Quantitativer Nachweis von Milchfett in Schokoladenmischungen I: Bestimmung von Milchfettanteilen in Kakaobutter

Quantitative Detection of Milk Fat in Chocolate Mixtures I: Determination of Milk Fat in Cocoa Butter New methods for the quantitative determination of milk fat proportions in cocoa butter samples based on gas chromatographic analysis of fatty acids and triglycerides are described. 45 different cocoa butter types from 25 countries and 755 milk fat samples were analyzed by taking different feeding conditions into account. By means of triglyceride measurements mean relative deviations of approximately 5% from the 2–10% milk fat additions were established for known cocoa butter- and unknown milk fat composition. With completely unknown initial fats a mean relative deviation of approximately 6% was measured using fatty acid analysis.     

The determination of cocoa butter equivalents in chocolate

A method of determining cocoa butter equivalents in chocolate and cocoa butter is described. The method relies on a new approach for interpreting data obtained by triglyceride gas liquid chromatography (GLC). This technique provides information on the composition of a fat according to the carbon number of the triglycerides (C_n). Examination of the data for a wide range of cocoa butters shows that a straight line relationship between the C₅₀ and C₅₄ contents exists. This relationship has been used as the basis for a quantitative method determining the amount and type of cocoa butter equivalent added to chocolate. The application of the method to both plain and milk chocolate is described. The method is also used to determine the amount of milk fat in chocolate.     

Confectionery fats. II. Characterization of products prepared by interesterification and fractionation

Several cocoa butter-like fats, which had been prepared by fractional crystallization of the reaction product obtained on interesterifying highly-hydrogenated cottonseed oil and a triolein product or olive oil, were characterized and compared with cocoa butter. The fats, as obtained by fractional crystallization from acetone solutions, contained varying amounts of glycerides melting above 37°C., an undesirable feature which caused the fats to thicken too much when used in chocolate type compositions under the same conditions employed with cocoa butter. The higher-melting glycerides could be removed by filtration, or their proportions could be decreased by changing the fractionation temperatures. The fats melted mostly over the same temperature range associated with cocoa butter, and the best of the fats resembled cocoa butter closely over the temperature range 0° to 30°C. The cocoa butter-like fats resembled cocoa butter in hardness at all test temperatures. The fats were reasonably compatible with cocoa butter, that is, in mixtures of the two, one did not cause extensive premelting of the other. According to their cooling curves, the cocoa butter-like fats did not supercool as cocoa butter does. The former contain not only the 2-oleodisaturated glycerides of cocoa butter but also positional isomers of these glycerides. When the fats were molded under the same conditions employed with cocoa butter, linear shrinkage was only about one-third that of cocoa butter.     

Rapid densitometric determination of triglyceride groups by argentation thin layer chromatography

A method has been developed for the quantitative thin layer chromatographic determination of the triglyceride groups, differing in unsaturation, based on densitometry of the charred bands. Complete separation was achieved by continuous development in an open glass jar. The need for correction coefficients was avoided through addition of bromine to the double bonds prior to charring in the presence of sulphuryl chloride. The accuracy and precision of the method were evaluated on a standard mixture and on sunflower oil, olive oil, lard, cocoa butter, and beef tallow. The method is applicable for triglyceride group analysis of the most common fats and oils which contain saturated, monoene, and diene acids.     

Polymorphic changes in mixtures of confectionery fats

The polymorphic behavior of mixtures of cocoa butter and high melting cocoa butter fraction with three types of confectionery fats and mixtures of the confectionery fats with each other were investigated with a differential scanning calorimeter. The confectionery fats were an interesterified-fractionated fat, a hydrogenated-fractionated fat, and a lauric acid fat. The lowered melting point observed in mixtures of confectionery fats with cocoa butter or cocoa butter fraction was related to the proportion of triglycerides dissimilar to the major components in cocoa butter and cocoa butter fraction contained in a particular confectionery fat. The hydrogenated-fractionated fat contained ca. two-thirds 2-oleodisaturated triglycerides similar to the major components of cocoa butter; the interesterified-fractionated fat, ca. one-third 2-oleodisaturated triglycerides. The lauric acid fat contained virtually no triglycerides similar to cocoa butter. The series of mixtures of confectionery fats with cocoa butter and cocoa butter fraction that had the least melting point lowering were those that contained 25% hydrogenated-fractionated fat; the ones that had the greatest lowering of melting point were those that contained 25% lauric acid fat. Mixtures of confectionery fats with cocoa butter possessed considerable amounts of low melting components, whereas similar mixtures with cocoa butter fraction exhibited a narrower melting range and possessed few low melting components. The more highly crystalline confectionery fats can accommodate the addition of fats containing some low melting components. The most compatible of the series of mixtures of confectionery fats with each other was the mixture of interesterified-fractionated fat containing 25% hydrogenated fractionated fat; the least compatible, hydrogenated fractionated fat containing 25% lauric acid fat. Presented at the AOCS Meeting, Mexico City, April 1974.     

Effect of liquid fat on melting point and polymorphic behavior of cocoa butter and a cocoa butter fraction

The polymorphic behavior of cocoa butter and a high-melting fraction of cocoa butter (CBF) was investigated by differential scanning calorimetry. The effect of liquid fat on melting point and polymorphic behavior was established for six mixtures: 83.5% cocoa butter and 16.5% of a low-melting fraction of cocoa butter (CBF-LM), 90% cocoa butter and 10% olive oil, and four mixtures of CBF and olive oil containing 10%, 20%, 30%, and 50% olive oil. Six polymorphs were found for cocoa butter and at least five for CBF. The melting points for cocoa butter and CBF were 35 and 38 C, respectively. Addition of CBF-LM to cocoa butter reduced the observable polymorphs to four and the melting point to 32.5 C. In cocoa butter, 10% olive oil reduced the observable polymorphs to three and the melting point to 31.5C. Similarly, 10% olive oil in CBF reduced the observable polymorphs to three and the melting point to 37 C. Amounts of 20%, 30%, and 50% olive oil in CBF reduced the polymorphs to two and the final melting point to 34.5, 33, and 32 C, respectively. Possible explanations for the observed polymorphic behavior are advanced. Changes in the rates of tempering of cocoa butter and CBF on addition of various amounts of liquid fat are discussed.     

Phospholipid composition of lipid seed crystal isolates from ivory coast cocoa butter

Seed crystals isolated from Ivory Coast cocoa butter were shown to differ in chemical and thermal characteristics from solidified Ivory Coast butter. Higher concentrations of complex lipids in the seed crystals have led to speculation on the role these polar molecules play in lipid crystallization events. Phospholipids separated from lipid seed crystal isolates were twelve-fold more concentrated than the original cocoa butter. Seed crystals contained 3.99% phospholipids while cocoa butter samples contained 0.34%. Phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, lysophosphatidylcholine, phosphatidylserine, and phosphatidic acid were identified in cocoa butter with phosphatidylcholine (37.7%), phosphatidylglycerol (27.3%) and phosphatidyl-ethanolamine (15.6%) being the major phospholipid constituents. Two phospholipids not previously reported in cocoa butter were identified as phosphatidylglycerol and diphosphatidylglycerol based on co-migration of standards. Cocoa butter and its seed crystals contained the same phospholipid entities; however, individual phospholipids differed significantly in concentration. Phosphatidylethanolamine (30.4%) and phosphatidylcholine (30.2%) were the major phospholipids in seed crystal samples. Fatty acid composition of cocoa butter and seed crystal phospholipids were found to be similar, with the exception of myristic, stearic and oleic acids. Myristic acid was three-fold higher in phosphatidylglycerol and phosphatidylethanolamine in the seed crystals, whereas stearic acid was significantly lower in the seed crystals when compared to the cocoa butter. Concentrations of oleic acid were twice as high in seed crystal phosphatidylethanol-amine and almost four times as high in seed crystal phosphatidylcholine than in corresponding cocoa butter samples. The possible role phospholipids play in seed crystal development and in crystallization events is discussed.     

A Method to Qualify and Quantify the Crystalline State of Cocoa Butter in Industrial Chocolate

A range of methods, mainly X-Ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC), have been used to characterise the polymorphism of fats in food products. As sugars present in chocolate have a significant XRD pattern, partially overlapping with the signal of cocoa butter, XRD cannot be applied directly to chocolate. In this paper, the XRD signal of a molten sample, similar to the one for pure sucrose, was subtracted from the signal of a solid sample of chocolate to remove the impact of the crystallised sugar. The XRD patterns obtained were compared with the pattern of cocoa butter cooled under the same conditions. Strong peaks were observed at similar inter lamellar d spacings showing that the polymorphic state of cocoa butter in processed chocolate could be obtained using this method. Numerical integration of the peaks also allowed quantification of the degree of crystallinity present in the system during a typical process. The accuracy of the method developed was found to be dependent on the (cocoa butter)/(sugar) ratio in the chocolate used.     

Stereospecific analysis of the major triglyceride species in the monounsaturated fraction of cocoa butter

A stereospecific analysis employing pancreatic lipase,Geotrichum candidum lipase and phospholipase A was applied to the monounsaturated triglyceride fraction of cocoa butter. Diacid triglycerides required additional analyses involving the gas liquid chromatographic determination of the proportions of digly ceride acetates produced by separately acetylating the α,α and α,β-digly cerides obtained from aG. candidum digestion mixture. Results indicated that the major triacid triglyceride in cocoa butter wasrac glyceryl-l-palmitate-2-oleate-3-stearate. Approximately 5% of cocoa butter was comprised of triglycerides which were solely or predominantly of one enantiomer, containing oleic acid in the 3 position. Scientific contribution No. 348 Agricultural Experiment Station, University of Connecticut, Storrs.     

Cocoa butter-like fats from fractionated cottonseed oil: II. Properties

Previously it was reported that the stearine obtained as a byproduct in the solvent winterization of cottonseed oil is a good starting material for the preparation of cocoa butter-like fats by way of hydrogenation and fractionation. The composition, physical properties, and compatability with cocoa butter have been determined for some of these fats. While the products contained triglyceride species other than those in cocoa butter, the major components were similar in that they were 2-oleodisaturated glycerides. The cocoa butter-like fats underwent slow polymorphic transformations, but made confectionery coatings remarkably resistant to bloom. Cooling curves resembled those of cocoa butter. Hardness was related to melting point; those fats melting below 35 C were softer than cocoa butter at room temperature, but fats melting above 35 C could be made to resemble cocoa butter in hardness. Adding cocoa butter to the cocoa butter-like fats had little effect on the softening point. X-Ray diffraction studies of 1:1 mixtures gave no evidence of mixed crystal formation; the long spacings resembled those of mechanical mixtures. In some other mixtures, certain short spacings became more pronounced. ARS, USDA.     

Cocoa butter extenders from Kokum (Garcinia indica) and Phulwara (Madhuca butyracea) butter

Cocoa butter extenders, suitable for use in chocolate and confectionery, were prepared from Kokum fat and a Phulwara butter fraction. The latter fraction was prepared from Phulwara butter by two-stage dry fractionation and blended with Kokum fat in selected proportions to obtain a series of hard butters with different melting profiles. The blends with higher proportions of Kokum fat were harder and hence may find application in warm climates. The blends with higher proportions of Kokum fat were harder and hence may find application in warm climates. The blends had solidification properties, fatty acid and triacylglycerol compositions similar to those of cocoa butter. In addition, they had narrow melting ranges like cocoa butter, and they were compatible with cocoa butter and have tolerance toward milk fat.     

Confectionery fats from palm oil and lauric oil

In 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.     

Effect of 2-oleodipalmitin and 2-elaidodipalmitin on polymorphic behavior of cocoa butter

The polymorphic behavior of cocoa butter mixed with 2-oleodipalmitin (POP) or 2-elaidodipalmitin (PEP) was investigated with a differential scanning calorimeter. Six mixtures of cocoa butter containing 10, 25, and 50% POP and 10, 25, and 50% PEP were used. Each of the three cocoa butter-POP mixtures exhibited at least four polymorphic forms. The lowmelting form was obtained by quick chilling; the intermediate, by tempering for several hours just below the melting range; and the high-melting, by raising the temperature slowly to 25 C then holding there overnight or longer. In the cocoa butter-POP mixtures, only the low-melting form appeared to be more stable than the corresponding form for pure POP or cocoa butter. In addition to increased stability of the unstable low form, the rate of conversion from the intermediate to the high form, normally quite slow, increased in the cocoa butter-POP mixtures. Typical melting point lowering occurred when POP was added. POP was quite compatible with cocoa butter, the tempered mixture melting as a single compound; and the melting curves were fairly sharp. The three cocoa butter-PEP mixtures appeared to be incompatible. The cocoa butter and PEP behaved like a mixture of two fats, each of which melted independently. Presented at the AOCS Meeting, Chicago, Sept. 1973.     

Rapid MS method for analysis of cocoa butter TAG

Ammonia negative ion CI-MS was applied to analyze the M.W. distribution and regioisomeric structure of TAG in cocoa butter and in cocoa butter equivalents. The M.W. distribution results obtained for a reference cocoa butter were consistent with corresponding results obtained in an intercomparison study by chromatographic methods. Minor but statistically significant differences were observed when proportions of the three major M.W. species (52∶1, 54∶1, and 50∶1; acyl carbon number/number of double bonds) in a mixture of nine cocoa butters and in mixtures containing 10 or 20% (w/w) of specific cocoa butter equivalents were compared. Tandem MS was used to determine the regioisomeric structure of the three major TAG M.W. species in cocoa butter and in cocoa butter equivalents. The regioisomeric structure in cocoa butter and in all the equivalents analyzed were nearly identical, oleic acid being located primarily in the sn-2 position. These results cannot be exploited in detecting added foreign fats in this case. However, the present study shows that useful TAG composition data, which may be used to detect foreign fats in cocoa butter by applying chemometric data evaluation, can be obtained by MS in a significantly shorter time compared to chromatographic methods.     

Analytical platforms to assess the authenticity of cocoa butter

This paper reviews strategies to detect and analyse cocoa butter equivalents added to genuine cocoa butter or to chocolate products. The legal background of the issue is that current European legislation allows the addition of vegetable fats other than cocoa butter to chocolate up to a level of 5% of the product weight, provided that the addition is correctly indicated on the label. However, the Directive fails to specify a method of analysis to enforce compliance. The principal themes highlight compositional data (triglyceride and fatty acid composition, components of the unsaponifiable matter) of cocoa butter from different origins and suitable raw materials used for the formulation of cocoa butter equivalents, and explains how analytical techniques (gas‐liquid chromatography, high‐performance liquid chromatography, infrared spectroscopy, pyrolysis mass spectrometry) make use of subtle differences between the two commodities to detect commingling.     

Characterizing cocoa butter seed crystals by the oil-in-water emulsion crystallization method

Unambiguous quantitative evidence for the catalytic action of seed crystals in cocoa butter is presented. We used an ultrasound velocity technique to determine the isothermal growth of solid fat content in cocoa butter oil-in-water emulsions, in which the probability of finding a seed crystal in any one droplet was around 0.37 at 14.2°C. The upper limit for the size of seed crystals in West African cocoa butter was around 0.09 μm, the Gibbs free energy for nucleation was 0.11 mj m⁻², and the concentration of seed crystals was in the range of 10¹⁶ to 10¹⁷ m⁻³. X-ray diffraction measurements showed that emulsified cocoa butter crystallizes in the α polymorph and does not appear to transform to the β′ form within the first 25 min of crystallization. Primary nucleation events in cocoa butter emulsions are accounted for by seed crystals. Collision-mediated nucleation, a secondary nucleation mechanism, in which solid droplets (containing seed crystals) catalyze nucleation in liquid droplets, is shown to account for subsequent crystallization. This secondary nucleation mechanism is enhanced by stirring.     

Characterization of cocoa butter extracted from hybrid cultivars of Theobroma cacao L

Cocoa butter is the most important fat used in the confectionery and chocolate industries. The main objective of the present study was to determine the physical and chemical characteristics of cocoa butter extracted from hybrid cultivars belonging to the germplasm bank of the Fondo Nacional de Investigaciones Agropecuarias (National Foundation for Agricultural Research). AOAC methods were used for the assessment of the proximal composition of the beans, physical and chemical characteristics as well as for the fatty acid profile of the fat. It was found that there were statistical differences in the proximate composition of the cocoa beans among the cultivars studied as well as the iodine and saponification indices of the butter. Saturated fatty acids were present in higher proportions than unsaturated fatty acids, with palmitic and stearic acid as the main fractions. Oleic acid content was higher than linoleic acid. The fatty acid profile found is the main factor that influences the hard texture of the cocoa butter from Venezuelan cocoa hybrids cultivars.     

Solidification of cocoa butter

Cocoa butter and other confectionery fats do not behave alike on molding. Explanations for the behavior of cocoa butter generally are unavailable. The linear contraction of molded cocoa butter on solidification under various conditions was determined. Maximum linear contraction of about 2% was measured when a well-seeded sample was solidified at 16C. Nearly all of this contraction occurred during the first half hour. A theoretical explanation for this contraction was developed. Linear contraction takes place after the well-seeded cocoa butter has solidified in the next-to-highest melting form and while this solid form is transforming to the most stable polymorph. Addition information was developed on the polymorphic forms of cocoa butter, the permanence of seed crystals at various temps, rates of solidification, and solidification characteristics of unseeded cocoa butter. The data were obtained by dilatometric examination of a small sample using a volumetric dilatometer and direct measurement of linear contraction during solidification in a mold. Presented at the AOCS Meeting in Atlanta, April, 1963.     

Cocoa butter substitutes from mango fat

Mango fat obtained by solvent extraction of the kernels of the mango fruit (Magnifera indica) has been studied for its suitability in making cocoa butter substitutes. The fat has been fractioned from acetone at low temperatures in one and/or two stages in order to segregate suitable solid fractions having physical properties closer to cocoa butter. The data pertaining to the solidification characteristics and dilatometric behavior of the mango fat, its acetone-fractionated products and their admixtures with cocoa butter in equal proportions have been determined in order to assess their compatibility with cocoa butter. Fractionated mango fat can serve as a good partial substitute for cocoa butter.     

Phase behavior and extended phase scheme of static cocoa butter investigated with real-time X-ray powder diffraction

A complete isothermal phase-transition scheme of cocoa butter under static conditions is presented, based on time-resolved X-ray powder diffraction experiments. In contrast to what is known from literature, not only β V, but also β VI can be obtained directly through transformation from β′. Another remarkable result is that β′ exists as a phase range rather than as two separate phases. Within this β′ phase range no isothermal phase transitions have been observed. More detailed information concerning the observed cocoa butter polymorphs was obtained by determination of melting ranges, using time-resolved X-ray powder diffraction. Also standard X-ray powder diffraction patterns of the γ, the α, and the two β phases and parts of the β′ phase range have been recorded. The observed phase behavior of cocoa butter has been explained based on the concept of individual crystallite phase behavior of cocoa butter