Effect of antioxidants on stabilization of mixture hazelnut and linseed oil

Postupkom hladnog prešanja iz sjemenki lana i jezgre lješnjaka proizvodi se jestivo ulje visoke nutritivne vrijednosti. U ovom radu istraživan je utjecaj dodatka antioksidanasa (prirodni, sintetski) i sinergista na oksidacijsku stabilnost mješavine lješnjakovog i lanenog ulja (50:50). Od prirodnih antioksidanasa korišteni su ekstrakt kadulje, ekstrakt ružmarina, ekstrakt nara, mješavina tokoferola, eterično ulje konopljike, lavande, slatkog pelina, divlje mrkve, smilja, a od sintetskih propil galat. Određivanje oksidacijske stabilnosti mješavine ulja te utjecaj dodatka antioksidansa i sinergista provedeno je testom ubrzane oksidacije ulja Schaal Oven testom. Rezultat oksidacije mješavine ulja izražen je peroksidnim brojem. Primjenom standardnih metoda u ulju su određeni osnovni parametri kvalitete (peroksidni broj, slobodne masne kiseline, voda, netopljive nečistoće). Rezultati ispitivanja pokazuju da ekstrakt ružmarina (sa i bez limunske kiseline) efikasnije štiti mješavinu ulja od oksidacijskog kvarenja u odnosu na druge ispitivane antioksidanse. Eterično ulje slatkog pelina ne pokazuje utjecaj na stabilizaciju ove mješavine ulja.The process of cold pressing linseed and hazelnut kernels produces edible oil of high nutritional value. In this paper, the influence of addition antioxidants (natural, synthetic) and synergists on the oxidative stability of mixture hazelnut and linseed oil (50:50) was investigated. The testing was carried out using the natural antioxidants sage extract, rosemary extract, pomegranate extract, tocopherol mixture, essential oil of hemp, lavender, sweet wormwood, wild carrot, immortelle, and synthetic propyl gallate. The oxidative stability of the oil mixture and the effect of addition of antioxidant and synergists were determined by the accelerated oil oxidation test, the Schaal Oven test. The result of the oil mixture oxidation was expressed by the peroxide value. The basic quality parameters (peroxide value, free fatty acids, water, insoluble impurities) were determined by applying the standard methods to oil. The results of testing indicated that rosemary extract (with and without citric acid) protect the oil mixture from oxidative spoilage more effectively than compared to other tested antioxidants. The essential oil of sweet wormwood shows no effect on the stabilization of this oil mixture

PRODUCTION AND STABILIZATION OF PEANUT OIL

The colour of peanut oil is pale-yellow, it has a neutral scent and it is rich in oleic and linoleic acid. The aim of this study was to investigate the effect of peanut kernel conditioning (25 °C, 35 °C, 45 °C, 55 °C), the addition of sunflower shells (3%, 6%, 9%), and the usage of oil during pressing. Peanut pressing is performed with a continuous press. Following the pressing process, a decision is made on the volume and the temperature of crude oil, as well as on pressing time. The additional steps include the natural precipitation of crude oil and the vacuum filtration of crude oil to obtain cold pressed oil. Some of the basic parameters for oil quality that are determined using standard methods are: peroxide number, free fatty acids, the proportion of insoluble impurities, and moisture content. Additionally, the results of the addition of natural and synthetic antioxidants on the oxidation stability of cold pressed peanut oil were examined. Finally, the results of the research show that conditioning and the addition of sunflower shells affect oil recovery during the pressing process. Conditioning peanuts at higher temperatures and the addition of a larger proportion of sunflower hulls resulted in greater amounts of produced oil. The natural antioxidant rosemary extract and synthetic propyl gallate achieve greater protection from oxidative degradation for the oil

PRODUCTION AND STABILIZATION OF PEANUT OIL

The colour of peanut oil is pale-yellow, it has a neutral scent and it is rich in oleic and linoleic acid. The aim of this study was to investigate the effect of peanut kernel conditioning (25 °C, 35 °C, 45 °C, 55 °C), the addition of sunflower shells (3%, 6%, 9%), and the usage of oil during pressing. Peanut pressing is performed with a continuous press. Following the pressing process, a decision is made on the volume and the temperature of crude oil, as well as on pressing time. The additional steps include the natural precipitation of crude oil and the vacuum filtration of crude oil to obtain cold pressed oil. Some of the basic parameters for oil quality that are determined using standard methods are: peroxide number, free fatty acids, the proportion of insoluble impurities, and moisture content. Additionally, the results of the addition of natural and synthetic antioxidants on the oxidation stability of cold pressed peanut oil were examined. Finally, the results of the research show that conditioning and the addition of sunflower shells affect oil recovery during the pressing process. Conditioning peanuts at higher temperatures and the addition of a larger proportion of sunflower hulls resulted in greater amounts of produced oil. The natural antioxidant rosemary extract and synthetic propyl gallate achieve greater protection from oxidative degradation for the oil

Influence of black cumin seed pressing on the production and quality of cold pressed oil

U ovom radu istraživan je utjecaj procesnih parametara prešanja sjemenki crnog kima na prinos hladno prešanog ulja te njegovu kvalitetu. Prešanje sjemenki crnog kima provedeno je na laboratorijskoj pužnoj preši za proizvodnju hladno prešanih biljnih ulja. Prešanjem su dobivena tri proizvoda: sirovo ulje, uljni talog i pogača. Prilikom prešanja mijenjani su procesni parametri: frekvencija elektromotora, temperatura grijača glave preše i nastavak za izlaz pogače. Nakon prešanja provedena je sedimentacija (prirodno taloženje) proizvedenog sirovog ulja te vakuum filtracija kako bi se uklonile krute čestice. Primjenom standardnih metoda određeni su parametri kvalitete hladno prešanog ulja crnog kima: slobodne masne kiseline, peroksidni broj, udio netopljivih nečistoća i udio vlage. Primjenom plinske kromatografije određen je sastav masnih kiselina u ulju. Dobiveni rezultati istraživanja pokazuju da je prešanje crnog kima primjenom nastavka za izlaz pogače veličine 5 mm, temperature grijača glave preše 110 °C i frekvencije elektromotora 20 Hz proizvedena najveća količina sirovog i hladno prešanog ulja crnog kima. U sastavu masnih kiselina ulja crnog kima dominiraju linolna i oleinska masna kiselina.This thesis, discusses the influence and quality of process parameters of pressing black cumin seeds on the yield of cold pressed oil. Pressing black cumin seeds was carried out on laboratory screw press for the production of cold pressed vegetable oils. Three products were obtained by pressing: crude oil, sludge oil and cake. During pressing, the process parameters were changed: the frequency of the electric motor, the temperature of the heater of the press head and the extension for the outlet of the cake. After pressing, sedimentation (natural precipitation) of the produced crude oil and vacuum filtration were performed to remove solid particles. Using standard methods, the quality of parameters of cold-pressed black cumin oil were determined: free fatty acids, peroxide value, insoluble impurities content and moisture content. The composition of fatty acids in oil was determined using gas chromatography. The obtained research results show that the pressing black cumin using a 5 mm cake outlet extension, a press heater head temperature of 110 ° C and an electric motor frequency of 20 Hz produced the largest amount of crude and cold-pressed black cumin oil. In the composition of fatty acids black cumin oil is dominated by linoleic and oleic fatty acids

The Influence of Microwave Heating and Addition of Antioxidants on the Shelf life of Ekstra Virgin Olive Oil variety Oblica

Djevičansko maslinovo ulje ima veliku otpornost prema oksidacijskom kvarenju, zbog sastava triacilglicerola s niskim udjelom polinezasićenih masnih kiselina i skupine fenolnih antioksidansa sastavljenih uglavnom od polifenola i tokoferola. U ovom radu istraživan je utjecaj mikrovalnog zagrijavanja na oksidacijsku stabilnost ekstra djevičanskog maslinovog ulja, sa i bez dodatka antioksidansa i sinergista. Od prirodnih antioksidansa korišteni su ekstrakt ružmarina i ekstrakt zelenog čaja te sinergist limunska kiselina. Uzorci ulja sa i bez dodatka antioksidansa i sinergista zagrijavani su u mikrovalnoj pećnici kod konstante snage 300 W u različitom vremenskom periodu (5, 10, 15 i 20 minuta). Uzorci su također zagrijavani i kod različite snage uređaja (180, 300, 450W) u konstantnom vremenskom periodu 5 minuta. Rezultat testa ubrzane oksidacije ekstra djevičanskog maslinovog ulja izražen je peroksidnim brojem. Mikrovalnim zagrijavanjem uzoraka tijekom duljeg vremena zagrijavanja dolazi do porasta temperature i vrijednosti peroksidnog broja, odnosno dolazi do porasta oksidacijskog kvarenja ulja. Dodatkom antioksidansa i sinergista povećana je stabilnost ekstra djevičanskog maslinovog ulja. Najveća stabilnost ekstra djevičanskog maslinovog ulja postignuta je kombinacijom ekstrakta zelenog čaja i sinergista limunske kiseline.Virgin olive oil has a high resistance to oxidative deterioration due to both a triacylglycerol composition low in polyunsaturated fatty acids and a group of phenolic antioxidants composed mainly of polyphenols and tocopherols. This essay discusses the effect of microwave heating on the oxidative stability of extra virgin olive oil with or without the addition of antioxidants and synergists. Of natural antioxidants are used rosemary extract and green tea extract and citric acid synergist. Oil samples with or without the addition of antioxidants and synergists were heated in a microwave oven at a constant power of 300 W over a different time period (5, 10, 15 and 20 minutes). Samples were also heated at different power levels (180, 300, 450W) in a constant time period of 5 minutes. The result of the accelerated oxidation test of olive oil is expressed by the peroxide number. Microwave heating of the samples during a longer heating time increases the temperature and the value of the peroxide number, which results in an increase in oxidative oil degradation. Addition of antioxidants and synergists increased the stability of olive oil. The highest stability of extra virgin olive oil was achieved by a combination of green tea extract and synergistic citric acid

La influencia de los antioxidantes añadidos sobre la estabilidad oxidativa de la grasa de res

Masti se nalaze u sastavu većine namirnica koje se svakodnevno konzumiraju. Goveđi loj je jedna od najsloženijih masti u prirodi. Loj podliježe oksidacijskom kvarenju tijekom proizvodnje, skladištenja i toplinske obrade. U ovom radu istraživan je utjecaj dodatka prirodnih antioksidanasa (ekstrakt ružmarina tip Oxy’Less CS, tip StabilEnhance, ekstrakt kadulje, alfa tokoferol, mješavina tokoferola) i sintetskih antioksidanasa (PG, BHA) na promjenu oksidacijske stabilnosti goveđeg loja. Oksidacijska stabilnost goveđeg loja, sa i bez dodanog antioksidansa, ispitivana je primjenom testa održivosti na 98 °C. Rezultati testa prikazani su kao vrijednost peroksidnog broja (mmol O2/kg) nakon određenog vremena držanja uzorka pri temperaturi 98 °C. Rezultati istraživanja pokazuju da primijenjeni antioksidansi uspješno stabiliziraju goveđi loj. Od prirodnih antioksidanasa veću antioksidacijsku aktivnost u goveđem loju ima ekstrakt ružmarina tip Oxy’Less CS. Postigao je veću efikasnost zaštite goveđeg loja od oksidacije, u odnosu na druge ispitivane prirodne antioksidanse. Sintetski antioksidansi propil galat i butilhidroksianisol uspješno su povećali stabilnost goveđeg loja, a veće antioksidacijsko djelovanje pokazuje propil galat.Fats are contained in the majority of foods that are consumed daily. Beef tallow is one of the most complex fats found in nature. Tallow is subject to oxidation during the production, storage and heat treatment. This study researched the effect of natural antioxidants (rosemary extract type Oxy’Less CS and type StabilEnhance, sage extract, alpha tocopherol, mixture tocopherol) and synthetic antioxidants (PG, BHA) on the oxidative stability of beef tallow. The oxidative stability of beef tallow, with and without added antioxidant, was evaluated using the sustainability test at 98 oC. The results are expressed as peroxide value (mmol O2/kg) obtained after storing the sample for a certain period of time at the temperature of 98°C. The results showed that applied antioxidants successfully stabilized the beef tallow. Among natural antioxidants, rosemary extract type Oxy\u27Less CS showed a higher antioxidant activity in beef tallow. In comparison with other tested antioxidants, it achieved greater efficiency in protecting the beef tallow from oxidation. Synthetic antioxidants propyl galate and butylhydroxyanisole successfully increased the stability of beef tallow, whereby propyl galate showed a higher antioxidant activity.Fette sind Bestandteil der meisten Lebensmittel, die täglich konsumiert werden. Rindertalg ist eines der komplexesten Fette in der Natur. Talg oxidiert während der Herstellung, Lagerung und Wärmebehandlung. In dieser Arbeit wurde die Wirkung natürlicher Antioxidantien (Rosmarinextrakt vom Typ Oxy’Less CS und Typ StabilEnhance, Salbei-Extrakt, Alpha-Tocopherol, Tocopherol Gemisch) und synthetischer Antioxidantien (PG, BHA) auf die oxidative Stabilität von Rindertalg untersucht. Die oxidative Stabilität von Rindertalg mit und ohne Zusatz von Antioxidationsmitteln wurde unter Verwendung des Nachhaltigkeitstests bei 98°C geprüft. Die Ergebnisse wurden als Peroxidzahlwert (mmol O2/kg) ausgewiesen, nachdem die Probe einen bestimmten Zeitraum bei einer Temperatur von 98°C gehalten wurde. Die Ergebnisse zeigten, dass die eingesetzten Antioxidantien den Rindertalg erfolgreich stabilisieren. Von den natürlichen Antioxidantien weist der Rosmarinextrakt vom Typ Oxy\u27Less CS eine höhere antioxidative Aktivität im Rindertalg auf. Im Vergleich zu anderen getesteten Antioxidantien, konnte er den Rindertalg effizienter vor der Oxidation schützen. Synthetische Antioxidationsmittel Propylgallat und Butylhydroxyanisol konnten die Stabilität von Rindertalg erfolgreich erhöhen, wobei Propylgallat eine höhere antioxidative Aktivität aufweist.I grassi fanno parte della gran parte dei cibi che consumiamo quotidianamente. Il grasso bovino, o sego, è uno dei grassi più complessi in natura. Il sego è soggetto a deterioramento ossidativo durante la produzione, l’immagazzinamento e il trattamento termico. In questo studio è stato esaminato l’impatto dell’aggiunta di antiossidanti naturali (estratto di rosmarino tipo Oxy’Less CS, tipo StabilEnhance, estratto di salvia, alfa tocoferoli, mix di tocoferoli) e di antiossidanti di sintesi (PG, BHA) sulla stabilità ossidativa del sego. La stabilità ossidativa del sego, co o senza l’aggiunta di antiossidante, è stata esaminata mediante l’applicazione del test di sostenibilità a 98 °C. I risultati del test sono stati illustrati come valore del numero di perossido (mmol O2/kg) dopo un certo tempo in cui il campione è stato tenuto alla temperatura di 98 °C. I risultati dello studio mostrano che l’uso di antiossidanti stabilizza efficacemente il grasso bovino. Tra quelli naturali, la maggior attività antiossidante sul grasso bovino è stata evidenziata dall’estratto di rosmarino tipo Oxy’Less CS che s’è dimostrato più efficace nella protezione del sego dall’ossidazione rispetto agli altri antiossidanti naturali testati. Gli antiossidanti di sintesi, come il propil-gallato e il butilidrossianisolo, hanno efficacemente aumentato la stabilità ossidativa del sego, con una prevalenza in questo senso del propil-gallato.Las grasas forman parte de la mayoría de los alimentos consumidos diariamente. La grasa de res es una de las grasas más complejas en la naturaleza. La grasa está sujeta al deterioro oxidativo durante la producción, almacenamiento y el tratamiento térmico. En este trabajo fue investigada la influencia de la añadidura de los antioxidantes naturales (el extracto de romero tipo Oxy’Less CS, el tipo StabilEnhance, el extracto de salvia, el alfa-tocoferol, la mezcla de tocoferol) y de los antioxidantes sintéticos (PG, BHA) sobre el cambio de la estabilidad oxidativa de la grasa de res. La estabilidad oxidativa de la grasa de res, con y sin antioxidantes, fue analizada por la prueba de sostenibilidad a los 98 °C. Los resultados de la prueba fueron expresados por el número de peróxido (mmol O2/kg) después de mantener las muestras a los 98 °C por cierto período de tiempo. Los resultados de la investigación muestran que los antioxidantes aplicados estabilizan satisfactoriamente la grasa de res. Entre los antioxidantes naturales, la mayor actividad antioxidante en la grasa de res tiene el extracto de romero tipo Oxy’Less CS. Alcanzó mayor eficiencia de protección de la grasa de res de la oxidación, en comparación con otros antioxidantes naturales probados. Los antioxidantes sintéticos el galato de propilo y el hidroxibutilanisol aumentaron la estabilidad de la grasa de res y el galato de propilo mostró mayor actividad antioxidante

OXIDATIVE STRESS UNDER INTENSE PHYSICAL EXERTION IN HUMANS AND ANIMALS

Poremećaj ravnoteže u organizmu između proizvodnje reaktivnih kisikovih radikala (ROS) i antioksidansa nazivamo oksidacijskim stresom. Do pomaka ravnoteže dolazi ukoliko je smanjena antioksidacijska obrana organizma ili ako je povećano stvaranje slobodnih radikala. Antioksidansi su sve one tvari koje u maloj količini u kratkome vremenu neutraliziraju djelovanje slobodnih radikala i drugih oksidansa. Oni nastaju u stanici ili se u organizam unose hranom ili u obliku dodataka. Antioksidansi onemogućuju stvaranje slobodnih radikala u organizmu, uništavaju stvorene slobodne radikale ili popravljaju oštećenja u stanici nastala djelovanjem slobodnih radikala.U radu su prikazani biomarkeri oksidacijskog stresa u ljudi i životinja, prema podjeli na enzimske, neenzimske, te ostale biomarkere s naglaskom na biomarkere umora perifernih mišića. Biomarkeri umora perifernih mišića u ljudi i životinja su markeri staničnog mišićnog oštećenja i pokazatelji mišićnog stresa, a koriste se za uvid u mehanizme iscrpljenosti tijekom vježbanja kako bi se otkrio povećani umor ili se otkrili manjkavi metabolički putevi. Utvrđivanje oksidacijskog stresa važno je zbog mogućnosti pravovremenog uključivanja antioksidacijskih tvari koji povećavaju antioksidacijski kapacitet ljudskog i životinjskog organizma.Oxidative stress indicates an imbalance in the body between pro-oxidant and antioxidant in favor of a pro-oxidant. To shift the balance may occur if the reduced antioxidant defense of the body or if the increased production of free radicals. Antioxidants are those substances that in a small amount in a short time can neutralize free radicals and other oxidants. They are produced in the cell or organism in food intake or in the form of dietary antioxidants in food or liquid to drink. Antioxidants prevent the formation of free radicals in the body, destroying free radicals created or repair damage in cells caused the action of free radicals. Paper showed biomarkers of oxidative stress in humans and animals, divided to enzymatic, non-enzymatic and other. Biomarkers of peripheral muscle fatigue in humans and animals are markers of cellular muscle damage and muscle stress indicators, and are used for insight into the mechanisms of fatigue during exercise to detect increased fatigue or found deficient metabolic pathways. The determination of oxidative stress is important because of the possibility of timely inclusion of antioxidant substances that increase the antioxidant capacity of human and animal organism

BREEDING MAIZE FOR RESISTANCE TO NORTHERN LEAF BLIGHT (Exserohilum turcicum Pass.)

Siva pjegavost lista kukuruza koju uzrokuje gljiva Exserohilum turcicum (Pass.) najvažnija je lisna bolest kukuruza u humidnom području. Prvi hibridi kukuruza u SAD-u bili su osjetljivi prema ovoj bolesti. Zbog toga je započet program oplemenjivanja na otpornost koji se pokazao vrlo uspješnim. Rabljena je poligenetska i monogenetska otpornost. Međutim nakon 15 godina široke i neprekidne uporabe monogenetske otpornosti u SAD-u dolazi do pojave novog patotipa Exserohilum turcicum, rase 2, koja je kasnije nazvana rasa 1 budući da protiv nje gen Ht 1 nije djelotvoran. Nova rasa se brzo raširila u Americi, a kasnije i u Hrvatskoj. U svrhu proučavanja otpornosti kukuruza prema rasi 1 Exserohilum turcicum posijan je 2008. godine pokus sa 75 linija različitog porijekla. Linije iz heterotične grupe BSSS su bile osjetljive prema rasi 1 Exserohilum turcicum s prosječnom ocjenom 3,0, dok su linije iz heterotične grupe Lancaster otporne s prosječnom ocjenom 2,0. U drugom pokusu 2012. godine ispitana je otpornost 25 linija kukuruza prema rasi 0 i rasi 1 s ciljem da se utvrdi koje su linije otporne prema obje rase Exserohilum turcicum. Linije Pa875, Bc210K, H102, Bc1411, Pa887P, H111 i H95 otporne su p rema obje rasi 0 i r asi 1 Exserohilum turcicum. Monogenetska otpornost prema rasi 1 unesena je u 4 linije kukuruza (A632, Bc31002, Bc703-19 i Bc14).Northern leaf blight, caused by the fungus Exserohilum turcicum (Pass.) is the most important leaf disease of maize in humid environments. The first maize hybrids in the United States were susceptible to this disease. Therefore, breeding program for resistance was initiated and proved to be very successful. Polygenic and monogenic resistance were used. However, after 15 years of continuous and extensive use of monogenic resistance in the United States occurrence of a new pathotype of E.turcicum. race 2 was reported, which was later named race 1, because Ht 1 gene was not effective against it. New race quickly spread throughout the United States, and later in Croatia. To study maize resistance to race 1 of E. turcicum a trial was planted with 75 lines of different origin in 2008. The lines from the BSSS heterotic group were susceptible to race 1 of Exserohilum turcicum with average rating 3,0, while the lines from the Lancaster heterotic group were resistant with average rating 2,0. In the second experiment in 2012., 25 maize lines were tsted for resistance to race 0 and race 1 to detect lines resistant to both races of Exserohilum turcicum. Lines Pa875, Bc210K, H102, Bc1411, Pa887P, H111 and H95 appear to be resistant to both race 0 and race 1 of Exserohilum turcicum. Monogenic otpornost resistance to race 1 was incorporated into four maize lines (A632, Bc31002, Bc703-19 i Bc14)

BREEDING MAIZE FOR RESISTANCE TO NORTHERN LEAF BLIGHT (Exserohilum turcicum Pass.)

Siva pjegavost lista kukuruza koju uzrokuje gljiva Exserohilum turcicum (Pass.) najvažnija je lisna bolest kukuruza u humidnom području. Prvi hibridi kukuruza u SAD-u bili su osjetljivi prema ovoj bolesti. Zbog toga je započet program oplemenjivanja na otpornost koji se pokazao vrlo uspješnim. Rabljena je poligenetska i monogenetska otpornost. Međutim nakon 15 godina široke i neprekidne uporabe monogenetske otpornosti u SAD-u dolazi do pojave novog patotipa Exserohilum turcicum, rase 2, koja je kasnije nazvana rasa 1 budući da protiv nje gen Ht 1 nije djelotvoran. Nova rasa se brzo raširila u Americi, a kasnije i u Hrvatskoj. U svrhu proučavanja otpornosti kukuruza prema rasi 1 Exserohilum turcicum posijan je 2008. godine pokus sa 75 linija različitog porijekla. Linije iz heterotične grupe BSSS su bile osjetljive prema rasi 1 Exserohilum turcicum s prosječnom ocjenom 3,0, dok su linije iz heterotične grupe Lancaster otporne s prosječnom ocjenom 2,0. U drugom pokusu 2012. godine ispitana je otpornost 25 linija kukuruza prema rasi 0 i rasi 1 s ciljem da se utvrdi koje su linije otporne prema obje rase Exserohilum turcicum. Linije Pa875, Bc210K, H102, Bc1411, Pa887P, H111 i H95 otporne su p rema obje rasi 0 i r asi 1 Exserohilum turcicum. Monogenetska otpornost prema rasi 1 unesena je u 4 linije kukuruza (A632, Bc31002, Bc703-19 i Bc14).Northern leaf blight, caused by the fungus Exserohilum turcicum (Pass.) is the most important leaf disease of maize in humid environments. The first maize hybrids in the United States were susceptible to this disease. Therefore, breeding program for resistance was initiated and proved to be very successful. Polygenic and monogenic resistance were used. However, after 15 years of continuous and extensive use of monogenic resistance in the United States occurrence of a new pathotype of E.turcicum. race 2 was reported, which was later named race 1, because Ht 1 gene was not effective against it. New race quickly spread throughout the United States, and later in Croatia. To study maize resistance to race 1 of E. turcicum a trial was planted with 75 lines of different origin in 2008. The lines from the BSSS heterotic group were susceptible to race 1 of Exserohilum turcicum with average rating 3,0, while the lines from the Lancaster heterotic group were resistant with average rating 2,0. In the second experiment in 2012., 25 maize lines were tsted for resistance to race 0 and race 1 to detect lines resistant to both races of Exserohilum turcicum. Lines Pa875, Bc210K, H102, Bc1411, Pa887P, H111 and H95 appear to be resistant to both race 0 and race 1 of Exserohilum turcicum. Monogenic otpornost resistance to race 1 was incorporated into four maize lines (A632, Bc31002, Bc703-19 i Bc14)

Utjecaj skladištenja kontroliranom atmosferom na kvalitetu hrvatskih tradicionalnih sorti jabuke

The aim of this work was to investigate the influence of cold storage at 2 °C for 180 days on water content, total acids, reducing and total sugar, antioxidant activity, polyphenol oxidase activity, and polyphenol profile of three Croatian traditional apple cultivars (‘Kanadska Reneta’, ‘Ilzer Rosenapfel’, ‘Wagener’). A significant variation in polyphenol profile of apple cultivars under investigation was noted. The most represented polyphenols in all apple cultivars were procyanidin B2 followed by chlorogenic acid, epigallocatechin, epicatechin, and phloridzin. After storage, the content of procyanidin B2 and chlorogenic acid was higher, while content of epigallocatechin after storage was lower in all investigated apple cultivars. Water content before storage ranged between 79.17 and 80.76 %, and after storage between 75.62 and 78.56 %. Total acids, polyphenol oxidase activity, and flavonoids had decreased during storage, while reducing and total sugar content was higher after storage. Moreover, after storage, cultivar ‘Kanadska Reneta’ had the highest antioxidant activity measured by both ABTS and DPPH methods, 1.65 and 0.70 mmol trolox kg–1, respectively. A significant variation in polyphenol profile of apple cultivars under investigation was noted. The most represented polyphenols in all apple cultivars were procyanidin B2, followed by chlorogenic acid, epigallocatechin, epicatechin, and phloridzin. After storage, the content of procyanidin B2 and chlorogenic acid was higher, while content of epigallocatechin after storage was lower in all investigated apple cultivars. Overall, it can be concluded that investigated apple cultivars, after storage, preserved most of the antioxidants and functional properties.Cilj ovog rada bio je istražiti utjecaj skladištenja kontroliranom atmosferom na 2 °C tijekom 180 dana na polifenolni profil, sadržaj vode, ukupne kiseline, reducirajuće i ukupne šećere, antioksidacijsku aktivnost i aktivnost polifenol oksidaze triju hrvatskih tradicionalnih sorti jabuke (´Kanadska Reneta’, ‘Ilzer Rosenapfel’, ‘Wagener’). Uočena je značajna varijacija u profilu polifenola ispitivanih sorti jabuke. Najzastupljeniji polifenoli kod svih sorti jabuke bili su procijanidin B2, zatim klorogenska kiselina, epigalokatehin, epikatehin i floridzin. Nakon skladištenja sadržaj procijanidina B2 i klorogenske kiseline bio je veći, dok je sadržaj epigalokatehina nakon skladištenja bio manji kod svih ispitivanih sorti jabuke. Sadržaj vode prije skladištenja kretao se između 79,17 i 80,76 %, a nakon skladištenja između 75,62 i 78,56 %. Tijekom skladištenja došlo je do smanjenja ukupnih kiselina, aktivnosti polifenol oksidaze i udjela flavonoida, dok je sadržaj ukupnih šećera bio veći nakon skladištenja. Štoviše, sorta ‘Kanadska Reneta’ nakon skladištenja imala je najveću antioksidacijsku aktivnost mjerenu ABTS i DPPH metodom, 1,65 odnosno 0,70 mmol trolox/kg–1. Uočena je značajna varijacija u polifenolnom profilu ispitivanih sorti jabuke. Najzastupljeniji polifenoli kod svih sorti jabuke bili su procijanidin B2, zatim klorogenska kiselina, epigalokatehin, epikatehin i floridzin. Nakon skladištenja sadržaj procijanidina B2 i klorogenske kiseline bio je veći, dok je sadržaj epigalokatehina nakon skladištenja bio niži kod svih ispitivanih sorti jabuke. Sveukupno se može zaključiti da su ispitivane sorte jabuka nakon skladištenja sačuvale najveći dio antioksidativnih i funkcionalnih svojstava