Physico-chemical characteristics of white suger fractions separated by crystal sizes

According to the EU Council Directive 2001/111/EC, related to certain sugars intended for human consumption, a great attention is paid to color in sugar. On the other hand, the non-sucrose compounds having intensive color tend to build into the sucrose crystals. Since Serbia has to work on the new rules concerned sugar quality and harmonization with EU standards, some investigations on sugar crystals are carried out at the request of some sugar factories. Investigations are carried out on sugar crystal size dependence on sugar color and on dissolution rate of different sugar crystal size fractions with the aim to create new sugar products. In this study, sugar samples with different sugar color are divided into 5 fractions by crystal size, defining size distributions. In each fraction the color in solution and the type of color are measured, as well as other relevant physico-chemical parameters. The conclusion is that the sugar color type depends on the crystal size, but sugar crystal solution is not dependent on crystal size except a fraction smaller than 200 µm, which has 30-75% higher sugar color in solution than the other crystal size fractions

Analysis of the influence and optimization of concentration of organic acids on chemical and physical properties of wheat dough using a response surface methodology and desirability function

In order to improve physical and chemical properties of dough produced from wheat flour of suboptimal quality (protein content 10.7% dry basis, dough energy 4.0 cm2), optimal doses of ascorbic and citric acid were evaluated using a response surface methodology and desirability function. The paper brings the analysis of the main effects as well as their interactions. The effect of organic acids was evident in relation to pH lowering and decrease in free thiol groups, which consequently changed the physical properties of dough (increased dough energy, extensibility and resistance). The well known oxidative effect of ascorbic acid which is manifested as increase in dough energy and resistance, was enhanced by the addition of citric acid i.e. their synergistic action. Contribution of citric acid was the donation of hydrogen ions which changed the pH, lowered the content of free -SH groups and increased protein aggregation. Ascorbic acid individually significantly increased energy (linear regression coefficient b1 = 4.010-4) but higher effect was exerted by the addition of ascorbic and citric acid mixture as seen through higher interaction regression coefficient (b12 = 0.076). Dough resistance was significantly affected only by ascorbic acid due to its oxidizing action whereas dough extensibility was affected by both acids (main effects) at all applied doses and their mixtures. The effect on dough extensibility depends on the dose of acids but resistance decreased with quadratic increase of acid doses. Second-order polynomials were used in modeling of responses (dough energy, resistance and extensibility) which showed a good fit with experimental data as shown by high values of the coefficients of determination R2 for energy, resistance and extensibility (0.953, 0.976 and 0.996, respectively). Based on F value, it could be concluded that the model gave good prediction of experimental data while p-values for all responses showed that the models were significant at significance of 90%. The obtained models were used to optimize the doses of ascorbic and citric acid in order to maximize dough energy and extensibility. Significant increase of dough energy by 4.7 times and extensibility by 1.5 times was achieved by the set of optimum conditions of 97 mg/kg citric and 100 mg/kg ascorbic acid. The obtained results are applicable in semi-industrial and industrial facilities for flour processing

The impact of the manufacturing process on the hardness and sensory properties of milk chocolate

The aim of this paper was to examine the impact of the manufacturing process on the textural characteristics and sensory properties of milk chocolate. The research was conducted on the samples of chocolate produced in a ball mill during 30, 60 and 90 minutes of refining, each of them being pre-crystallized at 26, 28 and 30°C. A chocolate mass of identical ingredient composition was also produced using a standard manufacturing process at the same pre-crystallization temperatures. Chocolate hardness was examined using a piece of equipment called Texture Analyser, measuring the stress intensity which leads to chocolate crushing. Sensory analysis was performed using the point scoring method. The new manufacturing process, i.e. the manufacturing of chocolate in a ball mill improves sensory properties and hardness of milk chocolate. [Projekat Ministarstva nauke Republike Srbije, br. TR 31014

Influence of the operating parameters on the flux during microfiltration of the steepwater in the starch industry

The subject of the work is the possibility of applying microfiltration through a ceramic tubular membrane with 100 nm pore sizes to the steepwater obtained in the production process of corn starch. The dry matter content should be reduced in the steepwater permeate. Thus the consumption of the process water would be reduced, the nutrients from the steepwater could be exploited as feed and the wastewater problem would consequently be solved. The objective of the work was to examine the influence of the operating parameters on the permeate flux during steepwater microfiltration. The parameters that vary in the course of microfiltration, were the transmembrane pressur and flow rate, while the permeate flux and dry matter content of the permeate and retentate were the dependent parameters, constantly monitored during the process. Another objective of this study was to investigate the influence of static turbulence promoter on the permeate flux during steepwater microfiltration. Static mixers enhance permeate flux, thus the microfiltration can be performed longer. As a result of the statistical analysis, the optimal conditions for steepwater microfiltration were determined. The maximum value of the permeate flux without mixer (25 lm-2h-1) was achieved at a pressure of 2 bars and a flow rate around 100 lh-1. With the use of static mixer the flux is 2,5 times higher compared to the one obtained without the mixer. The dry matter content of the permeat after 2.5 hours of mucrofiltration was lowered by 40%

Quality improvement of gluten-free bread based on soybean and enriched with sugar beet molasses

The aim of this work was to improve the quality of gluten-free bread made with high content of soy flour and enriched with sugar beet molasses by incorporating ingredients with a potential to simultaneously enhance the nutritional quality of the breads. The following ingredients were used: pea protein isolate, pea fibre and chia seeds. The chosen ingredients exerted positive effects on bread quality. They promoted volume increase and crumb softening. In this respect, the most effective ingredients were pea protein isolate (at 1% supplementation level), pea fibre (at up to 2% supplementation level) and chia seeds (at 1% supplementation level). The sensory analysis revealed that pea fibre and chia addition at 1 and 2% supplementation level provided bread with higher scores regarding overall acceptance, crumb texture and taste. At 1% supplementation level, there was not found statistically significant difference in sensory attributes of bread supplemented with pea protein isolate in comparison to the control. However, pea protein isolate was found to strongly diminish bread taste at 4% supplementation level due to presence of beany taste

The influence of the extraction parameters on the quality of dried sugar beet pulp

Growing demand for better quality and cheaper products put on the need to industry to balance between the two kinds of needs, which are the reduction of production costs and to ensure a high quality product. This is the case with dried sugar beet pulp as a byproduct of sugar refining process. One of the possibilities to reduce energy consumption is savings in the process of thermal dehydration in the process of the conventional drying of pulp. Pulp drying is one third of total energy consumption in the sugar factory. Acidification of water extraction result in pulp that could be pressed better and in other hand in the juice with less non-sucrose compounds. Keeping the extraction process under certain conditions, directly affects on the quality of the extracted pulp and on effects of their further processing. This paper examines the impact of the extraction parameters of sugar from sugar beet and agents of acidification for water extraction (sulphurous acid, hydrogen peroxide) on the quality of dried sugar beet pulp. Extraction of sugar from sugar beet cossettes by hydrogen peroxide at pH 5.5 to 8.5 does not cause changes in mechanical properties of sugar beet cossettes and in water retention coefficient, but increases the brightness of dried sugar beet pulp for about 5-7 units, which solubility in water does not depend on the applied concentration of extracting agents, but increases in dependence on the duration of the extraction. Sugar beet pulp extracted at pH 11.0 has reduced strength, they are highly hydrated, and under the force they lose their shape, binding a larger amount of water thus reducing the effect of their pressing. The changes in microstructure were probably accompanied by segmenting the linear parts of macromolecules and are reflected in the increase of water retention capacity and increase the solubility of dried sugar beet pulp for two to three times. Under the same conditions of extraction, sulphurous acid produces similar but relatively mild changes in the characteristics of extracted and dried sugar beet pulp compared to conditions when hydrogen peroxide is used. From the point of the quality of the product of extraction, the most favorable results are obtained when the extraction is carried on at pH 5.5 for a period of 1 h at 70 °C, using water for extraction with sulphourus acid with the addition of 5% hydrogen peroxide. Under these conditions no significant degradation of sugar beet tissue is detected, do not change the physical, chemical and mechanical properties of the extracted pulp. But there is an average increase of lightness of dried noodles for about 7 units, which represents a significant improvement of their quality, since there is difficult to sell on the market the dried sugar beet pulp with increased colour