Kvaliteta upotrebljivosti ambalaže od recikliranih papira

Cilj diplomskog rada je ispitati kako se provodi kontrola kvalitete u hrvatskom poduzeću za proizvodnju ambalaže od oblikovane pulpe – Hartmann. Teorijskim dijelom diplomskog rada opisane su vrste ambalaže i njene funkcije te karakteristike procesa pakiranja. Rad opisuje i postupak proizvodnje te proces kontrole kvalitete ambalaže od oblikovane pulpe. Proces kontrole kvalitete počinje ulaznom kontrolom, odnosno kontrolom sirovina. Nakon toga slijedi kontrola proizvodnog procesa koja obuhvaća analizu papirne mase, a na kraju slijedi kontrola gotovih proizvoda. U eksperimentalnom dijelu rada provedena je kontrola kvalitete u vremenskom razdoblju od pet dana, kroz tri radne smjene, a izvedena je prema radnim uputama tvrtke. Dobiveni rezultati ubilježeni su u obrasce Analiza mase i Analiza gotovih proizvoda

The influence of the process parameters and the addition of antioxidants on the utilization and stability of plum kernel oil

Koštica šljive je nusproizvod prehrambene industrije iz kojeg se prešanjem može dobiti jestivo ulje, a njegova konzumacija može smanjiti rizik obolijevanja od kroničnih bolesti. Koštice šljive pribavljene s područja Slavonije i Baranje prešane su na pužnoj preši te je dobiveno sirovo ulje. Sedimentacijom i filtracijom dobiveno je hladno prešano ulje koštice šljive kojemu su određeni osnovni parametri kvalitete: peroksidni broj, slobodne masne kiseline, udio vode i udio netopljivih nečistoća. Prilikom prešanja ispitivao se utjecaj procesnih parametara: temperature zagrijavanja glave preše, veličina otvora glave preše i frekvencija elektromotora na iskorištenje ulja. Ispitan je i utjecaj dodatka antioksidansa na oksidacijsku stabilnost ulja primjenom Testa održivosti na 98 °C. Korišteni su prirodni antioksidansi ekstrakt zelenog čaja, ekstrakt ružmarina i eterično ulje primorskog vriska te sintetski antioksidans oktil-galat. Rezultati pokazuju da ispitivani procesni parametri hladnog prešanja utječu na iskorištenje ulja. Dodatkom prirodnih antioksidanasa postignuta je bolja zaštita ulja od oksidacijskog kvarenja, nego dodatkom sintetskog antioksidansa. Eterično ulje primorskog vriska imalo je najbolji antioksidacijski utjecaj.Plum kernel is byproduct of the food industry which can be used to produce edible oil through pressing. Also, its consumption is associated with reduced risk of chronic diseases. Kernels from territory of Slavonia and Baranja were used for production of oil. Raw oil was produced by using screw pressing and cold-pressed oil was obtained by sedimentation and filtration. Quality parameters such as peroxide value, free fatty acids, moisture content and insoluble impurities were determined. Aim of this study was to examine the influence of process parameters: press head temperature at cake exit, size of the press head hatch and electromotor frequency on the utilization of oil. Oxidative stability of oil with added antioxidants was determined by the Test of sustainability at 98°C. Natural antioxidants such as green tea extract, rosemary extract, winter savory essential oil and synthetic antioxidant octyl gallate were used. Results showed that natural antioxidants have greater protection of oil in comparison to synthetic antioxidants. Winter savory essential oil had the best antioxidant effect

Antioxidant capacity and physicochemical parameters of rape honey (Brassica sp.)

Zadatak ovog rada bio je karakterizirati med od uljane repice (Brassica sp.) s naglaskom na antioksidativni kapacitet. Antioksidativni kapacitet meda ovisi prvenstveno o njegovu botaničkom podrijetlu, a najčešće se povezuje s udjelom fenola i bojom. Od fizikalno-kemijskih parametara određeni su: udio vode, električna provodnost, boja, aktivnost dijastaze, udio HMF-a, omjer fruktoze i glukoze te njihov zbroj. Udio fenola određen je modificiranom Folin-Ciocalteu metodom dok je antioksidativni kapacitet određen FRAP i DPPH metodama. Rezultati analiza pokazali su da med od uljane repice karakterizira nizak omjer fruktoze i glukoze s prosječnom vrijednosti 1,00±0,03 te da spada u kategoriju jako svijetlo žutih medova prema Pfund-ovoj skali (prosječna vrijednost 37,5±7,9 mm Pfund). Udio ukupnih fenola nalazio se u rasponu 108,2-152,6 mg galne kiseline/kg meda, dok je antioksidativni kapacitet određen FRAP metodom bio 144,6-232,3 μM Fe(II), a onaj određen DPPH metodom 17,51-29,09 mg/ml.The aim of this study was characterisation of rape honey (Brassica sp.) with emphasis on antioxidant capacity. Antioxidant capacity of honey primarily depends on its botanical origin and generally is correlated with phenolic content and honey colour. Following physicochemical parameters were determined: water content, electrical conductivity, colour, diastase activity, HMF content, fructose (F) and glucose (G) ratio and their sum. Total phenolic content was determined by modified Folin-Ciocalteu method while antioxidant capacity of honey was determined by FRAP and DPPH methods. Results showed that rape honey has low F/G ratio with average value of 1,00±0,03 and according to the Pfund scale belongs to category extra light amber (the average value 37,5±7,9 mm Pfund). Total phenolic content was 108,2-152,6 mg gallic acid/kg of honey, while antioxidant capacity determined by FRAP method was 144,6-232,3 μM Fe(II) and antioxidant capacity which was determined by DPPH method was 17,51-29,09 mg/ml

Macroalgae in the Food Industry – Opportunities and Challenges

The industry recognized macroalgae not only as a very important source of bioactive compounds but also as ‘super-foods’ due to their nutritional value. They can be used as raw food acting as an alternative source of vegetable proteins, fibres, vitamins and minerals but also they can be commercialized in many forms and incorporated in other food products. The aim of this review is to emphasize the importance of macroalgae application in the food industry. They are already used for different purposes, from food products to medicine. Among mentioned compounds, the special emphasis was given to macroalgal polysaccharides that are present in many products consumed on daily basis. Their importance in texture stability of the food products, as well as their functional properties are evaluated

The production and stabilization of cold-pressed plum kernel oil

Postupkom hladnog prešanja iz koštice šljive (Prunus domestica L.) dobije se kvalitetno jestivo ulje. Cilj ovog rada bio je ispitati utjecaj procesnih parametara prešanja koštice šljive na efikasnost proizvodnje hladno prešanog ulja te njegovu kvalitetu. Prilikom prešanja mijenjani su sljedeći procesni parametri: frekvencija elektromotora (brzina pužnice), temperatura zagrijavanja glave preše i nastavak za izlaz pogače. Prešanje je provedeno s kontinuiranom pužnom prešom. Primjenom standardnih metoda određeni su osnovni parametri kvalitete proizvedenog hladno prešanog ulja. Ispitan je i utjecaj dodatka antioksidanasa na oksidacijsku stabilnost ulja primjenom Testa održivosti na 98 °C. Korišteni su sljedeći prirodni antioksidansi: ekstrakt zelenog čaja, ekstrakt ružmarina i eterično ulje primorskog vriska te sintetski antioksidans oktil galat. Rezultati ispitivanja pokazuju da procesni parametri hladnog prešanja značajno utječu na iskorištenje ulja koštice šljive. Veće iskorištenje sirovog ulja i hladno prešanog ulja postignuto je kod temperature zagrijavanja glave preše 100 °C, frekvencije elektromotora 35 Hz i nastavka za izlaz pogače 10 mm. Dodatkom prirodnih antioksidanasa postignuta je bolja zaštita ulja od oksidacijskog kvarenja nego dodatkom sintetskog antioksidansa. Eterično ulje primorskog vriska pokazalo je najbolji antioksidacijski utjecaj.The cold pressing of the plum kernel (Prunus domestica L.) is used to obtain high-quality edible oil. The aim of this study was to investigate the influence of process parameters of pressing plum kernel on the efficiency of production of cold-pressed oil and its quality. Following process parameters were investigated: electromotor frequency, temperature of head presses, and nozzle size. Pressing was carried out with a continuous screw press. Using standard methods, the basic quality parameters of produced cold pressed oil were determined. Oxidative stability of oil with added antioxidants was determined by the test of sustainability at 98°C. Natural antioxidants such as green tea extract, rosemary extract, winter savory essential oil and synthetic antioxidant octyl gallate were used. The results showed that the process parameters of cold pressing had a significant impact on the yield of plum kernel oil. Higher yield of crude oil and cold-pressed oil was obtained at a temperature of heating head presses 100°C, electromotor frequency of 35 Hz and using nozzle size of 10 mm. The results showed that natural antioxidants have greater protection of oil in comparison to synthetic antioxidants. Winter savory essential oil had the best antioxidant effect

Macroalgae in the Food Industry – Opportunities and Challenges

The industry recognized macroalgae not only as a very important source of bioactive compounds but also as ‘super- foods’ due to their nutritional value. They can be used as raw food acting as an alternative source of vegetable proteins, fibres, vitamins and minerals but also they can be commercialized in many forms and incorporated in other food products. The aim of this review is to emphasize the importance of macroalgae application in the food industry. They are already used for different purposes, from food products to medicine. Among mentioned compounds, the special emphasis was given to macroalgal polysaccharides that are present in many products consumed on daily basis. Their importance in texture stability of the food products, as well as their functional properties are evaluated

In Vivo and In Vitro Antioxidant Activity of Less Polar Fractions of Dasycladus vermicularis (Scopoli) Krasser 1898 and the Chemical Composition of Fractions and Macroalga Volatilome

The present research is a comprehensive investigation of Dasycladus vermicularis (Scopoli) Krasser 1898 from the Adriatic Sea (Croatia) regarding volatilome–volatile organic compounds (VOCs, mostly nonpolar compounds) and less polar nonvolatile compounds for the first time. Headspace solid-phase microextraction (HS-SPME) and hydrodistillation (HD) were used showing the great volatilome variability among fresh (HS-FrDV and HD-FrDV) and dried (HS-DrDV and HD-DrDV) samples after GC–MS analysis. Aromatic aldehydes were dominant in both fresh and air-dried HS samples with benzaldehyde as the most abundant in fresh samples and decreasing 2.7–3.7 times after drying together with 2-phenylbut-2-enal that was not present after drying. Aliphatic compounds (unsaturated hydrocarbons in HS-FrDV ; saturated hydrocarbons in HS-DrDV) were also present. C11-hydrocarbons (dictyopterpene C’ and dictyopterpene D’) were detected in HS-FrDV. (E)- Phytol was the most dominant compound in HD-FrDV and HD- DrDV. Diterpene alcohols (cembra-4, 7, 11, 15- tetraen-3-ol and (Z)-falcarinol) and sesquiterpene alcohol, cubenol, were dominant in HD-FrDV, and their abundance decreased after drying. C13- norisoprenoides (alpha-ionone and beta -ionone) increased after drying. Aliphatic compounds were present in both HD-FrDV and HD-DrDV samples. The less polar nonvolatile compounds in the obtained fractions F3 and F4 were analysed and identified by UHPLC-ESI(+)-HRMS. Identified compounds belonged to a group of pigments (7 compounds), fatty acid derivatives (13 compounds), as well as steroids and terpenes (10 compounds). Porphyrinbased compounds (C55H74N4O5–7), xanthophylls, sphingolipid compounds, fatty acid amides, and phytosterols represented the majority of identified compounds. By implementing both in vitro and in vivo assays for antioxidant activity determination, F3 showed a higher activity than F4. Inhibitory concentrations (IC50) for F3 and F4 were 498.00 ± 0.01 µg/mL and 798.00 ± 0.81 µg/mL, respectively, while a 1.5-fold reduction in the ROS level was observed after pre-treatment of zebrafish larvae with 45 µg/mL of F3

Extraction of Bioactive Compounds from Tobacco Waste using Deep Eutectic Solvents

Duhanski otpad je kruti otpad, a njegove vrste međusobno se razlikuju po granulaciji i mjestu izdvajanja u procesu proizvodnje. Cilj ovog rada bio je istražiti učinkovitost eutektičkih otapala u ekstrakciji bioaktivnih komponenti iz duhanskog industrijskog otpada (refabrikat, rebro i prašina). Ispitan je utjecaj procesnih parametara (vrijeme miješanja, temperatura i udio vode u otapalu) na svojstva samog ekstrakta (ukupne fenole, antiradikalnu aktivnost, udio klorogenske kiseline i rutina). Metodom odzivne površine određeni su optimalni parametri ekstrakcije (30 min, 70 °C, 29,99 % vode). Provedeno istraživanje ogleda se u maksimalnom iskorištavanju nusproizvoda duhanske industrije, a rezultira visokovrijednim ekstraktima koji se mogu implementirati u druge procese i proizvode. Ovo djelo je dano na korištenje pod licencom Creative Commons Imenovanje 4.0 međunarodna.Tobacco waste is a solid waste highly diverse in granulation and point of separation in the manufacturing process. The objective of this study was to investigate the efficacy of eutectic solvents in the extraction of bioactive compounds from tobacco waste. Influence of extraction parameters on the properties of the obtained extracts (total phenol, antioxidant activity, chlorogenic acid, and rutin) has been determined. Using response surface methodology, optimal parameters were defined (30 min, 70 °C, 29.99 % water). The meaning of the proposed research is reflected in the maximum utilization of the tobacco by-product in order to obtain extracts that can be implemented in other products and processes. This work is licensed under a Creative Commons Attribution 4.0 International License