Fat Bloom and Chocolate Structure Studied by Mercury Porosimetry

The structure of dark chocolate samples was analyzed by mercury porosimetry in order to determine whether the formation of fat bloom was related to the presence of pores. The influence of cocoa butter concentration and tempering conditions on porosity were determined by using samples containing 29.5 or 31.9% fat, which were under, well or over-tempered. All Mercury porosimetry analysis confirmed the presence of a porous structure in all chocolates. Empty spaces represented about 1% of the whole volume of a well-tempered chocolate containing 31.9% cocoa butter but made up about 4% of the over-tempered chocolate. A well-tempered chocolate with only 29.5% cocoa butter showed the presence of about 2% empty spaces. From these observations and gas permeability a possible model for the microscopic structure was developed.     

Tempering of Chocolate in a Scraped Surface Heat Exchanger

Crystallization of dark chocolate during different tempering processes has been studied in-situ in a lab-scale Scraped Surface Heat Exchanger. The linear relationship between torque and viscosity made possible the control of chocolate crystallization during tempering by following torque variations vs. time and converting them to equivalent viscosity values. These variations of equivalent viscosity of chocolate observed during tempering were correlated with temper-meter measurements which had been related to the content of cocoa butter seeding crystals. A temperature cycle (50-26.1-30.5-33.3°C) enabled preparation of a well-tempered chocolate stable for ≥30 min at that temperature. It was characterized by a seed crystals content of about 1.15 ± 0.1% of cocoa butter, crystallization temperature of 23.9 ± 0.2°C in the temper-meter and an equivalent viscosity of 3.0 ± 0.4 Pa.s.     

The application of Borneo tallow in dark chocolate shell

Dark chocolate shells, formulated using cocoa butter (CB shell), and fat blends containing 15% Borneo tallow (IP) in cocoa butter (CBIP shell), were filled with truffles formulated using white chocolate (W truffle), milk chocolate (M truffle) and dark chocolate (D truffle). Anhydrous milk fat (AMF) content of the W truffles, M truffle and D truffle were 26·3%, 13·7% and 9·2%, respectively. Degree of tempering was determined using a tempermeter. The chocolates were kept at ambient temperature (25·5±0·5°C) for 3 months. Physical changes of chocolate shells and centres were monitored using DSC and a texture analyser. Results showed that the CBIP shell had to be tempered at 32·5%, ie 1°C higher than the normal CB shell. Physical measurements indicated the occurrence of fat migration. The presence of IP reduced the effect and increased the bloom resistance of the chocolate. © 1998 SCI.     

Improvement of melting and crystallisation properties of rambutan seed fat as cocoa butter improver by two-stage fractionation technique

The search for hard fats is increasing by the day due to their demand for industrial purposes. Rambutan seed fat (RSF) was fractionated prior to investigate the melting and crystallisation behaviours, triacylglycerols (TAGs), and morphology using different chromatographic and thermal techniques. The increasing trends were observed for high-melting symmetrical monounsaturated TAGs such as 1,3-distearoyl-2-oleoyl-glycerol and 1-palmitoyl-3-stearoyl-2-oleoyl-glycerol in both solid fractions upon fractionation. The solid fractions (F₁-S) and (F₂-S) exhibited small peaks towards low melting area and big peaks towards high melting area with the offset temperatures of 35.29–48.75 °C and 43.58–52.70 °C with significantly higher enthalpies (93.49 and 105.13 J g⁻¹) upon fractionation. F₂-S showed the densely packed microstructure compared to that of crude RSF and F₁-S. Based on the thermal behaviours as well as morphology of RSF fractions, cocoa butter improver could be prepared that has the potential to be utilised in chocolate manufacturing in tropical countries.     

Effect of cocoa butter replacement with a β‐glucan‐rich hydrocolloid (C‐trim30) on the rheological and tribological properties of chocolates

BACKGROUND: The food industry has been facing the challenge of developing low‐fat and low‐calorie food products due to rising health awareness of consumers. To meet this consumer demand, an oat β‐glucan‐rich hydrocolloid (C‐trim30) was evaluated as a cocoa butter substitute in chocolates. The effects of C‐trim30 on the rheological, tribological, and textural properties of chocolates were investigated. RESULTS: The viscosity of molten chocolates increased with increasing levels of C‐trim30. Flow behaviors analyzed using the Casson model showed that the Casson viscosity and yield stress increased with increasing concentration of C‐trim30 in the chocolate. Tribological tests on a ball‐on‐flat tribometer showed a reduction in boundary coefficients of friction, with increasing C‐trim30. In addition, hardness of chocolates showed that replacement of cocoa butter with C‐trim30 produced chocolates with softer texture. CONCLUSIONS: The cocoa butter replacement with C‐trim30 up to 10% produced soft chocolates with improved boundary lubrication properties. Also, the chocolate prepared by replacing the cocoa butter with C‐trim30 resulted in a product with a lower caloric value and increased health benefits from the oat β‐glucan. Copyright © 2008 Society of Chemical Industry     

Enzymatically Modified Beef Tallow as a Substitute for Cocoa Butter

ABSTRACT: Dark "chocolate" samples were formulated with either cocoa butter (CB), randomized tallow (RT) made with Candida antarctica (SP 435) lipase, or a beef tallow: stearic acid structured lipid (SL) made by acidolysis using Rhizomucor miehei (IM 60) lipase. Fatty acid composition, thermal profile, solid fat content (SFC), hardness, and polymorphic structure were determined for the fats and/or "chocolate" samples. An accelerated fat bloom study was performed on the "chocolate" samples. Neither of the modified tallows had a detrimental effect on the crystallization of CB after proper tempering of the "chocolates." RT did not soften the "chocolate" and both of the modified lipids reduced bloom rates.     

Review of cocoa butter and alternative fats for use in chocolate—Part A. Compositional data

This work reviews the literature on the compositional data of vegetable fats used or proposed as alternatives to cocoa butter in chocolate and confectionery products. Cocoa butter is the only continuous phase in chocolate, thus responsible for the dispersion of all other constituents and for the physical behaviour of chocolate. Unique to cocoa butter is its brittleness at room temperature and its quick and complete melting at body temperature. There were, and are, strong efforts to replace cocoa butter in part for chocolate production for technological and economic reasons. Such cocoa butter alternatives are the so-called cocoa butter equivalents (CBEs), cocoa butter substitutes (CBSs) and cocoa butter replacers (CBRs). These are mostly mixtures of various vegetable fats (often modified) and can consist of palm and palm kernel oil, illipé fat, shea butter, sal fat and kokum butter. In addition, a large variety of other vegetable oils can be used. Their composition according to triglycerides, fatty acids, sterols and other unsaponifiable components is discussed in this report.     

Monitoring Tempered Dark Chocolate Using Ultrasonic Spectrometry

Ultrasonic spectrometry was used to distinguish between properly tempered and untempered commercial dark chocolate. X-ray diffraction (XRD) and differential scanning calorimetry (DSC) were used to characterize the polymorphic state of tempered and untempered chocolate, results that were correlated to those of ultrasonic spectrometry. Four different kinds of dark chocolate samples with different amounts of sugar (7.5–50 %), fat (30–50 %), and cocoa mass (70–90 %) were subjected to two different tempering protocols. The tempering was achieved using cocoa butter seeds under static cooling from 50 to 14 °C. The ultrasonic generator and analyzer SIA-7 (V.N. Instruments) was used to monitor the crystallization process. The instrument generated a chirp signal with a bandwidth of 0.5 to 3 MHz and was set to work in a four-pathway configuration with two transducers and a center frequency of 2.25 MHz. Spectrometric analysis was carried out with chocolate samples containing 2, 4, and 6 % solid fat content (SFC). The SFC was obtained from DSC measurements. Ultrasonic signals for attenuation, reflection, and velocity were compared between tempered and untempered chocolates. It was shown that seed-tempered chocolate with 30 % sugar and 47.5 % fat attenuated 2.5 MHz of ultrasonic waves by 0.8, 1.7, and 2.0 dB/cm at 2, 4, and 6 % SFC, respectively. On the other hand, untempered chocolate attenuated the ultrasound signal by 3.5, 3.6, and 4.3 dB/cm. Furthermore, it was found that ultrasound reflection signals were stronger and ultrasonic velocity was higher in chocolates with high sugar content.     

Solid Fat Content,Pre-Crystallization Conditions,and Sensory Quality of Chocolate with Addition of Cocoa Butter Analogues

The objective of this study was to determine how the addition of two cocoa butter equivalents and cocoa butter improver affect the physical and sensory properties of chocolate. The laboratory-made chocolate samples were tempered at three different pre-crystallization temperatures (25, 27, and 29°C), using different concentrations (3, 5, and 7%) of two commercial cocoa butter equivalents as well as commercial cocoa butter improver of the chocolate. The nucleation time of the chocolate mass primarly depended on pre-crystallization temperature while the value of maximum torque of chocolate mass were influenced by both, pre-crystallization temperature and concentration of fats. Sensory evaluation revealed that cocoa butter equivalents were acceptable in chocolate formulation without producing a negative impact on the sensory quality, while usage of improver required adjustment of raw formulations or process parameters. The results of the instrumentally measured hardness revealed that addition of cocoa butter improver significantly (p > 0.05) increased hardness of chocolate samples.     

芒果脂提高巧克力抗霜性的研究

StOSt是芒果脂的特征成分,也是解决巧克力在炎热和冷链缺乏地区软化和起霜问题的关键成分。然而,在应用中发现StOSt虽提高巧克力的耐热性,却可能加速起霜。本文将芒果脂与可可脂复配,制备巧克力油基,分析其甘油酯、甘油三酯组成和熔化行为,进而研究相应巧克力的抗霜性能。结果表明：芒果脂含StOSt 44.7%、低熔点甘油三酯23.9%、甘油二酯8.3%,其中低熔点甘油三酯和甘油二酯含量均显著高于可可脂;其与可可脂复配所得油基的StOSt/POSt/POP比值接近4.0/2.5/1.0且甘油二酯含量为6%~8%时,可延缓油基从V向VI晶型转换,从而提高了所制备巧克力的抗霜性。本文为类似富含StOSt的油脂在抗霜巧克力中的应用提供科学参考。     

Derivation of a Cocoa Butter Equivalent from Jojoba Transesterified Ester via a Differential Scanning Calorimetry Index

A series of wax ester blends was constructed by transesterifying native jojoba oil with 50–500 g kg⁻¹ completely hydrogenated jojoba wax esters. This series, when subjected to a standardised differential scanning calorimetry (DSC) tempering method gave either 1, 2 or 3 enthalpic events which represented the diunsaturated, monounsaturated and saturated species. These species were verified by measuring the melting points of a native and completely hydrogenated jojoba wax ester and also by demonstration that DSC thermograms of a synthetic monounsaturated wax ester possessed an endotherm with a melt between the diunsaturated and completely saturated species. The heats of fusion and heats of crystallisation enthalpies of all three enthalpic events exhibited excellent correlation with the level of saturation. Chemometric indices were devised from heats of fusion and crystallisation enthalpies to estimate the level of saturation in these blends. From these indices and also from regression analyses of each species' individual events we could optimise the level of saturation needed to best mimic the melt and crystallisation properties of cocoa butter. The wax ester blend with 400 g kg⁻¹ saturation most closely resembled the thermal properties of cocoa butter where the monounsaturated species of the jojoba blend gave identical thermograms to tempered cocoa butter.     

类可可脂原料油中低熔点甘油三酯的组成、含量调控与综合利用

为了实现类可可脂在巧克力中更为高效的应用,降低其对产品品质的影响,综述了类可可脂原料油中低熔点甘油三酯的组成与熔化性质,概括了不同种类甘油三酯对巧克力霜变行为的作用特征;进一步讨论了控制低熔点甘油三酯含量的技术方法,包括基因工程和分提;最后,总结了经分提获得的低熔点成分的再利用。类可可脂原料油中低熔点甘油三酯可能对巧克力的制造(尤其是调温)和质量控制(如软化、起霜等)产生不利影响。通过分提选择性降低低熔点甘油三酯含量是制备高品质类可可脂的优选路径。     

Modelling tempering behaviour of dark chocolates from varying particle size distribution and fat content using response surface methodology

Central Composite Rotatable Design (CCRD) for K = 2 was used to study the combined effects of multi-stage heat exchangers for Stages 1 (14–30 °C) and 2 (12–28 °C) coolant temperatures at constant Stage 3 coolant and holding temperatures during tempering of dark chocolates using laboratory-scale mini-temperer. Quantitative data on chocolate temper index (slope) were obtained for products with varying particle size distribution (PSD) (D₉₀ of 18, 25, 35 and 50 μm) and fat (30% and 35%) content. Regression models generated using stepwise regression analyses were used to plot response surface curves, to study the tempering behaviour of products. The results showed that both Stage 1 and Stage 2 coolant temperatures had significant linear and quadratic effects on the crystallization behaviour causing wide variations in chocolate temper index during tempering of products with variable PSD and fat content. Differences in fat content exerted the greatest variability in temperature settings of the different zones for attaining well-tempered products. At 35% fat content, changes in PSD caused only slight and insignificant effect on tempering behaviour. No unique set of conditions was found to achieve good temper in dark chocolate with a specified tempering unit. Thus, different combinations of temperatures could be employed between the multi-stage heat exchangers to induce nucleation and growth of stable fat crystal polymorphs during tempering. Variations in tempering outcomes of the dark chocolates were dependent more on the fat content than PSD.

Industrial relevance

Tempering consists of shearing chocolate mass at controlled temperatures to promote cocoa butter crystallization in a stable polymorphic form. During industrial processing, multi-stage heat exchangers are used to control temperature adjustments to promote formation of appropriate stable polymorphic crystals to obtain products with good snap, colour, contraction, gloss and shelf life characteristics. The process employs varying time–temperature throughputs of the multi-stage units making it difficult to obtain standard tempering conditions for products with variable particle sizes and fat content, thus prolonging equipment standardization periods with consequential effects on processing times and product quality characteristics. Modelling the tempering behaviour of dark chocolates from varying PSD and fat content would enhance our knowledge and understanding on the optimal temperature conditions for obtaining good tempered products during industrial manufacture, with significance for reducing processing (tempering) times and assurances in quality and shelf characteristics.     

Cocoa butter fats and possibilities of substitution in food products concerning cocoa varieties,alternative sources,extraction methods,composition, and characteristics

The current concern for cocoa butter fat as major ingredients of chocolate intake in the World has raised the question of the high price of cocoa butter among all other vegetable fats. Productions of natural cocoa butter fats are decreasing day by day due to the decrease of cocoa cultivation worldwide; moreover, cocoa fruit contains only a little amount of cocoa butter. Therefore, the food industries are keen to find the alternatives to cocoa butter fat and this issue has been contemplated among food manufacturers. This review offers an update of scientific research conducted in relation to the alternative fats of cocoa butter from natural sources. The findings highlights how these cocoa butter alternatives are being produced either by blending, modifying the natural oils or fats from palm oil, palm kernel oil, mango seed kernel fats, kokum butter fat, sal fat, shea butter, and illipé fat.     

巧克力用脂肪替代品——类可可脂

<正> 巧克力产品的质量,如软硬度、口感细腻度、风味特性等,主要取决于其配料成分的质量及加工工艺的优化程度。作为巧克力产品的主要成分,可可脂和乳脂的种类及功能特性是重要的生产及质量指标。基本上,可可脂和乳脂都是取自天然的原材料,在不同的季节、产地来源所得的质量均会有所不同,要保持产品质量稳定一致,对巧克力生产商来说无疑是一项大挑战。 为了解决这个难题,食品配料及添加剂生产商一直致力于研究开发各     

巧克力食品中可可脂及其代用品的鉴别研究

巧克力食品中的常用油脂主要包括天然可可脂、类可可脂、代可可脂和乳脂,采用高温气相色谱法对这四种油脂的甘油三酯组成进行分离。结果表明,天然可可脂与类可可脂的甘油三酯组成较相似,但与代可可脂完全不同,乳脂的甘油三脂组成非常复杂,以其特殊的峰型区别于其它各脂。通过甘油三酯组成的谱图特征可快速、直观地鉴别出这四种油脂。实际应用可区分市售可可脂巧克力和代可可脂巧克力。     

纯脂巧克力用脂及其分析、应用研究进展

近年来纯脂巧克力日渐受欢迎,但可可原料面临产量有限且不稳定的制约因素,限制了纯脂巧克力的发展。作为与可可脂组分及特性最为接近的可可脂替代品,类可可脂的原料来源广泛,产品稳定性有提升空间,并且在提升纯脂巧克力品质方面有改善作用,因此类可可脂的相关研究也获得国内外广泛关注。通过对可可脂及类可可脂的组成、结晶特性、分析方法及纯脂巧克力的耐霜、抗热品质改善等方面进行综述,以期对纯脂巧克力用脂、巧克力品质改善等提供相关参考。     

Characteristics of palm mid-fractions produced from different fractionation paths and their potential usages

Three palm mid-fraction (PMF) groups produced from different fractionation paths were analyzed in terms of the fat, triacylglycerol and sn-2 fatty acid compositions, thermal properties (melting and crystallization behaviors, and solid fat contents (SFCs)), micronutrient levels and oxidative stability indexes (OSIs) to achieve their sufficient utilization. PMF-A (iodine value (IV), 48.4 g/100 g) fractionated from palm olein contained 43.8% 1,3-dipalmitoyl-2-oleoyl-glycerol (POP) and 16.7% 1-palmitoyl-2,3-dioleoyl-glycerol, showing soften properties (slip melting point (SMP), 27.6°C; SFC at 30°C, 2.2%) at hot weather. PMF-B (IV, 42.3 g/100g) obtained from palm stearin showed similar fat and triacylglycerol compositions as PMF-A, but the high 1,2,3-tripalmitoyl-glycerol level (6.2%) improves its thermal behaviors (SMP, 34.9°C; SFC at 30°C, 13.8%). The SFC profiles of PMF-A and PMF-B were comparable to those found in frozen and puff margarine shortenings. Furthermore, both of the PMF groups exhibited excellent OSIs (13.2 and 11.2 h, respectively) because of their high micronutrient levels (especially γ-tocopherol and campesterol). In general, γ-tocopherol and campesterol contribute to preventing lipids from oxidation under frying conditions. Therefore, PMF-A and PMF-B are recommended for manufacturing margarine shortenings and frying fasts. PMF-C (IV, 33.0 g/100g) produced from the additional fractionation of PMF-A or PMF-B contained the highest POP percentage (67.1%) and showed heat-resistant property (SMP, 31.8°C; SFC at 30°C, 22.4%). Its steep SFC profile was superior to that of cocoa butter, suggesting the fat is preferred in producing hard chocolate fats.