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A new type of functional food products-bread supplemented with yeast extract-was developed and optimized. In the next product development phase, samples of bread with yeast extract were tasted and evaluated by 536 randomly selected consumers, and their acceptability was analyzed.. The survey results showed that consumers in all groups had a high level of awareness about the importance of product labeling and the impact of food on health, while low requirements for special diets. Bread sensory characteristics were highly acceptable, while the final price of bread with yeast extract was 20% higher than regular bread. Correspondence analysis showed differentiation among categories of consumers and their responses. Despite the high importance of product price and lack of proper marketing, there was a high level of consumers' willingness to change their current bread, and buy this new type.

Considerable interest in the consumption of bread from ancient spelt wheat with superior nutritional properties, easy digestibility and pleasant taste and aroma, has arisen recently. Yeast extract (YE) is nowadays frequently used as a natural flavor enhancer for improving organoleptic properties such as meaty, cheesy and savory attributes of different food products. YE is a natural product from the baker’s yeast industry with high nutritional richness containing amino acids, peptides, nucleotides, vitamins and minerals. In this work, the effect of YE, table salt and white sugar content on fermentative activity of yeast and technological properties of spelt bread was investigated by response surface methodology (RSM) aiming to define the optimal conditions for obtaining a new functional product. The addition of YE, salt and white sugar slightly decreased yeast fermentative activity, while CO2 retention in dough was found to depend more on its chemical composition. YE addition (up to 5%) was found to increase volume and decrease firmness of bread prepared from dough with sugar content up to 5%, while the opposite effect was established in bread with higher sugar content. Maximal bread elasticity was obtained for YE content of 1.57%, table salt content of 2.01% and sugar content of 7.15%.

The aim of this research was to evaluate the impact of the most commonly used agents for tartaric stabilization of wine, such as metatartaric acid, carboxymethyl cellulose (CMC), mannoproteins and gum arabic, on the filterability of white, rosé and red wines previously pre-filtered and prepared for the final filtration and bottling. Wine filterability after sweetening with rectified concentrated must was also assessed. The experiments were carried out using the Quality Filterability Test and the obtained results were expressed through the filterability index (FI), and maximum filterable volume (Vmax). The results confirmed that the used enological agents for the inhibition of tartaric instabilities generally did not worsen the filterability of white and rosé wines (FI500). The correlation between white and rosé wine turbidity and filterability was recorded in the trials but the same trend was not registered for the red wine. The results of this study are important since membrane (final) filtration of improperly prepared wine characterized by low filterability can both increase the costs and lead to holdup on the bottling line.

The paper aims to determine the economic viability of the production of spelt and its products. The paper deals with the economic and health aspects of the production and processing of spelt in AP Vojvodina. We used the differential calculation method and, based on the data collected on one farm in AP Vojvodina, tried to evaluate the cost-effectiveness. Despite the lower yield of spelt when compared to wheat, the economic viability of spelt production is higher, due to lower production costs and far higher selling prices. A major constraint on production is product placement, i.e. the market. Three types of bread were analyzed: made from spelt with yeast extract, from spelt without yeast extract and white bread made from wheat only. The cost of producing spelt bread with yeast extract (which is the healthiest one) is higher by RSD 10.44 than the integral bread from spelt without yeast extract, or by RSD 55.69 from wheat bread. The selling price of spelt bread with the addition of yeast extract is 4 times higher than the price of white wheat bread, and 20% higher than the price of spelt bread. The profit from selling bread made from pellets with yeast extract is 23% higher than from selling bread made from integral bread pellets, or 4.3 times (430%) higher than bread from wheat flour type 500.

The purpose of this paper is to examine the effect of certain technological parameters of alcoholic fermentation on the quality of plum wines produced. As part of this research, the application of various commercial pectolytic enzymes to the treatment of plum pomace was examined, as well as the frequency of pomace stirring and the influence of different quantities of plum pit additions to the pomace. The domestic plum cultivar 'Čačanska lepotica' was used as a raw material. The present study gave an insight into the efficiency and justification of the pectolytic enzyme application examined. The once-per-day method of pomace stirring proved to be optimal, whereas the presence of pits during fermentation led to a significant increase in the hydrocyanic acid and benzaldehyde contents of the plum wines analysed. However, the hydrocyanic acid and benzaldehyde contents obtained did not exceed the maximum content allowed.

New 48 wheat varieties, harvested in 2016 are classified in four wheat quality groups (improvers, bread varieties, basic varieties, poor quality varieties), based on minimum level of crude protein content, sedimentation value, flour extraction, yield of bread volume and bread crumb quality.22.9 % of analyzed varieties met all the prescribed parameter values for grading into defined quality groups. The objective of the presented study was to evaluate the quality of the different wheat varieties by integrating physicochemical, rheological and bread characteristics of wheat. Following 13 parameters: test weight, 1000 kernel weight, vitreousness, flour extraction, crude protein content, sedimentation value, wet gluten content, falling number, absorption, farinograph number of quality, extensograph area, yield of bread volume and bread crumb quality were subjected to score analysis. Outcomes may help in better differentiation the quality of wheat varieties. Score analysis has been estimated as a helpful mathematical tool for wheat grading.

Ethanol produced by alcoholic fermentation from renewable sources, referred to as bioethanol, is widely used as an environmentally friendly and renewable energy source, as well as a chemical in various industries such as the medical, food and feed, pharmaceutical and chemical industries. This paper investigates the bioethanol production from sugar beet thick juice by immobilized Saccharomyces cerevisiae cells in calcium alginate beads and in a new matrix in the form of combined alginate-maize stem ground tissue beads. Higher values of fermentation parameters were obtained by yeast immobilized in new calcium alginatemaize stem ground tissue beads in comparison to calcium-alginate beads. A maximum ethanol concentration of 97.2 g/l, an ethanol yield per utilized sugar of 0.494 g/g, a percentage of the theoretical ethanol yield of 96.6 %, and a volumetric ethanol productivity of 2.03 g/lh were obtained at the end of batch alcoholic fermentation of the medium based on sugar beet thick juice with an initial sugar concentration of 200 g/l.

This study determined the influence of the addition of commercial bakery improver (0.1-0.9 %), table salt (1-7 %), and white sugar (1-9 %) into dough on fermentative activity (FA) of yeast, and consequently CO2 production, to improve dough handling and quality of wheat bread by using an optimized additive combination. The FA of yeast cells was evaluated using fermentograph SJA device. The addition of white sugar in the amount of 1-4 % and complex additive in the amount 0.1-0.5 % enhances FA of yeast. Further increase of the amount of these two compounds decreases the FA. The addition of table salt in the amount of 1-7 % negatively affected the FA. The optimal amounts of complex additive, table salt and white sugar, obtained by response surface methodology (RSM) using Design Expert software, which provided maximum FA of 1171.31 ml CO2/gdm/2h were the following: 0.41, 1.0 and 3.91 % based on flour weight, respectively.

A simple, low cost, and effective method for the removal of acridine orange (AO), a mutagenic cationic dye, from aqueous model solutions by adsorption onto dried sugar beet pulp (SBP) was evaluated in the present study. The AO removal was enhanced along with the increase of the initial solution pH and dye concentration. It was found that the adsorption process closely follows a pseudo-second-order chemisorption kinetics. The obtained equilibrium data obey both the Freundlich and Langmuir isotherm models. The SBP was proved to be very promising adsorbent for AO removal. Maximum adsorption capacity of the Langmuir monolayer of SBP for AO was found to be 5.37, 34.6, 89.62, 144.53 and 324.58 mg/g, at 25°C for the solution pH of 2, 4, 5, 6, and 8, respectively. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR-31002]

Continuous adsorption of methylene blue from aqueous solutions onto maize stem ground tissue in column mode was investigated. The study encompassed the effects of important parameters such as flow rate, initial concentration of methylene blue, and bed depth on methylene blue removal from model solutions. The maximum adsorption capacity of the maize stem was 45.9 mg/g at the initial methylene blue concentration of 20 mg/L, bed height of 6.5 cm and flow rate of 8 mL/min. It was found that the breakthrough time for reaching saturation increased with a decrease in the flow rate, and also occurred earlier for a higher influent concentration. The breakthrough times increased with the bed depth, thus allowing a larger volume to be treated. The Adams-Bohart, Yoon-Nelson, Clark and artificial neural network models were used to predict the breakthrough curves. These models gave excellent approximations of the experimental behavior.[Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 172025]

The purpose of this study is to examine the effect of bakery yeast extract (YE) addition, in the form of a paste (up to 10 % to the wheat flour mass) on the fermentative activity (FA) of bakery yeast during dough preparation. The addition of YE in an amount of 1-5 % had no statistically significant influence on the fermentative performance of Saccharomyces cerevisiae in dough. A further increase in the amount of YE added, namely from 5 % to 10 %, decreased the FA from 884.61 to 777.26 ml CO2/g dm 2h, which corresponds to 12.1 %. The decrease in FA with the addition of YE in an amount over 5 % was much more pronounced in the second hour of the fermentation. Furthermore, YE was found to be an excellent source of protein (70.42 g/100 g of dry mass) and different minerals, especially Mg (513.91 mg/kg on a dry mass basis) and Ca (36.27 mg/kg), enabling the production of protein- and mineral-enriched bread.

This study investigated the effect of certain apricot varieties cultured in Serbia on the quality of produced brandies, primarily in terms of the content and relationships of aromatic substances. In this study, fruits of three apricot varieties (NS 6, NS rodna and Ambrozija) were used for production of brandies. Primary fruit processing and distillation were carried out in a distillery of industrial capacity. High differences in the quantity of 14 identified aromatic components of the distillates produced from three apricot varieties were recorded. Ethyl decanoate was present in all three distillates in significantly larger amounts compared to other esters. Ethyl isobutyrate was found in a small amount (0.32 mg/L) in the distillate produced from Ambrozija variety, while in the distillates from other varieties this compound was not detected. The distillates produced from varieties NS6 and NS rodna contained significantly higher amounts of ethyl lactate (12.50 to 13.46 mg/L) compared to the distillate from Ambrozija variety (8.87 mg/L). The content of linalool determined in NS6 distillate was three times higher (22.12 mg/L) in comparison to the distillate from Ambrozija (7.31 mg/L).

In this paper yields of bioethanol from seven samples of bread were compared. Samples of bread were produced and prepared in a laboratory by mixing wheat and buckwheat flour in amounts of 0, 20, 40, 50, 60, 80 and 100%. At first, the analysis of all seven samples of bread was done (dry matter, starch content and pH value of bread sample suspensions). Then the waste bread suspensions were hydrolyzed by applying commercial hydrolytic enzymes, Termamyl® SC and SAN Extra® L. The fermentation process was carried out with dry instant yeast, Saccharomyces cerevisiae, after which distillation of all fermented suspensions was performed. The ethanol contents in the distillates of all seven samples were determined. The highest yield of bioethanol was detected in the bread sample made of pure wheat flour. The ethanol yield gradually decreased with increasing content of buckwheat flour in bread. These results could be useful when considering the possibility of utilization of waste bread from different sources as a feedstock for bioe­thanol production.

Jerusalem artichoke (JA) is a low-requirement crop, which does not interfere with food chain, and is a promising carbon source for industrial fermentation. Microbial conversion of such a renewable raw material to useful products, such as ethanol, is an important objective in industrial biotechnology. In this study, ethanol was efficiently produced from the hydrolyzates of JA obtained at different pH values (pH 2.5, pH 3.0 and pH 3.5), temperature (120, 130, 132 and 134°C) and hold time (30 and 60 min) by Saccharomyces cerevisiae. The efficient degradation of JA by HCl under certain experimental conditions was confirmed by thin-layer chromatography. Ethanol concentration of 7.52% (w/w), which corresponds to 93.89 % of the theoretical yield is achieved by ethanol fermentation of JA hydrolyzate obtained at pH 2.5. [Projekat Ministarstva nauke Republike Srbije, br. TR-31002]

The immobilization of Saccharomyces cerevisiae onto sugar beet pulp (SBP) by natural adhesion is an efficient and low-cost method for retaining high biocatalyst density in the ethanol fermentation system. In the present study, cells of S. cerevisiae 163, were immobilized by natural adhesion onto SBP. The retention of immobilized cells attained the level of about 1.7×1011 cells/gram of dry SBP. Continuous ethanol production from sugar beet thick juice (TJ) was performed in a cylinder glass bioreactor at a temperature of 30ºC and pH 5 during a 27-day period. The stability of the fermentation process at dilution rate (D) of 0.025 h-1 and 0.05 h-1 was evaluated. The yeast-SBP system was shown to be stable for over a 15-day period at the dilution rate of 0.025 h-1, while the dilution rate of 0.05 h-1 was found to be unsuitable due to the intensive yeast leaching from the support. At D of 0.025 h-1 the maximum sugar utilization (Su), ethanol concentration (P), volumetric ethanol productivity (Qp), ethanol yield (Yp/s) and fermentation efficiency were 97.1%, 54.7 g/l, 2.3 g/lh, 0.498 g/g and 97.6%, respectively. [Projekat Ministarstva nauke Republike Srbije, br. TR-31002]

Considering the common use of sheet filtration for clarification of fruit brandies, the aim of this study was to evaluate the influence of its application on the stability and composition of volatile compounds of apricot brandy after cold stabilisation. Cold stabilisation treatment involved holding of the brandy at -1°C during 24 hours. Five depth filter sheets with the nominal retention rate of 0.3 μm, 0.5-0.7 μm, 0.7-1.0 μm, 1.0-2.0 μm and 2.5-4.0 μm, were tested in the study. It was shown that all assessed filter sheets were efficient in removing chill haze by significantly reducing the content of fatty acid esters (primarily ethyl palmitate and ethyl laurate). Other volatile and aromatic compounds were not significantly influenced by the applied treatments. However, the filter sheets with higher nominal retention rate (> 0.7 μm), had a smaller impact on the sensory characteristics of the apricot brandy. The re-exposure to lower temperatures did not lead to chill haze formation in any sample obtained after sheet filtration. [Projekat Ministarstva nauke Republike Srbije, br. TR-31002]

Natural adhesion of Saccharomyces cerevisiae onto sugar beet pulp (SBP) is a very simple and cheap immobilization method for retaining high cells density in the ethanol fermentation system. In the present study, yeast cells were immobilized by adhesion onto SBP suspended in the synthetic culture media under different conditions such as: glucose concentration (100, 120 and 150 g/l), inoculum concentration (5, 10 and 15 g/l dry mass) and temperature (25, 30, 35 and 40°C). In order to estimate the optimal immobilization conditions the yeast cells retention (R), after each immobilization experiment was analyzed. The highest R value of 0.486 g dry mass yeast /g dry mass SBP was obtained at 30°C, glucose concentration of 150 g/l, and inoculum concentration of 15 g/l. The yeast immobilized under these conditions was used for ethanol fermentation of sugar beet molasses containing 150.2 g/l of reducing sugar. Efficient ethanol fermentation (ethanol concentration of 70.57 g/l, fermentation efficiency 93.98%) of sugar beet molasses was achieved using S. cerevisiae immobilized by natural adhesion on SBP. [Projekat Ministarstva nauke Republike Srbije, br. TR-31002]

Cell immobilisation in alcoholic fermentation has been extensively studied during the past few decades because of its technical and economical advantages over those of free cell systems. A biocatalyst was prepared by immobilising a commercial Saccharomyces cerevisiae strain (baker yeast) on corn stem ground tissue for use in alcoholic fermentation. For this purpose, the yeast cells were submitted to the batch tests 'in situ' adsorption onto pieces of the corn stem ground tissue. Cells immobilisation was analysed by optical microscopy. It was determined that the addition of the corn stem ground tissue led to an increase of the pH value, total dissolved salts content, and sugar content in fermentation medium. The addition of 5 and 10g of the corn stem ground tissue per liter of medium, increased ethanol yield, decreased amount of residual sugar and the cells immobilisation was effective. Corn stem is one of the abundant, available, inexpensive, stable, reusable, nontoxic celulosic biomaterial with high porosity, which facilitates the transmission of substrates and products between carrier and medium. The prepared immobilised biocatalyst showed higher fermentation activity than free cells. The results indicate that corn stem might be an interesting support for yeast cell immobilisation, and also a cheap alternative recourse of mineral components with possibility of application for improving ethanol productivities.

The need to freeze dough is increasing in bakery production. Frozen dough can be stored for a long time without quality change. The capacity of bakery production can be increased in this way, and in the same time, the night shifts can be decreased. Yeast cells can be damaged by freezing process resulting in poor technological quality of dough after defrostation (longer fermentation of dough). The influence of frozen storage time of dough on survival percentage of Saccharomyces cerevisiae was investigated. Dough samples were taken after 1, 7, 14 and 28 days of frozen storage at -20°C. After defrosting, at room temperature, samples were taken from the surface and the middle part of dough (under aseptic conditions), and the percentage of living S. cerevisiae cells was determined. During frozen storage of dough, the number of living S. cerevisiae decreased. After 28 days of frozen storage, the percentage of live cells on the surface and inside the dough was 53,1% and 54,95%, respectively. The addition of k-carragenan to dough increased the percentage of living cells in the middle part of dough up to 64,63%. Pure cultures, isolated from survived S. cerevisia cells in frozen dough by agar plates method (Koch's method), were multiplied in optimal liquid medium for yeasts. The content of cytochromes in S. cerevisiae cells was determined by spectrophotometric method. The obtained results showed that the content of cytochromes in survived S. cerevisiae cells was not affected by dough freezing process. Growth rate and fermentative activity (Einchor's method) were determined in multiplied cells.

Triticale (Triticosecale) is a crop species resulting from a plant breeder's cross between wheat (Triticum sp.) "mother" and rye (Secale sp.) "father". Today, it has been cultivated in more than 50 countries worldwide. During the researches conducted over period 2005-2006, the quality of three varieties of triticale was examined. Chemical quality parameters were the scope of the paper. The analyzed varieties of triticale showed high a-amylase activity, that was measured by falling number and amylolitic activity. While investigating thermal preparation of the samples at three different temperatures 60, 70 and 90°C, the optimum temperature was determined. Three different modes of thermal preparations were applied in the experiment: 1) without the addition of technical enzymes (a-amylase and glucoamylase), 2) with the addition of glucoamylase, and 3) with the addition of glucoamylase and a-amylase. The enzymes were dosed according to the recommendations of the manufacturer. The thermal preparation of samples conducted at 90°C, produced the lowest content of fermentable starch. This is due to inactivation of amylolytic enzymes in triticale at 90°C. During 2006, the survey on bioethanol production from triticale was directed towards lowering the temperature regimes of the preparation step up to 60°C. During the first preparation mode (without the additional enzymes), the obtained results for the content of fermentable starch and the ethanol yield, showed that native amylolytic enzymes of triticale can degrade 80-90% of the available starch. The addition of glucoamylase, during the second preparation mode, increased the content of fermentable starch and ethanol yield. The best results were achieved applying the third mode of preparation. Comparing the preparation modes, it could be concluded that the application of both a-amylase and glucoamylase in the preparation step increased the content of fermentable starch and ethanol yield by 7-13%. Further research should optimize the addition of a-amylase and glucoamylase. According to the results, the thermal preparation modes at 60°C are considered more suitable because of the energy savings.

Processing parameters of Kantata wheat variety indicate that it is not suitable for bread making. Therefore, an investigation was carried out to evaluate the suitability of the variety for ethanol production. Wheat was cultivated at the following sites: Kovin, Zrenjanin, Pančevo and Vrbas. Ethanol yields depend on the location on which the samples were grown and on the temperature during thermal and enzymatic preparation of flour samples. Wheat sample cultivated on the Vrbas site gave the highest ethanol yield.

The aim of this study was the investigation and comparison of the potential of sugar beet molasses and thick juice as raw materials for bioethanol production, as renewable and sustainable energy sources. Ethanol fermentation of a wide range of initial sugar concentrations (100–300 g/L) was performed using either free or immobilised Saccharomyces cerevisiae in calcium alginate beads in the absence of any added nutrients. In general, immobilised cells showed better fermentative performance, enhanced ethanol productivity, stability and cell viability compared with free cells, under the same fermentation conditions. The high concentration of non‐sugar components contained in molasses affected yeast fermentation performance and viability. Maximum ethanol concentration in fermented media of 84.6 and 109.5 g/L were obtained by immobilised cells for initial sugar concentrations of 200 and 250 g/L for molasses and thick juice, respectively. However, the highest ethanol yields of 31.7 L per 100 kg of molasses and 37.6 L per 100 kg of thick juice were obtained by immobilised cells at an initial sugar concentration of 175 g/L. In the high gravity fermentation process, thick juice resulted in a higher ethanol yield per mass of raw material compared with molasses. This study shows the advantage of immobilised yeast for the efficient production of high gravity bioethanol from thick juice, which was a more favourable raw material than molasses. © 2018 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

The effects of yeast extract addition, with varied quantities of salt and sugar, on the chemical and mineral composition, colour and sensory properties of spelt bread, in order to obtain new products were investigated. The addition of 5 % yeast extract positively influenced the mineral characteristics and increased protein content by 30.77 %. As a salt substitution, addition of yeast extract improved appearance without deteriorating texture descriptors and breadcrumb quality, while the taste became more complex, but without increasing salty taste. Addition of sugar in samples with yeast extract, improved most sensory characteristics. The developed mathematical models of bread with yeast extract quality parameters were statistically significant, indicating the satisfactory approximation of the bread quality parameters within the varied formula. Bread samples with addition of 5 % yeast extract, 1.5 % of salt and 0 % sugar were determined as the best from the aspect of overall quality. A new product was obtained with good total quality, higher level of nutritional value and reduced salt content.

Kitchen waste is highly biodegradable component of municipal solid waste, which mainly includes leftover food generated from the kitchen at various places of food preparation such as restaurants, hotels, canteens etc. This waste is a promising source for ethanol production due to its abundant availability, low cost and high carbohydrates content that can be converted to fermentable sugars. The aim of this study was to investigate and optimise the thermo-chemical pre-treatment of representative mixed sample of kitchen waste and to evaluate ethanol production from obtained fermentable sugars. Box-Behnken experimental design was employed to optimise the parameters of hydrolysis: pH, temperature and hydrolysis time. Second order polynomial models were developed to quantify the relationships between variables. Maximum yield of fermentable sugars of 130g and maximum ethanol concentration of 65 g per kilogram of kitchen waste containing 190 g of total sugar were obtained with the following optimum pre-treatment conditions: pH 1.0, temperature 120°C and hydrolysis time 60 min. [ABSTRACT FROM AUTHOR]