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1.
Summary The content of purine alkaloids in seeds of fourTheobroma species from the Amazon basin was analized by a reversed phase high-performance liquid chromatographic method.Theobroma grandiflorum was found to contain 0.38% of 1,3,7,9-tetramethyluric acidT. subincanum 0.07% 1,3,7,9-tetramethyluric acid,T. speciosum 0.01% theobromine and 0.04% 1,3,7,9-tetramethyluric acid and finallyT. mariae 2.35% theobromine and 0.12% caffeine. Theophylline could not be detected in any of these species. The results were confirmed qualitatively by thin-layer chromatography.
Purinalkaloide in Samen vonTheobroma-Arten aus dem Amazonas-Becken
Zusammenfassung Das Vorkommen von Purin-Alkaloiden in Samen von vierTheobroma-Arten des Amazonasbeckens wurde mit Hilfe einer RP-HPLC-Methode untersucht. In Samen vonTheobroma grandiflorum wurden 0,38% 1,3,7,9-Tetramethylharnsäure (TMU), vonT. subincanum 0,07% TMU, vonT. speciosum 0,01% Theobromin und 0,04% TMU sowie schließlich vonT. mariae 2,35% Theobromin und 0,12% Coffein gefunden. Die Ergebnisse wurden qualitativ dünnschichtchromatographisch bestätigt.
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2.
Samples of two types of palm mid-fraction (PMF I, a commercial sample and PMF II, from a laboratory-scale acetone fractionation of PMF I) and a Malaysian deodorised cocoa butter sample were used as the main components in the fat phase for white chocolate formulation. The monounsaturatedtriacylglycerol contents of these fats were 853, 899 and 903 g kg−1, respectively.All the fats had free fatty acid contents of less than 10 g kg−1 and melting points in the range of 34·0–34·5°C. The solid fat content profiles for the three fats were very steep. Differential scanning calorimeter analyses showed that all the fats had two melting peaks, T1 and T2. Results of the study showed that the tempering time to produce a well-tempered chocolate using PMF I was longer than that using PMF II, whereas, the time to produce a well-tempered cocoa butter chocolate increased with increase in the tempering temperature. Chocolates made with PMF I and II were well tempered between 17 and 19°C and with cocoa butter at 23°C. Thermal analyses, carried out on the chocolate showed that PMF I and II produced three melting peaks, T1, T2′ and T2 whereas most of the cocoa butter chocolates exhibited only one melting peak, T2. Storage studies showed that most of the chocolates had good bloom resistance for up to 12 weeks storage.  相似文献   

3.
This paper describes the preparation of samples and the evaluation techniques applied to determine the Solid Fat Content (SFC) by means of pulsed nuclear magnetic resonance (NMR) in confectionery fats characterized by distinct polymorphism (cocoa butter, cocoa butter equivalents and their mixtures). Due to the deviation of SFC values in certain softer cocoa butter equivalents at the temperature of 20 °C, an internal method devised at Karlshamns Oils & Fats AB is applied as well. When compared to the official IUPAC 2.150 (b) method, Karlshamns' method involves a lower temperature and a prolonged period of time at the stage of the final SFC stabilization in the pre-treatment of fat samples. The calculation of SFC in the analysed samples for the purposes of this paper was carried out by employing both methods (the indirect method and a serial procedure). The results are presented graphically. Differences were reflected in the SFC of the fats and their mixtures that were under observation depending on the method and temperatures applied. The obtained results indicated a considerable advantage of employing the Karlshamns method since the results yielded by this method are more lucid. Moreover, the behaviour of fats in the production process can be more easily predicted on the basis of these results.  相似文献   

4.
Recent interest in the development of the tallow tree (Pentadesma butyracea S) as an oil-tree crop has stimulated agronomic and chemical studies of the tree and the fat obtained from its seeds. Tallow fat extracted from local seeds has been analysed for its chemical and physical constants and fatty acid composition. These characteristics have been compared with those of the better known cocoa butter and shea butter. Dry tallow kernels, shea butter kernels and cocoa beans contained 50, 52.1 and 53.4% fat, respectively. Tallow fat and shea butter are similar in several of their characteristics, particularly slip point, saponification number, solidification point and fatty acid composition; but tallow fat has a much lower unsaponifiable matter content (1.5–1.8%) than shea butter (7.3–9.0%). Both are markedly different from cocoa butter and cocoa butter replacement fats in respect of their melting points and fatty acid composition. Cooling curves of 3:1, 1:1, and 1:3 mixtures of tallow fat and cocoa butter indicate poor compatibility between the two fats.  相似文献   

5.
《Food chemistry》1998,62(1):73-97
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.  相似文献   

6.
Zusammenfassung:  Die Gattung Theobroma umfasst etwa 20 Arten, von denen insbesondere die Art Theobroma cacao L. mit den beiden Hauptsorten (Variet?ten) „Criollo“ und „Forastero“ wirtschaftliche Bedeutung hat. Bislang erfolgte die Unterscheidung der Kakaosorten und -arten nur morphologisch und, dadurch bedingt, nur in einem sehr frühen Verarbeitungsstadium, d. h. eine Reinheitskontrolle ist zu einem sp?teren Zeitpunkt nicht mehr m?glich. Andererseits erfolgt die Herstellung von Kakaomasse heute zunehmend im Erzeugerland, Schokolade oder Kakaohalberzeugnisse werden vom verarbeitenden Unternehmen zugekauft. Eine genaue und reproduzierbare Spezifikationskontrolle ist aus den skizzierten Gründen bislang nicht m?glich. Im Gegensatz zur alten Kakaoverordnung liefert die neue Kakaoverordnung vom 15. Dezember 2003 keine Definition des Kakaos mehr. Die Kakao- und Schokoladenindustrie geht aber nach wie vor davon aus, dass nur die Kakaoart T. cacao bei der Herstellung von Schokolade zur Anwendung kommt (allgemeine Verkehrsauffassung in Anlehnung an die alte Kakaoverordnung). Die Kakaoart T. grandiflorum (Cupuassu) gewinnt auf dem südamerikanischen Markt immer mehr an Bedeutung. Beispielsweise werden die Bohnen vermehrt zu Schokolade-artigen Produkten (Cupu-lade) verarbeitet. Im Rahmen dieser Arbeit wurden eine PCR- und eine PCR-RFLP Methode entwickelt, die eine Detektion beider Theobroma-Arten in Kakao und Schokoladenprodukten erlauben.
The genus Theobroma comprises about 20 species. The highest economic attention is paid to the cultivars (varieties) “Criollo” and “Forastero” of the species Theobroma cacao L., which are used for chocolate production. Up to now, the differentiation of cocoa species and cultivars is performed morphologically. Hince, a purity control in late processing steps of chocolate production is not possible. However, most of the cocoa mass production takes place in the countries of cocoa origin and is then bought as semi-finished products by the chocolate industry. Species identification is not possible at this stage due to the manufacturing process. In the former “Kakaoverordnung” a definition of the cocoa species (T. cacao) used for chocolate production was given. The current “Kakaoverordnung” (passed in December 2003) lacks such a definition. Nevertheless, it is general acceptance in the chocolate industry to exclusively use the species T. cacao for chocolate production. On the other hand, the species T. grandiflorum (Cupuassu) is getting more and more important on the South American market where beans are used for the creation of chocolate-like products e.g. Cupu-late. This work describes the development of a PCR and a PCR-RFLP method for the detection of cocoa species in chocolate products.

Eingegangen: 20. Juli 2007; angenommen: 8. August 2007  相似文献   

7.
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.  相似文献   

8.
Physical characteristics of precrystallised binary mixtures of cocoa butter (CB) and 5, 10, 15, 20, 25 and 30% (w/w) cocoa butter replacer (CBR) or cocoa butter substitute (CBS) were determined. The lipid composition was obtained by chromatography and the solid fat content (SFC) by nuclear magnetic resonance. Tempering was carried out using a lab‐scale agitated jacket vessel reactor. Bars made with tempered samples were submitted to X‐ray diffraction and rupture tests. Snap values of crystallised mixtures decrease with an increase in the amount of alternative fat. X‐ray diffraction patterns confirmed the predominant formation of the beta polymorph habit for CB and beta prime form for CBR and CBS. Mixtures of CB and CBR exhibit chemical compatibility. The knowledge of the snap values and of the variation of SFC with temperature proved to suffice to adequately anticipate the influence of the addition of alternative fats on chocolates physical attributes.  相似文献   

9.
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.  相似文献   

10.
In this study, the effect of interesterification (using sodium methoxide) on physicochemical characteristics of fully hydrogenated palm olein (FHPO)/soybean oil blends (10 ratios) was investigated. Interesterification changed free fatty acid content, decreased oil stability index, solid fat content (SFC) and slip melting point (SMP), and does not affected the peroxide value. With the increase of FHPO ratio, oil stability index, SFC and SMP increased in both the interesterified and non-interesterified blends. Fats with higher FHPO ratio had narrower plastic range, as well. Compared to the initial blends, interesterified fats had wider plastic ranges at lower temperatures. Both the non-interesterified and interesterified blends showed monotectic behavior. The Gompertz function could describe SFC curve (as a function of temperature, saturated fatty acid (SFA) content or both) and SMP (as a function of SFA) of the interesterified fats with high R2 and low mean absolute error.  相似文献   

11.
Cocoa butter equivalent (CBE) was synthesised from blends of illipé butter stearin (IBS) and palm mid-fraction (PMF) via enzymatic interesterification (EIE). IBS was blended with PMF in three wt ratios (70:30, 60:40 and 50:50) and the EIE reactions were performed at 50°C for 30 min using an sn-1,3-specific lipase from Rhizopus oryzae as a catalyst. The triacylglycerol (TAG) compositions, slip melting points (SMP), crystallisation and melting thermograms, solid fat content (SFC) curves, and crystal microstructure of the blends before and after EIE were studied and compared with cocoa butter (CB). After EIE, the contents of POP and StOSt decreased, whereas the POSt content increased in all blends. Blend EIE 60:40 exhibited the POP and StOSt contents that situated within the ranges of POP and StOSt contents of CB. It also showed SMP, melting peak and melting completion temperatures, melting enthalpy and crystal microstructure most similar to CB. Most importantly, its SFC curve completely matched that of CB. Consequently, EIE 60:40 was chosen for further investigation and it was found to be fully compatible with CB and crystallised into the same polymorphic form (β) as CB. Therefore, EIE 60:40 has a high potential for use as a commercial CBE.  相似文献   

12.
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。  相似文献   

13.
This study investigated the effect of six fats (margarine, butter, lard-LAR, refined palm oil-RPO, refined palm oil with stearin-RPOS, hydrogenated palm oil-HPO) with different solid fat content (SFC) on gluten-free oat dough and cookie properties. RPOS and HPO had the highest SFC. RPO dough was the softest, whereas HPO was the hardest one. Dough hardness was correlated with SFC (r = 0.87). Dough stickiness was positively correlated with dough hardness (r = 0.92). Dough hardness influenced the breaking force of the cookies (r = 0.79). HPO were the hardest cookies. Oscillatory test revealed that HPO dough was the stiffest as well as presented a higher rigidity compared to the other samples as showed by the creep tests. LAR cookies were the darkest, while HPO were the lightest. SFC of fats is the most important composition parameter which influences thermal, textural and rheological properties of the oat dough.  相似文献   

14.
Cocoa butter equivalents (CBEs) are fats with a similar composition and melting profile as cocoa butter (CB), which are usually prepared by blending mid-palm fractions and stearate-rich tropical butters. In this regard, high stearic–high oleic sunflower oil contains disaturated triacylglycerols typically present in CBEs, albeit at a lower concentration than that required to produce a solid fat. Here we have assessed a means to fractionate this oil in order to produce solid fractions that can be used as stearic acid-rich butters appropriate for CBE formulations. Solvent fractionation of high stearic–high oleic sunflower oil was optimised in function of the oil/solvent ratio and temperature. Sunflower stearins with similar melting profiles as cocoa butter were obtained from oils of either 17% or 20% stearic acid in a single step. Different stearin products can be obtained by controlling the oil/solvent ratio and the temperature of fractionation. The use of these fractions as CBE components or confectionery fats is discussed in function of their melting profiles.  相似文献   

15.
Structured lipids (SLs) are lipids that have been chemically or enzymatically modified from their natural biosynthetic form. Because SLs are made to possess desired nutritional, physicochemical, or textural properties for various applications in the food industry, many research activities have been aimed at their commercialization. The production of SLs by enzymatic procedures has a great potential in the future market because of the specificity of lipases and phospholipases used as the biocatalysts. The aim of this review is to provide concise information on the recent research trends on the enzymatic synthesis of SLs of commercial interest, such as medium‐ and long‐chain triacylglycerols, human milk fat substitutes, cocoa butter equivalents, trans‐free or low‐trans plastic fats (such as margarines and shortenings), low‐calorie fats/oils, health‐beneficial fatty acid‐rich fats/oils, mono‐ or diacylglycerols, and structurally modified phospholipids. This limited review covers 108 research articles published between 2010 and 2014 which were searched in Web of Science.  相似文献   

16.
The cocoa relatives T grandiflorum (cupuaçu) and T bicolor (macambo) are promising crop plants for sustainable agroforestry in the Amazon region of South America. The market for cupuaçu is expanding since the fruit flesh is utilised by the foodstuffs industry. Attempts to commercialise chocolate‐like wares from the seeds have failed so far because of unreliable product quality. It is not known whether this is due to an insufficient aroma potential of cupuaçu seeds. We therefore investigated the proteolytic enzymes and the seed storage globulins which are both decisive for the formation of aroma precursors in cocoa. We found that the activities of the aspartic endopeptidase and the carboxypeptidase in T bicolor and T grandiflorum differed slightly from those in cocoa. The specificity of the carboxypeptidase for hydrophobic amino acids was quite similar across the three species, while the optimal pH of the T grandiflorum enzyme was lower than that of the other species. The qualitative and quantitative differences between the globulins indicate a lower maximum yield of aroma precursors in T grandiflorum and a higher maximum yield of aroma precursors in T bicolor, compared to cocoa. We conclude that the quality of chocolate‐like products made from the studied cocoa relatives can be improved by adapting fermentation procedures to particular biochemical features of these seeds. Copyright © 2004 Society of Chemical Industry  相似文献   

17.
Cocoa butter replacer (CBR) was prepared by enzymatic interesterification of hydrogenated and solid fraction (SF) of tea seed oil at weight percent ratio of 30:70, using sn‐1,3 specific lipase from Thermomyces lanuginosus. Dark chocolate samples were then prepared with the prepared CBR as a replacement for 5%, 10%, 15% and 20% of cocoa butter (CB) and the effect of the replacement on hardness (as a key quality factor in chocolate) of the chocolate samples was investigated. Results showed that chocolate samples containing 5% and 10% of interesterified sample (EIS), had the closer texture to that of CB chocolate than other samples. The solid fat content (SFC) profiles also revealed that blending 10% of EIS with CB in chocolate formulation dose not affect the sharp melting point of CB. Based on the results taken from bloom formation, polymorphic structure and sensory evaluation, adding up to 10% of EIS in chocolate formulation reduces the bloom development without adverse affecting the desirable β crystal formation and sensory qualities in the chocolate samples.  相似文献   

18.
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。  相似文献   

19.
Trans-free interesterified fats were prepared from blends of hard palm stearin (hPS) and rice bran oil (RBO) at 20:80, 30:70, 40:60, 50:50, 60:40, 70:30, and 80:20 weight % using immobilized Mucor miehei lipase at 60°C for 6 h with a mixing speed of 300 rpm. Physical properties and crystallization and melting behaviors of interesterified blends were investigated and compared with commercial margarine fats. Lipase-catalyzed interesterification modified triacylglycerol compositions and physical and thermal properties of hPS:RBO blends. Slip melting point and solid fat contents (SFC) of all blends decreased after interesterification. Small, mostly β′ form, needle-shaped crystals, desirable for margarines were observed in interesterified fats. Interesterified blend 40:60 exhibited an SFC profile and crystallization and melting characteristics most similar to commercial margarine fats and also had small needle-like β′ crystals. Interesterified blend 40:60 was suitable for use as a transfree margarine fat.  相似文献   

20.
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.  相似文献   

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