Determination of the process effect on cocoa butter crystallization by rheometer: Kinetic modeling by Gompertz equation.

In this study, the effects of temperature (22, 24, 26, 28, and 30°C) and strain (0.1%, 1%, and 5%) on cocoa butter (CB) crystallization were investigated by oscillatory test, and the four-parameter Gompertz model was used to interpret the effect of parameters on pre-crystallization, nucleation, and crystal growth stages of CB. Lag time and growth rate were calculated using the Gompertz model using time-dependent storage modulus (G') data. According to the results, CB crystallization at 26°C with a 1% strain value had the highest growth rate value, the shortest lag time, and the formation of ßv polymorph type. Followingly, polymorphic types of the CB crystals were determined based on the melting points of polymorphs via the temperature ramp step, and the results obtained were correlated with a polarized light microscope. In conclusion, using a rheometer in both the observation of the pre-crystallization process and the determination of polymorph types is very important for research and development studies in the chocolate industry for process and formulation optimization. PRACTICAL APPLICATION: This study demonstrates the feasibility of a novel approach for investigating crystallization and oscillatory shear of CB using a rheometer, both for observing crystallization kinetics and determining polymorph type, accompanied by the Gompertz equation to model the crystallization kinetics. According to the results, the effect of process parameters (temperature and shear) on the crystallization behavior of CB can be observed by rheometer, which can provide a detailed perspective for chocolate manufacturers and researchers in research and development studies.

Influence of process conditions of alkalization on quality of cocoa powder.

In this study, the effects of independent variables such as alkaline (NaOH) salt concentration (3.0-6.0 g/100 mL), alkalization temperature (60-90 °C), and time (20-40 min) on cocoa powder (low-fat) properties were investigated by using Central Composite Design. The physicochemical and color properties of samples, powder characteristics, volatile component profile, total polyphenol content (TPC), as well as antioxidant activity potentials using different methods (DPPH and ABTS) were determined. Significant models were identified for the effects on major alkalization indicators (L*, a*/b*, pH), as well as TPC and antioxidant activity potential (DPPH), which are the main motivators for the preference and consumption of cocoa products (p < 0.05). The established model was validated, and their predicted values were found to be very close to real results. It was determined that the alkali concentration had a more significant effect on dependent variables, especially on alkalization indicators, compared to the other independent variables. Furthermore, strong correlations were determined between TPC and antioxidant activity potential and color properties (L*, a*, b*, and a*/b*). Optimum concentration, temperature and time were found to be 5.3 %, 84 °C and 35.7 min for maximizing a*/b* value. The establishment of such models lead to optimizing process conditions of alkalization with minimum effort and labor force for obtaining cocoa powder with desired quality depending on the usage purpose.

Carnauba wax and adipic acid oleogels as an innovative strategy for cocoa butter alternatives in chocolate spreads.

The aim of this study was to replace cocoa butter substitute (CBS) with structured sunflower oil in chocolate spread partially. Two types of oleogel, 6% carnauba wax (CWO) and 2% carnauba wax with 4% adipic acid (AD-CWO) were substituted (at 20%, 50%, and 70%), and chocolate spread characteristics were evaluated. Various properties of chocolate spread samples were investigated as peroxide value, firmness, oil binding capacity, moisture content, molecular interactions, and molecular conformation of fat crystals. The increasement of CBS substitution by oleogel in samples significantly reduced firmness. The samples with 20% replacement formulated by CWO and AD-CWO had the highest oil binding capacity, 97.48 ± 0.21% and 97.73 ± 0.02, respectively. Moreover, oxidative stability analysis showed a positive correlation with an increasing replacement level over 90 days of storage. Based on FT-IR analysis, the new intermolecular hydrogen bond formation in the oleogel-based spreads network has been confirmed. CBS replacement with oleogels revealed the presence of stable ß´ polymorphs with low intensity. In conclusion, the carnauba-based oleogels have significant potential to substitute CBS in chocolate spread partially.

Effects of gelatin concentration, adding temperature and mixing rate on texture and quality characteristics of model gels.

In this study, the effects of gelatin concentrations (GC) (5.0-10.0 g/100 g), mixing rate (MR) (100-1100 rpm), and gelatin addition temperature (GAT) (55, 60, and 65°C) were investigated on the main textural and various physicochemical properties of model gels (n = 72) prepared using sucrose and glucose syrup (40-42 DE). Considering the p-value of the F-statistic calculated by analysis of variance and the 5% significance level, the production parameters and their interactions had a significant effect on the quality parameters. The influence of the production parameters GC, MR, and GAT, and the interaction of these parameters, GC * MR, GC * GAT, MR * GAT, and GC * MR * GAT of the model gels on the quality characteristic were expressed by converting the Type III SS values into percent values. When all quality characteristics were considered together, MR was the most influential with a score of 58%. PCAmix, a combination of factorial analysis with PCA, was used to visualize the correlations between the production parameters and the quality characteristics of the modeled gels. A great influence was observed between MR and moisture content, color properties, and texture parameters, except springiness. A moderate effect of GC and a minor effect of GAT could be characterized. With the 2D-map of observations, the model gels could be clearly divided into two groups according to the MRs. In accordance with the observations diagram of PCAmix, the similarity dendrogram of AHC also formed two clusters, one cluster for the samples with MR 100 and 200 rpm and one cluster for the samples with MR 500 and 1100 rpm.

Cocoa polyphenols and milk proteins: covalent and non-covalent interactions, chocolate process and effects on potential polyphenol bioaccesibility.

In this study, we discussed covalent and non-covalent reactions between cocoa polyphenols and proteins (milk and cocoa) and the possible effects of these reactions on their bioaccessibility, considering environmental and processing conditions. Better insight into these interactions is crucial for understanding the biological effects of polyphenols, developing nutritional strategies, and improving food processing and storage. Protein-polyphenol reactions affect the properties of the final product and can lead to the formation of various precursors at various stages in the manufacturing process, such as fermentation, roasting, alkalization, and conching. Due to the complex composition of the chocolate and the various technological processes, comprehensive food profiling strategies should be applied to analyze protein-polyphenol covalent reactions covering a wide range of potential reaction products. This will help to identify potential effects on the bioaccessibility of bioactive compounds such as low-molecular-weight peptides and polyphenols. To achieve this, databases of potential reaction products and their binding sites can be generated, and the effects of various process conditions on related parameters can be investigated. This would then allow to a deeper insight into mechanisms behind protein-polyphenol interactions in chocolate, and develop strategies to optimize chocolate production for improved nutritional and sensory properties.

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.

A model study on the site-specificity of (-)-epicatechin-induced reactions in ß-lactoglobulin by high-resolution mass spectrometry in combination with bioinformatics.

Polyphenol-protein reactions in model solutions of ß-lactoglobulin (ß-LG) incubated with (-)-epicatechin at 37 °C and 60 °C were monitored by microLC-timsTOF Pro-MS/MS combined with bioinformatics strategies. The addition of (-)-epicatechin to the model solutions resulted in changes in tryptic peptide profiles. Covalent bond formation between (-)-epicatechin o-quinones and ß-LG was identified for the residues S27, S30, K60, C66, K69, and C160, with C160 being the predominant binding site. Furthermore, the incubation of ß-LG with (-)-epicatechin significantly promoted oxidation, especially for the residues M7 and M24. The reaction of monomeric (-)-epicatechino-quinone at C160 was also identified in the milk chocolate sample. The adaptation of this study by extending the scope of the reaction products offers significant potential for comprehensive food profiling strategies.

Formulating and studying compound chocolate with adding dried grape pomace as a bulking agent.

The use of dried grape pomace (DGP) as a bulking agent for partly substitution of sugar, milk powder and whey powder in compound chocolate (CC) was investigated. D-optimal mixture design was used to determine the effect of composition on the particle size, flow behaviour (Casson yield value and plastic viscosity), as well as total phenolic and resveratrol contents before and after in vitro digestion. The various models (linear, quadratic and cubic) which were identified as significant (P < 0.05) were used in this study. As a result, DGP was found suitable to be used in CC as a bulking agent to partially substitute sucrose, milk powder and whey powder to increase functional properties and decrease the cost of the CC. For CC with the most acceptable rheological properties and a satisfactory level of TPC and resveratrol, optimum usage levels of DGP were identified as 7.1% to 10.0%. Further studies will require to modify flow behaviours by optimizing the particle size of pomace.

Soft confectionery products: Quality parameters, interactions with processing and ingredients.

The motivation in the preference of confectionery products consists of the perception formed during the purchase and consumption. This perception is a direct determining factor in the repeated purchasing behavior of the consumer. Also, the products must meet consumer demands. For this reason, it is very important to understand the confectionery quality characteristics, the factors affecting them, and their interaction with each other. In this context, the effects of major and minor components used in innovative soft confectionery products on quality should be considered first. As with all other foods, new ingredient(s) incorporated into the formulation and processing changes have significant effects on the quality characteristics of soft confectionery products. Therefore, in this review study, after giving information about soft confectionery products and their quality characteristics, the interactions of especially innovative components and processes that have important effects on these foods were discussed in detail.

Effect of Various Bulk Sweeteners on the Survivability of Lactobacillus casei 431 in Milk Chocolate: Rheological and Sensory Properties Analysis.

BACKGROUND: Probiotics are the most widely consumed functional food. Consumers demand the production of foods also in low-calorie forms. OBJECTIVE: In this study, Lactobacillus casei 431 and various sweeteners were used in milk chocolate as probiotic and bulking agents, respectively. METHODS: Samples were prepared by using sucrose or optimum polyols combination. Chocolate samples were stored at two temperatures (4°C and 20°C) for 180 days and the viability of probiotic cells was controlled with the purpose of specifying the presented storage temperature. RESULTS: The highest probiotic viability was determined in the samples produced with sucrose and stored at 4°C. The cell counts were retained at the functional amount after maintenance for 6 months. Probiotic sucrose-free chocolate was more viscous than control chocolate, although displayed satisfactory sensory attributes. CONCLUSION: As a result, the sugared and sugar-free probiotic milk chocolates could be stored at room temperature. Due to the acceptable number of probiotic cells, the sucrose-free chocolates containing probiotics were considered as functional foods.

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 ßV 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.

Effects of polyols on the quality characteristics of sucrose-free milk chocolate produced in a ball mill.

Sucrose-free milk chocolates containing different types of bulk (isomalt, xylitol and maltitol) and high intensity (Stevia) sweeteners were produced by using a ball mill. The main quality characteristics of the formulated chocolates were evaluated and compared with those of the conventional sample containing sucrose. The Casson model was the best fitting model for the rheological data. Casson viscosity and Casson yield stress were significantly affected by the type of bulking agent in chocolates formulated with xylitol (p < 0.05). However xylitol notably improved the overall acceptability according to the sensory analysis results. Chocolates containing the sucrose replacers demonstrated lower T onset values and higher enthalpy than the control sample. Sucrose-free chocolates illustrated a higher degree of particle agglomeration. Bulk sweeteners meanwhile seem to have high potential for milk chocolate production with low calorie values by using the ball mill technique. Industrial applications: the production of sucrose-free chocolates with conventional methods requires a lot of time and energy. Recently, using alternative methods for chocolate production has been raising interest in many small industries. This study proposed a ball mill method for the preparation of sucrose-free milk chocolates with physiochemical properties almost ranging in the standard limit defined for chocolate. Although using the ball mill method presents a more cost-effective technique for chocolate production and provides shorter processing times for small chocolate industries, it seems to be less efficient in evaporating moisture than the conventional processing. Challenges are still ahead for upgrading this alternative technique to be efficient in evaporating more moisture during operation ending in a high quality product.

Formulation of dark chocolate as a carrier to deliver eicosapentaenoic and docosahexaenoic acids: Effects on product quality.

In this study, dark chocolate enriched with EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) was developed using various forms and origins. Quality characteristics such as physical, thermo-gravimetric, rheological, textural and sensory properties of chocolates were investigated. The highest EPA/DHA stability was determined in samples prepared by free-flowing powder and microencapsulated forms of omega-3 fatty acids (FA). The L∗ and C∗ values varied from 32.16-33.37 and 7.45-8.09, respectively for the all samples. Hardness values ranged between 6422 and 8367 N and the use of EPA/DHA in the triglyceride form caused softer chocolate whereas control sample was the hardest sample. Melting and rheological properties were not significantly affected by the studied EPA/DHA sources (P < 0.05). Microencapsulated EPA/DHA added chocolate was the most preferred source whereas sample with algae oil showed the lowest acceptability. According to the results, dark chocolate can be used for delivering omega-3 FA by considering their origin and physical form.

Oleogels, a promising structured oil for decreasing saturated fatty acid concentrations: Production and food-based applications.

Oils and fats are widely used in the food formulations in order to improve nutritional and some quality characteristics of food products. Solid fats produced from oils by hydrogenization, interesterification, and fractionation processes are widely used in different foodstuffs for these aims. In recent years, consumer awareness of relation between diet and health has increased which can cause worry about solid fat including products in terms of their high saturated fatty acid and trans fatty acid contents. Therefore, different attempts have been carried out to find alternative ways to produce solid fat with low saturated fatty acid content. One of the promising ways is using oleogels, structuring oils with oleogelators. In this review, history, raw materials and production methods of the oleogels and their functions in oleogel quality were mentioned. Moreover, studies related with oleogel usage in different products were summarized and positive and negative aspects of oleogel were also mentioned. Considering the results of the related studies, it can be concluded that oleogels can be used in the formulation of bakery products, breakfast spreads, margarines, chocolates and chocolate-derived products and some of the meat products.

Influence of calcium fortification on physical and rheological properties of sucrose-free prebiotic milk chocolates containing inulin and maltitol.

In the present study, chocolates were investigated that had been prepared according to the composition specified as a result of this previous work (9.00 % w/w inulin and 34.0 % w/w maltitol) Certain physical (particle size distribution [PSD], brightness, chroma, water activity and hardness) and rheological features of the samples resulting from the addition of calcium carbonate in different quantities (300, 450, 600, 750 and 900 mg calcium carbonate to 100 mg milk chocolate) were studied. Both the Herschel-Bulkley and Casson models were used to investigate the rheological findings. It was determined by comparing certain rheological (rate index, Casson yield stress and Casson viscosity) and physical (chroma and hardness) parameters that samples containing 409.5 mg calcium (nearly 41.0 % of the RDA of calcium) per 100 g chocolate did not show significant differences from samples from the control group. Furthermore, these calcium-containing samples were shown to exhibit positive differences in other physical properties (brightness and water activity) that could be noteworthy and significant with respect to visual quality and shelf life.