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Strawberries are a nonclimacteric fruit characterized by a short postharvest life that limits their marketing. They are susceptible to mechanical injury, drying, decay and physiological disorders during storage. Altough the grey mold and Rhizopus rot are two main pathogens infections from Penicillium ssp. (blue mold) also occus occasionally. In this study, effect of preharvest (non) fungicide treatment and postharvest treatment on decay development and quality parameters was studied. Strawberries of the cultivar Clery were harvested in the eastern Slovenia at red ripe maturity stage. Plants were grown inside the tunnels or outside (without any proection). Fruits were further grouped according to the different cultivation techniques (integrated pest management, ecological farming or non fungicide treatment)and stored under normal or modified atmosphere (Xtend)at 1oC for 7 days. In second experiment, non sprayed, in tunnel grown strawberries were subjected ti the chitosan dip treatment, with or without the addition of ascorbic acid and stored under normal atmosphere for 14 days. Based on the results obtained, for the outside cultivation the use of pesticides was required, otherwise the crop failure was more than 50 % after one week storage. On the other hand, in tunnels, where strawberries were produced with ecological fungicide or even without any pesticides, the decay development was still well reduced. Futher, modified atmosphere did not extend strawberrie's shelf life or improve their quality. On the contrary, the use of chitosan was effective, after two weeks of storage experiment the decay was reduced for around 20% when compared to the control. Chitosan was more effective without ascorbic acid. After decay evaluation, compositional changes were estimated. According to our investigation, the content of total soluble solids and total acids were practically constant throughout the storage. With the exception of strawberries from integrated farming, which were grown in tunnel, there were no significant differences between tested groups. Furthermore, it seems like the modified atmosphere did not affect those values either. The vit C was negatively affected during storage and also determined by cultivation type, the highest contents were achieved for integrated pest management regardless were they were grown. On the contrary, different preharvest pesticeds treatments did not significantly affect the aroma profile of strawberries. Ethyl acetate, ethanol, ethyl butanoat, butyl acetate, ethyl hexanoat, hexyl acetat and acetic acid increased during storage, while nerolidol, ethyl hexanoat, metil butanoat, 2-methyl-ethyl-butanoat and buthyl butanoat decreased during storage. Even after 4 days of storage, there were still traces of fludioxonil and fenhexamide in strawberries from integated farming, meanwhile cypronidil was not found in any sample. Finally, all tested samples were negative for patulin and ochratoxin analysis.

Biodegradable coatings applied to fruits are environmentally friendly and healthy treatments, which preserve fresh fruit quality and safety during postharvest storage. The objective of this research was to investigate the effect of a postharvest treatment with chitosan and chitosan with ascorbic acid on polyphenols and antioxidant activity in strawberries stored at 2°C, for 14 days.Strawberry fruit cv. „Clery“ were obtained from an organic tunnel crop production system located in Maribor, Slovenia. Fruits were coated with 1% chitosan and chitosan with 0.5 % ascorbic acid. Non treated fruits represented control group. During storage time strawberries were sampled after 0, 2, 4, 7, 9, 11, 14 days and spectrometrically analyzed for total phenolic and flavonoid content, total anthocyanins, and antioxidant activity using DPPH assay.Results were statistically analysed using Duncan's multiple range test.Concentrations of total phenols were higher in control samples than in treated ones.Total flavonoid content differed significantly between chitosan and chitosan with ascorbic acid treatment, first one having the higher concentration, but both treatments did not differ significantly compared to control sample. Anthocyanin content and antioxidant activity differed significantly among applied treatments, with control sample having the highest concentration, followed by sample treated with chitosan and combination of chitosan and ascorbic acid. The influence of storage time was especially apparent in control samples where all determined compounds as well as antioxidant activity increased over storage time. In samples treated with both chitosan and combination of chitosan and ascorbic acid there was no regular pattern of storage days influence. In conclusion, both chitosan treatments delayed ripening as reflected in retarded synthesis of anthocyanins, flavonoids, total phenols and antioxidant potential.

Namen diplomskega dela je bil preučiti, kako spreminjanje pogojev slajenja ječmena vpliva na kakovost kongresne sladice. Spreminjajoči dejavniki so bili temperatura (T) namakanja, odsotnost prezračevanja med namakanjem, čas in T kaljenja ter čas in T sušenja. V okviru diplomskega dela smo iz predhodno zaslajenega ječmena pripravili kongresne sladice, ki smo jih ovrednotili z določanjem ekstrakta, časa zasladitve, vrednosti pH, dinamične viskoznosti, vsebnosti prostega aminokislinskega dušika (FAN), vsebnosti skupnih fenolov in skupnih flavonoidov ter z določanjem sposobnosti lovljenja DPPH• radikala. Ugotovili smo očiten vpliv T namakanja, kaljenja in sušenja na kakovost kongresnih sladic. Stalna T namakanja in kaljenja je rezultirala v manjši akumulaciji (pri 10␃) ali izgubah (pri 20␃) ekstrakta in FAN v sladu, medtem ko so se kombinacije (nižja T namakanja + višja T kaljenja ali pa kombinacija nižje in višje T v času kaljenja) izkazale kot boljši režimi. Višje T sušenja so vodile do večjih izgub ekstrakta in FAN, a hkrati povečale vsebnost skupnih fenolnih spojin in flavonoidov ter antioksidativno učinkovitost. Krajši čas kaljenja je splošno vplival na slabše rezultate, za daljši čas kaljenja pa ne moremo z gotovostjo potrditi vpliva na izboljšanje rezultatov. The aim of diploma thesis was to investigate the impact of malting conditions on the Congress wort quality. The changing parameters were steeping temperature, lack of aeration during steeping, duration and temperature of germination and duration and temperature of kilning. Congress worts were prepared from pre-malted barley and were evaluated by determining the extract content, the time of starch convertion into sugars, the pH value, the dynamic viscosity, the free amino nitrogen (FAN) content, the total phenol and the total flavonoid content as well as the DPPH• radical scavenging ability. We found a significant effect of steeping, germination and kilning temperatures on the quality of Congress worts. A constant temperature of steeping and germination resulted in lesser accumulation (10␃) or greater losses (20␃) of extract and FAN content in malt, while their combinations (lower T of steeping + higher T of germination or a combination of lower and higher T in time of germination) were found to be better regimes. Higher kilning temperatures resulted in greater losses of extract and FAN, but at the same time increased the content of total phenolic compounds and flavonoids as well as antioxidant activity. A shorter germination time generally led to poorer results, meanwhile we could not directly confirm the positive effect of a longer germination time.

V doktorski disertaciji smo preučili vpliv različnih biotehnoloških procesov (kaljenja, fermentacije, encimske obdelave) na vsebnost in dostopnost ekstraktibilnih in vezanih fenolnih spojin v semenih pire in na njihovo in vitro ter in vivo antioksidativno aktivnost. Glavne identificirane fenolne spojine v pirinih semenih so bile ferulna, p-kumarna, kavna in p-hidroksibenzojska kislina. Pri iskanju optimalnih pogojev abiotskega stresa med kaljenjem semen za čim večji prirast fenolov, je kaljenje pri povečani slanosti in osmolarnosti brez aplicirane mehanske poškodbe najbolj povečalo vsebnost fenolnih spojin in izboljšalo njihovo antioksidativno aktivnost. Kombiniranje različnih biotehnoloških procesov predstavlja bistveno učinkovitejši način za povečanje vsebnosti fenolnih spojin kot posamezen proces. Največjo absolutno vsebnost ekstraktibilnih in vezanih posameznih fenolnih kislin smo določili v kaljenih semenih, fermentiranih s S. cerevisiae. Nadalje je obdelava kaljenih in fermentiranih semen s petimi hidrolitičnimi encimi znatno povečala vsebnost ekstraktibilnih fenolnih spojin, hkrati pa je imela negativen vpliv na vsebnost vezanih fenolnih spojin. Fenolne spojine iz kaljenih semen niso zaščitile modelnega organizma S. cerevisiae pred oksidacijo, medtem ko je večina ekstraktibilnih fenolnih spojin iz fermentiranih in encimsko obdelanih semen znižala znotrajcelično oksidacijo. Večji celični privzem fenolnih spojin ne pomeni nujno tudi večje antioksidativne aktivnosti in vivo, poleg količine je pomembna tudi oblika fenolnih spojin, ki vstopajo v celico. Rezultati kažejo na spremembe v sestavi ekstraktov med simulirano in vitro prebavo, saj so antioksidanti istega ekstrakta pokazali drugačen odziv proti različnim prostim radikalom v primerjavi z neobdelanimi semeni. Največjo vsebnost biološko dostopnih fenolnih spojin smo ugotovili v kaljenih semenih, fermentiranih s S. cerevisiae. Izgube fenolnih spojin po prebavi so bile velike, kljub temu pa so biološko obdelana semena imela še vedno znatno večjo vsebnost fenolnih spojin v primerjavi z neobdelanimi semeni. Within the scope of the doctoral dissertation, we investigated the influence of different biotechnological processes (germination, fermentation, enzymatic treatment) on the content and accessibility of extractable and bound phenolic compounds in spelt seeds, as well as on their antioxidant activity in vitro and in vivo. The major phenolic compounds identified in spelt seeds were ferulic, p-coumaric, caffeic and p-hydroxybenzoic acids. When searching for the optimal conditions of abiotic stress during seed germination to produce the greatest increase in phenolics, germination at increased salinity and osmolarity without applied mechanical damage showed the highest increase in phenolic compounds content and antioxidant activity. Combining different biotechnological processes represents the more effective way to increase the content of phenolic compounds than a single process. The highest absolute content of extractable and bound individual phenolic acids was found in germinated seeds fermented with S. cerevisiae. Moreover, treatment of germinated and fermented seeds with five hydrolytic enzymes significantly increased the content of extractable phenolic compounds, but at the same time had a negative effect on the content of bound phenolic compounds. Phenolic compounds of germinated seeds could not protect the model organism S. cerevisiae from oxidation, whereas most extractable phenolic compounds from fermented and enzymatic treated seeds reduced intracellular oxidation. Greater cellular uptake of phenolic compounds does not necessarily mean greater antioxidant activity in vivo, in addition to the quantity, the form of phenolic compounds entering the cell is also important. The results suggest changes in the composition of the extracts during simulated in vitro digestion, since antioxidants of the same extract showed a different response against various free radicals compared to the raw seeds. The highest content of bioaccessible phenolic compounds was found in germinated seeds fermented with S. cerevisiae. Losses of phenolic compounds after digestion were high, however, the bioprocessed seeds still contained higher content of phenolic compounds compared to raw seeds.

V sklopu magistrskega dela smo želeli preučiti vpliv kaljenja, namakanja, sušenja in kuhanja zrn na vsebnost nekaterih pomembnih komponent ajde, kvinoje in amaranta. V metanolnih ekstraktih smo določili vsebnost prostih fenolov in topnih konjugatov, za določanje vsebnosti vezanih fenolov pa je bila potrebna predhodna alkalna hidroliza rastlinskega matriksa. Posamezne frakcije fenolov smo ovrednotili s pomočjo Folin-Ciocalteujeve metode ter metode DPPH. Vsebnost fitinske kisline smo določili s pomočjo spektrofotometrične metode, za določanje vsebnosti topne in netopne prehranske vlaknine pa smo uporabili encimsko-gravimetrično metodo AOAC 991.43. Med preizkušenimi postopki bi pri vseh treh psevdožitih izpostavili 96 h kaljenje, ki je v zrnih znatno izboljšalo vsebnost in ekstraktibilnost celokupnih fenolov, njihov antioksidativni potencial ter najbolj pripomoglo k hidrolizi fitinske kisline. Kaljenje je precej povečalo vsebnost skupne prehranske vlaknine v ajdi in izboljšalo razmerje med topno in netopno frakcijo. Nadalje bi priporočali tudi 120 min sušenje zrn v pečici, zlasti v primeru prehranske vlaknine v amarantu in zmanjšane vsebnosti fitinske kisline v ajdi in kvinoji. Omenjen režim je precej doprinesel tudi k povečanju vsebnosti celokupnih fenolov in izboljšanju učinkovitosti antioksidantov v vseh treh vrstah psevdožit. Namakanje zrn v vodi se je izkazalo kot nekoliko manj primeren postopek, optimalni pogoji so bili odvisni od vrste psevdožita in preiskovanih parametrov. Kuhanje zrn je praviloma imelo negativen vpliv na večino analiziranih parametrov vseh treh psevdožit in ga zato odsvetujemo. The aim of the study was to analyse the respective impacts of germination, soaking, drying and cooking of grains on the nutritional components of buckwheat, quinoa and amaranth. Methanol extracts were utilised to determine the contents of free phenolic compounds and soluble conjugates, whilst alkaline hydrolysis of the sample plant matrix was necessary for the determination of bound phenolics content. Individual fractions of phenolics were evaluated using the Folin-Ciocalteu and DPPH assays, respectively. The content of phytic acid was determined with spectrophotometric method. The enzyme-gravimetric method AOAC 991.43 was used for the determination of soluble and insoluble dietary fibre contents. Amongst the preparation techniques of all three pseudocereals, the 96-hour germination is to be highlighted, as it substantially improved the content and extractability of total phenolics, their antioxidant potential and most contributed to the hydrolysis of phytic acid. Germination considerably increased the content of total dietary fibre in buckwheat grains and improved the ratio between the soluble and insoluble fractions. Furthermore, the study found that the process of drying the grains in the oven for 120 minutes is beneficial, which is particularly evident in the case of the dietary fibre of amaranth grains, and the decreased content of phytic acid in buckwheat and quinoa. The regimen also benefited in increasing contents of total phenolics and the efficacy of antioxidants in all three sorts of pseudocereals. Soaking of grains in water resulted as slighty less suitable technique as optimal conditions varied between the given pseudocereals and the analysed parameters. Cooking of grains had a negative impact on most of the investigated parameters and is therefore not recommended.

Namen diplomskega dela je s pregledom strokovne literature raziskati bioaktivne komponente iz žit, njihov vpliv na zdravje in možnosti za njihovo vključitev v funkcionalna živila. Funkcionalna živila so tista, ki v večji meri izkazujejo ugoden fiziološki učinek ali zmanjšano tveganje za kronične bolezni kot osnovna živila. V žitih najdemo veliko bioaktivnih komponent, ki pozitivno vplivajo na zdravje, senzorične in tehnološke lastnosti, kot so polifenolne spojine, vitamini, prehranska vlaknina in njene funkcionalne komponente – arabinoksilani, β-glukani, rezistentni škrob. Naštete bioaktivne komponente imajo antihiperzitivne, protimikrobne, prebiotične, probiotične, antioksidativne, protivnetne in imunomodulatorne lastnosti ter zmanjšujejo pojavnost bolezni srca in ožilja, sladkorne bolezni tipa 2, debelosti in raka. Naštete bioaktivne komponente ugodno vplivajo tudi na tehnološke lastnosti živil, saj služijo kot stabilizatorji, zgoščevalci, emulgatorji in nadomestki maščob. Ob vključitvi v funkcionalno živilo omogočajo izboljšavo hranilne vrednosti, kot je povišana vsebnost prehranske vlaknine ali zmanjšana vsebnost maščob, ter tehnoloških lastnosti, kot je izboljšan volumen izdelka in izboljšana tekstura, z minimalnim vplivom na senzorično vrednost. Neustrezen, tj. prevelik dodatek žitnih bioaktivnih komponent lahko vodi v preveč viskozen izdelek, ki ima majhen volumen, je trd, ima slabšo barvo in teksturo ali v živilu povzroči pojav nezaželenega okusa in arom. The aim of the thesis is to investigate the bioactive components of cereals, their impact on health and potential for their incorporation in functional foods by reviewing the literature. Functional foods are those that have beneficial physiological effect or reduced risk of chronic diseases compared to staple foods. Cereals contain many bioactive components that have a positive effect on health, sensory and technological properties, such as polyphenolic compounds, vitamins, dietary fiber and its functional components - arabinoxylans, β-glucan, and resistant starch. The listed bioactive components have antihypertensive, antimicrobial, prebiotic, probiotic, antioxidant, anti-inflammatory and immunomodulatory properties and reduce the incidence of cardiovascular diseases, type 2 diabetes, obesity and cancer. The listed bioactive components have a positive effect on the technological properties of foods, serving as stabilizers, thickeners, emulsifiers and fat substitutes. When included in a functional food, they enable the improvement of nutritional value, e.g., increased dietary fiber content or reduced fat content, and technological properties, e.g., improved product volume and texture, with minimal impact on its sensory value. Inappropriate, i.e., too large addition of cereal bioactive ingredients may result in a product with high viscosity, low volume, high strength, poor color and texture, and the appearance of undesirable taste and flavors.

V izvedbo magistrskega dela smo vključili 11 slovenskih sort hmelja in jih primerjali z znano nemško sorto Magnum. Iz hmeljnih briketov smo pri temperaturi 40 °C pripravili etanolne ekstrakte in jim določili vsebnost skupnih fenolnih spojin (SFS), skupnih flavonoidov (SF) in njihovih podskupin (flavonov in flavonolov (FF), flavanonov in dihidroflavonolov (FDH)) ter antioksidativni potencial (AOP). Zanimala nas je tudi korelacija med sorto hmelja in učinkovitostjo prehajanja SF, SFS, FF in FDH v pivo. V pivu smo določali še vsebnost alfa- in beta-kislin. Od slovenskih sort po vsebnosti SF, SFS in FF izstopa sorta Wolf. Več SF in SFS kot Magnum vsebujejo še sorte Fox, Aurora in Cardinal. Kolibri, Savinjski golding in Dragon so sorte z najmanjšo vsebnostjo SF in SFS. Najvišji AOP imajo sorte Dana, Gold in Aurora, medtem ko najnižji Savinjski golding. Daljši čas hladnega hmeljenja ugodno vpliva na večjo izluženost SF, SFS, FF in FDH v pivu, negativno pa na AOP piva. Največ SF so po sedmih dneh vsebovala piva hmeljena s sortami Wolf, Savinjski golding ali Bobek. Sorta Dana je po dodatku v pivo dala slabši rezultat kot Magnum. Po vsebnosti SFS in FF je izstopalo pivo s sorto Wolf. Največji prirast FDH smo potrdili pri pivu s sorto Aurora, najmanjši pri sorti Celeia. Pivu s sorto Dana smo določili enega najvišjih AOP. Najnižji AOP smo po sedmih dneh hmeljenja določili pivu z nemško sorto Magnum. Daljši čas hmeljenja je na večjo izluženost izo-alfa kislin vplival le pri štirih sortah: Wolf, Dragon, Aurora, Fox. Po enem dnevu hmeljenja smo največ kohumulona določili pivu s sorto Cardinal, največ n+adhumulona pivu s sorto Magnum, ksantohumola pa pivu s sorto Wolf vsi trije parametri so s časom hmeljenja pri omenjenih sortah postopoma upadli. In our master's thesis, we included 11 Slovenian hop varieties and compared them with the known German variety Magnum. Ethanol extracts were prepared from hop briquettes at 40°C and the content of total phenolic compounds (SFS), total flavonoids (SF) and their subclasses (flavones and flavonols (FF), flavanones and dihydroflavonols (FDH)) and antioxidant potential were determined (AOP). We were also interested in the correlation between hop variety and the efficiency of transfer of SF, SFS, FF and FDH into the beer. The content of alpha- and beta- acids was also determined in the beer. Among the Slovenian varieties, the Wolf variety stands out in terms of the content of SF, SFS and FF. Fox, Aurora and Cardinal also contain more SF and SFS than Magnum. Kolibri, Savinjski golding and Dragon are the varieties with the lowest content of SF and SFS. Dana, Gold and Aurora have the highest AOP, while Savinjski golding has the lowest. A longer period of dry hopping has a positive effect on the higher content of SF, SFS, FF and FDH in the beer and a negative effect on the AOP of the beer. After seven days of hopping, beers with the varieties Wolf, Savinjski golding and Bobek contained the most SF, meanwhile variety Dana resulted in lower values than Magnum. In terms of SFS and FF content, beer made with Wolf stood out. The highest increase in FDH content was found in beer with the Aurora variety, and the lowest with the Celeia variety. We determined one of the highest AOPs for beer with the Dana variety. After seven days of hopping, the lowest AOP was determined for beer with the German variety Magnum. Longer hopping time influenced the higher transfer of iso-alpha acids only in 4 varieties (Wolf, Dragon, Aurora, Fox). The highest cohumulone in beer was determined after one day of hopping for Cardinal, the most n + adhumulone for Magnum and xanthohumol for Wolf all three parameters gradually decreased with time of hopping.

Kakovost svetlobe vpliva na številne fiziološke procese plodov pred in po obirnaju. V sadovnjaku spekter in intenzivnost sončne svetlobe vplivata na barvo plodov, ki je eden najpomembnejših parametrov kakovosti sadja. Za zagotavljanje visoke kakovosti sadja se svetloba v sadovnjakih uravnava z odsevnimi folijami pod drevesi in barvnimi mrežami za senčenje. Plodovi sadja se odzivajo tudi na obsevanje po obiranju s svetlobo različnih valovnih dolžin. Izkazalo se je, da obsevanje z modro svetlobo po obiranju aktivira fenilpropanoidno metabolno pot, ki inducira sintezo antocianinov in drugih fenolnih spojin, kar povzroči intenzivnejšo rdečo barvo. Glede zorenje plodov, modra svetloba pospeši dihanje in izločanje etilena. Poleg indukcije fenolnih spojin, modra svetloba deluje protimikrobno z aktivacijo reaktivnih kisikovih zvrsti, hidroksilnih radikalov, superoksidnih anionov in prostega kisika. V zadnjem času UV-C svetloba postaja alternativa dezinfekciji sadja in zelenjave po obiranju. Raziskave so pokazale, da UV-C svetloba zavira in upočasni rast mikroorganizmov na površini sadja in zelenjave. Poleg tega UV-C inducira tudi de-novo sintezo fenolnih spojin, s čimer se poveča antioksidativni potencial. V poskusih s sveže rezanim sadjem in zelenjavo UV-C obsevanje uspešno upočasni rast mikrobov in tudi inaktivira encime, vključno s polifenol oksidazo, ki je odgovorna za porjavenje.

Namen magistrskega dela je bil ugotoviti vpliv fermentacije na vsebnost fenolnih spojin, antioksidativni potencial, vsebnost fitinske kisline in vsebnost prehranske vlaknine treh vrst psevdožit. Semena amaranta, kvinoje in ajde smo homogenizirali in fermentirali spontano, s pekovskim kvasom, z dodatkom neaktivnega komercialnega kislega testa in z mešano startersko kulturo LV1 pri izbranih pogojih (24 ali 48 h pri 20 °C oz. 30 °C). Fermentirane vzorce smo liofilizirali in iz njih pripravili metanolne ekstrakte. Fermentacija je vplivala na spremembo vseh analiziranih parametrov. Ti so se spreminjali odvisno od vrste psevdožita, načina in poteka fermentacije. Največji doprinos k vsebnosti fenolnih spojin (FS) in antioksidativnemu potencialu (AOP) amaranta in kvinoje je imela 48 h fermentacija pri 30 °C z dodatkom neaktivnega komercialnega kislega testa. Neodvisno od načina fermentacije smo pri ajdi zabeležili negativen učinek na FS in AOP. Spontana fermentacija, ki je trajala 48 h, je povzročila najbolj obsežno razgradnjo fitinske kisline (FK) pri vseh treh psevdožitih (vsaj 80 %), medtem ko je uporaba neaktivnega kislega testa pri optimalnih pogojih zmanjšala koncentracijo FK za dve tretjini ali več. Vsebnost netopne prehranske vlaknine se je v amarantu in kvinoji med fermentacijo praviloma povečala, v ajdi pa zmanjšala. Delež topne prehranske vlaknine smo v kvinoji in ajdi uspešno povečali zgolj z dodatkom neaktivnega kislega testa, pri različno fermentiranem amarantu smo povsod zabeležili negativen trend. Glede na analizirane parametre bi priporočili pripravo fermentiranih (48 h, 30 °C) psevdožit z dodatkom neaktivnega kislega testa. The aim of the study was to determine the effect of fermentation on the phenolic compounds content, antioxidant potential, phytic acid content and dietary fibre content of three types of pseudocereals. Amaranth, quinoa and buckwheat seeds were homogenized and fermented spontaneously, with baker's yeast, with the addition of an inactive commercial sourdough and with a mixed starter culture LV1 under selected conditions (24 or 48 h at 20 °C and 30 °C, respectively). The fermented samples were lyophilized and methanolic extracts were prepared. Fermentation affected the change in all the parametres analysed. These varied depending on the type of pseudocereal, the method and the course of fermentation. The greatest contribution to the phenolic compound (PC) content and antioxidant potential (AOP) of amaranth and quinoa was obtained by fermentation at 30 °C for 48 h with the addition of an inactive commercial sourdough. Regardless of the fermentation method, a negative effect on PC and AOP was observed in buckwheat. Spontaneous fermentation for 48 h resulted in the most extensive degradation of phytic acid (PA) in all three pseudocereals (at least 80 %), while the use of sourdough at optimum conditions reduced the PA concentration by two thirds or more. The insoluble dietary fibre content generally increased in amaranth and quinoa during fermentation, but decreased in buckwheat. The soluble dietary fibre content of quinoa and buckwheat was successfully increased by the addition of sourdough alone, while a negative trend was observed in all cases with differently fermented amaranth. According to the parameters analysed, we would recommend the preparation of fermented (48 h, 30 °C) pseudocereals with the addition of an inactive sourdough.

Kislo testo pripravimo iz moke in vode s spontano fermentacijo ali z uporabo starterskih kultur. Pri fermentaciji pride zaradi aktivnosti mlečnokislinskih bakterij (z ali brez kvasovk) do sprememb v sestavi testa. Kislo testo ima številne prednosti, vključno s podaljšano trajnostjo, večjim prirastom volumna, upočasnjenim staranjem, izboljšanjem senzoričnih lastnosti in visoko hranilno vrednostjo izdelkov. Fenolne spojine se v kislem testu praviloma nahajajo v vezani obliki, večinoma tvorijo estrske vezi z arabinoksilani in etrske vezi z lignini. Med fermentacijo so mlečnokislinske bakterije v interakciji s prisotnimi fenolnimi spojinami. Struktura, bioaktivnost in biorazpoložljivost slednjih je odvisna tako od žitnih kot mikrobnih encimov: feruloil esteraz, tanaz in glikozil hidrolaz. Mlečnokislinske bakterije so precej odporne na antimikrobno delovanje fenolnih kislin iz pšenice in rži njihova toleranca je delno pogojena z njihovo sposobnostjo, da jih pretvorijo v metabolite s spremenjeno metabolno aktivnostjo. Pozitiven vpliv uživanja fenolnih spojin iz kislega testa na naše zdravje je med drugim odvisen od njihove mikrobne pretvorbe. Hidroksibenzojske in hidroksicimetne kisline se pretvarjajo v ustrezne fenolne in vinilne derivate s pomočjo dekarboksilaz, medtem ko nastanek novih metabolitov omogočajo tudi reduktaze, ki reducirajo hidroksibenzojske kisline in njihove vinilne derivate. Sourdough is prepared from a mixture of flour and water by spontaneous fermentation or by using starter cultures. During fermentation, the dough constituents are modified by the action of the lactic acid bacteria (with or without yeasts). The sourdough fermentation has a number of beneficial effects that include prolonged shelf life, accelerated volume gain, delayed staling, improved sensory characteristics and good nutritional value of products. Phenolic compounds in sourdough are mostly present in bound form through ester bonds to arabinoxylan chain or through ether bonds to lignin. During cereal fermentation, lactic acid bacteria have to interact with inherent phenolic compounds. The latter are modified by the action of both endogenous and bacterial enzymes - feruloyl esterases, tannase, glycosyl hydrolases - thereby affecting their structure, bioactivity and bioavailability. Lactic acid bacteria have a high tolerance to antimicrobial phenolic acids found in wheat and rye their resistance is partially dependent on their capacity to convert phenolic acids to metabolites with changed metabolic activity. Human health benefits associated with the consumption of sourdough phenolic compounds are, in part, depend on microbial conversion. Hydroxybenzoic and hydroxycinnamic acids are converted by decarboxylase to the corresponding phenol or vinyl derivatives. New metabolites are formed also by action of reductases which reduce hydroxycinnamic acids and their vinyl derivatives.

V okviru diplomskega dela smo ugotavljali, kako različni dodatki kaljenih pšeničnih zrn (KPZ) vplivajo na antioksidativne lastnosti kruha. Prvi del poskusa je zajemal pripravo ekstraktov fenolnih spojin (FS) iz predhodno homogeniziranih in liofiliziranih vzorcev kruha z 0 %, 5 %, 15 % in 30 % dodatkom KPZ. Ekstraktibilne FS smo iz kruha pridobili s pomočjo metanola, medtem ko smo vezane FS sprostili iz celičnega matriksa šele po predhodni bazični hidrolizi. Za določanje vsebnosti FS smo uporabili metodo Folin-Ciocalteu (FC), za določanje vsebnosti antioksidantov pa metodi ABTS in DPPH. Z vsemi tremi metodami smo prišli do podobnih rezultatov. V kruhu s KPZ so ne glede na količino dodatka, prevladovali vezani antioksidanti. 15 % dodatek KPZ je vodil v znatno povečanje reaktivnosti ekstraktibilnih (1,9-krat pri metodi FC, 2,6-krat pri metodi ABTS ter 7,4-krat pri metodi DPPH) in vezanih antioksidantov (2,5-krat pri metodi FC in 1,6-krat pri metodi ABTS). Obogatitev kruha s KPZ je praviloma pomenila večji absolutni prirast vezane frakcije in večji relativni prirast proste frakcije antioksidantov. Vsebnost spojin z antioksidativnim delovanjem ni naraščala sorazmerno s količino dodanih KPZ, 30 % dodatka KPZ nismo opravičili. Within the diploma thesis we have studied how different amounts of added germinated wheat grains (KPZ) affect the antioxidant properties of bread. First, the preparation of phenolic compounds (FS) extracts from pre-homogenized and lyophilized bread samples with 0%, 5%, 15% and 30% addition of KPZ were performed. Extractable FS were obtained from bread using methanol, while bound FS were released from the cell matrix after alkaline hydrolysis. The Folin-Ciocalteu (FC) method was used to determine FS content, and the ABTS and DPPH methods for antioxidant determination. Similar results were obtained with all three methods. Bound antioxidants predominated in bread with KPZ, regardless of their amount. A 15% addition of KPZ resulted in considerable enlargement of reactivity of extractable (1.9-fold in the FC method, 2.6-fold in ABTS method and 7.4-fold in DPPH method) and bound antioxidants (2.5-fold in the FC method and 1.6-fold in the ABTS method). Enrichment of bread with KPZ resulted in higher absolute increment of bound and higher relative increments of free antioxidants. The content of the compound with antioxidant activity did not increase in proportion to the amount of added KPZ, supplement of 30% KPZ was not justified.

Namen raziskave je bil ugotoviti, kako kaljenje semen navadnega rička (Camelina sativa L.) vpliva na vsebnost fenolnih spojin in s tem na antioksidativni potencial (AOP) semen. Zanimal nas je vpliv predhodne toplotne obdelave (10 oz. 45 min pri 55 °C) na obseg teh sprememb. Semena smo vzorčili vsakih 24 h po začetku kaljenja. Vzorčena semena smo delno posušili, razmastili s heksanom in iz njih s pomočjo 70 % etanola pridobili ekstrakte fenolnih spojin. Kaljenje je povečalo vsebnosti skupnih fenolnih spojin (SFS), skupnih flavonoidov, flavonov in flavonolov ter flavanonov in dihidroflavonolov. S kaljenjem se je reaktivnost spojin v posameznih testih različno spreminjala, kar nakazuje na kvalitativne in kvantitativne spremembe v sestavi ekstraktov. Kaljenje je povečalo AOP, ki smo ga določili kot sposobnost lovljenja superoksidnega anionskega radikala. Največja vsebnost SFS je bila izmerjena pri 72 urah. Pri 72 urah je bil dosežen tudi največji AOP določen z omenjeno metodo. Toplotna obdelava semen pred kaljenjem praviloma ni vplivala na rezultate. Z opravljeno raziskavo lahko potrdimo delovno hipotezo o povečanju dobiti fenolnih spojin s kaljenjem, hipotezo o vplivu časa kaljenja na vsebnost fenolnih spojin in hipotezo o razlikah v izmerjenem AOP v homogeni raztopini in heterogenem okolju (emulzija linolne kisline v vodi). The aim of the research was to investigate the influence of germination of Camelina sativa L. seeds on the content of phenolic compounds and antioxidative potential (AOP) of the seeds. We also aimed to investigate the influence of thermal treatment (10 or 45 min at 55 °C) of seeds induced before seed germination. The germinated seeds were collected every 24 h, dried, defatted with hexane and extracted with 70 % ethanol. Germination augmented the content of total phenolic compounds, total flavonoids, flavones and flavonols, and flavanones and dihydroflavonols. The reactivity of compounds was changing differently under distinct tests. This implies qualitative and quantitatie changes of the extracts' composition. Germination enhanced AOP measured by capability to scavenge superoxide anions. The maximum content of total phenolic compounds was measured at 72 h. The highest AOP measured by capability to scavenge superoxide anions was at 72 h. In large majority, the heat treatment before germination did not influence the results. With this findings we can confirm our working hypothesis about augmentation of phenolic compounds during germination, hypothesis about influence of time of germination on the content of phenolic compounds and hypothesis about differences in results obtained by measuring AOP in homogeneous solution and in heterogeneous medium (emulsion of linoleic acid in water).

Pira (Triticum spelta) je vrsta žita, ki zadnje čase ponovno pridobiva na veljavi. Z uživanjem celih pirinih zrn poskrbimo za vnos nekaterih pomembnih bioaktivnih spojin in tako pripomoremo k zmanjšanju oksidativnega stresa v telesu. V diplomskem delu smo ugotavljali vpliv dodatka kaljenih pirinih zrn (KPZ) na vsebnost antioksidantov (AO) v kruhu. Vzorce smo analizirali spektrofotometrično z uporabo Folin-Ciocalteu (FC) reagenta, DPPH radikala in ABTS radikala. Rezultate smo izrazili kot ekvivalent klorogenske kisline in ugotovili, da se v kruhu brez in z dodatkom KPZ večina spojin z antioksidativnim delovanjem nahaja v vezani obliki ne glede na uporabljeno metodo. Večji delež dodanih KPZ ni pomenil nujno tudi večje vsebnosti AO v končnem izdelku, vendar pa se je uporaba KPZ v vseh primerih izkazala za upravičeno. Predlagamo 15 % dodatek KPZ, ki je reaktivnost vezanih fenolnih spojin (FS) v kruhu izboljšal za 22 % v testu FC, 26 % v testu DPPH in 36 % v testu ABTS, reaktivnost ekstraktibilnih FS pa za 131 % v testu FC, 457 % v testu DPPH in 186 % v testu ABTS v primerjavi s kontrolo brez KPZ. Razvoj funkcionalnih izdelkov kot je kruh z dodatkom KPZ je smotrn zlasti za ljudi, ki zaužijejo premalo polnozrnatih žit in AO. Spelt (Triticum spelta) is a type of grain that has recently been rediscovered. Whole spelt grains are important source of bioactive compounds, which may reduce oxidative stress in human body. In our research the impact of added sprouted spelt grains (KPZ) on the content of antioxidants (AO) in bread was studied. Samples were analysed spectrophotometrically using the Folin-Ciocalteu (FC) reagent, the DPPH radical and the ABTS radical. The results were expressed as the equivalent of chlorogenic acid and it was determined that in bread without and with the addition of KPZ, most of the compounds with antioxidative activity are in bound form, regardless of the method used. The higher addition of sprouted spelt grains did not necessarily result into higher AO value of the final product, however, the use of KPZ was found to be justified in all cases. The addition of 15 % of KPZ would be recommended, which improved the reactivity of bound phenolic compounds (FS) in bread for 22 % in the FC test, 26 % in the DPPH test and 36 % in the ABTS test, and the reactivity of the extractable FS for 131 % in the FC test, 457 % in the DPPH test and 186 % in the ABTS test compared to the control without KPZ. The development of functional products such as bread with the addition of KPZ is especially important for people consuming too little whole grain cereals and AO.

V okviru diplomskega dela smo želeli ugotoviti, kako različen čas kaljenja semen industrijske konoplje (Cannabis sativa L.) vpliva na vsebnost skupnih fenolnih spojin. Odstotek suhe snovi smo v izhodnem materialu za pripravo ekstraktov določili s sušenjem homogeniziranih delno posušenih in razmaščenih semen do konstantne mase. Fenolne spojine smo iz nekaljenih semen in tistih, kaljenih 24, 48, 72 in 96 ur, pridobili s pomočjo metanola (99,8 %). Za ovrednotenje vsebnosti skupnih fenolnih spojin v vzorcih smo uporabili Folin-Ciocaltevo metodo, rezultate pa podali kot ekvivalent klorogenske kisline (KK) v suhi snovi (SS). Raziskava je pokazala zanemarljive razlike v vsebnosti SS med delno posušenimi razmaščenimi semeni, ki so kalili različno dolgo. Ponovljivost ekstrakcije je bila 99,9 %. Vsebnost fenolnih spojin se v semenih konoplje prvih 48 ur kaljenja ni spreminjala, ob naslednjem vzorčenju (72 ur) pa smo zabeležili močan prirast. V naslednjih 24 urah je bil vpliv časa kaljenja še vedno pozitiven, vendar manjši. Po 96 urah kaljenja smo tako določili najvišjo vrednost (4,53 mg KK/g SS), kar je pomenilo 1,7-krat večjo vsebnost skupnih fenolnih spojin kot v nekaljenih semenih. Uživanje kaljenih semen industrijske konoplje predstavlja nove možnosti pri razvoju funkcionalnih živil. In the course of the diploma thesis, we wanted to investigate how different time of germination of industrial cannabis seeds (Cannabis sativa L.) affects the content of total phenolic compounds. The percentage of the dry matter in the starting material for the preparation of extracts was determined by drying homogenized partially dried and defatted seeds to a constant weight. Phenolic compounds were extracted with methanol (99.8 %) from non-germinated seeds and from those, germinated for 24, 48, 72 and 96 hours. Folin-Ciocalt's method was used to evaluate the total phenolic content in the samples, and results were given as the equivalent of chlorogenic acid (KK) in the dry matter (SS). The study showed negligible differences in the content of SS between the partially dried deffated seeds, which germinated for different periods of time. Repeatability of the extraction of the experiment was 99.9 %. Content of phenolic compounds in cannabis seeds did not change during the first 48 hours of germination, however on the next sampling (72 hours) there was a strong increase. In the next 24 hours, the effect of germination time was still positive, but lower. After 96 hours of germination the highest value was determined (4.53 mg KK/g SS), which meant 1.7-fold higher content of phenolic compounds compared to non-germinated seeds. The consumption of germinated seeds of industrial cannabis offers new opportunities for the development of functional foods.

V okviru magistrske naloge smo preučevali vpliv načina osvetljevanja na antioksidativni potencial (AOP) kalčka in preostalega dela kaljenega pšeničnega zrna. Kaljenje je potekalo 4 dni pri 20 °C pod LED lučmi (470 in 520 nm) oz. v temi (kontrola). Po 48 in 96 urah smo kalček ločili od preostalega zrna in pripravili metanolne ekstrakte, preostanek po ekstrakciji pa hidrolizirali z NaOH. S Folin Ciocalteu metodo smo kalčku in preostalemu delu zrna določili vsebnost ekstraktibilnih in vezanih fenolnih spojin, z metodama DPPH in ABTS pa njihov AOP. Intenzivnejše spremembe so potekale v kalčku kot v preostalem zrnu. Uporaba modrih in zelenih LED je vodila k manjši vsebnosti ekstraktibilnih fenolnih spojin in nižjemu AOP ekstraktibilnih antioksidantov tako v zrnih kot kalčkih v primerjavi s temo, medtem ko način osvetljevanja na vsebnost vezanih fenolnih spojin ni imel vpliva. AOP vezanih antioksidantov v zrnih, določen z ABTS metodo, je bil le po 48 urah kaljenja pod LED nižji kot v temi, sicer pa način osvetljevanja zrn in kalčkov ni vplival na AOP ne glede na metodo določanja. Čas kaljenja je statistično značilno vplival na vsebnost ekstraktibilnih fenolnih spojin v zrnih in kalčkih ter na njihov AOP, na vsebnost vezanih fenolnih spojin pa samo v kalčkih, ki so rastli v temi. Z metodo DPPH smo vsem vzorcem določili nižji AOP kot z metodo ABTS. We studied the effect of type of light on antioxidant potential (AOP) of sprouts and the rest of the germinated wheat grains. Wheat grains were germinated for 4 days at 20 °C where LED lights (470 in 520 nm) presented source of light. Germination in darkness presented control. We took samples after 48 and 96 hours of germination and separated sprouts from the grains and than prepared methanolic extracts. The bound phenolic compounds were released from insoluble residues after hydrolysis with NaOH. Content of extractable and bound phenolic compounds was determined with Folin Ciocalteau method, AOP with DPPH and ABTS methods. More intensive changes were observed in sprouts than in the rest of the grains. Use of blue and green LED contributed to the lower extractable phenolic content and their AOP in grains and sprouts compared to control. Type of LED light did not influence the bound phenolic content. AOP of bound phenolics (ABTS method) was lower after 48 hours of germination under LED light than in control. Otherwise type of light did not effect on AOP of grains and sprouts regardless of type of method. Time of germination significantly effected the content of extractable phenolic compounds in grains and sprouts and their AOP regardless of type of light. Furthermore, time of germination effected on bound phenolic compounds only in sprouts which were grown in dark. For all samples higher AOP was determined with ABTS in comparison to DPPH method.

Semena imajo pomembno vlogo v prehrani ljudi, nedavne študije pa so pokazale, da lahko kaljenje še izboljša njihovo hranilno vrednost. V diplomskem delu smo preiskovali antioksidativno učinkovitost industrijske konoplje (Cannabis sativa L.), uporabili smo izvlečke razmaščenih nekaljenih semen in kaljenih 24, 48, 72 ter 96 ur. Antioksidativno učinkovitost izvlečkov smo spremljali z metodo določitve sposobnosti lovljenja DPPH• radikala in metodo razbarvanja β-karotena. Osrednje rezultate smo podali kot delež preostalega DPPH• po 30 min oz. jih izrazili kot učinkovitost izvlečkov zoper razbarvanje β-karotena po 120 min. Ugotovili smo, da se sposobnost lovljenja DPPH• radikalov tekom kaljenja spreminja, pri čemer po 48 urah kaljenja zaznamo celo nižjo učinkovitost izvlečkov v primerjavi z nekaljenimi semeni (27 %). Najvišjo sposobnost lovljenja prostih radikalov imajo semena kaljena 96 ur (36 %). Pri metodi razbarvanja β-karotena rezultati nekoliko odstopajo sprva sicer opazimo upad antioksidativne učinkovitosti. Za maksimalno (61 %) učinkovitost izvlečkov pa je zadostovalo že 72 ur kaljenja. Slaba korelacija obeh metod je potrdila razlike v antioksidativni učinkovitosti izvlečkov v homogenem in heterogenem okolju. Izkazalo se je, da se hitrost reakcije v obeh primerih s časom inkubacije upočasni, medtem ko se posamezni vzorci bistveno ne razlikujejo v kinetiki delovanja. Seeds have a very important role in human nutrition and recent studies have shown that germination of seeds improved their nutritional value. In graduate thesis we investigated antioxidant efficacy of industrial hemp (Cannabis sativa L.). The extracts of defatted non-germinated and germinated seeds for 24, 48, 72, 96 h were used. Antioxidant efficacy of extracts was measured with DPPH• radical scavenging method and β-carotene bleaching assay. The results were expressed as percentage of remaining DPPH• radical after 30 min and as extract efficiency against β-carotene bleaching after 120 min. From the DPPH• assay we can conclude that antioxidant efficacy is changing during germination. After 48 h lower extract efficacy is determined when compared to non-germinated seeds (27 %). The highest DPPH• scavenging activity express 96 h germinated seeds (36 %). These results don’t coincide with β-carotene bleaching test a decrease of antioxidant efficacy for extracts of seeds germinated for 24 h is noticed, meanwhile the highest extract efficacy (61 %) after 72 h of germination is determined. The weak correlation of both methods confirms differences in the antioxidative efficacy of extracts in a homogeneous and heterogeneous environment. It has been shown that the reaction rate decreases with time of incubation in both cases, while there is no differences in kinetics between individual samples.

Številne študije na različnih rastlinah dokazujejo povečanje količine fenolnih snovi in antioksidativnega potenciala (AOP) med kaljenjem pod svetlobo različnih valovnih dolžin, zato je bil namen naše magistrske naloge preveriti, če enak trend velja tudi za kaljeno piro. Zrna smo v standardnih pogojih (20 °C, 99 % vlažnost) 96 ur kalili pod LED svetlobo in v temi. Po 48 in 96 urah smo kalčke ločili od zrn in s postopki ekstrakcije, hidrolize, ekstrakcije na trdni fazi in spektrofotometričnimi metodami določili vsebnost ekstraktibilnih in vezanih antioksidativnih spojin v neprečiščenih in prečiščenih vzorcih zrn in kalčkov. Ugotovili smo, da v kalčku prvih 96 ur kaljenja prevladujejo ekstraktibilni antioksidanti, v preostalem kaljenem zrnu pa vezani antioksidanti. V zrnu se je med kaljenjem povečala količina ekstraktibilnih fenolnih spojin, v kalčku pa vezanih. Spremembe so bile kvantitativno večje v kalčku v primerjavi z zrnom, kar potrjuje nastanek novih spojin. Rezultati med FC in ABTS metodo so primerljivi, vrednosti izmerjene z DPPH metodo pa so precej nižje. To pripisujemo slabši reaktivnosti prevladujoče ferulne kisline z DPPH radikali. Do sprememb v vsebnosti spojin z antioksidativnim delovanjem torej prihaja, vendar kaljenje pod izbranimi valovnimi dolžinami (470 in 520 nm) neznačilno vpliva tako na količino kot AOP ekstraktibilnih in vezanih fenolnih spojin kaljene pire. Numerous studies in various plants prove the increase in the amount of phenolic compounds and antioxidant potential (AOP) during the germination under the light of different wavelengths. Therefore, the purpose of our master’s thesis was to verify whether the same trend applies to spelt. Under standard conditions (20 °C, 99 % humidity), grains were concurrently germinated under the LED light and in the dark for 96 hours. After 48 and 96 hours, the germs were separated from the grains and then through the procedures of extraction, hydrolysis, and solid phase extraction and through spectrophotometric methods the contents of free and bound antioxidant compounds in grain and germ samples were determined. The results showed that after 96 hours of germination free antioxidants were predominant in the germ, whereas bound antioxidants were predominant in the remaining grain. During germination, the amount of free phenolic compounds increased in the grain, while that of bounded phenolic compounds increased in the germ. The changes were quantitatively more considerable in germ compared to grain, which attests to the emergence of new compounds. The results of the FC and of the ABTS method are comparable, whereas the values measured using the DPPH method are significantly lower due to the lower reactivity of the prevalent ferulic acid with DPPH radicals. Undeniably, there are changes in the amount of antioxidant compounds during the germination however, germinating under specific wavelengths (470 and 520 nm) has no significant effect on the quantity of free and bound phenolic compounds and their AOP.

V diplomskem delu smo želeli proučiti vpliv pogojev slajenja na antioksidativno učinkovitost (AU) rženega (Secale cereale L.) slada. Kaljena zrna smo vzorčili vsakih 24 ur in jih sušili pri temperaturi 60 ºC oz. 100 ºC. Sposobnost lovljenja prostih radikalov smo določili z metodo DPPH• in rezultate podali kot ekvivalent troloksa. Rezultati so pokazali, da namakanje zrn negativno vpliva na količino prisotnih antioksidantov. AU slada je pri etanolnih ekstraktih naraščala ves čas poskusa (96 ur), medtem ko smo pri metanolnih ekstraktih zadnji dan kaljenja zabeležili manjši upad, vendar samo, če smo slad sušili pri 100 ºC. Ugotovili smo, da je učinkovitost antioksidantov v sladu, sušenem pri 100 °C boljša kot v sladu, sušenem pri 60 °C, ter da je AU spojin, ekstrahiranih z metanolom, višja od tistih, ki so ekstrahirane z etanolom, neodvisno od časa kaljenja in pogojev sušenja. Najvišjo AU smo določili v metanolnem ekstraktu slada, ki je bil podvržen 72-urni biološki aktivaciji in temperaturi sušenja 100 °C (0,89 mg troloks/g suhi vzorec), ko je prirast AU znašala 106 % v primerjavi z AU neslajene rži. Zaključimo lahko, da daljši čas kaljenja poveča AU rženega slada ter da temperatura sušenja in pogoji ekstrakcije znatno vplivajo na AU ekstraktov. The purpose of the thesis was to examine the influence of malting on the antioxidant efficiency (AE) of rye (Secale cereale L.) malt. Germinated grains were sampled every 24 hours and kilned at a temperature of 60 ºC and 100 ºC. The free radical scavenging activity was determined by DPPH• method and the results were expressed as trolox equivalent. The results showed that steeping of the grain has a negative effect on the amount of antioxidants present. AE of ethanolic malt extracts increased throughout the experiment (96 hours), while in the case of methanolic extracts a smaller decrease on the last day of germination was observed, but only if the malt was kilned at 100 °C. The efficiency of antioxidants in malt dried at 100 °C was found to be better than those from malt dried at 60 °C. Furthermore AE of compounds extracted with methanol was found to be higher than those extracted with ethanol, regardless to the germination time and kilning conditions. The highest AE was observed for the methanolic extract of the malt that was subjected to 72-hour biological activation and kilning temperature of 100 °C (0.89 mg Trolox/g dw). When AE was increased for the 106 % compared to the AE of unmalted rye. It can be concluded that longer germination time increases the AE of rye malt and that the kilning temperature and extraction conditions significantly affect the AE of the extracts.

V sklopu diplomskega dela smo želeli preučiti vpliv različne priprave rženega (Secale cereale L.) slada na vsebnost skupnih fenolnih spojin. Namakanju zrn je sledilo večdnevno kaljenje in sušenje pri dveh različnih temperaturah, 60 in 100 °C. Vzorčenje je potekalo vsakih 24 ur, ko smo iz rženega slada s solventno ekstrakcijo pripravili ekstrakte fenolnih spojin. Uporabili smo topili različne polarnosti, metanol in etanol. Celokupno koncentracijo fenolnih spojin v ekstraktih smo spektrofotometrično določili s pomočjo Folin-Ciocalteujeve metode in jo izrazili kot ekvivalent ferulne kisline (FK). Ugotovili smo, da čas kaljenja pozitivno vpliva na vsebnost fenolnih spojin. 96 ur po biološki aktivaciji zrn je bila vsebnost fenolnih spojin najvišja. Izkazalo se je, da je vsebnost fenolnih spojin v rženem sladu sušenem pri 100 °C višja kot v sladu sušenem pri 60 °C. Opazili smo tudi, da je vsebnost fenolnih spojin, ekstrahiranih z metanolom, višja od tistih, ki so ekstrahirane z etanolom ne glede na čas kaljenja ali temperaturo sušenja. Vsebnost fenolov je bila tako najvišja v metanolnem ekstraktu, kjer so bila ržena zrna vzorčena po 96 urah in sušena pri 100 °C (27,4 ± 0,1 mg FK/g suhe snovi) in je bila kar 5,5-krat večja v primerjavi z vsebnostjo v etanolnem ekstraktu pripravljenem pri istih pogojih. As part of the thesis, the influence of varying preparation conditions of rye malt (Secale cereale L.) on the phenolic compounds content was studied. After the grains were soaked, they were germinated for several days and dried at two different temperatures, 60 °C and 100 °C. The sampling was carried out every 24 hours, by preparing the extracts of phenolic compounds from rye malt with solvent extraction. Methanol and ethanol, two varying polar solvents, were used for the extraction. With the aid of the Folin-Ciocalteu method, the concentration of phenolic compounds in the extracts was determined spectrophotometrically and expressed as ferulic acid equivalents (FA). The phenolic compounds content increased with the time of germination of the rye, meaning that the longer the grain was germinated, the higher was the content. The content was the highest after 96 hours after the biological activation of the grains. Furthermore, the phenolic compounds content of the malt dried at 100 °C was higher than of that dried at 60 °C. Another observation was that the content of the phenolic compounds extracted with methanol was higher than of those extracted with the use of ethanol, regardless of the time of germination and the temperature of drying. The phenolic compounds content was the highest in the methanol extract, wherein the rye grains were germinated for 96 hours at 100 °C (27.4 ± 0.1 mg FA/g dry weight) and was 5.5-fold higher than the value of the ethanol extract prepared under the same conditions.

Zaradi številnih pozitivnih učinkov na zmanjševanje pojava kroničnih bolezni, se antioksidantivnemu potencialu (AOP) živil daje vedno večji pomen. V okviru diplomskega dela smo želeli preučiti vpliv procesa kaljenja na vsebnost fenolnih spojin in AOP rženih (Secale cereale) zrn. Za pripravo ekstraktov fenolnih spojin smo uporabili metanol. Tako vsebnost fenolih spojin kot AOP smo določali spektrofotometrično, in sicer z uporabo Folin-Ciocalteu-jevega reagenta in DPPH• radikala. Vsebnost fenolnih spojin smo izrazili kot ekvivalent ferulne kisline (FK) na g suhe snovi (mg FK/g SS), AOP pa kot ekvivalent troloksa na g suhe snovi (mg troloks/g SS). Rezultati so pokazali, da v analiziranih ekstraktih s časom kaljenja naraščata tako koncentracija fenolnih spojin kot AOP, prvi opaznejši dvig smo opazili 72 ur po začetku namakanja. Ugotovili smo močno pozitivno korelacijo med vsebnostjo fenolnih spojin in AOP kaljene rži. Maksimalno vsebnost fenolnih spojin in antioksidantov v rženih zrnih smo določili po 96 urah biološke aktivacije, ko je vsebnost fenolnih spojin znašala (3,5 ± 0,2) mg FK/g SS, vrednost AOP pa (1,41 ± 0,03) mg troloks/ g SS. Kaljenje zrn je tako vodilo v 3,5-kratno povečanje količine skupnih fenolnih spojin in 3,7-kratno izboljšanje AOP v zgolj štirih dneh. Zaradi izkazanih lastnosti je takšna semena moč uporabiti pri proizvodnji funkcionalnih živil. Antioxidant potential (AOP) of foods is becoming increasingly important due to its many positive effects on reduced incidence of chronic disease. Within the diploma thesis we wanted to study the influence of the germination on the phenolic compounds content and the AOP of rye ( Secale cereale) seeds. Methanol was used to prepare extracts of phenolic compounds. The content of phenolic compounds and the antioxidant potential were determined spectrophotometrically using the Folin-Ciocalteu reagent and the DPPH• radical. The content of phenolic compounds was expressed as ferulic acid equivalent (FK) per g of dry weight (mg FK/g DW), meawhile AOP was expressed as the trolox equivalent per g of dry weight (mg trollox/g DW). The results showed that the concentration of phenolic compounds and AOP increased with the germination time the first noticeable increase was observed 72 hours after steeping of the seeds. We have established a strong positive correlation between the content of phenolic compounds and AOP of germinated rye. The maximum content of phenolic compounds and antioxidants in rye grains was determined after 96 hours of biological activation when content of phenolic compounds amounted to (3,5 ± 0,2) mg FK/g DW, and the AOP value reached (1,41 ± 0,03) mg of trolox/g DW. The amounts of total phenolic compounds increased 3,5-fold, while germination of the rye seeds resulted in a 3,7-fold increase in AOP in only four days. Because of the properties shown, such seeds can be used in the production of functional foods.