Utilization of tomato processing byproduct as raw material for value-added food products

U okviru disertacije su razvijeni postupci za iskorišćenje sporednog produkta prerade paradajza (tropa) kao polazne sirovine za proizvodnju prehrambenih proizvoda sa dodatom vrednošću. Sprovedena istraživanja kretala su se u dva smera: proizvodnja lipofilnih i hidrofilnih ekstrakata od liofilizovanog tropa paradajza, primenom rastvarača koji su dozvoljeni za upotrebu u prehrambenoj industriji (n-heksana i 95% etanola) i njihova karakterizacija u pogledu sadržaja i sastava fitohemikalija i biološke aktivnosti in vitro; razvoj formulacija i tehnoloških postupaka za kreiranje gotovih proizvoda sa povećanim sadržajem prehrambenih vlakana i njihova karakterizacija u smislu nutritivnih, reoloških i senzorskih svojstava. Proizvedena su tri proizvoda sa povećanim sadržajem prehrambenih vlakana: kečap od svežeg tropa paradajza, kečap od liofilizovanog tropa paradajza u prahu i marmelada od liofilizovanog tropa paradajza u prahu. Proizvedeni lipofilni i hidrofilni ekstrakti pokazali su sposobnost redukcije jona gvožđa, kao i antiradikalsku aktivnost na DPPH, azot (II)-oksid i superoksid-anjon radikale. Karotenoidi detektovani u lipofilnim ekstraktima (likopen i β-karoten) povezani su sa višom antiradikalskom aktivnošću na superoksid-anjon radikal, dok su fenolna jedinjenja detektovana u hidrofilnim ekstraktima (hidroksicinamati, flavonoli i dihidrohalkoni) bila efikasnija u redukciji jona gvožđa. Etanolni ekstrakt tropa paradajza pokazao je inhibitornu aktivnost na angiotenzin-konvertujući enzim pri koncentraciji ekstrakta od 10 mg/ml. Kečap proizveden od svežeg tropa paradajza, kečap proizveden od liofilizata tropa paradajza i marmelada proizvedena od liofilizata tropa paradajza su bili okarakterisani povećanim sadržajem prehrambenih vlakana (preko 3 g na 100 g proizvoda), na osnovu kog mogu da se deklarišu kao izvor vlakana. Marmelada je proizvedena od liofilizovanog tropa paradajza bez dodatka hidrokoloida, sa 20% manjim sadržajem šećera u odnosu na komercijalne proizvode. Reološka svojstva kečapa proizvedenog od svežeg tropa paradajza su prevashodno zavisila od koncentracije nerastvorljivih čestica. Rezultati senzorske ocene sprovedene uz primenu panela treniranih ocenjivača, ukazuju da su miris na paradajz i aroma paradajza bili najvažniji za jasno razlikovanje kečapa proizvedenog od svežeg tropa paradajza od komercijalnih proizvoda. Kečap i marmelada proizvedeni od liofilizovanog tropa paradajza se, kao reološki sistemi, mogu opisati modifikovanom frakcionom Kelvin-Voigt-ovom jednačinom kao viskoelastična tela. Ispitivanje model sistema sastavljenih od različitih odnosa liofilizata tropa paradajza i vode tretiranih na temperaturi od 60°C i 100°C ukazalo je da su vrednosti modula elastičnosti (G’) zavisile od koncentracije liofilizata tropa i da su G’ vrednosti niže na 100°C u odnosu na 60°C. Test dopadljivosti kečapa i marmelade od liofilizovanog tropa paradajza, sproveden primenom hedonske skale od 1 do 7, ukazuje da su oba proizvoda prihvaćena od strane potrošača (prosečna ocena za ukupnu dopadljivost veća od 4).This dissertation describes processes for utilization of tomato processing byproduct (tomato pomace) as raw material for value-added food products. Research was conducted in two directions: one is production of lipophilic and hydrophilic tomato pomace extracts using solvents that are allowed for use in the food industry (n-hexane and 95% ethanol) and their characterization in terms of content and composition of phytochemicals and their in vitro biological activity; the other one is development of formulations and technological processes for the creation of tomato pomace based products with increased content of dietary fiber and their characterization in terms of nutritional, rheological and sensory properties. Three products with increased dietary fiber content were produced: ketchup was produced from fresh tomato pomace, and ketchup and jam were produced from lyophilized tomato pomace powder. Produced lipophilic and hydrophilic extracts showed ferric ion reducing ability, as well as DPPH, nitric oxide and superoxide anion radical scavenging activity. Carotenoids detected in lipophilic extracts (lycopene and β-carotene) were correlated with higher superoxide anion radical scavenging activity, while phenolic compounds detected in hydrophilic extracts (hydroxycinnamates, flavonols and dihydrochalcones) were more effective in ferric ion reduction. Ketchup produced from fresh tomato pomace, ketchup produced from lyophilized tomato pomace, and jam produced from lyophilized tomato pomace were characterized by increased content of dietary fiber (more than 3 g per 100 g of product). Jam was produced from the lyophilized tomato pomace without addition of hydrocolloids, with 20% lower sugar content in comparison with commercial products. Rheological properties of ketchup produced from fresh tomato pomace primarily depended on the insoluble particles content. The results of sensory analysis indicate that tomato odor and flavor were the most important for clear separation of ketchup produced from fresh tomato pomace from commercial products. Ketchup and jam produced from lyophilized tomato pomace could be described, as rheological systems, by the application of modified fractional Kelvin-Voigt model as viscoelastic solids. The examination of model systems comprised of different lyophilized tomato pomace:water ratios heat treated at 60°C and 100°C indicated that storage modulus (G’) values depended on the concentration of lyophilized tomato pomace and that G’ values were lower at 100°C than at 60°C. Preference test for ketchup and jam, conducted by application of 7-point hedonic scale, indicated that both products were accepted by the consumers (average score for overall acceptability higher than 4)

Benefits and Limitations of Lab-on-a-Chip Method over Reversed-Phase High-Performance Liquid Chromatography Method in Gluten Proteins Evaluation

RP-HPLC (reversed-phase high-performance liquid chromatography) is widely used to determine the amounts of the different gluten protein types. However, this method is time-consuming, especially at early stages of wheat breeding, when large number of samples needs to be analyzed. On the other hand, LoaC (Lab-on-a-Chip) technique has the potential for a fast, reliable, and automatable analysis of proteins. In the present study, benefits and limitations of Lab-on-a-Chip method over RP-HPLC method in gluten proteins evaluation were explored in order to determine in which way LoaC method should be improved in order to make its results more compliant with the results of RP-HPLC method. Strong correlation (P lt = 0.001) was found between numbers of HMW glutenin peaks determined by LoaC and RP-HPLC methods. Significant correlations (P lt = 0.05) were obtained between percentages of HMW and LMW glutenin subunits calculated with regard to total HMW + LMW area. Even more significant correlation (P lt = 0.001) was found when percentages of individual HMW areas were calculated with regard to total HMW. RP-HPLC method showed superiority in determination of gliadins since larger number and better resolution of gliadin peaks were obtained by this method

Quality of Root Vegetables during Prolonged Storage

The objective of this study was to develop postharvest techniques and technologies of the most important root vegetables: carrots, celeriac and parsnip. Investigations included the effect of harvest maturity (harvest at November or January) and postharvest washing treatments (hot water, H2O2 and NaOCl and non-washed-control) of carrots (Daucus carota ’Bolero F1’), parsnip (Pastinaca sativa ‘Banatski dugi’) and celeriac (Apium graveolens var. rapaceum ‘Mentor’) roots and effects on their quantitative and qualitative changes during different storage conditions (S-1; 0°C and 98% RH or S-2; 0-2°C and 85-92% RH). Water loss and quality changes in these vegetables roots were monitored after 120 and 180 days of storage period (SP). At the end of SP the percentage of water loss ranged from 3.20% (from first harvest inside the S-1 with H2O2 treatment) in carrot to 39.29% (from first harvest inside the S-2 in control) in celeriac root. The dry matter content (DM) increased during storage period. Total sugar content (TSC) in the roots depends on year and harvest time. During SP, total sugar content increased more in S-2 cooling room. The parsnip root was characterized by more hardness texture relative to the carrot and celeriac roots. During SP carrot root loses the flexibility. The most effective method of maintaining quality of root vegetables is optimal harvest time followed by prestorage washing treatments (H2O2 or NaOCl) and storage at optimum temperature (0 ºC) with a high relative humidity 98%

The effects of wheat cultivars on the production of different types of wheat flours of precisely defined magnesium content

Whole kernels of cereals are the most important source of magnesium. This mineral has several positive effects on human health. However, the human body cannot absorb 100% of magnesium from plant sources during digestion. Additionally, the wheat flour milling process usually produces refined flour with a substantially lower content of magnesium. The aim of this study was to examine the effect of milling of two wheat cultivars on total and soluble magnesium distribution in milling fractions, with the purpose of creating wheat bread with a precisely defined magnesium content. Ash content, thousand grain weight (TGW), and kernel size were analysed in five wheat cultivars. Two most statistically distinguished wheat cultivars according to these analyses (Moma and Todorka) were milled in a laboratory mill to gain as many flour frac-tions as possible (eleven). Magnesium was extracted from the flour and its content was measured by inductively coupled plasma. The results showed that the level of soluble magnesium in refined white flours (T-500 with ash content between 0.46-0.60d. m.%) is approximately 17% and is available for uptake in the human body. Also, by milling the Moma cultivar in an industrial mill with a capacity of 100 t per day gave 6.6 t more brown flour (T-1000 with ash content between 1.05-1.15 d.m.%) than the Todorka cultivar. Furthermore, the daily consumption of brown bread (produced from brown flour) in Serbia would satisfy about 60% of the daily magnesium requirements

Kinetika fermentacije i fizičkohemijske karakteristike specijalnih piva sa dodatkom grožđa sorte Prokupac

Over the last decade, the market of special beers with improved healthy function and/or with new refreshing taste has significantly increased. One of the possible solutions enables mixing beer with bioactive components in grapes responsible for well-known health-promoting action of red wine. The effects of the addition of the Prokupac grape on the physicochemical properties and the fermentation kinetics of the grape beer were studied and the results were compared with a control lager beer. The effect of grape addition on the activity of yeast was also studied. Original extract, alcohol content, degree of fermentation, fermentation rate and yeast growth were significantly higher in beers with grapes as a consequence of higher concentration of simple sugars in grapes compared with pure wort. Based on the CIELab chromatic parameters the color of grape beer samples was yellow with certain proportion of redness, while the control beer was purely yellow. The increase in the concentration of grape mash affects the reduction of lightness and yellowness of beers, while the redness of samples was directly proportional with grape quantity. The phenolic content and antioxidant capacity of grape beers was remarkably higher compared to the control beer, which indicates that the grape beer is a better source of natural antioxidants than regular lager beer.Poslednjih godina, tržište specijalnih vrsta piva koja se odlikuju poboljšanom zdravstvenom funkcijom i/ili novim osvežavajućim ukusom se značajno povećalo. Jedna od mogućnosti je i obogaćivanje piva sa bioaktivnim jedinjenjima grožđa koja su odgovorna za dobro poznato blagotvorno dejstvo crvenih vina na zdravlje. U radu je ispitivan uticaj dodatka grožđa sorte Prokupac na fizičkohemijske karakteristike i kinetiku fermentacije specijalnih piva sa dodatkom grožđa, pri čemu su dobijeni rezultati poređeni sa kontrolnim lager pivom. Uticaj dodatka grožđa na aktivnost kvasca je takođe ispitivan. Početni ekstrakt, sadržaj alkohola, stepen prevrelosti, brzina fermentacije i razmnožavanje kvasca je bilo značajno veće kod piva sa dodatkom grožđa, zbog većeg sadržaja prostih šećera u grožđu u poređenju sa čistom sladovinom. Prema CIELab parametrima boje, boja piva sa dodatkom grožđa je bila žuta sa određenim udelom crvene, dok je kontrolno pivo bilo čiste žute boje. Povećanjem udela grožđa boja piva postaje tamnija i sa manjim udelom žute boje, dok je udeo crvene boje direktno proporcionalan sadržaju grožđa. Sadržaj fenolnih jedinjenja i antioksidativni kapacitet piva sa dodatkom grožđa je bio značajno veći u odnosu na kontrolno pivo, što znači da je pivo sa grožđem bolji izvor prirodnih antioksidanasa nego komercijalno lager pivo

Volatile Composition, Colour, and Sensory Quality of Spirit-Based Beverages Enriched with Medicinal Fungus Ganoderma lucidum and Herbal Extract

The multicomponent mixtures consisting of herbs and fungi are commonly used for the production of alcoholic beverages with potential health-promoting effects in many Asian countries. The medicinal fungus Ganoderma lucidum is one of the most important fungi used for spirit production. Although this fungus affects the aromatic complexity of spirits, only a small number of studies have focused on investigating the influence of G. lucidum on the aromatic profile and colour of spirits. The aim of the research is to evaluate the influence of adding G. lucidum and herbal extract on final concentrations of volatile compounds and sensory quality of several distillates. In this study, distillates (grain, plum, grape and wine) were used to produce new spirit-based beverages with the fungus G. lucidum only, or with the fungus and herbal extract. Fifty-nine aroma compounds were identified by GC-MS. The aromatic profiles were strongly influenced by the primary aromas of the distillates, but the addition of G. lucidum and herbal extract enriched the volatile fraction of distillates with a range of ethyl esters, with a fruity and floral fragrance. Higher alcohols, 1-propanol, 2-isobutanol and isoamyl alcohol, were the most abundant volatile compounds in the analyzed distillates and spirits. The lightness of distillates was from 60.7 to 63.6, and with the addition of Ganoderma it significantly decreased to the range from 43.6 to 50.5. The addition of the fungus also increased the intensity of red and yellow colours. The Ganoderma spirits scored very highly in sensory evaluation (17.6-18.3), significantly better than the spirits without any additions (16.1-16.9)

Prediction of the genetic similarity of wheat and wheat quality by reversed-phase high-performance liquid chromatography and lab-on-chip methods

The aim of this study was to compare efficiency of RP-HPLC (Reversed-Phase High-Performance Liquid Chromatography) and LOC (Lab-on-Chip) methods for wheat gluten protein quantification regarding clustering of wheat cultivars according to the genetic similarity (HMW-GS combinations), as well as to explore relations of these two methods to wheat quality parameters. For that purpose, wheat quality parameters (protein content, falling number, wet gluten content, gluten index, Farinograph, Extensograph, and Amylograph), as well as amounts of gliadin and glutenin fractions by RP-HPLC and LOC methods were determined in two different sets of wheat cultivars (Croatian and Serbian). The percentages of gluten proteins and the values of quality parameters were used to characterize the samples by principal component analysis (PCA). Gluten protein quantification performed by method based on the protein fraction separation by molecular weights (LOC) was better for grouping of genetically similar wheat cultivars than quantification of proteins separated by their different solubility in specified solvent gradient (RP-HPLC). LOC method showed higher potential in wheat quality prediction

Potencijalna primena sorte tritikalea 'Odisej' u proizvodnji čajnog peciva

Triticale, a hybrid cereal developed by crossing of wheat and rye, has certain advantages over wheat, such as higher environmental tolerance and higher content of dietary fiber. The application of triticale flour in food industry is limited by poor rheological properties of dough and low gluten strength. Potential application of hexaploid triticale cultivar 'Odisej' for the production of cookies was assessed in this study. Additionally, the values of basic grain quality parameters for Odisej were determined, such as hectoliter weight, thousand kernel weight, grain size, protein and wet gluten content, gluten index and falling number. Cookies were prepared from refined and wholegrain triticale flour and their physical properties (dimensions, color, hardness) and sensory properties were compared to the cookies prepared from refined and wholegrain wheat and rye flour. Cookies manufactured from refined triticale flour had high spread ratio (diameter/high) value, similar to that of cookies prepared from refined wheat flour. Total sensory score of cookies manufactured from refined triticale flour was the highest among all samples, indicating that it can be successfully used in cookies production.The quality of wholegrain triticale cookies could be improved by the use of milling technique adequate for the production of wholegrain flour.Tritikale, hibridna žitarica dobijena ukrštanjem pšenice i raži, ima određene prednosti u odnosu na pšenicu, kao što su veća otpornost prema uslovima sredine i veći sadržaj prehrambenih vlakana. Primena brašna tritikalea u prehrambenoj industriji ograničena je lošim reološkim svojstvima testa i slabim glutenom. U ovoj studiji istražena je potencijalna primena heksaploidne sorte tritikalea "Odisej" u proizvodnji čajnog peciva. Pored toga, utvrđene su vrednosti osnovnih pokazatelja kvaliteta zrna (hektolitarska masa, masa 1000 zrna, veličina zrna, sadržaj proteina i vlažnog glutena, gluten indeks i broj padanja) za sortu "Odisej". Čajna peciva su pripremljena od belog i integralnog brašna tritikalea, a njihova fizička svojstva (dimenzije, boja, tvrdoća) i senzorska svojstva upoređena su sa čajnim pecivima pripremljenim od belog i integralnog pšeničnog i raženog brašna. Čajna peciva proizvedena od belog brašna tritikalea imala su vrednost odnosa širenja (prečnik/visina) sličnu vrednosti dobijenoj za čajno pecivo od belog pšeničnog brašna. Zbirna ocena senzorskog kvaliteta čajnog peciva proizvedenog od belog brašna tritikalea bila je najveća među svim uzorcima, što ukazuje da se belo brašno tritikalea može uspešno koristiti u proizvodnji čajnog peciva. Kvalitet čajnog peciva od integralnog brašna tritikalea mogao bi da se poboljša primenom tehnike mlevenja koja je adekvatna za proizvodnju integralnog brašna

Reološka svojstva prosenog testa pripremljenog sa različitim proteinima

Millet (Panicum miliaceum L.) flour represents potential raw material for the production of gluten-free products. Since bread of satisfactory quality cannot be produced using pure millet flour, various structuring agents are used to improve its textural properties, such as different hydrocolloids, starches and proteins. Proteins from different sources have been chosen for this study because they are not considered as additives (do not possess E-number). Additionally, they improve nutritional profile of millet bread since millet flour has low protein content. Four types of proteins were used for the production of millet bread: pea protein concentrate, rice protein concentrate, pumpkin oil cake protein isolate and whey protein concentrate. Bread formulation consisted of millet flour, sugar, yeast, salt and water (110 % of hydration on the millet flour basis). Proteins were used to substitute 10 % of millet flour in bread formulation. Dough prepared without addition of yeast was used for the determination of rheological properties to avoid their change during fermentation. Small deformation dynamic oscillatory measurements of doughs were performed using a Haake MARS rheometer (Thermo Scientific, Karlsruhe, Germany) at temperature of 25 °C, equipped with a parallel plate geometry PP60 (60 mm diameter and 1 mm gap). Dough was left to rest 300 s before measurement. Frequency sweep (mechanical spectrum) was recorded over the range of 0.1 - 10 Hz at 0.1 Pa stress, which was within the linear viscoelastic region as previously determined by stress sweep test.Proseno (Panicum miliaceum L.) brašno predstavlja potencijalnu sirovinu za proizvodnju bezglutenskih proizvoda. Pošto je nemoguće proizvesti hleb zadovoljavajućeg kvaliteta od čistog prosenog brašna, koriste se različiti agensi za poboljšanje njegovih teksturnih svojstava, kao što su različiti hidrokoloidi, skrobovi i proteini. Proteini iz različitih izvora odabrani su za ovu studiju zato što se ne smatraju aditivima (nemaju E-broj). Pored toga, proteini poboljšavaju nutritivni profil prosenog hleba jer proseno brašno ima nizak sadržaj proteina. Četiri vrste proteina korišćene su u proizvodnji prosenog hleba: koncentrat proteina graška, koncentrat proteina pirinča, izolat proteina uljane pogače bundeve i koncentrat proteina surutke. Formulacija hleba sastojala se od prosenog brašna, šećera, kvasca, soli i vode (110% hidratacije na bazu prosenog brašna). Proteini su korišćeni za supstituciju 10% prosenog brašna u formulaciji hleba. Testo pripremljeno bez dodatka kvasca korišćeno je za određivanje reoloških svojstava da bi se izbegle promene prilikom fermentacije. Dinamička oscilatorna merenja pri malim deformacijama izvedena su korišćenjem Haake MARS reometra (Thermo Scientific, Karlsruhe, Germany) na temperaturi od 25°C, uz upotrebu pribora tipa ploča-ploča PP60 (60 mm prečnik ploče i 1 mm zazor između ploča). Testo je ostavljeno da odmara 300 s pre merenja. Test pri promeni frekvencije (mehanički spektar) je snimljen u opsegu frekvencija od 0,1 do 10 Hz pri naponu smicanja od 0,1 Pa, za koji je prethodno utvrđeno u testu sa promenom napona de se nalazi unutar viskoelastičnog područja

Multivariate analysis of tomato genotypes based on morphological and chemical fruit properties

In recent decades the importance of tomato considered as “functional food” is reflected in the rising trend of harvested areas and consumption per capita. During three consecutive years (2010-2012) at experimental fields in Rimski Šančevi near Novi Sad, five landraces, four old varieties, eight breeding lines and three commercial cultivars were chosen for the investigation. Following fruit characteristics were analyzed: average weight (g), length (cm), width (cm), pericarp thickness (mm), locule number, moisture content (%), total soluble solids (°Brix), ash content (%), total acidity (%) and pH value. For the most fruit characteristics high variability was determined. Four principal components explained 90,6% of total variance or 36.5%, 24.2%, 19.8% and 10.1, respectively. Along the axis of the first main component, genotypes were classified into three groups. The objective of this study was to classify 20 tomato genotypes based on physical and chemical traits and to segregate perspective genotypes for improvement of tomato quality by breeding programs