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Low-Energy Strawberry Fruits of Joly Cultivar, the First Step Towards a Novel, Food-Based Solution for the Obese Population
No full textThis study aimed to produce low-energy strawberries of the Joly cultivar by breeding them under different growing conditions. The efficacy of such a process was screened by the means of common physico-chemical parameters underpinned with the findings of elementary chemical analysis. The preferred strawberry breed line (treated with microbiological fertiliser of choice) showed both a decreased energy value (130 +/- 6 kJ/100 g or 31.07 kcal) and an increased water content (91.0 +/- 7.3 g/100 g). Due to a rich content of phenolic compounds (Total Phenolic Content/TPC/4184 +/- 39 mg GAE/kg; Total Anthocyanin Content/TAC/394 +/- 4 mg C3GE/kg), it also exhibited potent antioxidant activity (0.110 +/- 0.008 %/mu L, HPMC /Hydroxo-Perhydroxyl Mercury(II) Complex/) assay; EC50 = 2.01 +/- 0.10 mu g and ARP = 0.50 +/- 0.05 mu g(-1), DPPH assay). Finally, the polyphenolic extract of the same breed line showed high anti-alpha, glucosidase activity (IC50 = 19 +/- 1 mu g/mL), being more than four-fold active compared to acarbose (IC50 = 78 +/- 4 mu g/mL), the anti-diabetic drug used as a positive control. Taken all together, the utilisation of microbiological fertiliser (Bacillus sp.) in tunnels might be recommended for the breeding of low-energy strawberries of the Joly cultivar (the starting point for developing of novel functional foods targeting the obese population) in the same or similar agricultural conditions, if further studies confirm its likely potential and credibility
Anti-biofilm activities of essential oils rich in carvacrol and thymol against Salmonella Enteritidis
No full textThe aim of the present study was to determine the bioactive compounds in four essential oils (EO's) from Origanum heracleoticum, Origanum vulgare, Thymus vulgaris and Thymus serpyllum and to assess their antimicrobial and anti-biofilm activity against Salmonella Enteritidis. Strains were previously characterized depending on the expression of the extracellular matrix components cellulose and curli fimbriae as rdar (red, dry and rough) and bdar morphotype (brown, dry and rough). This study revealed that the EO's and EOC's (carvacrol and thymol) investigated showed inhibition of biofilm formation at sub-minimum inhibitory concentration. Comparing the efficacy of EO's and EOC's in the inhibition of biofilm formation between the strains with different morphotype (rdar and bdar) did not show a statistically significant difference. Results related to the effectiveness of EO's and EOC's (the essential oil components, carvacrol and thymol) on eradication of preformed 48 h old biofilms indicated that biofilm reduction occurred in a dose-dependent manner over time
Characterization analysis of Poplar fluff pyrolysis products. Multi-component kinetic study
No full textThis paper describes the pyrolysis of Poplar fluff (from Populus alba) using on-line apparatus, and carbonization process at 850 degrees C using the fixed bed reactor. Characteristics of pyrolysis products were examined. Elemental and chemical analyses were shown that Poplar fluff has higher energy content characterized by increased content of fibrous structure (particularly cellulose). Independent parallel reactions model very well describes devolatilization process. It was found that increased amount of extractives can significantly affect on increased release of light gaseous products, but declining hydrocarbons, mostly the alkanes. Liquid product is mainly composed of phenolics, aldehydes, acids, esters and ketones. The carbonization process produces the great abundance of polycyclic aromatic hydrocarbons (PAH's), where naphthalene is the most abundant. Mechanism for PAH's formation was suggested. This study represents the first step in a much wider and more comprehensive way in thermal conversion processes of this type of fuel
Optimization of fish osmotic treatment applying fuzzy synthetic evaluation method
No full textOsmotic treatment is used alone or in combination with other drying methods to reduce water content in food and increase its sustainability. Due to the many advantages over traditional drying processes, the osmotic treatment is increasingly being used in the food industry as a preservative method. The complexity of the process causes nonlinear optimization problems and sometimes it is difficult to determine the inter-dependencies between dependent and independent variables. However, by using improved mathematical models and optimization algorithms, it is possible to technologically improve and plan the production process. For this experiment three different osmotic solutions (sugar beet molasses (OS1), aqueous solution of sodium chloride (OS2) and sucrose and the blend of OS1 and OS2 in a 1: 1 ratio (OS3) were used for osmotic drying treatment of fish meat (Carassius gibelio). The treatment was performed for 5 hours, under atmospheric pressure, at four different temperatures. This work is concerned with determination of the optimum drying conditions by using Fuzzy synthetic evaluation-FSE. The optimization of eight response variables (water loss-WL, solid gain-SG, aw, dry matter content-DM and mineral content (K, Na, Ca, Mg) was based on models already developed by second order polynomial-SOP and artificial neural network-ANN. The function maximum F represents the optimal values of the dependent variables and for OS1 was 0.34, 0.36, 0.36, 0.35, for OS2: 0.52, 0.57, 0.60, 0.62 and for OS3: 0.69, 0.74, 0.80 and 0.88. Value of this function that is closer to 1 shows that process parameters are optimal. It can be concluded that by using the FSE method the optimum values of the process parameters for the OS1 were at lower temperatures and at lower concentrations, while for the OS2 and OS3 the optimal values were reached at the maximum observed temperature range and concentrations.Osmotic treatment is used alone or in combination with other drying methods to reduce water content in food and increase its sustainability. Due to the many advantages over traditional drying processes, the osmotic treatment is increasingly being used in the food industry as a preservative method. The complexity of the process causes nonlinear optimization problems and sometimes it is difficult to determine the inter-dependencies between dependent and independent variables. However, by using improved mathematical models and optimization algorithms, it is possible to technologically improve and plan the production process. For this experiment three different osmotic solutions (sugar beet molasses (OS1), aqueous solution of sodium chloride (OS2) and sucrose and the blend of OS1 and OS2 in a 1: 1 ratio (OS3) were used for osmotic drying treatment of fish meat (Carassius gibelio). The treatment was performed for 5 hours, under atmospheric pressure, at four different temperatures. This work is concerned with determination of the optimum drying conditions by using Fuzzy synthetic evaluation-FSE. The optimization of eight response variables (water loss-WL, solid gain-SG, aw, dry matter content-DM and mineral content (K, Na, Ca, Mg) was based on models already developed by second order polynomial-SOP and artificial neural network-ANN. The function maximum F represents the optimal values of the dependent variables and for OS1 was 0.34, 0.36, 0.36, 0.35, for OS2: 0.52, 0.57, 0.60, 0.62 and for OS3: 0.69, 0.74, 0.80 and 0.88. Value of this function that is closer to 1 shows that process parameters are optimal. It can be concluded that by using the FSE method the optimum values of the process parameters for the OS1 were at lower temperatures and at lower concentrations, while for the OS2 and OS3 the optimal values were reached at the maximum observed temperature range and concentrations
Contemporary methods of stinging nettle (Urticadioica L.) extractions, composition and application of extracts
No full textGlavni cilj istraživanja ove doktorske disertacije je bio ispitivanje hemijskog sastava lista koprive (Urtica dioica L.), primena različitih ekstrakcionih tehnika radi izolovanja aktivnih jedinjenja iz lista, ispitivanje njihovog hemijskog sastava, kao i formulacija prehrambenog proizvoda dodavanjem ekstrakta lista. U cilju ispitivanja sastava lista primenjene su različite analitičke tehnike kao što su GC/MS, GC/FID, UHPLC-DAD/MS/MS, ICP-OES, živin analizator, AAS i spektrofotometrija. Pri tome je dokazano prisustvo različitih klasa hemijskih jedinjenja među kojima su pigmenti (hlorofil i karotenoidi), terpenoidi, fenolni i polifenolna jedinjenja, vitamini (vitamin C i vitamini B grupe) i masne kiseline. Za izdvajanje biološki aktivnih jedinjenja primenjene su različite tehnike ekstrakcije, kao što su: maceracija, Soxhlet ekstrakcija, ultrazvučna (UAE), mikrotalasna (MAE) i superkritična ekstrakcija (SFE). Preliminarne UAE ekstrakcije su pokazale da je voda bila najpogodnija kao rastvarač, odnosno da su vodeni ekstrakti pokazali najveću antioksidativnu aktivnost, kao i najveći sadržaj ukupnih fenola (TPC) i flavonoida (TFC). Pripremljeni vodeni ekstrakti su dalje ispitivani u pogledu sastava, antioksidativne, citotoksične i antimikrobne aktivnosti, gde su rezultati međusobno poređeni kako bi se odabrala najpogodnija ekstrakciona tehnika. Kod SFE je ispitan uticaj uslova ekstrakcije, odnosno pritiska i temperature na sastav dobijenih ekstrakata i njihovu biološku aktivnost (antioksidativna i citotoksična). Iscrpljeni list korpive je nakon SFE bio ekstrahovan primenom UAE i MAE tehnika, gde su dobijenim ekstraktima utvrđeni sastav i biološka aktivnost. Nakon svih ispitivanja, MAE ekstrakt i suvi list koprive su dalje primenjeni u formulaciji prehrambenog proizvoda (hleba), gde je variran njihov sadržaj, dok su analizirani sastav, tehnološki kvalitet hleba, kao i biološka aktivnost (antioksidativna i citotoksična).The main goals of this PhD thesis were investigation of chemical composition of stinging nettle leaves (Urtica dioica L.), application of different extraction techniques for isolation of biologically active compounds from leaves, investigation of their chemical composition and formulation of food product with addition of dried leaves and/or its extract. For those purposes, different analytical techniques were applied, i.e. GC/MS, GC/FID, UHPLCDAD/ MS/MS, ICP-OES, direct mercury analyzer, AAS and spectrophotometry. Different classes of chemical compounds were detected and identified, such as: pigments (chlorophylls and carotenoids), terpenoids, phenolic and polyphenolic compounds, vitamins (vitamin C and B group) and fatty acids. For the purpose of isolation of biologically active compounds, different extraction techniques were applied: maceration, Soxhlet extraction, ultrasound (UAE), microwave (MAE) and supercritical (SFE) extraction. Preliminary conducted extraction, as well as total phenolics (TPC) and flavonoids (TFC) contents, showed that water was the most suitable solvent for further course of investigation. Water extracts were further analyzed regarding their chemical composition, antioxidant, cytotoxic and antimicrobial activities. Obtained result were compared in order to select the most efficient extraction technique. In the case of SFE, influence of pressure and temperature on extraction yield, composition and biological activity of prepared extracts were monitored. Exhausted plant material after SFE was used for further MAE extraction, while obtained extracts were analyzed to investigate chemical composition and biological activity. After conducted experiments and analysis, MAE extract was used for formulation of food product (bread) where it was added in different amounts in combination of without dried leaves. Obtained products were analyzed regarding their chemical composition, technological requirements and biological activity
Natural additives in functional egg production
No full textKonzumna jaja mogu igrati važnu ulogu kao funkcionalna hrana ako se za njihovu proizvodnju koriste posebno dizajnirane smeše obogaćene o-3 masnim kiselinama, prirodnim pigmentima i vitaminima. Dakle, cilj ove studije bio je istražiti efekte uključivanja koekstrudata na bazi lanenog semena u kombinaciji sa prirodnim pigmentima u ishranu kokoši nosilja i ispitivanje njihovog uticaja na fizička svojstva, boju žumanca i sastav masnih kiselina jaja. Sto dvadeset Lohmann Brown kokoši nosilja hranjeno je na bazi kukuruzno-sojinog obroka uz dodatak koekstrudata lana u različitim proporcijama: 0% (kontrolni K1 i K2), 13,50% (E1) i 22,50% (E2). Kontrolni tretman (K1) sadržao je do 3% masti, bez dodatih pigmenata, dok je kontrolni tretman (K2) sadržao do 5% masti i sintetičke pigmente. Eksperimentalni tretmani E1 i E2 (sa 3% i 5% masti) imali su istu količinu prirodnih pigmenata (1% šargarepe i 0,5% paprike). Kod jaja iz eksperimentalnih tretmana E1 i E2 nisu primećene značajne promene (p>0,05) u karakteristikama kvaliteta jaja u poređenju sa kontrolnim jajima. Poželjna boja žumanca od 12,78 po RYCF (Roche Yolk Colour Fan skala) postignuta je u oba eksperimentalna tretmana E1 i E2. Jaja od kokoški hranjenih sa koekstrudatom lana imala su značajno viši nivo (p LT 0,001) a-linolenske (6,46% za E1 i 8,87% za E2), dokozaheksaenske (2,01% za E1 i 2,08% za E2) i eikozapentaenske (0,17% za E1 i 0,21% za E2) kiseline nego jaja iz kontrolnih tretmana. Odnos o-6/o-3 od 1,43 i 1,01 u tretmanima E1 i E2, respektivno, bio je značajno niži (p LT 0,001) od odnosa o-6/o-3 u kontrolnim tretmanima K1 i K2 (9,40 i 8,88, redom). Sadržaj tokoferola u jajima iz eksperimentalnih tretmana E1 i E2 bio je 6 i 8 puta veći nego u jajima iz kontrolnog tretmana K1, kao i 1,8 i 2,3 puta veći nego u jajima iz kontrolnog tretmana K2, respektivno. Dodavanjem koekstrudata lana i prirodnih pigmenata u ishranu kokoši nosilja moguće je proizvesti funkcionalno jaje sa poželjnom bojom žumanca i sastavom masnih kiselina.Table eggs can play an important role as functional food, especially if specially designed mixtures enriched with o-3 fatty acids, natural pigments and vitamins are used for their production. Thus, the aim of this study was to investigate the effects of inclusion of flax-corn meal co-extrudate (FCM) in combination with natural pigments in hens' diet on physical properties, yolk colour and fatty acid composition of eggs. One hundred and twenty Lohmann Brown laying hens were fed corn-soybean meal based diet with the addition of FCM at different levels: 0% (control C1 and C2), 13.50% experimental treatment (E1) and 22.50% experimental treatment (E2). The control treatment (C1) contained up to 3% fat, without added pigments while the control treatment (C2) contained up to 5% fat and synthetic pigments. Experimental treatments E1 and E2 (3% and 5% fat, respectively) had the same amount of natural pigments (1% carrot and 0.5% paprika). When compared with control eggs, no significant changes (p>0.05) in the egg quality characteristics were observed for E1 and E2 eggs. Desirable egg yolk colour of 12.78 RYCF (Roche Yolk Colour Fan scale) was achieved in the treatments E1 and E2. Eggs from hens fed FCM had significantly higher level (p LT 0.001) of a-linolenic (6.46% for E1 and 8.87% for E2), docosahexaenoic (2.01% for E1 and 2.08% for E2) and eicosapentaenoic (0.17% for E1 and 0.21% for E2) acids in comparison to eggs originated from hens fed control diets. The o-6/o-3 ratios of 1.43 and 1.01 in the treatments E1 and E2, respectively, were significantly lower (p LT 0.001) than o-6/o-3 ratios in the control treatments C1 and C2 (9.40 and 8.88, respectively). The content of tocopherol in eggs from the experimental treatments E1 and E2 were 6 and 8 times higher than in eggs from the control treatment C1 as well as 1.8 and 2.3 times higher than in eggs from the control treatment C2, respectively. By the addition of FCM and natural pigments in hens' diet, it is possible to produce functional egg with desirable colour and fatty acid composition
A business model in agricultural production in Serbia, developing towards sustainability
No full textAgricultural production is a Serbian main economic sector, presenting a base for the food industry. By analysing the public available data of the agriculture sector, applying a newly developed business model it is possible to assess the current situation and to realize the relation between variables, which can also be used for prediction of future trends in agricultural production and food industry. Within this paper an attempt was made to develop a novel artificial neural network model for better understanding the relation between the observed parameters and to estimate the efficiency in sustainability achievement and sector potential the well-known Cobb-Douglas production model was compared to the newly developed model. The presented models could be used to achieve the transformation towards a circular bioeconomy, by developing the national strategies for sustainable agricultural production, with the aim of better utilization of resources and reduction of wastes
Experimental Optimization of Nimonic 263 Laser Cutting Using a Particle Swarm Approach
No full textThis paper presents an experimental study carried out on Nimonic 263 alloy sheets to determine the optimal combination of laser cutting control factors (assisted gas pressure, beam focus position, laser power, and cutting speed), with respect to multiple characteristics of the cut area. With the aim of designing laser cutting parameters that satisfy the specifications of multiple responses, an advanced multiresponse optimization methodology was used. After the processing of experimental data to develop the process measure using statistical methods, the functional relationship between cutting parameters and the process measure was determined by artificial neural networks (ANNs). Using the trained ANN model, particle swarm optimization (PSO) was employed to find the optimal values of laser cutting parameters. Since the effectiveness of PSO could be affected by its parameter tuning, the settings of PSO algorithm-specific parameters were analyzed in detail. The optimal laser cutting parameters proposed by PSO were implemented in the validation run, showing the superior cut characteristics produced by the optimized parameters and proving the efficacy of the suggested approach in practice. In particular, it is demonstrated that the quality of the Nimonic 263 cut area and the microstructure were significantly improved, as well as the mechanical characteristics
Prediction of commercial spaghetti quality based on sensory and physicochemical data
No full textIn this paper, a range of nine commercial spaghetti samples was studied to compare and describe relationships between physicochemical and sensory data. Analysis of variance showed that all examined sensory and physicochemical properties were significant (p LT .05) in discriminating the samples, which could support the usefulness of their application in characterizing the spaghetti appearance quality. According to the results of sensory analysis, the samples were differentiated into four significantly different quality groups, regarding the overall appearance of the samples, as well as all individually evaluated attributes. Successful rating of the appearance quality of commercial spaghetti can be conducted on the basis of instrumental determinations, in the first place using color and mechanical characteristics. Principal component analysis was used to discriminate groups of samples according to similarity in physicochemical and sensory parameters, and the first two principal components explained 75.04% of the total variance of samples. This work can be useful for manufacturers and technologists in the pasta production sector, who wish to improve the performance of their productive and quality control process in order to satisfy consumer demands and expectations of spaghetti. The selected physicochemical parameters could be used in future studies to evaluate various production samples of dried spaghetti by establishing models and investigating the predictability of sensory appearance quality. Practical applicatio
Polysaccharides of Pleurotus flabellatus strain Mynuk produced by submerged fermentation as a promising novel tool against adhesion and biofilm formation of foodborne pathogens
No full textFoodborne bacteria biofilms present a major concern for the food industry. Although their numerous biological activities are well established, there is little research to date on the use of polysaccharides of mushroom origin as a possible solution for preventing biofilm formation. Therefore, the aim of this study was to examine the anti adhesion and antibiofilm effects of several types of Pleurotus flabellatus strain Mynuk polysaccharide extracts (PFSMpe), produced by air-lift submerged fermentation, against American Type Culture Collection (ATCC) and clinical strains of foodborne bacteria, as well as the cytotoxicity of these extracts. PFSMpe exhibited antiadhesion activity toward clinical isolates, and the percentage of adhesion inhibition was highest for water (WE) and exopolysaccharide (EXOPE) extracts (> 50%) against Enterococcus faecalis. Selected ATCC strains were more resistant than clinical strains, indicating the antiquorum sensing mechanism of PFSMpe action. Antibiofilm activity was similar to antiadhesion activity and WE showed the strongest effect, again on E. faecalis. Differences in antiadhesion and antibiofilm effects of PFSMpe may be explained by differences in chemical composition, with crude extracts showing greater efficiency due to a synergistic effect. PFSMpe did not exhibit cyctotoxic activity against normal human cell lines. Overall, the findings of this study show that PFSMpe represents a promising novel strategy against bacterial biofilms