Portable Infrared Spectrometer to Characterize and Differentiate Between Organic and Conventional Bovine Butter

The performance of a portable infrared system combined with pattern recognition to discriminate between organically and conventionally produced bovine butter samples as well as to predict the levels of conjugated linoleic acid (CLA) were evaluated. Sixty butter (27 organic and 33 conventional) samples were used in this study. Bovine butter–fat were applied onto an attenuated total reflectance infrared (ATR‐IR) accessory equipped with a five‐bounce ZnSe crystal set at 65 °C for spectral collection. In addition, ATR‐IR spectra of bovine butter were directly collected at room temperature to avoid phase separation. The fatty acid profile and the levels of CLA were determined using reference FAME‐GC‐FID analysis. SIMCA models showed well separated clusters that discriminated between organic and conventional bovine butters due to C=C trans bending out of the plane vibration modes band at 967 cm^?1. Additionally, strong PLSR models were developed to predict CLA levels using butter–fat and bovine butter spectra with SEP of 0.05 % and RPD of 4.7, indicating that the models are suitable for quality control applications. Portable IR technology offers the ability for “in situ” analysis of butters that is much less time consuming than current analytical practices for authentication and quality control efforts by the industry.     

Effect of temperature on recrystallization behavior of cocoa butter

Crystallization of cocoa butter in the β phase directly from the melt is only possible by employing the memory effect of cocoa butter. Cocoa butter crystallized in the β phase, heated to the so-called maximal temperature (just above its melting end point), recrystallizes in the β phase after cooling to a crystallization temperature. The influence of the maximal and crystallization temperatures on the recrystallization behavior has been investigated for two cocoa butters. Rapid-starting recrystallization into the β(VI) phase and slow-starting recrystallization into the β(V) have been observed. It is concluded that rapid-starting recrystallization is induced by high-melting 1,3-distearoyl-2-oleoyl-glycerol (SOS)-rich crystals. The two β phases were identified by X-ray powder diffraction and melting ranges. However, the X-ray powder diffraction patterns for the β phases depended on the composition of the cocoa butter and on the crystallization method used. Therefore, it was not possible to take any particular β(VI) X-ray powder diffraction pattern as a standard for the β(VI) phase of all cocoa butters.     

Comparision of acidic and basic volatile compounds of cocoa butters from roasted and unroasted cocoa beans

A total of nine acidic and 83 basic compounds was identified in the roasted and unroasted cocoa butter samples. Forty seven of the compounds identified are being reported for the first time in cocoa. The higher concentration of short chain fatty acids in the unroasted cocoa butter is responsible for its acidic aroma characteristics. The roasted cocoa butter generally contained greater numbers and higher concentrations of compounds whose formations would be favored by thermal processing. These compounds included pyrazines, thiazoles, oxazoles and pyridines. The aromas of many of these compounds are characteristic of the aroma differences between the two cocoa butters and contribute to the cocoa aroma of roasted cocoa butter.     

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.     

Determination of the adulteration of butter

The adulteration of butter is a serious problem due to economic advantages taken by replacing expensive milk fat with cheaper oil without informing the customers. The authentication of milk fat methods include analysis of bulk components, especially triacylglycerols, fatty acids, sterols and tocopherols. Fatty acid and sterol composition was analysed by using GC‐MS. TAG and tocopherol profiles were examined by HPLC with diode array (DAD) and fluorescence detectors (FLDs). In addition, identification of selected TAG of butter fat was conducted by LC‐atmospheric pressure chemical ionisation (APCI)/MS technique. The lipid composition of 16 different butters available on Polish market were investigated. The cholesterol content in butter fat ranged from 176.8 to 264.8 mg/100 g of fat and in two samples of milk fat β‐sitosterol was found. The total saturated fatty acid (SFA) content in milk fat was 67.1–73.5%, monounsaturated fatty acid 24.5–30.5% and polyunsaturated fatty acid was 1.2–2.0%. Abnormalities in fatty acid profiles, e.g. high concentration of linoleic fatty acid, were found in two butters. These abnormalities were also determined in TAG profiles. The examination of tocopherols in butter fat confirmed that two products were adulterated by the addition of plant oils because they contained δ‐tocopherol which is typical for plant origin foodstuffs. The methods described are useful for investigating milk fat adulterations, and the most efficient are analysis of sterols and tocopherols composition. Practical applications: The described methods are useful for investigating adulteration of milk fat. Traditional strategies rely on examination of fatty acids methyl esters and TAG; these methods have some disadvantages. Due to the variability of fatty acid composition of milk fat and because TAG analysis is complex and time consuming, FA analysis is not an efficient approach for butter authentication. The most efficient method for butter authentication is qualitative and quantitative analysis of sterols and tocopherols. This analysis will determine if components of plant origin were used for butter production.     

Lipid and hardness characteristics of cocoa butters from different geographic regions

Twenty-four commercially pressed cocoa butters and 39 laboratory solvent extracted cocoa butters were evaluated. A rapid method using differential scanning calorimetry (DSC) was used to evaluate the hardness of small quantities of cocoa butter. In the DSC thermogram of a quenched sample, the percentage area under the polymorph II endotherm had a positive correlation (r=0.74) with the mechanical hardness. Soft cocoa butters were characterized by high POO, SOO content (P=palmitic acid, O=oleic acid, S=stearic acid), high iodine value, low percentage, area under the polymorph II endotherm from the DSC scanning, and low SOS. Hard cocoa butters displayed opposite characteristics. In general, South American cocoa butters were the softest and had a 37.03 iodine value, a total of 9.1% POO and SOO, and a 26.4% area under the polymorph II endotherm. Cocoa butters from Asia and Oceania were the hardest and had a 34.74 iodine value, a total of 4.1% POO and SOO, and a 35.65% area under the polymorph II endotherm. North and Central American and African cocoa butters were intermediate in hardness characteristics.     

Crystallization of Cocoa Butter in Cocoa Powder

Cocoa powder quality is determined by its color, flavor, dispersion, and flow properties, which can be controlled via tempering. Design of a cocoa powder tempering profile, however, requires that the mechanism of cocoa butter crystallization in cocoa powder be fully understood. Low-fat (8–12%) and high-fat (20–24%) cocoas were sourced from two commercial manufacturers at varying degrees of alkalization and compared with two commercial cocoa butters. Unrefined paired cocoa powders and cocoa butters sampled from the hydraulic press were also evaluated. Isothermal crystallization kinetics and polymorphism of cocoa powders and cocoa butters were compared at 18, 21, and 24 °C using a direct time-domain nuclear magnetic resonance method, differential scanning calorimetry, and x-ray diffraction. Crystallization was also studied under dynamic tumbling conditions. It was found that cocoa butter in cocoa powder was nucleated by the cocoa powder matrix and transitioned to higher-stability polymorphs more rapidly than bulk cocoa butters. High-fat cocoas also exhibited enhanced crystallization kinetics relative to low-fat cocoas, showing that differences in the cocoa microstructure may influence crystallization behavior. Notably, alkalization did not significantly affect the crystallization behavior of most cocoa powders. Finally, it was found that tumbling conditions led to crystallization of βV and that caking, especially of high-fat cocoas, could be reduced by a static low-temperature hold step prior to tumbling. Overall, these results demonstrated that crystallization of cocoa butter in cocoa powder is influenced both by the intrinsic attributes of the cocoa powder as well as the conditions of the tempering process.     

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.     

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.     

Dynamic crystallization of cocoa butter. I. characterization of simple lipids in rapid- and slow-nucleating cocoa butters and their seed crystals

Six cocoa butters with different crystallization induction times and their seed crystals were analyzed for simple lipid composition. The rapid-nucleating cocoa butter samples had higher concentrations of 1-palmitoyl-2-oleoyl-3-stearoylglycerol and 1,3-stearoyl-2-oleoylglycerol (SOS), and lower concentrations of the diunsaturated triacylglycerols, 1-palmitoyl-2,3-oleoylglycerol and 1-stearoyl-2,3-oleoylglycerol, as well as higher stearic acid concentrations within their diacylglycerol fractions when compared to the slow-nucleating samples. At the early stages of crystallization, under agitation conditions at 26.5°C, cocoa butters solidified into two fractions, high-melting and low-melting. The low-melting fractions were composed of polymorphs IV and V of cocoa butter, as indicated by the onset melting temperatures of the endotherms from differential scanning calorimetry. The high-melting fractions, which had wide melting ranges, had peak maxima of 38.5–52.2°C. Seed crystals isolated at the early stage of crystallization were characterized by high concentrations of complex lipids, saturated triacylglycerols, saturated fatty acid-rich diacylglycerols, and monoacylglycerols. The rapid-nucleating seed crystals had higher concentrations of SOS when compared to their respective cocoa butters. The slow-nucleating seed crystals did not exhibit this characteristic.     

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.     

Dynamic crystallization of cocoa butter. II. Morphological,thermal, and chemical characteristics during crystal growth

After an induction period, crystallization of cocoa butter under dynamic conditions at 26.5°C occurs in two stages, primary and secondary. The primary stage involves nucleation, crystal growth, aggregation, and sintering. Crystals formed during the primary stage were slightly or non-birefringent, and had long, irregular-shaped filaments. The secondary stage was initiated by the formation of spherulites. Total crystallization time may depend upon the crystal growth rate in the primary stage and the time that coca butters take to form the spherulitic crystals in the secondary stage. After the spherulitic crystals formed, the crystal growth rates were rapid. Cocoa butters crystallized into two fractions during the primary and secondary stages. The low-melting fractions had onset melting temperatures similar to those of polymorphs IV and V of cocoa butter. The high-melting fractions, which were observed at the latter stages of crystallization, had differential scanning calorimetry endotherms with peak maxima at approximately 34–36°C (Form VI). The concentrations of 1,3-stearoyl-2-oleoylglycerol (SOS) in the crystals during growth were higher than those in the original cocoa butter. As crystallization progressed, crystals increased in their proportions of SOS in the triacylglycerol fraction. Concentrations of the C₁₈ free fatty acids were lower during early crystallization as compared to the original cocoa butter.     

Assessment of resin formulations and determination of the formaldehyde to urea molar ratio by near‐ and mid‐infrared spectroscopy and multivariate data analysis

The molar ratios of formaldehyde (F) to urea (U) of three resin formulations in the range from 0.90 to 1.49 have been analyzed by means of Attenuated Total Reflection‐Fourier Transform Infrared (ATR‐FTIR) spectroscopy and Fourier Transform‐Near‐Infrared (FT‐NIR) spectroscopy. Application of Principal Component Analysis (PCA) to the spectra (MIR and NIR) allowed to separate them according to the molar ratio and to distinguish between two groups of resins. Soft Independent Modeling of Class Analogy (SIMCA) allowed classification of new resin samples with high model distances between the classes. Partial Least Squares Regression (PLS‐R) models based on MIR (NIR) spectra resulted in high coefficients of determination (R²) values, low errors, and high residual prediction deviations (RPD). To confirm the reproducibility of the process and to carefully evaluate twice all multivariate analysis results obtained, different batches of resins have been prepared to have an additional independent sample set. The number of samples required for MIR and possible applications of MIR and NIR spectroscopy in this context including limitations have been discussed. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013     

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.     

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.     

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.     

Impacts of Bleaching and Packed Column Steam Refining on Cocoa Butter Properties

Natural and alkalized cocoa butters were bleached and subsequently steam refined in a continuous packed column at temperatures ranging between 160 and 220 °C. None of the processes evaluated gave rise to any detectable formation of trans fatty acids, interesterification or polymerization. For the pressures and steam injection rates used, packed-column steam refining required a minimum temperature of 170 °C to achieve acceptable taste. Bleaching was highly effective in preventing darkening at high steam-refining temperatures, as well as in removing alkaloids, such as theobromine and caffeine, before steam refining. The impacts on the crystallization properties of cocoa butter were studied using DSC and P-NMR. The more significant changes in crystallization kinetics and equilibrium values can be reliably predicted on the basis of FFA removal from the butter.     

DSC-Thermoanalyse und Kinetik der Kristallisation von Kakaobutter

DSC-Thermal Analysis and Kinetics of Cocoa Butter Crystallization A DSC method for isothermal crystallization of cocoa butter is described. The crystallization curves may be linearized according to the empirical Avrami equation. From the resulting Avrami plots the rate constant of crystallization may be calculated. This method gives valuable results about the specific crystallization tendency of cocoa butters of different origins and about temperature influence on crystallization times. The method seems to be useful for quality control of cocoa butters and for process control during the tempering step of the industrial chocolate production.     

Application of Infrared Spectroscopy for Characterization of Dietary Omega‐3 Oil Supplements

Fish oil dietary supplements have been linked with health benefits, due to high omega‐3 concentration. The sources of these effects, polyunsaturated fatty acids such as eicosapentaenoic acid and docosahexaenoic acid, are almost exclusively found in seafood products. Our objectives were to characterize the composition of commercial omega‐3 dietary supplements dietary supplements and to generate partial least square regression (PLSR) models using infrared spectroscopy and chemometrics. Fatty acid (FA) composition of oils was determined by FA methyl ester gas chromatography. The supplements encompassed a wide range of FA profiles and delivery methods. Infrared spectral data were collected by portable mid‐infrared Fourier transform infrared (MID FT‐IR) equipment. Principal components analysis (PCA) separated samples based on the type of ester present in the fish oil dietary supplements, showing a strong influence of the 1038 cm^?1 band, which is typically associated with C=C and C–O stretching vibrations. In addition, PLSR was used to correlate the spectra data with GC‐FAME results. PCA using the spectroscopy data allowed for tight clustering of fish oil into distinct classes, depending on the source and processing. PLSR using MID FT‐IR spectra and FA composition generated multivariate models with high correlation coefficient (R ≥ 0.93), and SEP between 0.53 and 2.13 g of FA per 100 g of oil. Our results indicate that IR spectroscopy combined with chemometrics provides for robust screening of FA composition of fish oil supplements, and discriminate types of FAs esterification.     

Phospholipid concentration in cocoa butter and its relationship to viscosity in dark chocolate

Fats extracted from chocolate liquor with a polar solvent, chloroform-methanol, was found to be 0.65% phospholipid. The evidence indicates that the phospholipids are associated primarily with the nonfat solids since concentrations were much lower in fat recovered with nonpolar solvents, hydraulic pressing and centrifugation. Seven of the 11 commercial cocoa butters analyzed had phospholipid concentrations between 0.05% and 0.13%. The highest concentration found was 0.57%. The reduction in viscosity caused by the addition of these butters, 14% by weight, to chocolate was related to the phospholipid concentration in cocoa butter. The higher the phospholipid level, the greater was the viscosity-reducing effect of the cocoa butter. Paper No. 3518, Journal Series of the Pennsylvania Agricultural Experiment Station.