span 60), ethoxylated sorbitan monostearate (Tween 60) and Span 60-Tween 65 used in the present study were particularly effective. Surprisingly, it was found that some combinations of emulsifiers accelerate the transition of form IV into form V. Transition of form V into form VI occurs via the solid state, and other transitions are known to take place via the liquid phase. Emulsifier was found to increase liquid fraction of the fat prior to its transition. Mechanistic considerations concerning these transitions are suggested.  相似文献   

15.
A number of North American vegetable and animal fat shortenings, which had been analyzed previously for their physical and textural characteristics, were analyzed also for their chemical composition. The fatty acid and triglyceride composition of the solids were calculated by analyzing the composition of the original product and the liquid phase, and by determination of the solid fat content (SFC) of the fat. The solids were also isolated by isopropanol (IP) separation, and the high melting glycerides (HMG) by acetone crystallization at 15°C. There was not much difference in total saturates andtrans content between vegetable and animal fat shortenings. Changing formulations from soy-palm to soy-cottonseed does not change the total saturates plustrans content. The solids of the vegetable shortenings in the β form contained about 20% of 16:0, those in the β′ form 30% or more. The animal fat shortenings were mainly in the β form, their solids contained 30% or more of 16:0. C54 triglyceride content of the solids of β vegetable shortenings (calculated and IP-separated) was >45%, that of all animal fats was <25%. Solids of animal fat shortenings contain high levels of C52. The C54 triglycerides are β-tending and should be kept low in vegetable shortening. In the HMG the C54 should not exceed 30%. This can only be achieved by incorporation of a β′ hard fat, preferably palm hard fat. Animal fat, especially lard, crystallizes in the β form because the palmitic acid in the glyceride molecule is located in the 2-position, whereas those of vegetable fats are in the 1- and 3-position.  相似文献   

16.
Summary 1. Even light of very high intensity has no significant effect on the peroxide development of “white” all-hydrogenated vegetable shortenings. Strong light, however, does cause a flavor and odor change which is not characteristic of rancid fat. 2. When determining the effect of light on shortenings in the laboratory, it is essential that the artificial light source have very nearly the same energy distribution characteristics as solar light, at least down to 325 millimicrons. 3. Light between 325 and 500 millimicrons is more effective in promoting an odor and flavor change in “white” shortenings than longer wave lengths. 4. Certain amber colored glass jars almost completely nullify the influence of light on the flavor and odor. Green and blue colored jars are helpful, but much less so than amber jars. Although appearing substantially opaque, opal glass jars are of little value in minimizing the effect of light. 5. Even strong light modifies the absorption properties of liquid “white” shortening very little in the ultraviolet and visible ranges. 6. Air-blowing liquid “white” shortening at an elevated temperature causes the absorption to increase perceptibly in the blue end of the visible range, but has no significant influence on the absorption in the ultraviolet portion.  相似文献   

17.
助乳化剂对化妆品乳液稳定性和液晶性的影响   总被引:6,自引:3,他引:6  
以硬脂酸蔗糖酯和失水山梨醇硬脂酸酯的复配物(SSE)为主乳化剂,十六/十八醇及甘油为助乳化剂制备含液晶乳液化妆品。通过观察乳液的温度稳定性和液晶性,用三元相图研究助乳化剂含量对此乳液体系液区的影响。实验条件下,用该乳化剂体系可获得较好的液晶化妆品乳液,总之,较高的助乳化剂量有利于乳液的温度稳定性和液晶性,但助乳化剂量较低时经合理配方也能获得稳定的液晶乳液,其中含3%高碳醇和5%甘油的乳液稳定性及液晶性均较好,5%高碳醇和3%甘油的助乳化剂体系不宜采用。  相似文献   

18.
Homopolymerisation of vinyl stearate and its copolymerisation with five other fatty vinyl monomers have been carried out in benzene using benzoyl peroxide as the initiator. The comonomers included stearyl acrylate, stearyl methacrylate, allyl stearate, stearyl vinyl ether and divinyl sebacate. Stearyl acrylate and stearyl methacrylate furnished copolymers with inherent viscosities much higher than that of the vinyl stearate homopolymer while allyl stearate and stearyl vinyl ether gave copolymers with inherent viscosities much lower than that of the vinyl stearate homopolymer.  相似文献   

19.
Sugar-based surfactants, such as sorbitan esters, sucrose esters, alkyl polyglycosides, and fatty acid glucamides gain increasing attention due to advantages with regard to performance, health of consumers, and environmental compatibility compared to some standard products. Sorbitan esters are well established products, which are mainly used as leather and textile auxiliaries or as emulsifiers for food at a volume of approx. 20,000 t/a. Sucrose esters are relatively hydrophobic products. The actual market size is estimated to be < 4,000 t/a – the main application being emulsifiers for food and cosmetics. Their use is still limited. Alkyl polyglycosides and fatty acid glucamides represent a perfect amphiphilic structure with excellent surface activity as well as solubility due to highly selective syntheses. For alkyl polyglycosides industrial processes have been developed in the past couple of years and a total capacity of ca. 80,000 t/a has been established. They are mainly used for cosmetic, manual dishwashing, and detergent applications. Fatty acid glucamides to date are exclusively used by one company in liquid and powdered detergents. The estimated production capacity is approx. 40,000 t/a. Comparable in their performance profile as co-surfactants, both products differ in their raw material base: whereas in the case of the fatty acid glucamides methylamine is incorporated in the product, alkyl polyglycosides are completely based on renewable resources. This, combined with very good performance and mildness, could be one reason why alkyl polyglycosides are the most successful sugar-based surfactants nowadays. Research to develop derivatives on this basis is still ongoing.  相似文献   

20.
Low trans-Fat Spreads and Shortenings from a Catalyst-Switching Strategy   总被引:1,自引:0,他引:1  
Low trans fatty acid basestocks suitable for blending with liquid oils to make spreads and shortenings are prepared by using a two-step hydrogenation process. The first step uses a nickel catalyst to hydrogenate soybean, canola, high-oleic sunflower, and high-oleic safflower oils to a predetermined iodine value. At this point in the reaction, the second step commenced. Addition of a platinum catalyst at 80 °C and 73 psi hydrogen pressure allowed for hydrogenation to proceed to iodine values of 40–50. These products had 11–18% trans fatty acid content. These were then blended with soybean oil (5–50% basestock) to give products with bulk properties similar to commercial spreads and shortenings but with about one third the levels of trans fat. Names are necessary to report factually an available data: the USDA neither guarantees nor warrants the standard of the product, and the use of the name USDA implies no approval of the product to the exclusion of others that may also be suitable.  相似文献   

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