Danijela Samac

Dr. Danijela Samac


Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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14 September 2022 in Applied Sciences
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ĐKĐurđica Kovačić
Đurđica Kovačić
Zdenko LončarićZdenko Lončarić
Zdenko Lončarić
JJJurica Jović
Jurica Jović
DSDanijela Samac
Danijela Samac
BPBrigita Popović
Brigita Popović
MTMarina Tišma
Marina Tišma
The implementation of sustainable agro-energy systems that integrate crop, livestock, and bioenergy production is attracting increasing interest from farmers. Livestock produces large amounts of animal manure which can serve as organic fertilizer for crops and pasture growth. However, the nutrients contained in manure can adversely affect air, water, and soil quality and pose a public health risk if not handled properly. Existing manure management practices vary widely on a global scale. Researchers are striving to identify appropriate manure management practices with the aim of environmental protection. Anaerobic digestion of manure and subsequent digestate (DG) processing technologies have been proposed to stabilize manure so that it can be safely used for land applications. DG, which represents digested substrate removed from the anaerobic reactor after recovery of biogas, is a rich source of N, P, K, and S, various micronutrients, and organic matter, the addition of which to the soil can stimulate soil microbial biomass metabolic activities thus improving soil ecosystem function. However, the optimal fertilization properties of DG can be lost if it is neither fully stabilized nor contains biodegradable materials. To overcome these problems, various processing technologies can be used to convert DG into value-added by-products. Composting has been proposed as one such preferred post-treatment that can convert DG into mature, stable, safe, humus- and nutrient-rich compost. Other processing technologies such as thermal drying, gasification, hydrothermal carbonization, pyrolysis, membrane filtration, struvite precipitation, ammonia stripping, and evaporation have also been proposed for DG processing and nutrient recovery from DG. The objective of this review paper was to provide an overview of the current state of the art in DG management regulations and practices and to provide an update on the various processes that have been developed to meet DG stabilization requirements, with a focus on composting as one of the preferred solutions.

18 January 2024 in Agriengineering
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ĐKĐurđica Kovačić
Đurđica Kovačić
Dorijan RadočajDorijan Radočaj
Dorijan Radočaj
DSDanijela Samac
Danijela Samac
Mladen JurišićMladen Jurišić
Mladen Jurišić
The research on lignocellulose pretreatments is generally performed through experiments that require substantial resources, are often time-consuming and are not always environmentally friendly. Therefore, researchers are developing computational methods which can minimize experimental procedures and save money. In this research, three machine learning methods, including Random Forest (RF), Extreme Gradient Boosting (XGB) and Support Vector Machine (SVM), as well as their ensembles were evaluated to predict acid-insoluble detergent lignin (AIDL) content in lignocellulose biomass. Three different types of harvest residue (maize stover, soybean straw and sunflower stalk) were first pretreated in a laboratory oven with hot air under two different temperatures (121 and 175 °C) at different duration (30 and 90 min) with the aim of disintegration of the lignocellulosic structure, i.e., delignification. Based on the leave-one-out cross-validation, the XGB resulted in the highest accuracy for all individual harvest residues, achieving the coefficient of determination (R2) in the range of 0.756–0.980. The relative variable importances for all individual harvest residues strongly suggested the dominant impact of pretreatment temperature in comparison to its duration. These findings proved the effectiveness of machine learning prediction in the optimization of lignocellulose pretreatment, leading to a more efficient lignin destabilization approach.

30 March 2021 in Foods
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JNJosip Novoselec
Josip Novoselec
ŽŠŽeljka Klir Šalavardić
Željka Klir Šalavardić
DSDanijela Samac
Danijela Samac
MRMario Ronta
Mario Ronta
ZSZvonimir Steiner
Zvonimir Steiner
ZAZvonko Antunović
Zvonko Antunović
The aim of this research was to investigate the slaughter indicators, carcass measures, and meat quality of lambs fattened with spelt. Lambs consumed various feed mixtures (1000 g day−1 lamb−1): I—control group; II—group with 10% dehulled spelt; III—group with 20% dehulled spelt. In the blood, the concentrations of minerals (calcium, phosphorus, magnesium, and iron), biochemical parameters (urea, glucose, total proteins, albumin, globulin, cholesterol, triglycerides, high-density lipoprotein, low-density lipoprotein, ß-hydroxybutyrate, non-esterified fatty acids, glutathione peroxidase, and superoxide dismutase), and hepatic enzymes (alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma-glutamyltransferase, and creatine kinase) were determined. After slaughter, carcass development was measured. Samples of musculus semimembranosus were taken, of which the physical properties were analyzed. By analyzing the production properties of the lambs, we found that the slaughter characteristics of the lamb carcasses and the physical properties of the lamb meat as well as most biochemical indicators and enzymes did not significantly differ. The concentrations of albumin were increased in the groups with 10% and 20% spelt, as was the activity of alkaline phosphatase in the group with 20% spelt. The presented results indicate that spelt is an appropriate ingredient in the diet for weaned lambs.

1 January 2018 in Meso
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ĐSĐuro Senčić
Đuro Senčić
DSDanijela Samac
Danijela Samac
Nährwert von Trockenschinken und luftgetrockneten Rohschinken (Pršut) Aufgrund des hohen Gehalts an Speisesalz und Cholesterin sowie Rauchbestandteilen galten getrocknete Fleischprodukte als Nahrungsmittel, die sich auf die menschliche Gesundheit ungünstig auswirken, weil sie zur Entstehung von Arteriosklerose und hohem Blutdruck beitragen. Trockenschinken und lufgetrocknete Rohschinken sind aber Lebensmittel tierischen Ursprungs, die reich an Nährstoffen sind. Sie stellen eine wertvolle Quelle von Proteinen und Fetten dar, die infolge der Wirkung von endogenen Proteasen und Lipasen teilweise abgebaut werden. Sie stellen eine besonders wertvolle Quelle von freien Aminosäuren (essentiellen und nicht essentiellen) und Fettsäuren dar. Die Zusammensetzung der freien Aminosäuren hängt vom Genotyp der Schweine ab (enzymatische Muskelzusammensetzung), der Technologie der Verarbeitung und der Dauer der Reifung von Trockenschinken und luftgetrockneten Rohschinken. Die Zusammensetzung der freien Fettsäuren hängt größtenteils von der Fütterung der Schweine (Futterzusammensetzung), dem Halterungssystem der Schweine (offen, geschlossen), aber auch vom Genotyp der Schweine ab. Das Verhältnis zwischen den mehrfach ungesättigten Fettsäuren (PUFA) und den gesättigten (SFA) Fettsäuren unterschreitet am häufigsten die empfohlenen Grenzwerte (0,4-1), während das Verhältnis zwischen dem Gesamtanteil von n-6 und n-3 Fettsäuren die empfohlenen Werte der WHO übersteigt (2003). Infolge des hohen Anteils an Speisesalz (Natrium) müssen Menschen, die an Herzgefäßkrankheiten und Bluthochdruck leiden, beim Verzehr von Trockenschinken und luftgetrocknetem Rohschinken aufmerksam sein. Trockenschinken und luftgetrocknete Rohschinken sind einer wertvolle Quelle von Mineralstoffen, in erster Linie von Zink, Eisen und Selen sowie von Vitaminen, insbesondere aus der B-Gruppe der Vitamine. Wegen des hohen Anteils an Nährstoffen in leicht verdaulicher und freier Form eignen sich Trockenschinken und luftgetrocknete Rohschinken in erster Linie für die Ernährung von Sportlern.

1 January 2017 in Meso
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ĐSĐuro Senčić
Đuro Senčić
DSDanijela Samac
Danijela Samac
Za ljudski organizam jaja sadrže sve potrebne hranjive tvari, ali u nedovoljnim količinama. Konzumna jaja su prirodno pakirana namirnica (konzerva), bogata rezervnim hranjivim tvarima, vrlo važna u ljudskoj prehrani. Sadrže sve za život potrebne hranjive tvari, a naročito su dobar izvor esencijalnih aminokiselina, esencijalnih masnih kiselina, vitamina topivih u mastima, vitamina B12 i kolina, lecitina, željeza, fosfora i drugog. Iako sadrže kolesterol, prema novijim istraživanjima za većinu ljudske populacije on nije uzrok hiperkolesterolemije i kardiovaskularnih bolesti. Zbog visoke nutritivne gustoće (odnosa energije i hranjivih tvari) naročito su pogodna za prehranu osjetljivih populacijskih skupina ljudi (djece, staraca, kroničnih bolesnika, trudnica).Ključne riječi

1 January 2017 in Meso
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ĐSĐuro Senčić
Đuro Senčić
DSDanijela Samac
Danijela Samac
Schweingenotypen für die produktion von traditionellen haltbaren Fleischprodukten Die primäre Bedeutung für die Qualität traditioneller Fleischprodukte liegt in der Wahl des Schweinegenotyps für die Produktion der Fleischrohstoffe. Nicht alle Schweinegenotypen sind für die Herstellung von Dauerfleischprodukten gleichermaßen geeignet. Die Wahl des Genotyps hängt auch vom System ab, wie das Schwein während der Mast gehalten wurde. Für die Schweinemast im offenen und halb offenen System sind weniger produktive und widerstandsfähigere Rassen geeignet, und für die Intensivmast im geschlossenen System sind Schweinegenotypen geeignet, die eine gute Qualität der Schweinehälften und des Fleisches bei höherem Körpergewicht ergeben. Die Wahl des Schweinegenotyps hat bedeutenden Einfluss auf die Produktivität der Schweine während der Mast (täglicher Zuwachs, Futterverwertung), auf die Qualität ihrer Rümpfe (Hälften) und mittelbar auch auf die Qualität der Dauerfleischprodukte.