Stearyl monoglycendyl citrate as an emulsifier enhancer

Stearyl monoglyceridyl citrate, a fatty acid ester, is a semisolid compound with a slightly acidic flavor. In its liquid state it is completely miscible with vegetable and animal fats and oils. Although the compound exhibits surfactant activity and reduces interfacial tensions, its major function is emulsifier enhancement and emulsion stabilization when used in shortening systems along with accepted emulsifiers. Very acceptable liquid and plastic shortenings can be prepared through the addition of stearyl monoglyceridyl citrate and primary emulsifiers. Effective levels of stearyl monoglyceridyl citrate in shortenings enhance performance and permit use of lower levels of primary emulsifiers. Shelf-life stabilities, smoke points, plasticity, and compatibility with primary emulsifiers in finished shortenings are good. Additions to margarines and whip toppings and performance in baked goods, as well as food additives status, are discussed.     

Making homogeneous and fine droplet O/W emulsions using nonionic surfactants

In many emulsion systems, creaming occurs during the first stage of emulsion breakdown. To reduce the rate of creaming, emulsions having small and uniform droplets are desirable. In this work, types and HLB of nonionic surfactants, emulsification methods, and combinations of oils and nonionic surfactants were investigated in order to make stable and homogeneous emulsions. Emulsification was attained by dissolving the surfactants in the oil phases. The addition speed and volume of water to the oil phases were important factors affecting the emulsion droplet size. The change of the solute state in the process of emulsification was observed stage by stage, and the mechanism of emulsification was elucidated. Homogeneous emulsions were formed in the HLB region, showing liquid crystalline and gel phases in the emulsifying process. The addition speed of water to the oil phase was very important in forming the liquid crystalline and gel phases. Polyoxyethylene(n)sorbitan monostearate could emulsify three kinds of oils (hydrocarbon, fatty acid ester and triglyceride). Polyoxyethylene(n)alkyl ether could emulsify hydrocarbon and fatty acid ester. Polyoxyethylene(n)-monostearate could emulsify only hydrocarbon. Surfactants with proper HLB which were soluble in the oil phase and in the presence of a very small amount of water formed a stable emulsion. The solubility state of oil and surfactant was the key to making a fine emulsion.     

Emulgatoren aus Schlachttierfetten

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.     

Stability of Emulsions Containing Interesterified Fats Based on Mutton Tallow and Walnut Oil

In this work, modified fats were produced by enzymatic interesterification of mutton tallow with walnut oil. As a result of forcing the fat hydrolysis process by addition of water to the enzymatic preparation (11.5, 13.0, 14.5, 16.0 wt %), additional levels of polar fractions (MAGs, DAGs, and FFAs) were observed. The aim of this work was to evaluate the stability of emulsions of modified fats containing natural emulsifiers resulting from enzymatic interesterification of mutton tallow with walnut oil. The physical‐chemical parameters of obtained fats were determined in this study. Using several methods, the stability of the formed emulsions was also evaluated. The results showed that the fats resulting from interesterification in the presence of Lipozyme RM IM (immobilized lipase from Rhizomucor miehei, Novozymes Bagsvaerd, Denmark) with 13.0, 14.5, and 16.0 wt % of water in the enzymatic preparation could form stable emulsion systems. On the other hand, the emulsion of the interesterification system where the amount of water in the enzymatic preparation was 11.5 % showed very low stability. The number of natural emulsifiers (MAGs and DAGs) that arose after interesterification was insufficient to stabilize the emulsion system. The work has shown the possibility of using interesterified fats as the fat phase. Emulsions formed on the basis of interesterified fats without any additional emulsifiers such as sunflower lecithin had properties comparable to emulsions containing mixed non‐interesterified fat containing additional emulsifier. The natural emulsifiers formed as part of enzymatic interesterification allow formation of stable emulsion systems.     

Emulsifier/oil system for reduced calorie cakes

Several emulsifiers were tested for their effects on the functionality of white layer cake batters in which plastic shortening was replaced with vegetable oil. The RV-1 emulsifier, a water dispersion of a mixture of sodium stearoyl lactylate, sorbitan monostearate and polysorbate 60 gave the best results when used in cake batters having the oil (corn oil or canola oil) content reduced as low as 6 or 3% (on flour basis) and sucrose (30%) replaced with either sorbitol or polydextrose. The cakes were comparable in quality with the plastic shortening control. To achieve this comparable quality, the emulsifier was used at 3% on flour basis and at a higher hydration than that of the control. Somewhat lower, but still acceptable, rating was received by cakes prepared with Atlas A. Propylene glycol mono fatty acid Esters (PGME, Atmul P 44 and RV) were found unsuitable for the tested system under the given conditions of formula and procedure.     

Effect of food emulsifiers on polymorphic transitions of cocoa butter

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.     

Functions of emulsifiers in food systems

The function of food grade emulsifiers in various food products (emulsions, starch based food, yeast raised bakery products, etc.) are reviewed. The stability of emulsions against coalescence of dispersed droplets is among other factors dependent on monoor multimolecular interfacial films with viscoelastic properties formed by adsorbed emulsifier molecules. Agglomeration of fat globules in whippable emulsion is needed to obtain desired foam stability and texture and can be controlled by lipophilic emulsifiers. Complex formation with starch components (amylose) is influenced both by the chemical structure of an emulsifier and by its physical behaviour in water. Interaction with proteins takes place primarily with anionic emulsifiers or very hydrophilic, nonionic types, which thereby improves the rheological properties of wheat gluten. Emulsifiers are also used as crystal modifying agents in fats where polymorphic changes during storage creates texture problems.     

Solidification and phase transformation behaviour of food fats — a review

Recent studies on physical behaviour of food fats have been reviewed, with an emphasis on solidification properties in bulk and emulsion states. It was shown that the use of synchrotron radiation X-ray beam highlighted the solidification behaviour of polymorphic fats, which was not unveiled by traditional X-ray beams on a laboratory scale as summarised in the following: (a) kinetic processes of molecular ordering of lamella-structured fat crystals, (b) mixing behaviour of different triacylglycerols forming miscible, eutectic, and molecular compound crystals, and (c) remarkable influences of shearing forces on the rapid solidification of the more stable forms of cocoa butter. These results have given some indications to the physical control of fat solidification, and the blending and fractionation of solid fats. The influences of hydrophobic emulsifiers on the solidification of fat crystals in O/W emulsions, which were in-situ monitored by an ultrasound velocity technique, have shown that the addition of highly hydrophobic emulsifiers having long-saturated acid moieties accelerated the nucleation of the fats at the interface areas of the emulsions. These effects are also indicative for the selection of the emulsifier for the control of the fat solidification in the emulsion phases.     

Characterization of Dispersion Systems Prepared with Mutton Tallow/Hemp Seed Oil-Based Diacylglycerols Using Ultrasonic or Mechanical Homogenization

The objective of this work was to compare the physical stability and physicochemical properties of emulsions, containing enzymatically modified fatty base and homogenized mechanically or by ultrasounds. In the study, lipase-catalyzed interesterification of mutton tallow and hemp seed oil, in a ratio of 3:1, 3:3, and 1:3 w/w, was performed in order to produce fatty bases of the emulsions. Reaction conditions were selected to obtain increased amount of the by-products (MAG and DAG), which were applied as the only emulsifiers in dispersion systems. The higher ratio of animal fat in the interesterified fatty basis of an emulsion had an impact on the greater stability of these systems. The correlation between thickening agent concentration in the prepared emulsions and stability was not observed. Smaller particle size was found in emulsions manufactured by ultrasonic homogenization, although it did not contribute to greater long-term stability of these emulsions. It was concluded that emulsions containing enzymatically modified fats and homogenized mechanically revealed greater physical stability than their counterparts homogenized with ultrasounds.     

Structure of the human milk fat globule

Milk is a sophisticated oil‐in‐water emulsion in which triacylglycerols, the single largest component of the infant's energy supply, are enclosed by an unusual trimolecular layer of polar lipids, proteins and cholesterol. Recently, interest has turned to the possibility that not just the membrane components and triacylglycerol fatty acids, but also their unusual structures may be particular features that enable delivery of intact bioactive molecules to the intestine, while facilitating efficient absorption and processing of milk fats, without metabolic stress. These features mean that the functional properties of milk fats are not replicated by mixtures of vegetable oils and emulsifiers and may be lost by processing. However, they offer opportunities for use of milk fat globule membranes and triacylglycerols structured to resemble milk fats.     

Emulsification for castor biomass oil

The effect of the emulsifier formula on the stability of castor oil-water system was studied through compounding three groups of emulsifiers from the aspects of stability factor of absorbance, centrifuge stability, demulsification time in quiescence, appearance of the droplets, and viscosity. The best emulsifier formula for castor biomass oil was the composite formula of sorbitan monooleate and polyoxyethylene sorbitan monostearate. Correlation exists between the stability of emulsion and the viscosity/particle size of the droplets, with better stability in the case of greater viscosity or narrower distribution of particle size in the emulsion of castor oil-water system. Methanol added to the castor oil-water system may decrease the viscosity of the emulsion. Comparing the castor oil-water emulsion with methanol-castor oil-water emulsion, the optimal hydrophilic and lipophilic balance (HLB) value based on castor oil-water system was acquired between 6.6 and 7.5, while the optimal HLB value based on the methanol-castor oil-water system was between 5.5 and 6.0. The optimal HLB value of methanol-castor oil-water system gradually moved to that of castor oil-water emulsion with adding more water.     

Pickering乳化剂在化妆品中的应用

综述了固体颗粒乳化剂的基本作用原理，主要内容包括固体颗粒乳化剂与传统表面活性剂乳化剂乳化性能的不同，固体颗粒乳化剂的作用机理及影响因素，以及固体颗粒乳化剂在化妆品中的应用前景。     

Effect of oil type on stability of high internal phase water-in-oil emulsions with super-cooled internal phase

This study considered the stability and rheology of a type of high internal phase water-in-oil emulsions (W/O) emulsion. The aqueous phase of the emulsions is a super-cooled inorganic salt solution. The oil phase is a mixture of industrial grade oils and stabilizer. Instability of these systems manifests as crystallization of the metastable dispersed droplets with time. This work focused on the effects of oil polarity and oil viscosity on the stability of these emulsions. Ten types of industrial oils, covering the viscosity range 1.4–53.2?cP, and with varying polarity, were used in combination with polymeric poly(isobutylene) succinic anhydride (PIBSA) and sorbitan monooleate (SMO)-based surfactants. The effect of oil relative polarity on rheological parameters of the emulsion was evident mainly in the emulsions stabilized using polymeric surfactant, whereas the oil viscosity did not show any significant effect. The optimum stability of the emulsions stabilized with SMO was achieved using high polar oils with a viscosity of 3?±?0.5?cP. However, when using the PIBSA surfactant, the best emulsion stability was achieved with low polar, high viscosity oils.     

Double emulsions of water-in-oil-in-water stabilized by α-form fat microcrystals. Part 1: Selection of emulsifiers and fat microcrystalline particles

Double emulsions are commonly stabilized by monomeric and/or polymeric emulsifiers. Pickering stabilization by solid particles such as colloidal microcrystalline cellulose has been mentioned only once as a possible technique to stabilize the external interface of the water-in-oil-in-water emulsion. No further work was carried out exploring this option. The present study shows that solid microcrystalline fat particles of α-form are capable of adsorbing at the water-oil interface and, together with other hydrophobic emulsifiers, can stabilize water-in-oil (W/O) emulsions. The crystals must be submicron in size in order to effectively adsorb and arrange at the interface. Large crystals do not fit and were found to flocculate as free crystals in the continuous oil phase. The α-form crystals can be obtained by flash-cooling saturated triglycerides in vegetable oils in the presence of emulsifiers, such as polyglycerol polyricinoleate (PGPR), that stabilize the dispersion and serve as α-tending crystal structure modifiers. It was assumed that PGPR also serves as a cross-linker or bridge between the crystalline fat particles and the water, and facilitates the anchoring of the fat particles in the oil phase in one direction while dangling itself in the water phase. The double emulsion droplets prepared with these W/O emulsions are relatively large in size (6–18 μm), but stable to coalescence. The marker (NaCl) does not seem to release with time, suggesting that the fat particles form microcapsules on the water interface, totally sealing the water from releasing its addenda. The systems seem to have a significant potential for food emulsions.     

Effect of food emulsifiers on crystal structure and habit of stearic acid

Several food emulsifiers have been found to serve as crystal structure modifiers for stearic acid crystallized from various organic solvents. Stearic acid that usually precipitates under appropriate crystallization conditions as the B- form is converted into the C- form when 1- 5% of sorbitan esters or ethoxylated sorbitan esters of fatty acids are present in the solution. Other emulsifiers such as polyglycerol esters, bdsubstituted monoglycerides and sucrose esters of fatty acids consisting of bulky hydrophilic groups are also effective emulsifiers in preserving the C- form of the crystallized stearic acid. The active emulsifiers modify the external crystal habit of stearic acid. Mass spectrograph analysis indicates that sorbitan monostearate (Span 60) is precipitated with the stearic acid.     

Emulsifiers derived from linseed oil and their potential use in coatings

In the development of a stable linseed oil emulsion paint, a series of emulsifiers were prepared from linseed, oil and its fatty acids and alcohols: (a) linseed monoglycerides, (b) mono-and dilinseed fatty sorbitan esters and a mixed ester obtained by the transesterification of linseed oil with sorbitol, (c) polyoxyethylene ether adducts formed by reacting, ethylene oxide with these sorbitan esters, and (d) linseed polyoxyethylene ether made by ethoxylation of linseed alcohols. Another series of surfactants was prepared by esterifying a polyoxyethylene ether of sorbitol with various amounts of linseed fatty acids. Conditions of preparation and pertinent physical, and chemical properties of the emulsifiers are given. Some of these emulsifiers demonstrated filmforming properties. Combinations were formulated into linseed oil emulsion paints with and without zinc oxide. Paints containing zinc oxide have been relatively stable in viscosity for about 2 yr.     

The antioxidant properties of gallic acid and allied compounds

Summary The differences between animal fats and common vegetable oils as regards their protection by antioxidants are briefly reviewed; in general, the former can be stabilized by di- and poly-phenolic inhibitors and by inhibitols, the latter by acid-type inhibitors such as tartaric, phosphoric and other acids; these acids reinforce the action of the inhibitols which occur naturally in vegetable oils or which may be added to animal fats. A study has been made of the antioxygenic action of the polyphenols on both kinds of fats. The trihydric phenols, gallic acid and ethyl gallate are effective stabilizers in animal and vegetable fats and enhance the antioxygenic activity of inhibitols; they thus demonstrate the properties of both phenolic and acid inhibitors. The possible mechanism of this synergistic action is briefly discussed.     

Argan oil-in-water emulsions: Preparation and stabilization

We prepared stable oil-in-water emulsions of argan oil with two different types of mixtures of nonionic emulsifiers. Three different types of oil (Israeli argan oil, Moroccan argan oil, and soybean oil) were emulsified with mixtures of Span 80 and Tween 80. The optimum HLB value for argon oil was 11.0 (±1.0). The argan oil-in-water emulsions were stable for more than 5 mon at 25°C. Synergistic effects were found in enhancing stability of emulsions prepared with sucrose monostearate. The origin of the oil and the internal content of natural emulsifiers, such as monoglycerides and phospholipids, have a profound influence on its interfacial properties and on the stability of the argan oil-in-water emulsions.     

Fate of dietary sterols in hydrogenated oils and fats

Samples of table margarines, so-called polyunsaturated table margarines, hydrogenated vegetable oils, and so-called polyunsaturated hydrogenated vegetable oils were shown by infrared spectroscopy to contain hydrogenated components. Examination of the sterols from these oils by argentation thin layer chromatography and gas liquid chromatography did not reveal campestanol, stigmastanol, or Δ²²-stigmastenol, the expected hydrogenation products of the natural sterols. The sterol compositions of the above samples, animal fats, and blends of hydrogenated vegetable oils and animal fats were determined. The compound 24-methyl cholest-7-en-3β-ol was identified tentatively in sunflower and safflower oils.     

不同可聚合乳化剂对丙烯酸酯乳液性能的影响

使用3种可聚合乳化剂制备了水基胶粘剂用丙烯酸酯乳液。考查了可聚合乳化剂与单体间的共聚性能,比较了各乳化剂用量对丙烯酸酯乳液的固含量和单体转化率、乳液稳定性(聚合稳定性、贮存稳定性、冻融稳定性)以及乳胶膜的耐水性等性能的影响。结果表明,乳化剂1-烯丙氧基-3-(4-壬基苯氧基)-2-丙醇聚氧乙烯(10)醚(ANPEO10)、烯丙氧基壬基酚聚氧乙烯(10)醚双磷酸(ANPEO10-P2)和烯丙氧基壬基酚聚氧乙烯(10)醚硫酸铵(DNS-86)均成功地聚合到丙烯酸酯聚合物中。用3种乳化剂制备的乳液性能各有特点。使用DNS-86以及ANPEO10-P2制得的乳液的贮存稳定性好;用ANPEO10制得乳液的冻融稳定性最好;使用DNS-86制得的乳胶膜的耐水性最好。3种乳化剂用量均为2.0%时,制得的乳液综合性能最好。