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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

The effect of oven and microwave drying methods on the drying kinetics and physical properties of two banana vatieties in Limpopo Province, South Africa

Omolola, Adewale Olesegun 02 February 2016 (has links)
PhD (Agric) / Department of Food Science
62

Оценка эффективности проекта радиационной обработки продукции агропромышленных предприятий : магистерская диссертация / Evaluation of the effectiveness of the project of radiation treatment of agricultural products

Вазиров, Р. А., Vazirov, R. A. January 2021 (has links)
Современные агропромышленные предприятия терпят значительные убытки, связанные с потерей от 10 до 30% продукции от микробиологического загрязнения. Производители сельскохозяйственной и пищевой продукции, стремящиеся к увеличению сроков хранения, а также биологической безопасности продукции, внедряют новые методы их обработки. На сегодняшний день широкую популярность в мире набирает методы радиационной обработки с применением различных видов ионизирующего излучения. Цель работы – провести оценку эффективности проекта радиационной обработки продукции агропромышленных предприятий. Научная новизна состоит в применение традиционных методов оценки эффективности к новому методу радиационной обработки продукции, внедряемого в технологические процессы агропромышленных комплексов Свердловской области. Практическая значимость заключается в комплексной оценке экономической эффективности проекта создания Центра радиационной обработки продукции агропромышленных предприятий с учетом различных уровней загрузки оборудования. / Modern agro-industrial enterprises suffer significant losses associated with the loss of 10 to 30% of products due to microbiological contamination. Manufacturers of agricultural and food products, seeking to increase the shelf life, as well as the biological safety of products, are introducing new methods of its processing. To date, methods of radiation treatment with the use of various types of ionizing radiation are gaining wide popularity in the world. The purpose of the work is to evaluate the effectiveness of the project of radiation treatment of agricultural products. The scientific novelty consists in the application of traditional methods of efficiency assessment to a new method of radiation treatment of products introduced into the technological processes of agro-industrial complexes of the Sverdlovsk region. The practical significance lies in a comprehensive assessment of the economic efficiency of the project to create a Center for radiation treatment of agricultural products, taking into account different levels of equipment loading.
63

Konsumentens gröna livsmedelskompass

Schunnesson Flores da Cunha, Luiza January 2017 (has links)
This study aimed to get a better understanding for how packaging design, brand and certifications guide Swedish consumers when choosing between different ecological food products. The study further investigated how brands could use packaging design and a certification strategy as a way to advertising the brand and the food as ecological. By using both quantitative and qualitative methods in form of online survey and two semi-structured interviews, the study got a two-sided perspective on the subject. The results from the online survey collected answers from 100 Swedish respondents during a time period of two weeks. By comparing the packaging design of brands selling only ecological food products and brands selling both ecological and non-ecological food products, the later one more often used typical ecological design element on their packaging. From the survey a conclusion was made that there were a difference between what kind of information consumers wanted and what was important for them when choosing ecological food. Both certification and the word ecological on the package were listed highest regarding what was of most importance when choosing ecological food products and close thereafter was the brand listed. Nearly the same results was given regarding what information was of most importance, but here the brand came after factors such as origin and list of contents. Despite that, packaging design, certification strategy, and brand is still of outermost relevance for Swedish consumers when buying ecological food products. / Studien syftade till ökad förståelse för hur förpackningsdesign, varumärken och certifieringar vägleder svenska konsumenter när de väljer ekologiska och miljövänliga livsmedel. Vidare undersöktes hur varumärken skulle kunna använda förpackningsdesign och certifierings-strategier för att marknadsföra sina livsmedel som ekologiska. Genom att använda såväl kvantitativa och kvalitativa metoder i form av webbundersökning och två semistrukturerade intervjuer, gavs ett tvåsidigt perspektiv i ämnet. Webbundersökningen samlade in svar från 100 svenska respondenter under en två veckors period. Genom att därefter jämföra förpackningens design hos varumärken med hel-ekologiskt sortiment och varumärken med ekologiska alternativ, visade det sig att de senare oftare använde typiska ekologiska designelement på förpackningsdesignen. Från webbundersökningen upptäcktes det att konsumenter efterfrågade olika saker när det gällde att få information jämfört med vad som var viktigt vid val gällande ekologiska livsmedel. Både certifieringar och ordet ekologiskt på förpackningen var högst rankat som faktorer över vad som viktigt för konsumenterna. På denna lista placerades varumärket kort därefter. Liknande resultat gavs för vilken information som var viktigast, dock kom både ursprungsland och innehållsförteckning före varumärke. Trots rankingen så tycks fortfarande förpackningsdesign, certifieringsstrategi och varumärket vara av högsta relevans för svenska konsumenter vid köp av ekologiska livsmedel.
64

Do geographical indications promote sustainable rural development? : two UK case studies and implications for New Zealand rural development policy

Williams, Rachael M. January 2007 (has links)
Geographical indications (GIs) are one form of protective labelling used to indicate the origin of food and alcohol products. The role of protected geographical indicators as a promising sustainable rural development tool is the basis for this research. The protection of geographical indications is a rather controversial subject and much research is still required for both sides of the debate. The research method employed for this study is qualitative critical social science. Two Case studies are used to investigate the benefits brought to rural areas through the protection of GIs. The case studies include the GIs Jersey Royal and Welsh Lamb both from the United Kingdom a member of the European Union (the EU is in favour of extended protection of GIs for all agro-food products under the 1994 WTO/TRIPS agreement on geographical indications). Twenty-five indepth interviews were conducted for this study the duration of the interviews was approximately one hour. The study identifies predominantly indirect links between GIs and sustainable rural development, through economic and social benefits bought to rural areas by the GIs investigated - less of a connection was found to ecological elements. No considerable cost for GI protection was discovered. This finding suggests that GIs are worthwhile for implementation in New Zealand as a rural development tool.
65

I consumatori di fronte ai paradossi dell’offerta di prodotti alimentari sostenibili. Uno studio comparativo tra Francia e Italia / LES CONSOMMATEURS FACE AUX PARADOXES DE L'OFFRE DE PRODUITS ALIMENTAIRES DURABLES. Une étude comparative entre France etItalie / Consumers faced with the paradoxes of sustainable food products offer. A comparative study between France and Italy

MORUZZI, ROMINA 21 February 2013 (has links)
Questo studio si propone di esplorare i paradossi esistenti nell’offerta di prodotti alimentari sostenibili e, di conseguenza, i comportamenti (strategie di coping) (Lazarus e Folkman, 1984) adottati dai consumatori al momento di tale percezione. A questo scopo abbiamo adattato il modello concettuale di Mick e Fournier (1998), sviluppato inizialmente per i paradossi delle tecnologie moderne, al contesto dell’Alimentazione sostenibile. A livello metodologico, è stata realizzata un’inchiesta qualitativa presso 84 individui “ordinari” (non militanti) in Francia e Italia. In più, sono stati interrogati 18 soggetti (individui militanti) che fanno abitualmente i loro acquisti presso la rete dell’AMAP, in Francia, e dei GAS in Italia. Le interviste semi-strutturate hanno permesso di mettere in luce delle differenze tra i consumatori “ordinari” dei due Paesi da un punto di vista delle strategie di coping evocate per superare i paradossi percepiti. Così abbiamo proposto tre profili di consumatori “ordinari”. Al contrario gli individui militanti si avverano come un gruppo più omogeneo tra i due contesti d’indagine, sia a livello di percezione di paradossi sia nell’adozione di pratiche sostenibili. La ricerca ha, altresì, evidenziato delle caratteristiche più specifiche alle due nazioni, per esempio a livello della struttura di mercato, della comunicazione sui prodotti sostenibili, nonché nell’ottica delle caratteristiche socioculturali. Pertanto questo studio ha avuto tre obiettivi: teorico al fine di verificare i paradossi elencati e le strategie di coping adottate dai consumatori francesi e italiani; metodologico adattando gli “ingranaggi” del modello concettuale di Mick e Fournier (1998) al contesto specifico di ricerca; e poi pratici allo scopo di distinguere degli elementi frenanti la diffusione dell’offerta sostenibile e altri che possano favorire lo sviluppo di un consumo sostenibile in ciascun Paese, come attraverso un’offerta più mirata agli aspetti ambientali in Francia ("filière nord/nord" di agricoltori francesi equo-solidali, biologici e locali) e delle produzioni più legate agli aspetti etici in Italia (ex. prodotti di economie solidali). / This study aims to explore existing paradoxes in the offer of food sustainable products and consequently consumers’ behaviours (coping strategies) (Lazarus and Folkman, 1984) at the time of this perception. For this purpose, the theoretical model of Mick and Fournier (1998), built initially for studying the paradoxes of modern technologies, were adapted to sustainable food consumption. At methodological level, a qualitative survey was conducted among 84 “ordinary” consumers in France and Italy. Later other 18 subjects, usually involved into sustainable purchases (participants of AMAP, GAS), were interviewed. The semi-structured interviews shed light on some differences between “ordinary” consumers of the two countries when they adopted coping strategies to go beyond perceived paradoxes. Thus we proposed three ordinary consumers’ profiles. On the contrary engaged individuals are like a more homogeny group going over national boundaries. They agree with paradoxes and sustainable practices. In addition, the research pointed out some divergent aspects connected with specific context, for instance market of sustainable food products, communication over this offer and social cultural characteristics. Finally, this work had three objectives: theoretical to verify the paradoxes listed and evocated consumers’ strategies by French and Italian consumers; methodological regarding the adaptation of the conceptual model “gears” of Mick et Fournier (1998) to the context of sustainable consumption; and then practical ones such as identification of barriers for developing sustainable consumption and specific possible ways of growth: more attention to environmental aspects in France (“filière nord/nord” of organic, fairly, local French peasants) and ethics products in Italy (products issued from social economies).
66

Exploring consumers’ procedural knowledge and perception of genetically modified (GM) food products and the factors that influence their purchasing decision

Van Zuydam, Sone Corne 01 1900 (has links)
Abstracts in English, Xhosa and Zulu / This quantitative study explores procedural knowledge, perception of GM food products and factors that influence the purchasing decision of 326 respondents by means of a questionnaire. Recruitment of the respondents was done by approaching various businesses and Schools in Mooi River to which the questionnaire was distributed to their respective personnel. The respondents’ showed that they were not very knowledgeable of GM food products, but were not particularly ignorant either. The results also showed that they did not look for any GM-related information from various sources and believed that scientists were the most credible source of GM-related information. In general, the respondents did not perceive GM food products as having any nutritional benefits; did not perceive GM food products to provide an economic benefit, except to increase food supplies by boosting the economy through the implementation of biotechnology; and perceived longer shelf life as a beneficial GM food product quality. The respondents also feared the susceptibility to cancer, toxicity, allergic reactions, alterations in kidney functions, immune malfunction and especially infertility problems after consumption of GM food products. The respondents did not show particular fear towards the ethical aspects of GM food products, except in that GM food products are produced in an unethical manner. Fear was also not shown towards the consumption aspects of GM food products including scepticism towards the safety GM food products and possible threats to living things. The respondents indicated that increased food supplies through the production of GM food products, possible cancer development after consumption, allergenicity, reduced usage of pesticides and harmful effect on the environment were GM-related factors that would influence their purchasing decision of GM food products. The general GM-related barriers that influenced the respondents purchasing decision of GM food products included not looking out for GM food products in particular, knowing too little about GM food products, not having a particular interest in GM food products and never knowing if a product contains a GM component or not. / Esi sifundo, nesiqhutywa ngokuqwalasela amanani ezenzeko, saphanda ngolwazi lwendlela ebonwa ngayo inkqubo yeemveliso zokutya zeGM (iimveliso ezinyangwe ngobuchule obaziwa ngelesiNgesi elithi genetically modified) kwakunye neemeko eziphembelela izigqibo zokuthenga ezi mveliso, zigqibo ezo zathathwa ngabathathi nxaxheba abangama-326 nabathi baphendula uluhlu lwemibuzo. Ukuloba/ukurhwebesha abathathi nxaxheba kwenziwa ngokucela uncedo kumashishini nezikolo eziseMooi River. Abathathi nxaxheba baveza ukuba abanalwazi kakuhle ngeemveliso zokutya zeGM, kodwa banalo ufifana. Iziphumo zadiza ukuba azange baphande ulwazi olumalunga nonyango lweemveliso kwaye babekholelwa ukuba iingcali zenzululwazi zizo ezaziyimithombo yolwazi ethembekileyo malunga nalo mbandela. Ngokuthe gabalala, abathathi nxaxheba babengaziboni ziluncedo kwisondlo okanye kuqoqosho ezi mveliso zokutya zeGM, kwaye babelindele ukuba ezi mveliso zandise ukutya okuveliswayo ngokukhuthaza ezoqoqosho ngokusebenzisa ubuchwepheshe bezendalo, (ibiotechnology). Babecinga ukuba uphawu oluluncedo lokutya okuveliswe ngeendlela zeGM kukuba kuhlala ixesha elide, akonakali msinya. Abathathi nxaxheba babesoyika ukuba bangasifumana lula isifo somhlaza, bangafumana ukutyhefeka kokutya, ukusoleka (iallergy), ukuchaphazeleka kokusebenza kwezintso, ubuthathaka bamajoni omzimba, okanye ubuthathaka benzala emva kokutya iimveliso zokutya zeGM. Abazange babonakalise uloyiko olumandla malunga nombandela weenqobo zesimilo ezayanyaniswa neemveliso zokutya zeGM, ngaphandle kokuba ezi mveliso ziveliswa ngendlela engenasimilo sisulungekileyo. Kwakhona, abazange babonakalise loyiko malunga nokutya iimveliso zokutya zeGM, bengazange bakrokrele ukungakhuseleki kwezi mveliso okanye ukuba yingozi kwazo kwezinye izidalwa. Abathathi nxaxheba baxela ukuba izigqibo zabo zokuthenga iimveliso zokutya zeGM zingaphenjelelwa kukucinga ngokwanda kokutya okuveliswayo, ukuvela komhlaza emva kokuzitya, ukusolwa, ukucutha ukusebenzisa izibulali zinambuzane kunye neziphumo ezinobungozi kwindalo esingqongileyo. Imiqobo jikelele engqamene nonyango lweGM neyaphembelela izigqibo zabathathi nxaxheba malunga nokuthenga iimveliso zokutya zeGM ziquka ukwazi kancinci ngeemveliso zokutya zeGM, kukungabi namdla kwiimveliso zokutya zeGM nokuba ubani angabi nalwazi lokuba imveliso ethile inalo na unyango lweGM okanye ayinalo. / Lolu cwaningo olugxile kwinani luye lwaphenya ulwazi olumayelana nolwazi lwengqubo, umqondo omayelana nenhlobo yokudla okuguquliwe (GM food) kanye nezinto ezinomthelela phezu kwesinqumo sokuthenga sabaphenduli bemibuzo abanga-326, lokhu kwenziwe ngokusebenzisa umbhalo oqukethe imibuzo. Abaphenduli bemibuzo batholwe ngokunxenxa amabhizinisi kanye nezikole ezihlukahlukene endaweni yaseMooi River. Abaphenduli bemibuzo bakhombisile ukuthi babenganalwazi ngemikhiqizo yokudla eguquliwe (GM), kanti laba baphenduli abazange bakhombise ukungabambisani nalolu cwaningo. Imiphumela iyakhombisa ukuthi abaphenduli abazange bafune ukuthola noma yiluphi ulwazi olumayelana Nokudla kwe-GM kwimithombo eyahlukahlukene kanti baye bakholwa ukuthi ososayensi bayimithombo yolwazi ethembekayo. Empeleni, abaphenduli abazange baqonde imikhiqizo yokudla kwe-GM njengokudla okunenzuzo yomsoco noma inzuzo yezomnotho kanti bebelidele le mikhiqizo ukuba yongeze inani lokudla elithunyelwayo ngokuxhasa umnotho ngokusebenzisa uhlelo lwe--biotechnology. Bakholelwa ekutheni umkhiqizo uhlale isikhathi eside emasheluvini, lokho okuyinzuzo kwikhwalithi yemikhiqizo yokudla kwe-GM. Abaphenduli baye besaba ukungenwa yisifo somdlavuza, ushevu, ukuguliswa yinhlobo yokudla okuthile, ukushintshana kokusebenza kwezinso, ukungasebenzi kahle kwamasosha omzimba kanti ikakhulu izinkinga zokwehluleka ukuzala ngemuva kokudla imikhiqizo yokudla kwe-GM. Abaphenduli abazange bakhombise ukwesaba mayelana nokuziphatha kwimikhiqizo yokudla kwe-GM, ngaphandle kokuthi nje le mikhiqizo ikhiqizwa ngendlela ephambene nomthetho. Abaphenduli abazange futhi bakhombise ukwesaba mayelana nodaba lokudliwa komkhiqizo wokudla kwe-GM,kuxutshwa phakathi ukuthandabuza mayelana nokuphepha kwale mikhiqizo kanye nalokho okungahle kuphazamise izinto eziphilayo. Abaphenduli baye bakhombisa ukuthi imizamo yokuthi kube nokudla okuningi ngokukhiqiza imikhiqizo yokudla kwe-GM, amathuba wokuphathwa yisifo somdlavuza ngemuva kokudla lokho kudla, ukungathandwa wukudla okuthize, ukunciphiswa kwezinga lokusebenziswa kwezibulalizinambuzane kanye nomphumela oyingozi phezu kwemvelo bekuyizinto ezihlobene nokudla kwe-GM lokho okuzoshintsha indlea yabo yokuthenga imikhiqizo yokudla kwe-GM. Izihibhe ezejwayelekile ezihlobene ne-GM eziye zashintsha isinqumo sabaphenduli sokuthenga imikhiqizo yokudla kwe-GM bekuxuba phakathi ukuphuma bayofuna ikakhulu imikhiqizo yokudla kwe-GM, luncane kakhulu ulwazi abanalo ngemikhiqizo yokudla kwe-GM, kuxuba ukungathandi imikhiqizo yokudla kwe-GM kanye nokungazi ukuba ngabe umkhiqizo wequkethe umkhakha we-GM noma akunjalo. / Life and Consumer Sciences / M.A. (Consumer Science)
67

Microalgae as novel ingredients for the formulation of food products

Uribe Wandurraga, Zaida Natalia 10 January 2021 (has links)
[ES] Las microalgas son organismos unicelulares fotosintéticos microscópicos que se encuentran en gran variedad de ambientes y son muy eficientes en la transformación de energía solar en biomasa. Los estudios realizados hasta el momento hacen referencia a posibles beneficios de la incorporación de microalgas en la dieta, por la mejora del sistema cardiovascular, las propiedades adelgazantes y energizantes, capacidad antioxidante, o la reducción del colesterol y los triglicéridos. La forma más habitual de consumir las microalgas es como suplemento dietético en forma de tabletas, cápsulas o polvo. La incorporación de biomasa de microalgas en productos tradicionales se ha enfrentado al reto de la aparición de colores verdes fuertes, así como su consistencia pulverulenta que puede afectar la textura y percepción del producto. Todos estos aspectos constituyen las principales áreas de mejora para conseguir un mayor grado de aceptación de productos con microalgas, y son la base del reto de este proyecto. El objetivo de la presente tesis doctoral fue el desarrollo de nuevos productos alimentarios incorporando las propiedades nutricionales de la biomasa de microalgas, incrementando o mejorando con ello, las propiedades nutricionales del alimento original. Para conseguir este objetivo se evaluaron a nivel fisicoquímico, reológico y textural, la incorporación de diferentes especies de microalgas (Arthrospira platensis (Spirulina), Chlorella vulgaris, Dunaliella salina y Nannochloropsis gaditana) en distintas matrices alimentarias (productos horneados, emulsiones y extrusionados). Por otra parte, se evaluó y caracterizó la incorporación de las microalgas utilizando diferentes tecnologías como la impresión 3D o la extrusión. Además de cómo afecta la incorporación de las microalgas a los productos obtenidos, se evaluaron los aspectos nutricionales de su incorporación, en cuanto al aporte de minerales y su biodisponibilidad. Las propiedades reológicas de las masas y emulsiones enriquecidas con microalgas (Spirulina, Chlorella y Dunaliella) indicaron que su comportamiento viscoelástico fue modificado y mejorado, mostrando características aptas para este tipo de productos. La adición de microalgas (Spirulina y Chlorella) a las masas utilizadas para la impresión 3D de galletas y snacks, permitió una mejor extrusión o impresión de éstas, obteniendo muestras impresas en 3D de forma cilíndrica, más precisas en cuanto a sus dimensiones con respecto a la estructura cilíndrica diseñada. Además, las muestras impresas presentaron mayor estabilidad y resistencia, antes y después del proceso de horneado comparadas con la muestra control. Para los productos horneados, tanto para las rosquilletas como los snacks impresos en 3D, la adición de microalgas (Spirulina y Chlorella) permitió mayor estabilidad en términos de textura. Ligeros cambios en los parámetros fisicoquímicos y de expansión se produjeron por la adición de Spirulina y Chlorella en los productos extrusionados. Además, los extrusionados enriquecidos con Nannochloropsis, mostraron parámetros similares a los de la muestra de control. Todos los productos presentaron colores luminosos y apariencias innovadoras y atractivas. En cuanto a los minerales, se observó un aumento de P, K, Ca, Na, Mg, Fe y Se con la adición de Spirulina y Chlorella, junto con el aumento de la concentración adicionada de microalgas. Siguiendo la normativa sobre etiquetado nutricional de los alimentos, el enriquecimiento con microalgas en rosquilletas se puede clasificar como un alimento "rico en hierro (Fe)". De igual forma, las rosquilletas y galletas enriquecidas con microalgas pueden considerarse un alimento "alto en selenio (Se)". Además, la incorporación de Spirulina y Chlorella en las formulaciones de galletas, permitió una mayor bioaccesibilidad del contenido de P, K, Ca, Mg, Fe, Zn y Se para la absorción en el cuerpo comparado con las muestras control. / [CAT] Les microalgues són organismes unicellulars fotosintètics microscòpics. Són molt eficients a l'hora de transformar l'energia solar en biomassa. Els estudis realitzats fins ara fan referència a possibles beneficis de la incorporació de microalgues en la dieta per produir una millora del sistema cardiovascular, per presentar propietats per aprimar i donar energia, per mostrar capacitat antioxidant o per afavorir una reducció del colesterol i els triglicèrids. La forma més habitual de consumir microalgues és com a suplement dietètic en forma de tauleta, càpsula o en pols. La incorporació de biomassa de microalgues en productes tradicionals s'ha afrontat al repte de l'aparició d'un color verd fosc i d'una consistència polsosa que pot afectar a la textura i, per tant, a la percepció del producte. Aquests aspectes constituïxen les principals àrees de millora per aconseguir un major grau d'acceptació de productes amb microalgues i són la base del repte d'aquest projecte. L'objectiu d'aquesta tesi doctoral és el desenvolupament de nous productes alimentaris que incorporen les propietats nutricionals de la biomassa de microalgues, de manera que s'incrementen o es milloren les propietats nutricionals de l'aliment original. Per aconseguir aquest objectiu s'avaluaren a escala fisicoquímica, reològica i de textura la incorporació de diferents espècies de microalgues (Arthrospira platensis (Spirulina), Chlorella vulgaris, Dunaliella salina i Nannochloropsis gaditana) en diferents matrius alimentàries (productes fornejats, emulsions i extrudits). D'altra banda, s'avaluà i caracteritzà la incorporació de les microalgues utilitzant diferents tecnologies com la impressió en 3D o l'extrusió. A banda de valorar com afecta la incorporació de microalgues als productes elaborats, s'avaluaren els aspectes nutricionals, pel que fa a l'aportació i biodisponibilitat de minerals. Les propietats reològiques de les masses i emulsions enriquides amb microalgues (Spirulina, Chlorella i Dunaliella) indicaren que el seu comportament viscoelàstic fou modificat i millorat, de tal manera que mostrà característiques aptes per aquest tipus de productes. L'addició de microalgues (Spirulina i Chlorella) en les masses utilitzades per a la impressió 3D de galetes i snacks permeté una millor impressió, ja que s'obtingueren mostres impreses de forma cilíndrica amb unes dimensions més precises respecte a l'estructura cilíndrica dissenyada. A més, les mostres impreses presentaren una major estabilitat i resistència abans i després del procés de fornejat en comparació amb la mostra control. Respecte als productes fornejats, l'addició de microalgues (Spirulina i Chlorella) a les rosquilletes i els snacks impresos en 3D permeté una major estabilitat en termes de textura. Lleugers canvis als paràmetres fisicoquímics i d'expansió es produïren per l'addició d'Spirulina i Chlorella en els productes extrudits. A més, els extrudits que foren enriquits amb Nannochloropsis mostraren paràmetres similars als de la mostra control. Tots els productes presentaren colors lluminosos i aparences innovadores i atractives. Pel que fa als minerals, s'observà un augment de P, K, Ca, Na, Mg, Fe i Se quan s'afegí Spirulina i Chlorella, directament relacionat amb l'augment de la concentració de microalgues. Seguint la normativa sobre etiquetatge nutricional dels aliments, l'enriquiment amb microalgues en rosquilletes ens permet classificar-les com a aliment "ric en ferro (Fe)". De la mateixa manera, les rosquilletes i galetes enriquides amb microalgues poden considerar-se un aliment "alt en seleni (Se)". A més a més, la incorporació de Spirulina i Chlorella en les formulacions de galetes, permeté una major bioaccessibiltat del contingut de P, K, Ca, Mg, Fe, Zn i Se comparat amb les mostres control. / [EN] Microalgae are microscopic unicellular and photosynthetic organisms that can be found in a wide variety of environments. These microorganisms are very efficient when transforming solar energy into biomass, due to their cellular structure, which is completely submerged in an aqueous medium, forming an adequate surface for the exchange of nutrients and gases. Microalgae compounds are now known to exhibit cardioprotective, immunomodulatory, anti-proliferative, anti-inflammatory, cognitive, neurobehavioral and antimicrobial properties, amongst others. Researchers have shown possible benefits of the incorporation of microalgae in the diet so far. The most common way to consume microalgae is as a dietary supplement in the form of tablets, capsules or powder. The incorporation of microalgae biomass in traditional products has faced the challenge of the appearance of strong green colours, as well as its powdery consistency that can affect the texture and perception of the product. All these aspects constitute the main areas for improvement the development of microalgae-based products, and they are the challenges faced of this project. The main objective of this PhD Thesis was the development of novel food products incorporating the nutritional properties of microalgae biomass, thereby increasing or improving the nutritional properties of the original food matrix. To achieve this goal, the effect of the addition of different species of microalgae (Arthrospira platensis (Spirulina), Chlorella vulgaris, Dunaliella salina and Nannochloropsis gaditana) on the physicochemical, rheological and textural properties of different food matrices (baked products, emulsions and extrudates) was evaluated. Furthermore, the effect of the incorporation of microalgae using different technologies such as 3D printing or extrusion to obtain food products was studied. In addition, how the incorporation of microalgae affects the nutritional aspects of the food products in terms of the contribution of minerals and their bioavailability was also evaluated. The rheological properties of doughs, batters and emulsions enriched with microalgae (Spirulina, Chlorella and Dunaliella) indicated that their viscoelastic behaviour was modified and improved, showing characteristics suitable for this type of products. The addition of microalgae (Spirulina and Chlorella) to the doughs and batters used for the 3D printing of cookies and snacks, allowed a better extrusion or printing behaviour. This allowed obtaining cylindrical 3D printed samples, more precise in terms of their dimensions with respect to the designed cylindrical structure. In addition, the 3D microalgae-printed sample structures presented greater stability and resistance, before and after the baking process compared to the control sample. For baked products, both for breadsticks and 3D printed snacks, the addition of microalgae (Spirulina and Chlorella) allowed greater stability in terms of texture. Slight changes in the physicochemical and expansion parameters were produced by the addition of Spirulina and Chlorella in the extruded products. In addition, the extrudates enriched with Nannochloropsis, showed similar parameters to those of the control sample. Microalgae-enriched obtained products showed bright colours with appealing appearances. Regarding minerals, an increase in P, K, Ca, Na, Mg, Fe and Se was observed with the addition of Spirulina and Chlorella, along the increase of concentration of microalgae addition. Following the regulations on nutrition labelling for food stuffs, breadstick enrichment with microalgae are a food "high in iron (Fe)" In the same way, breadsticks and cookies enriched with microalgae can be considered a "high in selenium (Se)" food. Going a step further, Spirulina and Chlorella vulgaris incorporation in cookie formulations allowed for greater bioaccessibility of P, K, Ca, Mg, Fe, Zn, and Se content for absorption in the body than control cookies. / Uribe Wandurraga, ZN. (2020). Microalgae as novel ingredients for the formulation of food products [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/158743 / TESIS
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Hemijski sastav, biološke i funkcionalne karakteristike novih proizvoda od zove / Chemical composition, biological and functional characteristics of new elderberry products

Vujanović Milena 14 December 2020 (has links)
<p>Glavni cilj ove doktorske disertacije je određivanje hemijskog sastava, biolo&scaron;kih i funkcionalnih karakteristika novih proizvoda od zove. Dobijanje proizvoda na bazi zove zasniva se na primeni tradicionalnih i savremenih tehnolo&scaron;kih procesa proizvodnje. Iskori&scaron;ćenje prirodnog potencijala zove započeto je primenom tradicionalne i savremene (liofilizacija) tehnike su&scaron;enja. U cilju dobijanja visoko-vrednih ekstrakata ploda i cveta zove primenjene su tradicionalna (maceracija) i savremene (ultrazvučna i mikrotalasna) ekstrakcione tehnike sa dva ekstragensa (50% etanol i voda). Dobijanje matičnog soka od plodova zove podrazumevalo je primenu tradicionalnog načina ceđenja, dok je vino od plodova zove dobijeno po standardnom postupku proizvodnje vina. Vino je izloženo različitim temperaturnim tretmanima u različitom vremenskom periodu (60 &deg;C u toku 5 minuta, 60 &deg;C u toku 10 minuta, 70 &deg;C u toku 5 minuta i bez toplotnog tretmana) u cilju evaluacije biolo&scaron;ke aktivnosti dobijenog proizvoda. Etarsko ulje ploda i cveta zove je dobijeno hidrodestilacijom. Ispitivanje efikasnosti primenjenih tehnolo&scaron;kih postupaka su&scaron;enja i ekstrakcije je zasnovano na određivanju biolo&scaron;kih i funkcionalnih karakteristika dobijenih ekstrakata ploda i cveta zove. U ispitivanim ekstraktima ploda i cveta zove dominantne fenolne kiseline su hlorogenska i protokatehinska kiselina, a rutin i kvercetin-3-O-heksozid su dominantna flavonoidna jedinjenja. Biolo&scaron;ke i funkcionalne karakteristike su ispitane primenom različitih in vitro antioksidativnih, neuroprotektivnih, antitirozinaznih i antidijabetogenih testova. Primenom liofilizacije kao savremene tehnike su&scaron;enja i mikrotalasne ekstrakcije kao savremene ekstrakcione tehnike povećava se biopotencijal ispitivanih ekstrakata. Matični sok od plodova zove kao potencijalno novi funkcionalni proizvod je analiziran u cilju definisanja hemijskog, fitohemijskog i nutritivnog sastava, biolo&scaron;kog potencijala i senzorskih karakteristika. Ispitivanja dobijenog vina su bila usmerena na utvrđivanje optimalnih uslova za proizvodnju voćnog vina. Definisanjem hemijskog i fitohemijskog sastava i evaluacijom biopotencijala vina određen je optimalan temperaturni profil za dobijanje jednog od novih funkcionalnih proizvoda. Na osnovu utvrđenog hemijskog sastava etarsko ulje ploda i cveta zove se pokazalo kao potencijalno novi prirodni agens za održavanje svežine i produženja roka trajanja prehrambenih proizvoda. Zova je nesumnjivo samonikla biljna vrsta koja u budućnosti osnovano može biti polazna sirovina za kreiranje i dobijanje novih prehrmabenih proizvoda na domaćem i inostranom trži&scaron;tu.</p> / <p>The main goal of this doctoral dissertation is to determine the chemical composition, biological and functional characteristics of new elderberry products. Elderberry products were obtained via traditional and modern technological processes. The exploitation of the natural potential of the elderberry started with the application of traditional and modern (lyophilization) drying techniques. To obtain high-value extracts of fruits and flowers, traditional (maceration) and modern (ultrasonic and microwave) extraction techniques with two solvents (50% ethanol and water) were applied. Obtaining the juice from the elderberry fruits implied the application of the traditional cold pressing method, whereas wine from the elderberry fruits was obtained in accordance with the standard procedure of wine production. The wine was exposed to different temperature treatments in different periods (60&deg;C for 5 minutes, 60&deg;C for 10 minutes, 70&deg;C for 5 minutes and without heat treatment) to evaluate the biological activity of the product. The essential oil of the fruit and flower was obtained by hydrodistillation. The examination of the efficiency of the applied technological procedures of drying and extraction is based on observing the biological and functional characteristics of the obtained extracts of the said fruits and flowers. In the examined fruit and flower extracts, the dominant phenolic acids are chlorogenic and protocatechuic acid, while rutin and quercetin-3-O-hexoside are the dominant flavonoid compounds. Biological and functional characteristics were examined using various in vitro antioxidant, neuroprotective, antityrosinase, and antidiabetic tests. The application of lyophilization and microwave extraction (as modern drying and extraction techniques) increased the biopotential of the analyzed extracts. Elderberry juice, a potentially new functional product, was analyzed to define the chemical, phytochemical and nutritional composition, biological potential, and sensory characteristics. The wine was tested in order to determine the optimal conditions for the production of fruit wine. By defining the chemical and phytochemical composition and evaluating the biopotential of wine, the optimal temperature profile for obtaining one of the new functional products was determined. Based on the obtained chemical composition, it is determined that the essential oil of fruits and flowers is a potentially new natural agent for maintaining freshness and extending the shelf life of food products. Without a doubt, elderberry is a wild plant species that could be used in the future as the starting material for creating and obtaining new food products on the domestic and foreign markets.</p>

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