74 research outputs found

    Utjecaj ekstrakcije potpomognute mikrovalovima na udjel fenolnih spojeva i antioksidacijski kapacitet cvijetova trnine

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    This research was undertaken to investigate the influence of extraction parameters during microwave-assisted extraction on total phenolic content, total flavonoids, total hydroxycinnamic acids and total flavonols of blackthorn flowers as well as to evaluate the antioxidant capacity by two different methods (2,2-diphenyl-1 picrylhydrazyl free radical scavenging capacity and ferric reducing antioxidant power assays). The investigated extraction parameters were: solvent type and volume fraction of alcohol in solvent (50 and 70 % aqueous solutions of ethanol and methanol), extraction time (5, 15 and 25 min) and extraction temperature (40, 50 and 60 °C) controlled by microwave power of 100, 200 and 300 W. Multivariate analysis of variance (MANOVA) was used to evaluate the differences at a 95 % confidence level (p≤0.05). The obtained results show that aqueous solution of ethanol was more appropriate solvent for extraction of phenolic compounds (total flavonoids, total hydroxycinnamic acids and total flavonols) than aqueous solution of methanol. The amount of phenolic compounds was higher in 70 % aqueous solution of ethanol or methanol, while higher antioxidant capacity was observed in 50 % aqueous solution of methanol. Higher temperature of extraction improved the amount of phenolic compounds and also antioxidant capacity determined by 2,2-diphenyl-1-picrylhydrazyl free radical scavenging capacity assay. Extensive duration of extraction (15- to 25-minute interval) has a significant effect only on the increase of total phenolic content, while specific phenolic compound content and antioxidant capacity were the highest when microwave extraction time of 5 min was applied.Ovo je istraživanje provedeno radi ispitivanja utjecaja parametara ekstrakcije potpomognute mikrovalovima na udjele ukupnih fenola, flavonoida, hidroksicimetnih kiselina i flavonola i određivanja antioksidacijskog kapaciteta cvijetova trnine pomoću dviju različitih metoda (DPPH i FRAP). Ispitani su sljedeći ekstrakcijski parametri: tip otapala i volumni udjel alkohola u otapalu (50 i 70 %-tna vodena otopina etanola i metanola), vrijeme ekstrakcije (5, 15 i 25 min) te temperatura ekstrakcije (40, 50 i 60 °C) održavana snagom mikrovalova od 100, 200 i 300 W. Multivarijantna analiza varijance (MANOVA) korištena je za procjenu razlika na razini pouzdanosti od 95 % (p≤0.05). Dobiveni rezultati pokazuju da je vodena otopina etanola prikladnije otapalo za ekstrakciju fenolnih spojeva (ukupnih flavonoida, hidroksicimetne kiseline i flavonola) od vodene otopine metanola. Udjel fenolnih spojeva bio je veći u 70 %-tnim vodenim otopinama etanola i metanola, dok je antioksidacijski kapacitet ekstrakata u 50 %-tnoj vodenoj otopini metanola bio veći. Viša temperatura ekstrakcije metanola povećala je udjel fenolnih spojeva i antioksidacijski kapacitet određen pomoću DPPH metode. Produljeno trajanje ekstrakcije (u intervalu od 15 do 25 min) bitno je utjecao samo na povećanje udjela ukupnih fenola, dok su udjel specifičnih fenolnih spojeva i antioksidacijski kapacitet bili najveći pri vremenu ekstrakcije od 5 min

    Scientific Challenges in Performing Life-Cycle Assessment in the Food Supply Chain

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    This paper gives an overview of scientific challenges that occur when performing life-cycle assessment (LCA) in the food supply chain. In order to evaluate these risks, the Failure Mode and Effect Analysis tool has been used. Challenges related to setting the goal and scope of LCA revealed four hot spots: system boundaries of LCA; used functional units; type and quality of data categories, and main assumptions and limitations of the study. Within the inventory analysis, challenging issues are associated with allocation of material and energy flows and waste streams released to the environment. Impact assessment brings uncertainties in choosing appropriate environmental impacts. Finally, in order to interpret results, a scientifically sound sensitivity analysis should be performed to check how stable calculations and results are. Identified challenges pave the way for improving LCA of food supply chains in order to enable comparison of results

    Simple and rapid method for the simultaneous determination of cholesterol and retinol in meat using normal-phase HPLC technique

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    A direct saponification and normal-phase high-performance liquid chromatography (NP-HPLC) procedure was developed for simultaneous determination of cholesterol and retinol in meat. A normal-phase silica column fitted with diode array detection at 208 nm for cholesterol and fluorescence detection (λ-excitation 344 nm/λ-emission 472 nm) for retinol, with mobile phase consisting of 2% (v/v) 2-propanol in n-hexane was used. Cholesterol was eluted at 10 min and retinol at 12.66 min. High linearity (R2 > 0.9996 for both compounds) in calibration range was obtained. The LOD and LOQ values show the high sensitivity of the developed methodology for simultaneous determination of cholesterol and retinol in meat. Recovery results obtained in this study (98.67–102.14% for cholesterol and 91.72–98.27% for retinol) were between AOAC recommendations to validated method and were comparable to most recent studies in precision and accuracy. In addition, the present method showed high repeatability and reproducibility. As a general conclusion, the results indicate that the direct saponification, extraction, and HPLC analysis is an adequate method for cholesterol and retinol analysis in meat samples.Xunta de Galicia | Ref. IN607B 2016/2

    Utjecaj klimatskih uvjeta, sortnih karakteristika i postupaka proizvodnje na udjele tokoferola, plastokromanola-8 i pigmenta u lanenom ulju

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    The objective of this study is to compare the influence of genotype, environmental conditions and processing methods after maturation and harvesting of four varieties of flaxseed (Altess, Biltstar, Niagara and Oliwin) on the levels of tocochromanols, carotenoids and chlorophyll in flaxseed oil. Samples were produced by cold pressing of dry seeds and seeds heated for 30 min at 60 °C. Temperature, sunshine and rainfall were primary environmental conditions included. Grand mean of mass fraction of γ-tocopherol was (522±29), of plastochromanol-8 (305±2) and total tocochromanols (831±3) mg per kg of oil. The highest levels of these compounds and strongest antioxidant activity were found in cold-pressed oil of Biltstar variety. During seed maturation, levels of γ-tocopherol and plastochromanol-8 increased with average temperature and total sunshine and decreased with total rainfall. Fifth week after flowering was identified as the maturation period with best climate conditions to achieve optimal tocochromanol content. Grand mean of mass fraction of carotenoids expressed as β-carotene was (1.83±0.01) and of chlorophyll expressed as pheophytin a (0.43±0.10) mg per kg of oil. Altess variety had the highest levels of pigments. Antioxidant activity decreased with the increase of chlorophyll, while correlations with carotenoids were not determined. Generally, oil obtained by cold pressing had higher levels of tocochromanols and lower levels of pigments but similar antioxidant activity to the oil after seed conditioning. The results of this study contribute to identifying the flaxseed variety that is the best for oil production with the highest antioxidant activity and nutritive value, and provide better understanding of tocochromanol biosynthesis depending on different climate conditions.Svrha je ovoga rada bila ispitati utjecaj genotipa, uvjeta okoliša i različitih načina obrade nakon dozrijevanja i žetve četiri sorte lana (Altess, Biltstar, Niagara i Oliwin) na udjele tokokromanola, karotenoida i klorofila u ulju dobivenom od tih sorata. Uzorci su proizvedeni hladnim prešanjem i kondicioniranjem sjemenki lana tijekom 30 min na 60 °C. Praćeni su glavni okolišni čimbenici, i to temperatura, padaline i insolacija. Prosječni udjel γ-tokoferola u uzorcima bio je (522±29) mg/kg, plastokromanola-8 (305±2) mg/kg, a ukupnih tokokromanola (831±3) mg/kg. Hladno prešano ulje sorte Biltstar imalo je najveći udjel tih spojeva te najizraženiji antioksidacijski učinak. Udjeli γ-tokoferola i plastokromanola-8 povećavali su se s porastom prosječne temperature i trajanjem insolacije, a smanjivali s povećanjem količine oborina u periodu sazrijevanja sjemena. Utvrđeno je da su za postizanje optimalnog udjela tokokromanola u ulju najbolji klimatski uvjeti bili pet tjedana nakon cvatnje. Prosječni udjel karotenoida u svim uzorcima ulja, izražen kao β-karoten, bio je (1.83±0.01) mg/kg, a klorofila, izražen kao feofitin a, (0.43±0.10) mg/kg. Ulja dobivena od sorte Altess imala su najveće udjele pigmenata. Antioksidacijska aktivnost ulja smanjivala se s povećanjem udjela klorofila, dok udjel karotenoida nije imao bitan utjecaj. Hladno prešana ulja imala su veće udjele tokokromanola i manje udjele pigmenata od ulja dobivenih od kondicioniranih sjemenki, no slična antioksidacijska svojstva. Ovo je istraživanje omogućilo identifikaciju najbolje sorte lana za dobivanje ulja najveće antioksidacijske aktivnosti i hranjive vrijednosti, što pridonosi spoznajama o utjecaju klimatskih uvjeta na biosintezu tokokromanola

    Primjena ekstrakta proteina sirutke u proizvodnji smrznutog mliječnog deserta

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    The aim of this work was to substantiate the use of whey protein extract (WPE), a by-product of dairy industry, combined with different berry purees in the formulation of a whipped frozen dairy dessert (WFDD). After freezing, the swelling ability of WPE decreased significantly while at higher temperatures of the dispersion medium, the degree of swelling increased. A mixture containing 55±2 % WPE and 45±2 % milk presented a homogeneous consistency while the further processing did not improve the structure of the mixture. Final formulations of WFDD containing different berry purees (i.e. 10 % black¬currant puree, 25 % cherry puree, or 30 % strawberry puree) were proposed for which the nutritional facts were calculated. Recommended shelf life of the developed desserts at -18 °C is suggested to be 20 days. Regulatory requirements and recommendations for the production of WFDD in an industrial scale were also developed. Recommended shelf life of the developed desserts at -18 °C is suggested to be 20 days. In conclusion, a WFDD was developed using WPE as a by-product of dairy industry.Svrha ovog rada bila je ispitati mogućnost primjene kombinacije pirea bobičastog voća i ekstrakta proteina sirutke (WPE), inače nusproizvoda mljekarske industrije, u proizvodnji smrznutog mliječnog deserta (WFDD). Nakon smrzavanja, sposobnost bubrenja WPE značajno je pala, međutim pri višim temperaturama medija za raspršivanje sposobnost bubrenja ponovno je rasla. U pogledu konzistencije najboljom se pokazala mješavina koja se sastojala od 55±2 % WPE i 45±2 % mlijeka te daljnja prera¬da nije rezultirala poboljšanjem teksture mješavine. Za konačne recepture WFDD s različitim udjelima pirea bobičastog voća (10 % pirea crnog ribizla, 25 % pirea višnje ili 30 % pirea jagode) napravljeni su izračuni prehrambene vrijednosti. Preporučeni rok trajanja za proizvedene deserte iznosio je 20 dana na temperaturi čuvanja -18 °C. Osim toga, uspostavljeni su zahtjevi sukladno zakonskim propisima kao i odgovarajuće preporuke za proizvodnju WFDD u industrijskom mjerilu. Zaključno, razvoj proizvodnje WFDD uključuje primjenu nusprizvoda mljekarske industrije - WPE

    Primjena ekstrakta proteina sirutke u proizvodnji smrznutog mliječnog deserta

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    The aim of this work was to substantiate the use of whey protein extract (WPE), a by-product of dairy industry, combined with different berry purees in the formulation of a whipped frozen dairy dessert (WFDD). After freezing, the swelling ability of WPE decreased significantly while at higher temperatures of the dispersion medium, the degree of swelling increased. A mixture containing 55±2 % WPE and 45±2 % milk presented a homogeneous consistency while the further processing did not improve the structure of the mixture. Final formulations of WFDD containing different berry purees (i.e. 10 % black¬currant puree, 25 % cherry puree, or 30 % strawberry puree) were proposed for which the nutritional facts were calculated. Recommended shelf life of the developed desserts at -18 °C is suggested to be 20 days. Regulatory requirements and recommendations for the production of WFDD in an industrial scale were also developed. Recommended shelf life of the developed desserts at -18 °C is suggested to be 20 days. In conclusion, a WFDD was developed using WPE as a by-product of dairy industry.Svrha ovog rada bila je ispitati mogućnost primjene kombinacije pirea bobičastog voća i ekstrakta proteina sirutke (WPE), inače nusproizvoda mljekarske industrije, u proizvodnji smrznutog mliječnog deserta (WFDD). Nakon smrzavanja, sposobnost bubrenja WPE značajno je pala, međutim pri višim temperaturama medija za raspršivanje sposobnost bubrenja ponovno je rasla. U pogledu konzistencije najboljom se pokazala mješavina koja se sastojala od 55±2 % WPE i 45±2 % mlijeka te daljnja prera¬da nije rezultirala poboljšanjem teksture mješavine. Za konačne recepture WFDD s različitim udjelima pirea bobičastog voća (10 % pirea crnog ribizla, 25 % pirea višnje ili 30 % pirea jagode) napravljeni su izračuni prehrambene vrijednosti. Preporučeni rok trajanja za proizvedene deserte iznosio je 20 dana na temperaturi čuvanja -18 °C. Osim toga, uspostavljeni su zahtjevi sukladno zakonskim propisima kao i odgovarajuće preporuke za proizvodnju WFDD u industrijskom mjerilu. Zaključno, razvoj proizvodnje WFDD uključuje primjenu nusprizvoda mljekarske industrije - WPE

    The perspective of Croatian old apple cultivars in extensive farming for the production of functional foods

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    The Republic of Croatia has a long tradition of fruit growing due to its geographical location, climatic conditions, and high quality of fruit crops, especially apple fruits. Apples can be used for the formulation of functional foods either in processed form (e.g., juice), or as a by-product (e.g., apple pomace). However, there is a growing demand for functional foods derived from ancient and traditional plant sources as they are recognized as a very valuable source of health-promoting bioactive ingredients. Similarly, old apple cultivars (Malus domestica Borkh.) are characterized by good morphological and pomological properties, less need for chemicals during cultivation and the higher share of biologically active compounds (BACs) with better sensory acceptability compared to commercial cultivars. However, their nutritional and biological potential is underestimated, as is their ability to be processed into functional food. The importance in preserving old apple cultivars can also be seen in their significance for improving the nutritional composition of other apple cultivars through innovative cultivation strategies, and therefore old local apple cultivars could be of great importance in future breeding programs.Hrvatska Zaklada za Znanost | Ref. IP-2019-04-2105European Commission | Ref. KK.01.1.1.04.009

    Utjecaj sorte i industrijske obrade na sastav polifenola u koncentriranom soku višnje (Prunus cerasus L.)

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    The objective of this study is to investigate the infl uence of cultivar and industrial processing on total polyphenols, anthocyanins, hydroxycinnamic acids and antioxidant activity in concentrated sour cherry (Prunus cerasus L., cvs. Marasca and Oblačinska) juices. Samples were collected during four processing steps: from fresh fruit prior to processing, then from pressed, fi ltered and concentrated juices. The content of total phenols was the same in both cultivars, but antioxidant activity (Oblačinska>Marasca) and total monomeric anthocyanins (Marasca>Oblačinska) diff ered. All processing steps significantly influenced the content of total phenols, total monomeric anthocyanins and antioxidant activity. In all samples four major anthocyanins were identifi ed by HPLC with UV/VIS PDA detector, listed in the descending order based on their abundance: cyanidin-3-glucosylrutinoside, cyanidin-3-rutinoside, cyanidin-3-sophoroside and cyanidin-3-glucoside. Marasca cv. contained more total anthocyanins, and contents of cyanidin-3-sophoroside and cyanidin-3-glucosylrutinoside. The content of total hydroxycinnamic acids was also higher in Marasca than Oblačinska cv. Aft er processing, the concentration of all identifi ed anthocyanins increased in both cultivars. Majority of the highest values of polyphenols were detected in the juice aft er pressing. The content of polyphenols and their antioxidant activity were considerably stable during industrial processing to concentrated juice. Although Marasca had higher polyphenolic content than Oblačinska, both cultivars showed promising industrial potential for processing to concentrated juice.Svrha je ovoga rada bila ispitati utjecaj sorte i industrijske obrade na ukupne polifenole, antocijanine, hidroksicinamične kiseline i antioksidacijsku aktivnost u koncentriranom soku višnje (Prunus cerasus L., sorte Maraska i Oblačinska). Uzorci su prikupljeni tijekom četiri koraka obrade: iz svježeg voća prije prerade, te iz prešanog, filtriranog i koncentriranog soka. Ukupni je udjel fenola bio jednak u obje sorte, ali su se antioksidacijska aktivnost (Oblačinska>Maraska) i ukupni udjel monomernih antocijanina razlikovali. Svi su koraci obrade bitno utjecali na ukupni udjel fenola, monomernih antocijanina i antioksidacijsku aktivnost soka višnje. Visokodjelotvornom tekućinskom kromatografijom (HPLC) uz UV/VIS PDA detekciju u svim su uzorcima identificirana četiri glavna antocijanina, i to redom od najzastupljenijeg: cijanidin-3-glukozilrutinozid, cijanidin-3-rutinozid, cijanidin-3-soforozid i cijanidin-3-glukozid. Kultivar Maraska sadržavao je više antocijanina, te veće udjele cijanidin-3-soforozida i cijanidin-3-glukozilrutinozida. Ukupni je udjel hidroksicinamičnih kiselina također bio veći u sorti Maraska nego u sorti Oblačinska. Koncentracija se svih identificiranih antocijanina povećala u obje sorte nakon obrade. Najveći su udjeli polifenola uglavnom izmjereni u soku nakon prešanja. Udjeli polifenola i njihov antioksidacijski učinak bili su uglavnom isti tijekom ugušćivanja soka. Iako je sorta Maraska imala veći udjel polifenola od sorte Oblačinska, obje su sorte prikladne za industrijsku proizvodnju koncentriranog soka od višnje

    The link between the phenolic composition and the antioxidant activity in different small berries: A metabolomic approach

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    Small berries have become an attractive topic of research due to their high content in phenolic compounds and reported antioxidant activity. However, there are currently few reports on the deep characterization of their polyphenol composition. Five kinds of berries (raspberry, blackberry, blueberry, mulberry and black chokeberry) were studied to compare the antioxidant activities and polyphenol compositions of both berry juice and pomace (by-products in processing). Results showed that pomaces were more potent antioxidants than juices, especially those that originated from red raspberry. The polyphenol contents in pomaces ranged from 137 to 222 mg/g, this was higher than juices that ranged from 2.75 to 8.88 mg/g, with mulberry accounting for the highest content. The main compounds in pomaces were phenolic compounds with different relative contents found by UPLC-MS/MS. A total of 568 compounds were identified, including 238 flavonoids and 131 phenolic acids. PCA, HCA and OPLS-DA analyses were performed to find similarities on the polyphenol and metabolomic profile of the sampled berries. This analysis unveiled that all studied berries presented a significantly different polyphenol profile, on which raspberry and blackberry were the most similar. Results suggested that berry pomaces can be valuable sources of phenolic compounds of which the major components are anthocyanins and phenolic acids, with potential applications as antioxidant food additives, or raw materials for pharmaceuticals, nutraceuticals, and cosmetics.Provincial Major Scientific and Technological Innovation Project of Shandong | Ref. 2021SFGC0904; 2021TZXD001; 2021TZXD004Natural Science Foundation of Shandong, China | Ref. ZR2020QD103; ZR2020MH401; ZR2021QH351Agriculture Scientific and Technological Innovation Program of Shandong Academy of Agriculture Sciences | Ref. CXGC2022B07; CXGC2022A04)Innovation Ability Improvement Project for Technology-Based Small and Medium-sized Enterprises of Shandong, China | Ref. 2022TSGC2002Xunta de Galicia | Ref. ED431F 2020/12Ministerio de Ciencia e Innovación | Ref. RYC-2017-22891Universidade de Vigo/CISUG
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