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The microencapsulation of essential oils can provide their evaporation and oxidation protection, flavor retention or/and masking of unpleasant taste. The microencapsulation process involves emulsions preparation and drying of the obtained emulsion droplets. The aim of this study is the determination of optimal conditions for preparation of the stable O/W emulsions containing juniper berry essential oil with minimal droplet size, as a preparatory stage for microcapsule formation. As the first step for pre-emulsions preparation, homogenization at 10000 rpm for 5 min. was chosen, which gave emulsions with droplet size between 1.82 and 2.51μm, depending on concentrations of the surfactant (Tween 20) and encapsulated essential oil. The second step was ultrasound emulsification during 5 minutes at a frequency of 99%, using pulsed 10:10 s (ON/OFF) ultrasound treatment, which was chosen as an optimal, creating emulsions of droplet sizes of 320 nm in diameter (for 5% essential oil and 1% Tween 20). The addition of wall material changed the size and stability of emulsions, which depends on type of biopolymer and its surface competition with used surfactant. The maltodextrin (MD), gum arabic (GA) and their mixture in equal ratio were used. GA emulsions can be singled out as the most stable without used surfactant, with D4,3 = 1.11 ± 0.003 μm. Using MD as a wall material requires addition of surfactant (1% w/v) to form stable emulsions. The mixture of MD/GA can be used with or without surfactant. The addition of Tween 20 (1% w/v) decreases droplet size from 14.86 to 0.99 μm, while utilization of the ultrasound contributes to the droplet size decrease and emulsions stability. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 46010]

Apple pomace, a by-product that remains after extraction of juice from fruit, is a good source of dietary fibre, minerals and different phytochemicals such as phenolic acids. Although the valorization of apple pomace as a bakery ingredient was performed by several authors, there is a lack of information on attempts of incorporation of apple by-products in the form of coextrudates with corn grits (CAPCG). In this study, sponge cakes were created with apple pomace coextruded with corn grits in the ratio of 45:55 by partial replacing wheat flour with coextrudate in the formulation at 10%, 20% and 30% level. With the increase in the proportion of coextruded particles, the farinographic characteristics of dough samples showed an increase in water absorption and dough development time due to larger particles of coextrudates, and loss of dough elasticity. Consequently, the cake specific volume decreased over the range between 3.6 - 14.2%, but only the substitution level of 30% yielded an increase in cake firmness after 1 h of cooling and after 24 h of storage. The estimation of sponge cake sensory properties using the hedonic scale from 1 to 9 showed that the most acceptable texture was found in the control sample, whereas all sponge cakes with CAPCG had significantly higher acceptance of odour and taste in comparison to the control cake. From the nutritional point of view, sponge cakes substituted with CAPCG showed higher total dietary fibre content than the control wheat sponge cake.

Brewer's spent grain (BSG) is a by-product generated during the brewing process. It is a rich source of dietary fibre and proteins, with great potential to increase nutritional value of food products. In this research different quantities of fresh (non-dried and non-milled) brewer's spent grain (15, 25 and 50%) were added to wheat flour on a replacement basis in order to evaluate its effect on fibre and protein content, instrumental parameters of colour, microbial stability and sensory characteristics of cookies. Protein and fibre content of cookies increased following the addition of BSG from 7.55% to 9.69% and 6.8 to 15.55%, respectively. Considering the colour characteristics, addition of BSG decreased L*and b* values, while a*values increased. Enterobacteriaceae, Escherichia coli, Clostridium spp., yeasts and moulds were not detected in cookie samples, while the Enterobacteriaceae were detected (40 cfu/g) in fresh BSG. The addition of 25% of BSG resulted in best sensory characteristics of cookies in terms of surface appearance, hardness, grittiness and flavour. The results have shown that fresh BSG has a potential to increase nutritional value of the cookies without negative influence on cookie sensory characteristics and microbiological stability.

The aim of this study was to determine the effect of the main milling variables, i.e., agitator shaft speed (50, 75 and 100%, which is 25, 37.5 and 50 rpm) and milling time (30, 45 and 60 min) on physical and sensory properties of fat filling, as well as on energy consumption during the production in a laboratory ball mill. Within the response surface method, the face centered central composite design is used. A response surface regression analysis for responses was performed and a full quadratic model was fitted to the experimental data. It is shown that agitator shaft speed had the most significant influence on physical properties (particle size distribution, rheological and textural propertes) and sensory characteristics of fat filling, while the milling energy consumption is highly influenced by milling time with contribution 55.4%, followed by agitator shaft speed (40.04%). The model obtained by regression analyses was used to perform the optimization of processing parameters in order to provide the combination of agitator shaft speed and milling time that cost less energy while at the same time do not compromise the quality of the fat filling. Optimization of production of fat filling in a laboratory ball mill would imply the maximum agitator shaft speed and 30-min milling time.

One of the potential raw materials which could be used for production of food with added nutritional value is tomato pomace, a by-product from tomato processing. On the other hand, requirements of consumers for diverse food with potential for health benefits impose the need for creation of products made from different cereals. In this respect, the aim of this study was to evaluate the influence of addition of dried tomato pomace on the physical and sensory properties of whole grain rye flour cookies. The whole grain rye flour was substituted with tomato pomace powder in two levels (15% and 25%) in the standard formulation of short-dough cookie. The quality of final products was evaluated by instrumental and sensory methods. The results clearly demonstrated that redness (+a*) and yellowness (+b*) were highly influenced by level of tomato pomace in the cookie formulations due to its content of carotenoid pigments. The spread factor of the cookies made with addition of tomato pomace powder was higher than the control sample. Hardness of the cookie samples decreased for approximately 50% for the cookie sample with 25% tomato pomace level substitution when compared with control sample. According to the results of sensory analysis, substitution level of 15% caused decrease of surface roughness, fracturability, and granularity, as well as increase of caramel flavour intensity. Substitution level of 25% caused higher degree of cookie softening and more pronounced tomato flavour.

Chocolate is a two-phase rheological system. The solid phase, consisting of non-fat cocoa particles, sugar and soy milk is wrapped in a fat phase - cocoa butter. Physical, thermal, textural and organoleptic properties of chocolate depend on the composition of the ingredients, manufacturing process and a properly conducted pre-crystallization phase. For this study, two chocolate masses were produced in a ball mill: one with 15% of soy milk powder (R1) and the other with 20% of soy milk powder (R2). The chocolate mass was produced at different milling times (30, 60 and 90 min), and pre-crystallization temperature (26, 28 and 30oC). The aim of the study was to evaluate the changes caused by different amounts of soy milk powder on the quality of the chocolate. The quality of chocolate was evaluated by comparing the nutritional composition, hardness, thermorheological and thermal properties of the chocolate mass. The results show that chocolate mass R2, due to the presence of higher amounts of soy milk proteins, should be milled longer, and also needs lower temperatures for pre-crystallization. [Projekat Ministarstva nauke Republike Srbije, br. TR 31014]

Oilseed crops are widely cultivated and are related to nutrition and human health as valuable nutraceutical sources with valuable biological properties. The growing demand for oil plants used in human and animal nutrition or for the processing industry has contributed to the diversification and development of a new variety of oil crops. Increased oil crop diversity, besides ensuring reduced sensitivity to pests and climate conditions, has also led to improved nutritional values. In order to enable oil crop cultivation to become commercially sustainable, a comprehensive characterization of newly created varieties of oilseeds, including their nutritional and chemical composition, is required. In this study, two varieties of safflower and white and black mustard were investigated as alternative oil species for nutritional parameters, mainly protein, fat, carbohydrate, moisture, ash, polyphenols, flavonoids, chlorophylls contents, acids and mineral composition, and compared with those of two different genotypes of rapeseeds as a traditional oil crop plant. The proximate analysis found that the highest oil content was found in the oil rape NS Svetlana genotype (33.23%), while the lowest was in black mustard (25.37%). The protein content varies from around 26% in safflower samples to 34.63%, determined in white mustard. High content of unsaturated fatty acids and low content of saturated fatty acid was observed in the analyzed samples. In mineral analysis, the dominant elements were phosphorus, potassium, calcium and magnesium, in descending order. The observed oil crops are also good sources of microelements, including iron, copper, manganese and zinc, accompanied by high antioxidant activity due to the presence of significant amounts of polyphenolic and flavonoid compounds. [ABSTRACT FROM AUTHOR]

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]

The rheological and physical properties of the chocolate mass depend on the ingredient composition as well as the manufacturing process. For the purpose of this work, a milk chocolate mass of identical composition and raw materials was manufactured by using the two different manufacturing processes: a standard manufacturing process (SM) in five-roller mills including conching, and an unconventional manufacturing process in a ball mill (R1). The quality of both milk chocolate masses was examined by the comparison of thermal (differential scanning calorimetry analysis), textural properties (texture analysis), and the content of hard triglycerides (nuclear magnetic resonance spectroscopy). The main goal of this work was to determine whether chocolate can be produced in a ball mill, using the manufacturing process which results in significant savings, without causing drastic changes to the chocolate physical properties. The new manufacturing process rationalises the standard method by combining two phases, namely conching, and refining into a single one. This results in reduced initial and maintenance costs, as well as costs of workforce and fuel, etc. The results have shown that the new chocolate manufacturing process has a positive impact on texture and thermal properties, while the content of hard triglycerides remains the same.

The double Water-in-Oil-in-Water emulsions containing a mixture of pumpkin seed and sunflower oil were prepared with polyglycerol polyricinoleate (PGPR) as a hydrophobic emulsifier and different hydrophilic emulsifiers, whereby Tween 20 showed the best stabilization effects. Two different stabilization methodologies of the Water-in-Oil emulsions, (1) stabilization against molecular diffusion degradation (Oswald ripening) by electrolyte (NaCl) addition and (2) gelling of internal water droplets using alginate to form gel phase were employed. Emulsion with co-stabilizer was more stable during storage and heating/freezing treatment than Gel-in-Oil emulsions. Glucose was introduced as a thickening agent in the external water phase. The regulation of the osmotic pressures between the water compartments by glucose addition to the external water phase can be employed to modulate the release behavior of encapsulated material and improve the droplet stability. Also, simple correlation was proposed to predict the release fraction of the salt toward the external water phase. Practical Applications Due to their low stability the double emulsions are rarely able to overcome the research phase and to this day have not been converted into commercial products. However, as carriers for the preservation of sensitive components from the environmental exposure destruction, emulsions can provide long term retention of encapsulated material and allow the production of low calorie food products. The incorporation of pumpkin seed oil in the double emulsions due to a multitude of valuable components in its composition contributes to nutritional value of products, making in this way designed emulsions a good base for the preparation of the functional food. Second, encapsulation of salt in double emulsions, except the practical application for the preparation of salted creams, enhances the stability of the emulsions and gives the possibility of tracking the release of hydrophilic material from internal water phase. [ABSTRACT FROM AUTHOR]

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