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.     

代可可脂花生夹心糖制作工艺优化

以花生糖为糖芯,代可可脂为主要包衣材料,制作代可可脂巧克力花生夹心糖。利用响应面分析法优化糖芯制作工艺。根据Box-Behnken中心组合试验设计原理对工艺条件进行优化,在分析各因素显著性及其交互作用的基础上,得出花生糖芯口感最佳配方为：糖芯的最佳配料为白糖-淀粉糖浆-花生粉末-猪油(添加量质量配比为3.33:4.02:7.24:1),包衣材料的最佳配料为白糖30%、乳化剂0.5%、代可可脂-可可粉8:1(m/m);包衣厚度1.4mm,包衣温度50℃。     

In Situ Ultrasonic Characterization of Cocoa Butter Using a Chirp

Differences between tempered and untempered cocoa butter were investigated by an ultrasonic signal “chirp” generated by contact transducers. Polarized light microscopy and powder X-ray diffraction were used to characterize the morphology and polymorphism of tempered and untempered cocoa butter, whereas pulsed nuclear magnetic resonance was used to determine the amount of crystalline solids present. Ultrasonic wave velocity and attenuation data were collected simultaneously throughout the 5-h crystallization process for cocoa butter. Ultrasonic velocity and attenuation changed at the different solid fat contents (SFC): 4, 8, and 11 %. Untempered cocoa butter showed an attenuation of 3 dB/cm at 1.7 MHz and 4 % SFC, whereas tempered cocoa butter showed an attenuation of 4.5 dB/cm at 1.7 MHz and 4 % SFC. At 3 MHz, the attenuation was 2 dB/cm for untempered and 6 dB/cm for tempered cocoa butter. Under these conditions (4 % SFC, 3 MHz), the chirp wave of tempered sample showed a phase angle change of 0.5 rad, whereas the untempered sample showed ?0.5 rad relative to the canola oil that was taken as 0. The study suggests that an ultrasonic chirp can be effectively used to detect differences between tempered and untempered cocoa butter when measuring attenuation and ultrasonic wave phase angle changes as a function of frequency. The in-line characterization of chocolate “temper” using such nondestructive ultrasonic measurements could be applied to industrial chocolate manufacturing.     

Effects of Moisture and pH on Supercritical Fluid Extraction of Cocoa Butter

The effects of moisture content and alkali treatment on cocoa butter extraction using supercritical fluid were studied. Ground cocoa nibs were examined at moisture contents of 1.95 %, 3.91 %, 5.87 %, 9.79 % and 17.64 % and the pH of the cocoa liquor was maintained at 5.0–5.9, 6.8–7.2 and 7.5–7.9. Cocoa butter was successfully extracted, using supercritical carbon dioxide (SC-CO₂) for the moisture content study and SC-CO₂ with 25 % ethanol as a cosolvent for the pH-level alkali treatment study, at 35 MPa, 60 °C and 2 ml/min. The results showed that increases in moisture content and pH level significantly (p?<?0.05) increase the yield efficiency. A moisture content of 9.79 % and pH-alkali treatment at 7.5–7.9 produced the highest yield (60.36 % and 73.70 % at 20 and 18 h extraction time, respectively). Triglycerides (TG) and fatty acids (FAs) were similar to those found in cocoa butter obtained using the Soxhlet method. Saturated and short-chain TG and FA constituents were more soluble than unsaturated and long-chain constituents.     

小米曲奇预拌粉配方的优化

以预糊化小米粉为主要原材料,研制小米曲奇预拌粉。通过单因素试验,研究小米粉添加量、吉士粉添加量、奶粉添加量、泡打粉添加量、糖粉添加量对小米曲奇感官评分和硬度的影响。采用Box–Behnken法设计试验方案,运用响应面分析法建立二阶多项式非线性回归方程和数值模型,以感官评分和硬度为评判指标,优化小米曲奇预拌粉配方。优化后配方为:小米粉60.00g、低筋面粉40.00 g、吉士粉6.50 g、泡打粉1.00 g、糖粉45.00 g、奶粉8.00 g。在此条件下小米曲奇的理论感官评分为95.04分、硬度为510.11 g。在此配方下制作的小米曲奇呈棕黄色,与市售黄油曲奇相比,具有独特的小米香气和风味。预拌粉降低了小米曲奇制作的专业性、技术性,提高生产效率,利于生产品质稳定、健康味美的小米曲奇产品。     

富含茶多酚能量胶的研制及其抗氧化活性

这项研究旨在研制具有抗氧化功能的能量胶。实验以感官评分、能量密度、DPPH自由基清除率为评价指标,通过单因素试验和响应面试验对产品配方进行优化。结果表明,能量胶产品的最佳配方为:以明胶溶液质量为基准,明胶水溶液浓度为25%,总糖含量(蔗糖:麦芽低聚糖=1:1,m/m)62.43%,蛋白质含量(乳清蛋白:大豆分离蛋白=3:1,m/m)25.4%,植物油24.92%,可可脂25%,复合维生素1.07%,茶多酚0.19%。该产品感官评分为9.13,能量密度为3.37 Kcal/g,DPPH·清除率为83.05%。与市售能量胶和未含茶多酚能量胶进行体外抗氧化能力比较表明:含茶多酚能量胶、市售能量胶和未含茶多酚能量胶对ABTS+·的IC_(50)分别为1.75mg/m L、3.22 mg/m L、5.86 mg/m L;对·OH的IC50分别为0.02 g/m L、0.03 g/m L、0.10 g/m L;总还原能力由强到弱为:含茶多酚能量胶市售能量胶未加茶多酚的能量胶。该能量胶产品具有较强的抗氧化能力和较高的能量密度。     

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.     

Composition of dietary fibre in cocoa husk

 This paper describes the total non-starch polysaccharide (NSP), soluble and insoluble dietary fibre (SDF and IDF) content of processed cocoa husk (cocoa butter <3 g/100 g) determined according to Englyst's enzymatic-chemical procedure. In addition, fibre values were determined by measuring the levels of the composite sugars by spectrophotometry and gas chromatography methods, and the fractions acid-detergent fibre, neutral-detergent fibre, crude fibre, Klason lignin, starch, crude protein, ash, fat, water content, and water-holding capacity (WHC). The NSP content was 43.8±2.32 g/100 g (28.34 g/100 g IDF plus 15.60 g/100 g SDF), the mean soluble fibre concentration was 35.5% of total fibre. Klason lignin content, estimated gravimetrically, was 13.7±1.8 g/100 g. Cellulose (19.7±1.48 g/100 g) and uronic acids (12.4±1.35 g/100 g) were the main type of IDF and SDF substances, respectively. The analysis of neutral sugar constituents showed the presence of glucose, the predominant sugar, followed by arabinose, galactose and xylose. The WHC was 3.62±0.47 g water/g cocoa husk. Received: 19 December 1997 / Revised version: 27 February 1998     

Composition of dietary fibre in cocoa husk

 This paper describes the total non-starch polysaccharide (NSP), soluble and insoluble dietary fibre (SDF and IDF) content of processed cocoa husk (cocoa butter <3 g/100 g) determined according to Englyst's enzymatic-chemical procedure. In addition, fibre values were determined by measuring the levels of the composite sugars by spectrophotometry and gas chromatography methods, and the fractions acid-detergent fibre, neutral-detergent fibre, crude fibre, Klason lignin, starch, crude protein, ash, fat, water content, and water-holding capacity (WHC). The NSP content was 43.8±2.32 g/100 g (28.34 g/100 g IDF plus 15.60 g/100 g SDF), the mean soluble fibre concentration was 35.5% of total fibre. Klason lignin content, estimated gravimetrically, was 13.7±1.8 g/100 g. Cellulose (19.7±1.48 g/100 g) and uronic acids (12.4±1.35 g/100 g) were the main type of IDF and SDF substances, respectively. The analysis of neutral sugar constituents showed the presence of glucose, the predominant sugar, followed by arabinose, galactose and xylose. The WHC was 3.62±0.47 g water/g cocoa husk. Received: 19 December 1997 / Revised version: 27 February 1998     

RHEOLOGICAL BEHAVIOR OF COCOA DISPERSIONS WITH COCOA BUTTER REPLACERS

The steady shear viscosity and yield stress of cocoa powder dispersed in three cocoa butter replacers (CBRs) are measured over a wide range of powder concentration and temperature. The flow activation energies of the three CBRs are nearly the same, and close to that of cocoa butter. Values of intrinsic viscosity of cocoa powder dispersed in corn oil and Socolate 36–38 are in the range of 4.0–5.0, (similar to that in cocoa butter), suggesting that these two CBRs are good cocoa replacers. A lower value of intrinsic viscosity is found for the powder dispersed in Super YZ-2. Viscosity measurements indicate that all three CBR dispersions exhibit Newtonian behavior at low volume fraction, but non-Newtonian shear thinning characteristics when the volume fraction φ > 0.3 at 60C. The non-Newtonian behavior can be described by the Casson model when φ exceeds a critical value, φ mo , the maximum packing fraction at zero shear. The yield stress can be related to the powder volume fraction using a four-parameter equation originally proposed by Zhou et al. (1995).     

Application of D-optimal design for optimizing <Emphasis Type="Italic">Parkia biglobosa</Emphasis> flour-based cookie

The aim of the study was to produce cookie by partial substitution of wheat flour (WF) with Parkia biglobosa Flour (PBF) and use D-optimal design to enhance the baking time (BT), the cookie diameter (CD), the cookie width (CW) and the cookie hardness (CH). The cookie sensory attributes (taste, aroma, texture, colour and overall likeness) were also evaluated in the study. The results established that it is possible to obtain Parkia biglobosa flour-based cookies that have slightly more sensory acceptability than those made from only wheat flour. In general, cookie acceptability was influenced by the different compositions of the formulation. Increasing the proportion of PBF in the composite flour resulted in an increase in width of the cookie as well as induced a significant increase in the hardness of the cookie. The optimum formulation was WF (208.133 g), PBF (200 g) and MA (241.867 g) with a correspondent BT of 7.9266 min, CD of 161.674 mm, CW of 46.3052 mm and CH values of 40.2973 mm with a desirable value of 0.896. Using these predicted parameters, the experimental results obtained were BT?=?7.0?±?0.10 min, CD?=?162.0?±?2.0 mm, CW?=?45.0?±?1.0 mm and CH?=?44.50?±?2.00 N.     

Development of a Chocolate Flavored Peanut Beverage

Nine chocolate-flavored peanut beverages (CFPB) were prepared using peanut protein isolate as source of protein and analyzed for physical-microbiological-sensory qualities. The quality attributes such as color, aroma, viscosity, and flavor of CFPB were similar to that of commercial chocolate milk. The total aerobic populations of the beverage before and after refrigeration for 7 days were less than 10 and 200 colonies/g, respectively, and no coliform bacteria was detected in this product. Sensory evaluation and response surface methodology indicated that optimum formulation of CFPB was obtained by using 3.5% protein (from peanut protein isolate), 3.5% butter, 8% sugar, 0.7% cocoa powder, 0.1% stabilizer, and water. Consumer study of the CFPB revealed that all sensory characteristics were acceptable in the range of like to extremely like.     

大杏仁夹心香肠夹心馅料调配

研究大杏仁夹心香肠馅料的较优配方.筛选适宜的调味酱,摸索大杏仁、花生酱、水淀粉和糖对夹心馅料感官的影响,通过正交试验得到较优配方.本实验筛选出花生酱与大杏仁进行调配,研究得到较优馅料配方为大杏仁29g、花生酱39g、水淀粉22g、糖10g.产品肉馅呈红色,夹心呈棕黄色,色泽搭配诱人,具有良好的切片性,具有明显的大杏仁香...     

A study on parameters of potential cocoa butter analogue synthesis from camel hump by lipase-catalysed interesterification in supercritical CO2 using response surface methodology

A potential cocoa butter analogue was prepared from camel hump fat and tristearin by enzymatic interesterification in supercritical carbon dioxide (SC–CO₂) using immobilised Thermomyces lanuginosus lipase (Lipozyme TL IM) as a biocatalyst. Response surface methodology (RSM) was used to investigate the effects of pressure, temperature, tristearin/camel hump fat ratio, water content, and incubation time on TAG distribution of cocoa butter analogue. The process conditions were optimised by conducting experiments at five different levels. A second order polynomial response surface equation was developed to indicate the effect of variables on TAG distribution of cocoa butter analogue. Overlaid contour plots generated using the response surface equations showed that all TAG components of cocoa butter analogue are significantly affected by the experimental independent variables. The pressure of 10 MPa; temperature of 42 °C; SSS/CHF ratio of 1.15:1; water content of 10% (w/w); and incubation time of 3 h were found to be the optimum conditions to achieve the most similar cocoa butter analogue to the corresponding cocoa butter.     

明胶/普鲁兰酶改性淀粉膜的制备与性能研究

研究了普鲁兰酶对淀粉膜性能的影响及明胶对普鲁兰酶改性淀粉膜性能的影响。结果表明:与原淀粉膜相比,普鲁兰酶改性淀粉膜的表面更平滑;膜的热稳定性增大,热封性能增强;抗拉强度、水蒸气透过率和透光率分别增加了75%、18%和35%,断裂伸长率降低了53%。与未添加明胶的酶改性淀粉膜相比,添加明胶后,膜的表面变粗糙;膜的阻水性能与阻光性能增强,热封性能变差。当明胶添加量为10%时,膜的抗拉强度增加了17.6%;当明胶添加量为25%时,膜的断裂伸长率增加了54.3%;在明胶添加量为15%时,膜的热稳定性最大。     

Effect of nut oil migration on polymorphic transformation in a model system

Fat migration in confectionery products can lead to significant deterioration in quality. This occurs not only through loss in texture contrast between chocolate and filling but also through the appearance of fat bloom on the surface of the chocolate. This latter aspect is often, although not exclusively, linked to the transformation of the cocoa butter β_V phase into β_VI. In this study, the influence of hazelnut oil on the polymorphic transformation of cocoa butter has been determined, showing that even small additions (1%) of nut oil can have a significant impact on the rate of transformation. Additionally, use of a model system has shown that polymorphic transformation in cocoa butter is linked to the degree of migration of nut oil from a filling. Portions of the cocoa butter close to the filling experience both greater degrees of migration and faster transformation.     

Cookie- Versus Cracker-Baking—What's the Difference? Flour Functionality Requirements Explored by SRC and Alveography

The many differences between cookie- and cracker-baking are discussed and described in terms of the functionality, and functional requirements, of the major biscuit ingredients—flour and sugar. Both types of products are similar in their major ingredients, but different in their formulas and processes. One of the most important and consequential differences between traditional cracker and cookie formulas is sugar (i.e., sucrose) concentration: usually lower than 30% in a typical cracker formula and higher than 30% in a typical cookie formula. Gluten development is facilitated in lower-sugar cracker doughs during mixing and sheeting; this is a critical factor linked to baked-cracker quality. Therefore, soft wheat flours with greater gluten quality and strength are typically preferred for cracker production. In contrast, the concentrated aqueous sugar solutions existing in high-sugar cookie doughs generally act as an antiplasticizer, compared with water alone, so gluten development during dough mixing and starch gelatinization/pasting during baking are delayed or prevented in most cookie systems. Traditional cookies and crackers are low-moisture baked goods, which are desirably made from flours with low water absorption [low water-holding capacity (WHC)], and low levels of damaged starch and water-soluble pentosans (i.e., water-accessible arabinoxylans). Rheological (e.g., alveography) and baking tests are often used to evaluate flour quality for baked-goods applications, but the solvent retention capacity (SRC) method (AACC 56-11) is a better diagnostic tool for predicting the functional contribution of each individual flour functional component, as well as the overall functionality of flours for cookie- and/or cracker-baking.     

Predicting the cookie quality of flours by using Mixolab<Superscript>®</Superscript>

The objective of this study was to determine the possibility of using Mixolab^® to predict the cookie baking quality of different wheat flours. Mixolab data was also compared with various flour quality characteristics. There were significant correlations (P < 0.001) between Mixolab stability and some of the flour quality characteristics (protein and wet gluten contents, Zeleny sedimentation value). Alveoconsistograph T value was negatively correlated with Mixolab C3, C4 and C5 values. The cookie diameter gave highly significant correlations with protein content, Zeleny sedimentation value and damaged starch content. Mixolab C3 and C4 values were highly correlated (P < 0.001) with both cookie diameter and spread ratio. A significant correlation coefficient (r = 0.556) was determined between the cookie diameter and C1–C2 value which is an indication of protein quality. The dependence of cookie diameter and spread ratio on Mixolab C3 value, damaged starch content and Zeleny sedimentation value were analyzed with multiple regression analysis and high multiple correlation coefficients were found between these parameters (r = 0.948 and 0.861, respectively).     

Starch–lipid composites containing cinnamaldehyde

The formulation of a starch–lipid composite containing cinnamaldehyde as antimicrobial agent has been studied. Cinnamaldehyde was incorporated as an emulsion using acetem 90–50 K as a carrier and Tween 60 as the emulsifier. Oil in water emulsions were prepared by direct emulsification using a high shear mixer or a high pressure homogenizer (Microfluidizer). Oil in water emulsions containing cinnamaldehyde were further used to prepare starch–oil composites by mixing the emulsions with a completely gelatinized starch solution (wx starch, native corn dent starch, and high AM corn starch). Results demonstrated that in the presence of the emulsifier Tween 60, stable composites could be obtained when sufficient amount of AM was present in the sample. Finally, stable composites were tested for their biocidal activity against Listeria monocitogenes; no survivors remained after 1 day of incubation with 0.25% cinnamaldehyde or after 7 days with 0.025% cinnamaldehyde.