Confectionery Fats Research Articles

Physical and chemical properties of trans‐free fats produced by chemical interesterification of vegetable oil blends

AbstractFat blends, formulated by mixing a highly saturated fat (palm stearin or fully hydrogenated soybean oil) with a native vegetable oil (soybean oil) in different ratios from 10:90 to 75:25 (wt%), were subjected to chemical interesterification reactions on laboratory scale (0.2% sodium methoxide catalyst, time=90 min, temperature=90°C). Starting and interesterified blends were investigated for triglyceride composition, solid fat content, free fatty acid content, and trans fatty acid (TFA) levels. Obtained values were compared to those of low‐ and high‐trans commercial food fats. The interesterified blends with 30–50% of hard stock had plasticity curves in the range of commercial shortenings and stick‐type margarines, while interesterified blends with 20% hard stock were suitable for use in soft tubtype margarines. Confectionery fat basestocks could be prepared from interesterified fat blends with 40% palm stearin or 25% fully hydrogenated soybean oil. TFA levels of interesterified blends were low (0.1%) compared to 1.3–12.1% in commercial food fats.

Separation of molecular species ofcis‐ andtrans‐triacylglycerols intrans‐hardened confectionery fats by silver‐ion high‐performance liquid chromatography

AbstractSilver‐phase high‐performance liquid chromatography (HPLC) on silver nitrate‐loaded silica achieves incomplete separation of major triacylglycerol (TAG) classes present intrans‐hardened fats. The “ChromSpher Lipids” silverloaded cation exchange HPLC column has been found to yield good separations oftrans‐hardened TAG, with molecular species well resolved. Separations comparable to those previously possible for nonhardened fats are now possible fortrans‐hardened fats. The separation is on the basis of number and type (i.e.cis/trans) of double bonds only; the position of the double bond along the acyl group appears not to influence the separation significantly. The analysis of a palm fraction, hardened to a slip melting point of 37°C and chemically randomized, is presented as an example. This technique offers a new approach to understanding and controlling the hydrogenation and processing oftrans‐hardened fats.

Melting and solidification characteristics of confectionery fats: Anhydrous milk fat, cocoa butter and palm kernel stearin blends

AbstractDifferential scanning calorimetry measurements of crystallization and melting characteristics of commercial samples of anhydrous milk fat (AMF), cocoa butter (CB) and hydrogenated palm kernel stearin (PKS) in ternary blends were studied. Results showed that stabilization at 26°C (either for 40 h or 7 d) did not greatly affect the melting thermogram trace of PKS. However, the effect of stabilization became prominent as CB was added into the system. Deviation of measured enthalpy from the corresponding values, calculated for thermodynamically ideal blends, showed clear interaction between all three fats. At 20°C, the strongest deviation occurred at about the AMF/CB/PKS (1∶1∶1) blend, whereas at 30°C the deviation moved toward the CB/MF (1∶1) blend. The presence of 25% AMF in PKS had little effect on its solidification capability, but solidification was adversely affected with inclusion of CB.

Confectionery Fat from Phulwara (Madhuca butyracea) Butter

AbstractPhulwara butter behaved like a plastic fat without showing any supercooling property, which is mainly due t o presence of trisaturated triacylglycerols. The olein obtained after removal of about 10% harder stearin fraction showed considerable improvement in supercooling property. However, the olein had lower solids content at ambient temperatures, which make it unsuitable for use in chocolate and confectionery. On the other hand, the middle stearin fraction obtained by two‐stage fractionation had sufficient solids content at these temperatures. The middle fraction, when mixed with cocoa butter, depressed the overall melting range of the latter by lowering the solids content at 32.5°C, the effect being more pronounced as the level of the fraction in the mixture increased. At 15% concentration with cocoa butter, the fraction had cooling curve similar to that of cocoa butter. The fraction was found t o have slightly better tolerance towards milk fat compared to that of cocoa butter. The results revealed that the fraction when incorporated into chocolate along with cocoa butter, imparted more cooling sensation in the mouth compared to those prepared with cocoa butter alone. The fraction was found to be suitable to replace part of cocoa butter in chocolate and other confectionery products, where cooling sensation is desirable and finds application in cold climates and also in the preparation of ice‐cream coatings.

Differential scanning calorimetry of confectionery fats: Part II—Effects of blends and minor components

Differential scanning calorimetry (DSC) measurements of the crystallization and melting phenomena of typical confectionery fats are presented. The results show the sensitivity and reproducibility with which DSC data can be used to classify the types of confectionery fat. Calculations of the reproducibility of crystallization and melting parameters obtained from DSC are presented. In addition, the effects are shown on the thermograms of progressive changes in formulation to a typical cocoa butter equivalent. Further, the effects brought on by the presence of minor components, such as trisaturated triglycerides and other polar materials, which are common in confectionery fats, are described and quantified.

Differential scanning calorimetry of confectionery fats. Pure triglycerides: Effects of cooling and heating rate variation

AbstractDifferential scanning calorimetry (DSC) measurements of the crystallization and melting phenomena of pure forms of the three principal triglycerides present in cocoa butter and related confectionery fats are presented. The results are used to exhibit the usefulness of the DSC technique for potential application in quality control of these types of material, but also as a warning of the difficulties in interpretation of data. The results also serve as a reference for future use in DSC studies of similar materials.

Confectionery fats from sal ( Shorea robusta) fat and phulwara ( Madhuca butyracea) butter

Stearins from sal fat and phulwara butter were blended in selected proportions to obtain confectionery fats or cocoa butter extenders. The sal fat stearin was obtained by removing about 20% olein from sal fat by acetone fractionation at 15°C, and the phulwara butter stearin was obtained by two-stage acetone fractionation. In the first stage of phulwara butter fractionation, a small amount of stearin (equal to 10% by weight of butter) was removed from the phulwara butter. The resulting olein was further fractionated at 15°C to obtain stearin (yield 65% by weight of olein). The blends containing 75–85% of sal fat stearin and 15–25% of phulwara butter stearin had solidification properties and solid fat indices close to those of cocoa butter. These blends could be used as cocoa butter extenders. Cocoa butter extenders which impart a greater cooling sensation in the mouth were prepared by decreasing the proportion of sal fat stearin to 50–67% in the blend. The blends containing 50:50, 67:33, 75:25 and 85:15% of sal fat: phulwara butter stearins were compatible with cocoa butter when admixed even at equal proportions. The tolerances of the blends towards milk fat were similar to that of cocoa butter. Thus, a series of cocoa butter extenders or confectionery fats, having a narrow melting range and melting profiles similar to those of cocoa butter could be prepared by altering the proportion of sal fat and phulwara butter stearins in the blends.

PHYSICAL-CHEMICAL BEHAVIOR OF CONFECTIONERY FATS

Abstract Confectionery coatings employ hard butter fat systems made from both lauric and non-lauric source oils. These oils are routinely modified by a combination of treatments including hydrogenation, fractionation and interesterification to achieve desired physical properties. Such processing methods create heterogeneous triglyceride mixtures consisting of a variety of compositional and positional isomers. Published phase diagrams of “simple” binary triglyceride mixtures of closely related molecules are complex, and suggest that innumberable unique liquid and solid phases may co-exist at any given temperature ( and pressure ) in vastly more complex triglyceride mixtures such as confectionery hard butters. Thus we may view confectionery fat systems as multiphasic mixtures (liquid, solid and compositional) with a propensity to undergo liquid content fluctuations and crystal size/morphology changes in response to slight changes in temperature. A true equilibrium among all phases may indeed never be attained, and a potential for movement of certain components in response to temperature change is probably constant. Surface growth of long needle-like fat crystals, “fat bloom”, most likely results from this non-equilibrium condition and serves to reduce the system's free energy. The ever present, ever changing liquid phase(s) is viewed as the vehicle for free energy minimization via triglyceride migration and ongoing crystal growth.

Polymorphism of 1, 3-Di (saturated acyl) -2-oleoylglycerols : POP, SOS, AOA and BOB

Polymorphic behavior was studied for series of 1, 3-di (saturated acyl) -2-oleoylglycerols in which the saturated acyl groups were palmitoyl (POP), stearoyl (SOS), arachidoyl (AOA) and behenoyl (BOB). The purity of the samples employed was 90.4% (POP), 91.3% (SOS) 83.2% (AOA), and 71.5% (BOB). Attention was directed to the identification of an independent polymorph by subjecting the sample to two thermal treatments : transformation in a crystalline state at different temperatures after chilling the melt at 0°C, and solidification of more stable polymorphs after rapidly melting the less stable forms. The long and short spacing spectra, examined by X-ray diffractometry and the melting point were used to determine the polymorph.Five independent polymorphs were found to occur frequently in the four triacylglycerols examined : α, γ, pseudo-β', β2 and β1 at ambient temperatures. The melting points increased in the order described above, being α the lowest and β1, the highest. In addition, sub α appeared in SOS, AOA and BOB as a less stable form than α, where as β' was observed in POP, AOA and BOB with stability intermediate between α and γ. All the above polymorphs exhibited distinctively different short spacing spectra and melting points. The solid-state transformation occurred in a sequential way from (sub α) α to β1, implying the nature of the polymorphism to be monotropic. The chain length structure was a double chain for α and β' of the four triglycerides examined, and for pseudo-β', singly of POP. Triple chain length structure was found for γ, β2 and β1 in all the glycerides and pseudo-β' in SOS, AOA and BOB. Although rather complicated, the present findings showed good agreement with data in previous reports which have long been contradictory to each other. Taking the X-ray data and previous reports into account, the new nomenclature of the polymorphs discussed above was explained. Finally, the authors consider that the V-VI transformation of cocoa butter, responsible for the blooming phenomena of confectionery fats, may possibly be caused by polymorphic transformation from β2 to β1 of the solid fat fractions of cocoa butter.

Processing of Palm Kernel Oil

AbstractBy the end of the century palm kernel (PK) oil is forecast to rank fifth in volume of world trade in oils, only slightly behind coconut oil. PK oil received by Malaysian refiners is of good quality, typically below 2% in free fatty acids, and is easily refined. PK oil is fractionated to give a higher melting fraction (stearin) and a lower melting fraction (olein). The various processes used are described. PK oil, olein or stearin are also hydrogenated to give a range of products ranging in melting point from about 24 to 44°C. PK oil and olein are interesterified alone or in blends with a non‐lauric oil to give products with improved melting properties and utility. The utilisation of PK oil in the main application areas of confectionery fats, non‐dairy/imitation dairy products, biscuit creams, industrial margarines, nut roasting and spray oils are discussed.

The Use Of Hplc To Separate Triglycerides In Confectionery Fats Using Ultra Violet Detection

Abstract The triglycerides of confectionery fats have been separated by reverse phase HPLC using mixtures of either acetonitrile and tetrahydrofuran or acetonitrile and methyl tertiary butyl ether using UV detection at 237 nanometres. The method has been applied to samples of cocoa butter, cocoa butter equivalents, milk fat and other vegetable fats. The fat from a milk chocolate has been separated by the above system.

Confectionery fats from palm oil

AbstractThe influence of diglycerides (DG's) and trisaturated glycerides (P‐P‐P) on tempering and the hardness of confectionery products are described. Palm oil and its processed products in confectionery fats have been reported (1,2). Palm oil contains a symmetric triglyceride (P‐O‐P) as a main component which has polymorphic changes similar to those of cocoa butter, so a mixture of these is able to use a tempering process similar to that used for cocoa butter.Details for fat crystals and polymorphism have been reported (3,4). Okada (5) used a mixture of tristearin and tripalmitin and studied the behavior of polymorphism using X‐ray diffraction. The effects of DG's on polymorphic change in palm oil also have been reported (6,7), and Okiy (8) suggested that DG's have an inferior effect on the quality of palm oil when used in the solidified phase. However, there have not been many papers regarding how the above influence works in the production process or how it affects confectionery products.Palm oil contains about 10% trisaturated glycerides together with a few percent of mono‐ and diglycerides as minor components, which have been produced during the maturation of palm fruits and processing of fats. It is very difficult to eliminate these completely during the refining process.This paper reports a study of the influence of these minor components on tempering and hardness of products by using a simulated tempering machine. We have found that DG's lower the temperature of tempering and soften the hardness of products and that P‐P‐P increased the viscosity of products during tempering process but increased the hardness of products very little.

Confectionery fats from palm oil and lauric oil

AbstractIn the search for economical cocoa butter alternatives, palm and lauric oils have emerged as important source oils in the development of hard butters. Based on the method presented for categorizing hard butters, the lauric oils, primarily palm kernel and coconut, can be modified by interesterification and hydrogenated to yield lauric cocoa butter substitutes (CBS) which are both good eating and inexpensive. Fractionation, although adding to the cost of production, can provide lauric hard butter with eating qualities virtually identical to cocoa butter. Unfortunately, one factor identified with the lauric oils is their very low tolerance for cocoa butter.Palm oil, on the other hand, has been identified as a valuable component in all types of cocoa butter alternatives. It is a source of symmetrical triglycerides vital in the formulation of a cocoa butter equivalent (CBE). It can be hydrogenated or hydrogenated and fractionated to yield hard butters with a limited degree of compatibility with cocoa butter, allowing some chocolate liquor to be included in a coating for flavor enhancement. Palm oil is used with lauric oils as a minor component in interesterified lauric hard butters, as well as functioning as a crystal promoter in coatings formulated with a fractionated lauric CBS. While palm oil's importance and flexibility have been duly noted, some important concerns remain from a market perspective. The fact that the CBE fats are very expensive suggests they offer limited cost savings compared to cocoa butter. The potential for CBE products is still questionable in those countries where chocolate labeling standards preclude the use of vegetable fats other than cocoa butter. The nonlauric CBS products, while cheaper than the CBE types and able to tolerate limited levels of cocoa butter, do not exhibit the level of eating quality characteristics present in the lauric hard butters.Some challenges remain for today's oil chemists. An economical nonlauric CBS, made predominantly from palm oil, possessing the eating quality of a fractionated lauric CBS and exhibiting good compatibility with cocoa butter would be met with considerable interest by the chocolate and confectionery industries. As for the lauric oils, it would seem reasonable to assume that greater cocoa butter compatibility, if attainable, could enhance their potential for gaining even greater acceptance by confectionery manufacturers currently using pure chocolate. As for the CBE products, the major issue is cost. If the cost of a CBE could be reduced to a level which would allow a CBE to compete with the nonlauric and lauric cocoa butter substitutes, a major advancement in the evolution of cocoa butter alternative fats will have been achieved.

Fractionation of lauric oils

AbstractThe different methods of edible oil fractionation are reviewed, and the applicability of these to the fractionation of palm kernel and coconut oils is discussed. Crystallization from solvents such as acetone, hexane or 2‐nitro‐propane, is the most easily understood and most convenient for small‐scale laboratory trials, but the cost of solvents and the need to flameproof plants makes it uneconomical for an industrial undertaking. Dry crystallization is commonly employed, and there are several methods, described here, for subsequent separation of solid stearin from liquid olein. Chemical and physical properties of the separated stearins and oleins depend on fractionation conditions and on the yields sought. These are reviewed. The properties of the fractions may be further modified by hydrogenation, interesterification, blending or combinations of these techniques.Many sophisticated confectionery fats are manufactured from lauric stearins and their methods of manufacture and product applications are reviewed. A commercial operation must take care to find a good outlet for the secondary fractionation products (or byproducts) however, and useful outlets for these secondary fractions are therefore considered in addition to those of the main product.

Confectionery fat analysis with high performance liquid chromatography

AbstractNatural triglyceride mixtures have been analyzed by a variety of techniques. Earlier methods, such as crystallization, were unsuitable because they were very time‐consuming, required large amounts of material and were not reproducible. Later advances in chromatography gave successful separations of triglycerides but required a combination of techniques to give suitable separations. High performance liquid chromatography (HPLC) with very efficient columns has been successfully applied to triglyceride separations on a routine basis. In the present work, triglycerides of cocoa butter as well as several replacement fats were separated by HPLC. The system consisted of a highly efficient column packed with octadecylbonded spherical silica (5 µ) and a mobile phase composed of acetone and acetonitrile. Peaks corresponding to eluted components were collected and their composition determined by gas chromatography (GC) of the corresponding methyl esters to allow unambiguous assignment of triglyceride structure to the components. A profile of the triglycerides present in such fats can be obtained within 30 min.

Modification of Some Tree Borne Seed Fats for the Preparation of High Priced Confectionery Fats

AbstractSal(Shorea robusta), mango kernel(Mangifera indica), and mowrah (Madhuca latifolia) are three major tree borne seed fats and regarded as potential cocoabutter substitute when suitably modified. Modification of these fats by fractionation from solvent and blending of the fractions among themselves and with other suitable fatty material yielded a series of high priced confectionery fats.

Development of a continuous process to obtain a confectionery fat from tallow: Final status

AbstractA two‐step pilot plant continuous process fractionally crystallized edible beef tallow into three fractions‐a confectionery fat (14%), cooking oil (69%), and stearine (17%). The tallow was dissolved in acetone to a concentration of 11.6% by weight. The use of scraped surface heat exchangers with high external recycle permitted crystallizations at 60–65 F and 40–42 F, respectively, with only 5 min nominal dwell times in each crystallizer. A cost estimate indicated that the process to separate continuously a confectionery fat from tallow may be commercially feasible, dependent upon the price and market of the other two fractions.

Factors Influencing the Use of Vegetable Fats in Chocolate

AbstractThe phase behaviour of binary mixtures of cocoa butter with three types of confectionery fat are described. The information allows us to predict the levels at which different types of fat can be mixed with cocoa butter to provide satisfactory chocolate products.

Hard butters and confectionery coatings

AbstractThe art on confectionery coatings and hard butters is reviewed showing the evolution and acceptability of such products over the years. The various types of hard butters are identified, and their application in confectionery coatings is indicated. The practices and the areas of application for the different products are discussed as well as the raw materials used to produce the confectionery fats. Raw material cost of chocolate and hard butters is projected over the years to demonstrate the advantages of hard butters for confectionery coatings.

A Method for the Determination of the Solid Phase Content of Fats Using Pulse Nuclear Magnetic Resonance

AbstractUntil quite recently dilatation measurements were frequently used to provide information related to the solid phase content of commercial shortenings and margarine fats. With the appearance of reliable and relatively inexpensive pulsed magnetic resonance spectrometers it has become possible to replace the tedious and laborious dilatation technique by one using pulse nuclear magnetic resonance. This method has been shown to have considerable advantages over the continuous wave nuclear magnetic resonance technique for solids content determination in fats favoured by some workers and has now found extensive application within Unilever. A review of the basic method employed within Unilever for solids content determination in margarine fats is given and is discussed in the light of more than five years of experience of the use of the method within the Unilever margarine business. The extension of the above method for solids content determination in margarine fats to enable the measurement of solids content in confectionery fats is also described.