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The encapsulation of proteins into core-shell structures is a widely utilised strategy for controlling protein stability, delivery and release. Despite the recognised utility of these microstructures, however, core-shell fabrication routes are often too costly or poorly scalable to allow for industrial translation. Furthermore, many scalable routes rely upon emulsion-techniques implicating denaturing or environmentally harmful organic solvents. Herein, we investigate core-shell protein encapsulation through single-feed, aqueous spray drying: a cheap, industrially ubiquitous particle-formation technology in the absence of organic solvents. We show that an excipient’s preference for the surface of the spray dried particle is well-predicted by its hydrodynamic diameter (Dh) under relevant feed buffer conditions (pH and ionic strength) and that the predictive power of Dh is improved when measured at the spray dryer outlet temperature compared to room temperature (R2 = 0.64 vs. 0.59). Lastly, we leverage these findings to propose an adaptable design framework for fabricating core-shell protein encapsulates by single-feed aqueous spray drying.

Onions (Allium cepa L.) are one of the most harvested fresh vegetables in the EU, with annual production of residues amounting to about 0.5 M tonnes. Onion skin is rich in flavonoids, especially quercetin, but this biomass is usually discarded during processing. These bioactive compounds could be useful for a protective nutrition or as a technical ingredient in food products. This research examined the stability and degradation of free quercetin, green solvents and procedures for the extraction of quercetin from onion peel, as well as stabilisation through liposomal encapsulation. Initial stability of quercetin was examined by UV-Vis spectrometry and antioxidant capacity determination (pH from 2 to 8, temperatures from 25 to 90 °C, exposure time up to 24 hours). At ambient conditions and pH 2 in the dark, the levels of quercetin were relatively well maintained in the initial hours of observation, and markedly depleted after 24 h. Higher pH values (> 7.4) and/or light at higher temperatures (> 60 °C) further accelerated the depletion profiles. Further metabolomic screening showed additional information regarding metabolite formation. Ethanol (70 %) extracts of onion peel were used in further examination and quercetin was monitored by HPLC-PDA. Either quercetin standard or onion peel extract were entrapped in liposomes, at different ratios between the standard/extract and liposomes (1:20 and 1:100). The greatest encapsulation efficienty was observed for quercetin standard prepared with liposomes in ratio 1:20 (roughly 90%), while encapsulation efficiency of quercetin from onion peel extract, was lower (roughly 75%) at the same conditions. The stability of encapsulated quercetin was followed for 30 days using HPLC- PDA. Over 80 % stabilisation of quercetin in yellow onion skin was achieved with liposomal preparation. Furthermoer, the interactions between quercetin and lipids were characterised by differential scanning calorimetry, indicating that quercetin interacted mainly with the polar headgroup regions of the liposomal bilayer. Onion peel thus presents a rich source of quercetin which could be employed in the formation of stable functional dosage forms. Liposomal encapsulation offers an approach to overcome quercetin degradation.

Due to the high lignocellulose content, as well as the high content of phenolic compounds, agro-industrial vegetable waste is well suited for valorization in packaging materials. As specialized packing materials, these materials may offer competitive advantages to paper producers, utilizing a low cost feedstock to produce a bespoke product of good quality. In our contribution, we focus on the production residues of various plant streams (e.g. growing and processing of onions, olives and pomegranates), to demonstrate how such diverse agro-industrial bio-waste materials could be fully exploited even before their reformulation. Onion skins and olive leaves both showed high antioxidant activity and the possibility to recover relatively high yields of bioactive compounds (roughly 100 mg of quercetin or oleuropein per g of dry extract). However, in pomegranate peel, the content of the antocyanins (roughly 0.3 mg of antocyanins per g of dry extract) was low. All three plant residues sources produced unique paper materials. Olive skins and olive leaves were used as two individual feedstocks, whereas the pomegranate peel was required to be added to cellulose. The resulting papers exhibited good technological properties, as well as interesting texture and appearance and might as such be suited for the production of special papers. The determined characteristics of the samples demonstrate a good potential for cascading use where paper production should be further studied following the extraction of bioactive components.

In order to improve the knowledge on environmental impacts of current production systems and to find the solutions to reduce the negative impacts effective multi-approach environmental assessment methodologies are required. The environmental impacts assessed in complex systems, such as agriculture and food production, are prone to higher uncertainties. Therefore, field-specific standardization of the assessment procedures based on multiple screening studies are required to make the assessment outcome less vulnerable. The procedure array pairing for the formation of production step emission inventory is an important methodological process in environmental impact assessment. Initial production data was coupled with specialized databases, models found in scientific literature and environmental category characterization guidelines in order to construct an environmental impact methodological framework specific to four case studies of traditional food production. Analiza okoljskih vplivov dejavnosti agroživilskega sektorja je večplastno opravilo, ki nas pogosto privede do precej negotovih ocen. Oceno vpliva na okolje, v kateri hkrati obravnavamo več vidikov obremenjevanja okolja, lahko izboljšamo s področno-specifično standardizacijo postopkov presoje, ki temeljina podlagi konkretnih primerov iy proiyvodnje. Oblikovanje nabora postopkov za pripravo emisijske evidence posameynih proizvodnih korakov je pomemben proces ocenjevanja vplivov na okolje. V našem delu smo eksperimentalne in proizvodne podatke podprli s specializiranimi zbirkami podatkov, modeli iz strokovne literature ter smernicami za karakterizacijo okoljskih kategorij. Predstavljen metodološki okvir smo oblikovali za oceno okoljskega vpliva štirih primerov iz proizvodnje tradicionalnih živil.

In Slovenia we are facing with municipal waste problems, because their treatment is one of the worst solved goals in environmental protection. Landfilling is the most frequently used practise at the moment, which causes releasing of methane gas into the atmosphere. That's why better solutions are needed. In the present study we determined the potential methane production from organic municipal wastes of different particle size (particle size: >100 mm, 40-100 mm, 10-40 mm and 100 mm, 40-100 mm, 10-40 mm in

Z odpadno hrano se srečujejo vse izobraževalne institucije, ki jim ostanki hrane pomenijo tako finančno breme kot tudi možnost za izobraževanje na tem področju. V teoretičnem delu smo preučili problematiko odpadne hrane po svetu in Sloveniji ter organizacijo prehrane na različnih ravneh izobraževanja in ugotovili, da je smotrno prioritetno ukrepanje na nižjih ravneh izobraževanja. Na višjih nivojih izobraževanja se organizacija in strežba obrokov oddaljujeta od osrednje upravljavske ekipe izobraževalnega zavoda. Pregledali smo možne vzroke za kopičenje odpadne hrane in ukrepe za preprečevanje nastanka odpadne hrane ter ugotovili, da na količino odpadne hrane vplivajo število neprevzetih obrokov, prevelike količine skuhane hrane, prevelike porcije, nepravilno shranjevanje živil ter prehranske preference. Za preprečevanje kopičenja presežkov hrane lahko izobraževalne institucije uvajajo fleksibilne porcije, vključujejo učence v proces oblikovanja jedilnikov, izobražujejo na področju presežne in odpadne hrane, izvajajo preglede stanja, postavijo dodatne zahteve za ponudnike ali zamenjajo ponudnika v javnem razpisu, končni ukrep pri ravnanju z neizogibno količino odpadne hrane pa je lahko šolski kompost ali vrt. Ugotovili smo tudi, da vrtci in osnovne šole že izvajajo več projektov kot srednje šole in visokošolski zavodi. V empiričnem delu smo preverjali razlike v vzrokih za nastanek odpadne hrane med izobraževalnimi institucijami in ugotovili, da srednje šole neprevzete obroke pogosteje dojemajo kot pomemben vzrok za kopičenje presežkov hrane kot ostale izobraževalne institucije. V osnovnih in srednjih šolah so bili neprevzeti obroki označeni kot najpomembnejši vzrok, medtem ko je bil v vrtcih ta večinoma neatraktivnost obroka, med ponudniki v visokošolskih zavodih pa nepravilno shranjevanje živil. Poizvedeli smo o možnostih uvajanja različnih ukrepov ter ugotovili, da se izobraževalne institucije najpogosteje poslužujejo fleksibilnih porcij. Ta ukrep zlasti izvaja največ osnovnih šol, medtem ko vsi vrtci kot ukrep uvajajo spodbujanje otrok k jedi. Srednje šole so označile, da presežke hrane večinoma ponudijo dijakom za domov, medtem ko so zaposleni v visokošolskih zavodih in ponudniki organizirane prehrane največkrat navedli, da za študente izobešajo plakate na temo odpadne hrane. Ker je doniranje presežkov hrane lahko učinkovit neposreden način zmanjševanja presežkov hrane in posledično povzročanja odpadne hrane, nas je v raziskavi zanimalo, kako pogosto izobraževalne institucije donirajo presežno hrano. Ugotovili smo, da se doniranje redko izvaja. Vrtci, osnovne šole in srednje šole so kot najpogostejši zadržek za doniranje presežkov navedle varnost živil in s tem povezano odgovornost v postopku donacije, medtem ko za visokošolske zavode največji zadržek predstavljata logistika in organizacija doniranja. All educational institutions are confronted with the issue of food waste, that is simultaneously representing both a financial burden and an opportunity for education in this field. In the theoretical part, we examined the problem of food waste worldwide and in Slovenia, as well as the organisation of meals at different levels of education. We identified the need to take priority action in lower of education. At higher levels of education, the organization and serving of meals is detached from the management team at the educational institution. Further, we examined possible causes of food waste accumulation and measures to prevent food waste and conclude that the number of unclaimed meals, too much food cooked in advance, overportioning of meals, improper storage of food and dietary preferences (including the appearance and attractiveness of food) all have an impact on the amount of food waste. In order to prevent the accumulation of surplus food, educational institutions can introduce flexible portions, involve students in the menu design process and testing new menus, educate on surplus food and food waste, through the implementation of a diary forms, additional requirements for providers and through the educational opportunities of school gardens and composting unavoidable inedible food waste. In this respect, we have also found that kindergartens and primary schools are already implementing more projects than secondary schools and higher education institutions. In the empirical part, we examined differences in the causes of food waste between educational institutions and found that secondary schools are more likely to perceive unclaimed meals as an important cause of food surplus accumulation compared to other educational institutions. In elementary and intermediate schools, unclaimed meals were identified as the most important cause. Kindergartens however, identified the attractiveness/appearance of the meal so the most important factor. Furthermore, among the organised meal providers in higher education institutions, improper storage of ingredients was emphasized. We further queried the existing possibilities and measures for surplus food and food waste reduction, where offering flexible portions are most commonly used in educational institutions. In particular, most elementary schools are implementing this measure, while all kindergartens actively encourage children to eat. Intermediate schools indicated that they often offer surplus food to students to take home, while employees of higher education institutions and organised meal providers most frequently indicated that they put up food waste educational posters aimed to students. As donations of surplus food can be an effective direct way to reduce food surpluses and consequently food waste, our survey also inquired as to how often educational institutions donate surplus food. Respondents indicate that food surplus donation is rarely done. Kindergartens, primary schools and secondary schools referred to food safety and the corresponding liability in the process as the most common cause of reluctance to donate, while for higher education institutions the logistics and organisation of the donation were the cause of the most common reluctance.

Količine odpadne hrane in presežkov hrane so vezane na posamezen člen verige preskrbe s hrano (pridelava in predelava, prodaja, priprava) in predstavljajo stroškovni, družbeni ter okoljski problem. Diplomsko delo ponuja definicije ključnih besed, pregled statističnih podatkov, nacionalnih strategij in projektnih aktivnosti, ki spodbujajo pri preprečevanju in zmanjševanju nastanka presežkov hrane in odpadne hrane. Predstavljena je tudi metodologija zbiranja podatkov o odpadni hrani. Ker je poznavanje vzrokov za nastanek presežkov hrane in odpadne hrane na strani potrošnika relativno dobro poznano, se osredotočimo na njihovo nastajanje v drugih delih verige preskrbe s hrano, kjer je poznavanje vzrokov slabše. Doniranje hrane je učinkovit vzvod za zmanjševanje količin presežne hrane, je pa potrebno raziskati še druge možnosti kako uporabiti presežke hrane in s tem zmanjšati količine odpadne hrane, ki z vsakim letom še vedno naraščajo. The quantities of food waste and food surplus are linked to individual link in food supply chain (production, processing, wholesale and retail and preparation) and they cause financial, social and enviromental consequences. In the thesis, we provide definitions of key terms linked to food waste, an overview of statistical data, as well as national strategies and project activities which encourages prevention and reduction of food surpluses and food waste. The methodology of data collection on food waste is also presented. The causes of food surplus and food waste are relatively well known on the consumers part, but not as well in other phases of the food supply chain. For that reason the emphasis is on phases before consumers. Food donation is an effective way to reduce food surpluses but also other solutions for food surplus redistribution and food waste reduction are required, because the owerall wasted amounts are still increasing on a yearly basis.

V živilskem sektorju ima 3D tiskanje veliko uporabno vrednost. Omogoča tiskanje prilagojenih oblik in modelov, pripomore k personalizirani prehrani, omogoča uporabo prehranskih dopolnil proizvedenih iz odpadne hrane in odvečnih tokov živilske industrije. Rastlinski odpadki so lahko vir dragocenih snovi. Netoksične naravne spojine z antioksidativnim delovanjem v odpadni hrani so pritegnile veliko pozornost, saj je vse bolj jasna neposredna povezava med prehrano, bogato z antioksidanti, in zdravjem. V eksperimentalnem delu naloge smo ugotavljali, kako dodatek čebulnega prahu in spiruline (kot naravnih antioksidantov) v 3D tiskanem živilu vpliva na vsebnost vlage, teksturo, parametre barve in senzorične lastnosti po pripravi in med shranjevanjem piškotov. Rezultati so pokazali, da smo v primeru dodatkov dobili boljše lastnosti končnega izdelka (razen pri senzorični oceni). Z meritvami nismo uspeli potrditi, da dodatek funkcionalnega živila z antioksidativnim učinkom pozitivno vpliva na obstojnost živila. Ob dodatku funkcionalnega živila so se senzorične lastnosti spremenile. Bistveno se je spremenila barva, na druge senzorične lastnosti pa je imela večji vpliv vrsta moke, kot pa sam funkcionalni dodatek. In food sector 3d printing has a big usable value. It enables the printing of customized shapes and models, contributes to a personalised diet, enables the use of food supplements from food waste and excess streams of the food industry. Plant waste can be a source of valuable substances. Non-toxic natural compounds with antioxidant activity in food waste have attracted a lot of attention as there is an increasingly clear direct link between a diet rich in antioxidants and health.. During the experimental work we found out how the addition of onion powder and spiruline (as natural antioxidants) to a 3D printed food affects moisture content, texture, color parameters and sensory properties after preparation and during biscuit storage. The results showed that in the case of added additives, we got better properties of the finished product (except for sensory evaluation). We were unable to confirm by measurements that the addition of a functional food with an antioxidant effect has a positive effect on the persistence of the food. With the addition of a functional food, the sensory properties changed. The colour changed significantly, and other sensory properties had a greater impact on the type of flour than the functional additive itself.