Rapid tempering of sucrose-free milk chocolates by β V seeding: textural, rheological and melting properties

Engineering effect of oleogels with different structuring mechanisms on the crystallization behavior of cocoa butter

As promising cocoa butter (CB) alternatives, oleogels have the potential to prevent fat blooms of chocolate. We aimed to explore possible reasons for the bloom resistance of oleogels by investigating the crystallization behavior of CB-oleogel blends, including crystallization kinetics, thermodynamic properties, crystal polymorphism, and oil distribution. Oleogels structured by monoglyceric stearate (MO), β-sitosterol/lecithin (SLO), and ethylcellulose (EO) were selected as representative oleogels with various structuring-mechanisms. Crystallization kinetic results showed that the crystallization dimension of CB-oleogel increased with the oleogel proportion (from one-dimensional to multi-dimensional), confirming that CB crystallization was inhibited. The presence of liquid oil and oleogelators in oleogels may increase the free energy barrier for CB crystallization. The proton mobility of liquid oil in CB-MO was lower because MO was more tightly bound to CB. The crystallization mechanism of the CB-oleogel suggested that the inhibitory effect of oleogels on CB crystallization delayed the polymorphic transition, thereby improving the bloom stability of chocolate.

Chocolate flow behavior: Composition and process effects

Chocolate is a non-Newtonian substance, and such substance has different viscosities at different shear rates. Rheological evaluations have become indispensable instruments for characterizing final chocolate, forecasting product efficiency and consumer acceptance. During production, the different steps depend on a well-defined viscosity and yield stress. Furthermore, the characteristics of the final chocolate (the surface and mouth-feel) are directly related to the chocolate's viscous behavior. There is a demand for better understanding the variables affecting chocolates flow behavior. Current research realized great insight into the chocolate flow behavior in different processes such as refining, conching, and tempering. Also, the influence of formulation and particle characteristics on flow behavior of the intermediate product and the final product were discussed. Each stage of the production process: mixing, refining, conching and tempering involves modifications of macroscopic characteristics of the chocolate ingredients thus affecting the rheological attributes of the final product. Particle size distribution and ingredient composition play substantial roles in shaping its flow behavior and sensory perception. The rheological properties of chocolate provide substantial information for food scientists to improve and optimize their products and manufacturing processes. Nowadays, a thorough understanding of chocolate flow behavior is a necessity for food scientists and industry.

Sugar-Free Milk Chocolate as a Carrier of Omega-3 Polyunsaturated Fatty Acids and Probiotics: A Potential Functional Food for the Diabetic Population

Chocolate is an adequate matrix to deliver bioactive ingredients. However, it contains high sugar levels, one of the leading causes of chronic degenerative diseases. This work aimed to evaluate the effects of milk chocolate reformulation with alternative sugar sweeteners (Sw; isomalt + stevia), probiotics (Prob), and ω-3 polyunsaturated fatty acids (PUFAs) on its physicochemical properties and consumers' acceptability. Lactobacillus plantarum 299v (L. p299v) and Lactobacillus acidophilus La3 (DSMZ 17742) were added as Prob strains, and fish oil (FO) was added as the source of ω-3 PUFAs. Prob addition resulted in chocolates with >2 × 107 colony forming unit (CFU) per serving size (12 g). Except for Prob, aw values of all treatments were <0.46. Sw and Sw + Prob presented the nearest values to the control in hardness, whereas Sw without FO increased fracturability. FO, Sw + FO, and Sw + Prob + FO contained 107.4 ± 12.84, 142.9 ± 17.9, and 133.78 ± 8.76 mg of ω-3 PUFAs per chocolate, respectively. Prob + FO increased the resistance of chocolate to shear stress, while Sw + FO showed a similar flow behavior to the control. The consumers' acceptability of Sw + Prob chocolate was adequate, while Sw + Prob + FO had higher acceptability than Prob + FO. Health benefits of reformulated milk chocolates requires further assessment by in vitro, in vivo and clinical studies.

Pre-crystallization process in chocolate: Mechanism, importance and novel aspects

Pre-crystallization is an important step in the production of chocolate, which is defined as tempering of cocoa butter through primary and secondary nucleation. The goal of tempering is to obtain a sufficient amount of β_V polymorph of the right size. The pre-crystallization process has a great impact on the quality and production cost of final product. Development of chocolate technology requires the use of the most appropriate techniques and ingredients without negatively affecting the quality characteristics. Applications of novel technologies within the confectionery industry have allowed production of chocolate in sufficient quantities to meet the public needs. In order to provide and investigate the potential and usage of novel technologies, the present review focused on different pre-crystallization methods and factors affecting the processing conditions. Seeding and ultrasound-assisted pre-crystallization can be used as alternatives to conventional tempering process. However, in both methods, optimization of experimental conditions is required.

Alternative Tempering of Sugar-Free Dark Chocolates by βv Seeding: Sensorial, Micro-Structural and Some Physical Properties and Volatile Profile

In this study, sugar-free dark chocolate was produced from isomalt and maltitol by βV seeding technique as an alternative to conventional tempering process. The effect of βV seed concentrations on the particle size distribution, textural, rheological and melting properties of the end products was studied, and the results were compared with those of conventional sugar-free dark chocolates. For this aim, conched dark chocolates were melted and crystallized with βV seeds added at different concentrations (0.5, 0.6, 0.7, 0.8, 0.9 and 1.0 %, m/m). Conventional tempering process was performed by using temper machine (47–27–32 °C). Brightness, chroma, whiteness index and tetramethyl pyrazine content (as marker compounds of dark chocolate volatile compound) were not influenced by seeding technique compared to conventional tempering method. The water activity of the dark chocolate samples was substantially affected by βV seed level according to used bulk sweetener. However, all the values were determined below 0.4 which is critical limit for chocolate. Regarding overall acceptability, sugar-free dark chocolates tempered by βv seeds had very close scores compared with conventional one, implying that sugar-free chocolates can be produced by βv crystals with desired quality characteristics similar to conventional samples. Results of this study showed that it is possible to produce sucrose-free dark chocolates by using βV seeds with desired quality similar to chocolate produced by using conventional tempering.

The optimization of prebiotic sucrose-free mango nectar by response surface methodology: The effect of stevia and inulin on physicochemical and rheological properties

The reduction of sugar consumption is one of the major challenges for nutritionists and food industry. Therefore, it is significant to replace sucrose with other types of sweeteners, especially, natural ones. The aim of the present study is to produce low-calorie, sucrose-free mango nectar and to optimize the formulation by employing response surface methodology. The two independent variables were stevia, as a low-calorie sugar replacer (0, 1.5, and 3% w/w) and inulin as a prebiotic texturizer (0, 3, and 6% w/w) in order to compensate sugar elimination defect on viscosity and °Brix. The fitted models indicated a high coefficient of determination. The results revealed that stevia and inulin are as the independent variables which had significant effects on °Brix, viscosity, and sensory scores (p < 0.05). Also, pH was affected by stevia concentration. The rheological behavior of the sucrose-free mango nectar was non-Newtonian, shear thinning as Herschel–Bulkley model which was not different from the reported behavior for normal mango nectar-containing sucrose. The optimization of the variables, based on the response surface three-dimensional plots, demonstrated that utilizing 6% w/w inulin and 3% w/w stevia produced the optimum mango nectar with the desirability of 0.85 without undesirable changes in the physicochemical and organoleptic properties. The optimum sample was produced in triplicate to validate the optimum model as well.