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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.
21

Olive wastewater bioremediation using a rotating biological contactor (RBC)

Tapon Njamo, Julien Serge January 2012 (has links)
Thesis (MTech (Food Technology))--Cape Peninsula University of Technology, 2012. / The expansion of the South African olive processing industry has brought an increased threat to the environment. More production activities lead to more wastewater generation that requires more costly treatment. Regulatory bodies concerned with the release of effluents into the environment are imposing evermore-restrictive guidelines. With this information in mind, the South African olive industry is facing a significant challenge of maintaining economic competitiveness while becoming more environmentally benign. To begin addressing this challenge, the olive processing industry must develop and implement new, more effective, tailored treatment technologies to remediate olive wastewater prior to its release into the environment. In this study, the use of indigenous olive wastewater biofilms in combination with a rotating biological contactor (RBC) was investigated for possible bioremediation purposes. The development of microbial biofilms resulted in the breakdown of the hazardous chemical compounds present in the olive wastewater, i.e. reducing the chemical oxygen demand (COD) and polyphenol content. Results showed that indigenous microorganisms within table olive and olive mill wastewater have a strong tendency to form biofilms. Furthermore, when these biofilms are applied to a small-scale RBC system, significant lower levels of both COD (on average 55% for table olive wastewater (TOWW) and 46% for olive mill wastewater (OMWW) and total phenol (on average 51% for TOWW and 39% for OMWW) were obtained. Results from shocking the biofilms with chemicals routinely used during olive processing indicates that most have a negative effect on the biofilm population, but that the biofilms are able to survive and recover in a relatively short time. This study confirms the potential application of indigenous biofilms found in olive wastewater streams for future bioremediation technologies that form the basis for the development of an eco-friendly, easy-to-manage, low cost technologies specifically designed for the small South African olive processing industry.
22

A emergência do sistema olivícola no Estado do Rio Grande do Sul

Rodrigues, Rodrigo Maldonado January 2016 (has links)
As preocupações, desejos e necessidades dos consumidores à jusante tendem a guiar, cada vez mais, as iniciativas dos produtores à montante e esta é uma realidade também na agricultura, com a seleção de alimentos mais saudáveis, saborosos e com valor agregado por parte dos compradores, gerando um ambiente propício para produtos com estas características. O azeite extra virgem de oliva, cujas características se enquadram nos novos hábitos alimentares, vem assumindo uma posição de destaque entre os consumidores do mundo todo e não é diferente no Brasil. A despeito da pouca tradição na produção olivícola, o Brasil e em especial o Rio Grande do Sul, ao longo da última década tem iniciado uma produção concreta deste alimento, o qual vem chegando lentamente às gôndolas dos supermercados locais e nacionais gozando de uma reputação excelente. Diante, portanto, da possível emergência deste sistema de produção agrícola, da demanda potencial deste produto e da possibilidade de satisfazê-la por meio da produção local em contraposição às importações, entendeu-se que um estudo deste fenômeno recente e por conseguinte pouco analisado pode lançar as bases teóricas para a sua compreensão. Assim, teorias ligadas à governança foram utilizadas para a identificação da organização e coordenação do sistema. Para a análise dos elementos básicos do sistema, o referencial teórico utilizado foi o de sistemas complexos e para a compreensão da relação dos elementos básicos na formação de um sistema complexo, aplicou-se o ferramental da economia institucional evolucionária. Em função deste referencial teórico e da problemática a ser trabalhada, optou-se por um método reconhecidamente institucional com uma abordagem qualitativa, ou seja, um estudo de caso em modo exploratório, realizando entrevistas com participantes considerados chave no sistema e submetendo posteriormente os dados colhidos no campo aos dados secundários e ao referencial teórico. Os resultados encontrados apontam para um gradual florescimento da organização do sistema, com a coordenação não mercadológica do setor, entende-se governança, a cargo dos governos estadual e federal, mas não foram encontrados, até o momento, indícios de uma governança por parte da base, isto é, dos produtores. No que tange ao relacionamento dos elementos para a emergência do sistema, verificou-se que esta se dá por meio das trocas de informações constantes e transações que ocorrem entre os agentes e a economia local, influenciando uns aos outros em uma dinâmica base-topo e no sentido inverso, topo-base, quando o sistema reage às influências e inicia a estimular as estruturas de governança e infra-estrutura institucional. Nesta perspectiva, entende-se que os elementos do sistema que está efetivamente emergindo foram caracterizados, bem como sua relação com a economia local e que é imprescindível, para os participantes, que este sistema complexo seja entendido e tratado como tal, com intervenções adequadas, de modo que possa, desta forma, propiciar ganhos a todos os envolvidos. / Consumers concerns, desires and necessities in downstream tend to increasingly guide initiatives of producers in the upstream and this is a reality also in agriculture, with the selection of healthier, tastier, and with higher market value food, which generates a welcoming environment for products with such characteristics. Extra virgin olive oil, whose characteristics fit in the new dietary habits, has been assuming a highlighted position among consumers from the whole world, which is not different in Brazil. Despite having little tradition in olive cultivation, Brazil, especially the state of Rio Grande do Sul, has started since the last decade a solid production of this product, which has slowly reached national and international supermarkets’ shelves while receiving an excellent reputation. Therefore, with the possible emergence of this agricultural production system, and by the high demand of the product as well as the possibility of fulfilling this demand through local production instead of imports, we assume that a study about this recent, and consequently little studied, phenomenon can provide theoretical basis for its comprehension. Hence, governance theories were used to identify the system’s organization and coordination. In order to analyze basic elements of the system, the theoretical background used was that of complex systems; for the comprehension of the basic elements’ relation in the formation of a complex system, the apparatus of institutional-evolutionary economics was applied. Having in mind this theoretical background and the problem studied, we opted for a method acknowledgedly institutional with a qualitative approach i.e. an exploratory case study conducting interviews with participants considered as fundamental in the system, submitting afterwards the data collected in field to the secondary data and the theoretical background. The results obtained point to a gradual blooming of the system’s organization, with coordination not subjected to the market action of the sector, by which is understood governance, of Federal and State responsibility. However, until the moment evidences were not found of a governance of the base i.e. the producers. In reference to the relationship of the elements for the system’s emergence, it was verified that this occurs by means of constant information exchange and transactions that occur between the agents and the local economy. The agents and the local economy influence each other reciprocally in a bottom-up dynamics and in the reverse, topdown, when the system reacts to influences and begins to stimulate governance structures and institutional infrastructure. In this perspective, it is understood that the system’s elements that are effectively emerging were characterized, as well as their relation with local economy. It is crucial for the participants that this complex system can be understood and treated as so, with adequate interventions in a way that it can propitiate gains to all parts involved.
23

The Use and Knowledge of Olive Oil and Other Lipids in a Collegiate Student Population

Benyazza, Samir 21 May 2010 (has links)
Purpose: Evidence suggests that olive oil consumption is associated with a decreased prevalence of cardiovascular disease and certain cancers. The purpose of this study was to assess the intake and knowledge of olive oil and other lipids in a collegiate population. Methods: Using an IRB-approved protocol, volunteered college students (N=56) from the college of Health and Human Sciences at Georgia State University completed a questionnaire on lipid and knowledge and eating behavior. Results were assessed to determine if students were able to accurately answer questions on the contents of different lipids, and also to determine the consumption behaviors of different lipids. Statistical comparisons were made between undergraduate and graduate students, and between students in different academic majors (nutrition, nursing, respiratory therapy, social work, criminal justice, and other). Results: It was hypothesized that eating behaviors would overemphasize unhealthy lipids. Lipids assessed included: olive oil, butter, canola oil, peanut oil, corn oil, margarine, sunflower oil, and soybean oil. There were no statistically significant differences between the ratios of consumed lipids labeled as ‘good’, and lipids labeled as ‘bad’. There were also no statistically significant differences in the presence of ‘good’ to ‘bad’ lipids in the subjects’ kitchens. Therefore, the results of this study were not able to disprove the null hypothesis. Nevertheless, using a Likert scale response scheme, there was a difference (p=0.041) between academic majors in the consumption of canola oil (an oil high in monounsaturated fatty acid), with Nursing majors reporting the highest consumption (X=3.73; SD=1.61) and Respiratory Therapy majors reporting the lowest consumption (X=1.89; SD=1.53). There was no statistically significant difference between graduate and undergraduate students in the presence of lipids in the kitchen. It was hypothesized that subject knowledge of lipid constituents would be poor. The majority of subjects either failed to respond correctly to the constituents of different lipids or reported that they did not know. Based on this result, the study is able to reject the lipid knowledge null hypothesis. There were clear differences in subgroup knowledge of commonly consumed lipids. Most notably, 100% of nutrition students responded correctly to the constituents of olive oil. Conclusions: This study focused on a group of college students in the College of Health and Human Sciences. One might assume that such a population would be sensitive and knowledgeable about key dietary factors that may influence disease risk. Nevertheless, these findings indicate that, except for isolated exceptions, the eating behaviors and lipid knowledge of these students in not at a level that could be considered health promoting. This suggests that, even with students in the health sciences, personal health classes are likely to be beneficial in reducing disease prevalence.
24

The 19th Century Olive Oil Industry In Ayvalik And Its Impact On The Settlement Pattern

Terzi, Esra 01 December 2007 (has links) (PDF)
Ayvalik which is located on the Aegean coast of the West Anatolia made its main breakthrough in the 19th century and owe this development to olive oil production which was the main economic input of the settlement since the establishment of Ayvalik. Ayvalik was within the hinterland of izmir which was gained importance as a regional trade centre in the 19th century. Thus, Ayvalik found the way to improve its trade relations in an international level and eventually increase its olive oil production volume due to the growing demands. The new form of olive oil production / factories, developed together with the traditional house and workshop productions in the last quarter of the 19th century in Ayvalik. These three forms of production made up the second significant usage within the Ayvalik after the residential areas. The two or more floored, large volumed buildings were especially located on the shore, near to the port and trade facilities, on a flat terrain and became the most dominant and attractive buildings of the settlement. Besides the impressive industrial buildings, olive oil production itself effected the settlement pattern of Ayvalik. The main transportation axes were formed accordingly to the relationship between raw material areas and production places. The olive oil production also has an effect on the physical development direction of the settlement. The areas influenced from the negative effects of the production i.e., smell and dust were not chosen for development. The development of industrial buildings also blocked the physical relationship between the residential areas and sea. The industrial buildings such as factories, workshops and warehouses along the coast line reflect the industrial character of Ayvalik in the settlement&rsquo / s silhouette.
25

The design of an Olive Oil Production Facility in the Touws River Valley.

Roodt, Miné. January 2014 (has links)
M. Tech. Architecture (Professional) / At present the South African olive oil industry is highly dependent on international imports due to local olive oil producers being unable to meet the local demand. The need for extra virgin olive oil has increased each year since people have become more aware of the health benefits of the product. This dissertation documents the design of an olive oil production facility near the foothills of the Draaiberg mountain range in the Touws River valley. Situated in close proximity to the Touws River railway station, the proposed architectural intervention responds to the current situation of neglected railway towns through the implementation of agri-tourism in the area. Public interest creates a platform for the market to educate the broader public about health benefits, which has caused a gradual, growth in the olive oil industry. This in turn shows that olive oil farms need a public interface, such as an information centre, a shop and tasting room to entice the consumer and create awareness of the quality level of olive oil South Africa has to offer. The aim of this thesis is to design an olive oil production facility, focusing on the production of extra virgin olive oil and relevant alternative products. The facility will not only function as an agricultural olive press for a private farming concern, but will also act as a community press facility to allow for continuous growth in the olive industry. One of the design objectives is to create a space for information and social interaction. The main building's size is informed by the size of the productive landscape and formulas were used to calculate the volume of oil produced per hectare. The production process can be followed by the visitor, giving rise to a linear building typology.
26

Volatile Organic Compounds and Antioxidants in Olive Oil: Their Analysis by Selected Ion Flow Tube Mass Spectrometry

Davis, Brett Murray January 2007 (has links)
The application of Selected Ion Flow Tube Mass Spectrometry (SIFT MS) to the analysis of olive oil shows several distinct advantages over more conventional analysis techniques. The two areas described in this thesis examining olive oil quality are the analysis of Volatile Organic Compounds (VOCs) and the assessment of antioxidant activity. VOCs are responsible for the aroma and much of the taste of olive oil, while antioxidants afford some protection from harmful reactions involving radical species inside the body by scavenging radicals when olive oil is ingested. The VOCs of olive oil are used by sensory panel judges to classify oils by their degree of suitability for human consumption. The major parameters used for this evaluation are the strengths of any defects and the degree of fruitiness. A defect is an indication of an undesired process which has occurred in the oil, while fruitiness is a fragile attribute which denotes a good quality oil and is easily masked by defects. SIFT MS was used to measure the strengths of the olive oil defects rancid, winey, musty, fusty and muddy. Great potential was demonstrated for all defects except musty and the concentrations of VOCs in olive oil head space were correlated with the peroxide value, a measure of the degree of oil oxidation. A study aimed at correlating the strength of the fruitiness attribute as determined by a sensory panel with the concentrations of VOCs in olive oil head space was unsuccessful. The SIFT MS Total Oxyradical Scavenging Capacity (TOSC) assay was used to measure olive oil antioxidants. This assay measures all antioxidants in oil, not only those removed by extraction with a solvent, as it is conducted in an emulsion. SIFT MS TOSC assay results were found to correlate well with those of the widely used Folin Ciocalteu assay and the total concentration of phenolic compounds present in olive oil. Discrepancies between the two assays were most likely due to hydrophobic antioxidants which are measured by the SIFT MS TOSC assay but not the other tests.
27

Volatile Organic Compounds and Antioxidants in Olive Oil: Their Analysis by Selected Ion Flow Tube Mass Spectrometry

Davis, Brett Murray January 2007 (has links)
The application of Selected Ion Flow Tube Mass Spectrometry (SIFT MS) to the analysis of olive oil shows several distinct advantages over more conventional analysis techniques. The two areas described in this thesis examining olive oil quality are the analysis of Volatile Organic Compounds (VOCs) and the assessment of antioxidant activity. VOCs are responsible for the aroma and much of the taste of olive oil, while antioxidants afford some protection from harmful reactions involving radical species inside the body by scavenging radicals when olive oil is ingested. The VOCs of olive oil are used by sensory panel judges to classify oils by their degree of suitability for human consumption. The major parameters used for this evaluation are the strengths of any defects and the degree of fruitiness. A defect is an indication of an undesired process which has occurred in the oil, while fruitiness is a fragile attribute which denotes a good quality oil and is easily masked by defects. SIFT MS was used to measure the strengths of the olive oil defects rancid, winey, musty, fusty and muddy. Great potential was demonstrated for all defects except musty and the concentrations of VOCs in olive oil head space were correlated with the peroxide value, a measure of the degree of oil oxidation. A study aimed at correlating the strength of the fruitiness attribute as determined by a sensory panel with the concentrations of VOCs in olive oil head space was unsuccessful. The SIFT MS Total Oxyradical Scavenging Capacity (TOSC) assay was used to measure olive oil antioxidants. This assay measures all antioxidants in oil, not only those removed by extraction with a solvent, as it is conducted in an emulsion. SIFT MS TOSC assay results were found to correlate well with those of the widely used Folin Ciocalteu assay and the total concentration of phenolic compounds present in olive oil. Discrepancies between the two assays were most likely due to hydrophobic antioxidants which are measured by the SIFT MS TOSC assay but not the other tests.
28

Olive oil : phytosterols, tracing of adulteration with hazelnut oil and chemical interesterification /

Azadmard-Damirchi, Sodeif, January 2007 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 4 uppsatser.
29

Εκτίμηση της οικολογικής ποιότητας των απορροών από διαφορετικές μεθόδους επεξεργασίας των ελαιουργικών αποβλήτων

Ρούβαλη, Αγγελική 08 February 2010 (has links)
Η Ελλάδα αποτελεί μία από τις βασικές ελαιοπαραγωγικές χώρες, καλύπτοντας το 17% της παγκόσμιας παραγωγής. Η παραγωγική διαδικασία λαμβάνει χώρα σε ελαιοτριβεία φυγοκεντρικού τύπου τριών φάσεων και δύο φάσεων. Στην πρώτη περίπτωση, παράγονται τρεις εκροές, το ελαιόλαδο, το υγρό απόβλητο και η παχύρευστη ελαιοπυρήνα. Στη δεύτερη περίπτωση, εκτός από το ελαιόλαδο προκύπτει και ένα παχύρευστο παραπροϊόν, η υγρή ελαιοπυρήνα. Τα παραπροϊόντα της ελαιοπαραγωγικής διαδικασίας, λόγω της απευθείας διάθεσης στο έδαφος ή στα ποτάμια ή στη θάλασσα, επιδρούν δυσμενώς και στο περιβάλλον λόγω του υψηλού οργανικού φορτίου και της τοξικής δράσης ορισμένων συστατικών τους. Για το λόγο αυτό υπάρχουν πολυάριθμες βιβλιογραφικές αναφορές σχετικές με μεθόδους επεξεργασίας του αποβλήτου, που αφορούν σε φυσικές, χημικές, βιολογικές μεθόδους, με τις τελευταίες να είναι πιο διαδεδομένες και να θεωρούνται πιο αποτελεσματικές. Η παρούσα μελέτη στοχεύει στην εκτίμηση του κινδύνου του ελαιουργικού αποβλήτου για το υδάτινο οικοσύστημα και της αποτελεσματικότητας τριών βιολογικών μεθόδων επεξεργασίας του, ως προς τη μείωση της τοξικότητας, με σκοπό την ασφαλή διάθεση στο περιβάλλον. Πραγματοποιήθηκαν μετρήσεις των φυσικοχημικών παραμέτρων των απορροών που προέκυψαν από την επεξεργασία του αποβλήτου με τον μύκητα Pleurotus ostreatus, καθώς και από την αναερόβια επεξεργασία σε αντιδραστήρες για παραγωγή υδρογόνου και μεθανίου. Η αποτελεσματικότητα των μεθόδων ελέγχθηκε μέσω της οικοτοξικολογικής προσέγγισης με τη χρήση των μικροβιοτεστ Thamnotoxkit F και Daphtoxkit FTM pulex και του τεστ τοξικότητας με έμβρυα ιχθύος (Danio rerio). Θα πρέπει να επισημανθεί ότι ανάλογη ολοκληρωμένη μελέτη τοξικότητας των αποβλήτων των ελαιουργείων δεν έχει γίνει στη χώρα μας, γεγονός που καθιστά την όλη προσπάθεια ιδιαίτερα ενδιαφέρουσα. Λήφθηκαν 7 δείγματα ανεπεξέργαστου ελαιουργικού αποβλήτου, 16 δείγματα από την επεξεργασία με P. ostreatus, 50 δείγματα από τον αναερόβιο αντιδραστήρα για παραγωγή υδρογόνου και 25 από τον αντιδραστήρα για παραγωγή μεθανίου. Η επίπτωση του ελαιουργικού αποβλήτου στα υδάτινα οικοσυστήματα και συγκεκριμένα σε ποτάμι, πραγματοποιήθηκε με την εφαρμογή της μεθοδολογίας για την εκτίμηση κινδύνου, μέσω του λόγου RQ (Risk Quotient) από όπου προέκυψε ότι ο κίνδυνος είναι ιδιαίτερα υψηλός. Η φυσικοχημική ανάλυση των δειγμάτων έδειξε υψηλές τιμές στις παραμέτρους που αναλύθηκαν, ακόμα και μετά την επεξεργασία, καθώς και μεγάλη διακύμανση αυτών σε δείγματα της ίδιας κατηγορίας. Από τους ελέγχους τοξικότητας που εφαρμόστηκαν, υπολογίσθηκαν οι τιμές τοξικότητας LC50 και εν συνεχεία οι τοξικές μονάδες (ΤU). Μέσω αυτών, το ελαιουργικό απόβλητο κατατάσσεται στην κατηγορία «πολύ τοξικό» (D. pulex) και «εξαιρετικά τοξικό» (Τ. platyurus και D. rerio), με τιμές ΤU να κυμαίνονται από 60,2 – 330,9. Η τοξικότητα συνδέεται άμεσα με τις φαινόλες, τα νιτρώδη, τα αμμωνιακά, τις τανίνες, τα θειικά ιόντα, τα ολικά χλωριόντα και τα ολικά διαλυμένα στερεά. Η απορροή της πρώτης μεθόδου επεξεργασίας (με P. ostreatus), είχε μειωμένες συγκεντρώσεις φαινολικών και τανίνων και υψηλές εκείνες των υπόλοιπων παραμέτρων. Σύμφωνα με τους ελέγχους τοξικότητας με Daphtoxkit pulex και Thamnotoxkit, αυτή συσχετίζεται με τα αμμωνιακά, τις φαινόλες και τα ολικά διαλυμένα στερεά, ενώ στα zebrafish δεν εμφάνισαν συσχέτιση. Η απορροή χαρακτηρίστηκε «πολύ τοξική» (TU = 52,4 – 91,5). Στην αναερόβια επεξεργασία για παραγωγή υδρογόνου χρησιμοποιήθηκαν δύο τύποι αποβλήτου: υγρό απόβλητο από ελαιοτριβείο τριών φάσεων και ελαιοπολτός από ελαιοτριβείο δύο φάσεων. Οι έλεγχοι τοξικότητας με τα καρκινοειδή χαρακτήρισαν και τους δύο τύπους απορροών «πολύ τοξικές» (TU = 26,8 – 68,7) ενώ με το zebrafish το υγρό απόβλητο κρίθηκε «εξαιρετικά τοξικό» (TU = 132,2) και ο ελαιοπολτός «πολύ τοξικός» (TU = 73,5). Η D. pulex επηρεάστηκε από τα ιόντα NO-3, NO-2 , SO-24 , Cl- και το COD του υγρού αποβλήτου, ενώ υπήρξε συσχέτιση με όλους τους παράγοντες του ελαιοπολτού εκτός του COD. Οι τιμές του COD συσχετίστηκαν με τις τιμές τοξικότητας του Thamnotoxkit και στους δύο τύπους απορροών, ενώ το zebrafish εμφάνισε ευαισθησία έναντι των νιτρωδών, νιτρικών, αμμωνιακών και χλωριόντων του υγρού αποβλήτου και μόνο στις συγκεντρώσεις των φαινολικών του ελαιοπολτού. Κατά την αναερόβια επεξεργασία για παραγωγή μεθανίου οι έλεγχοι τοξικότητας κατέταξαν την απορροή στην κατηγορία «πολύ τοξική» (TU = 23,9 – 45,5). Οι τιμές τοξικότητας του Daphtoxkit συσχετίστηκαν με τα νιτρικά, τα αμμωνιακά, το pH και την αγωγιμότητα, ενώ οι τιμές που προέκυψαν από το Thamnotoxkit επηρεάστηκαν από τις φαινόλες, τις τανίνες και τις λιγνίνες. Και σε αυτή την περίπτωση, το zebrafish, δεν φάνηκε να επηρεάζεται από τις παραμέτρους που αναλύθηκαν. Σύμφωνα με τα αποτελέσματα των ελέγχων με zebrafish, που ήταν το πιο ευαίσθητο είδος, η τοξικότητα της απορροής μειώθηκε σε σχέση με το ανεπεξέργαστο απόβλητο κατά 60% στην επεξεργασία με μύκητα, 65% στην αναερόβια χώνευση για παραγωγή υδρογόνου και 86% στην αναερόβια χώνευση για παραγωγή μεθανίου. Ωστόσο η εκροή παραμένει στη «πολύ τοξική» κατηγορία ώστε να μην θεωρείται ασφαλής για διάθεση στο περιβάλλον. Παράλληλα, πραγματοποιήθηκε ανίχνευση μικροβιακών πληθυσμών στο ελαιουργικό απόβλητο και στο αναερόβια επεξεργασμένο για παραγωγή υδρογόνου. Ανιχνεύτηκαν τόσο οργανισμοί που αποδομούν τις φαινολικές ενώσεις (Pseudomonas aeruginosa) όσο και παθογόνοι (Citrobacter, Enterobacter clocae, Aeromonas hydrophila, Pseudomonas sp.), οι οποίοι εμφάνισαν συσχέτιση με τα αποτελέσματα των ελέγχων τοξικότητας με zebrafish, ερμηνεύοντας σε κάποιο βαθμό την ευαισθησία του είδους. Εμφανίστηκαν διαφορές μεταξύ των μικροβιακών πληθυσμών στους δύο τύπους αποβλήτου, με μόνο κοινό είδος το Enterobacter clocae. Τέλος, με τη χρήση της ατομικής απορρόφησης ανιχνεύτηκαν βαρέα μέταλλα, τα οποία θεωρείται ότι προκάλεσαν τις παρατηρηθείσες δυσμορφίες στα έμβρυα του zebrafish μετά από έκθεση 7 ημερών, όπως έλλειψη χρώσης και σκελετικές δυσμορφίες. Οι μέσοι όροι των συγκεντρώσεων των βαρέων μετάλλων στα δείγματα κυμάνθηκαν μεταξύ 3,645 – 6,074 μg Hg/l, 0,488 – 1,017 mg Cu/l, 0,137 – 0,712 mg Mn/l, 0,190 – 3,198 mg Zn/l, 0,205 – 0,505 mg Cr/l, μη ανιχνεύσιμο - 0,106 mg Cd/l και 0,135 – 0,271 mg Pb/l. Συμπεραίνεται ότι η τοξικότητα των απορροών προκαλείται από συνδυασμό παραμέτρων, μεταξύ των οποίων περιλαμβάνονται οι φαινόλες, οι τανίνες, τα αμμωνιακά, τα νιτρικά και τα νιτρώδη. Εκτός αυτών όμως, εκτιμάται ότι συνεισφέρουν στην τοξικότητα και οι μικροβιακοί πληθυσμοί αλλά και τα βαρέα μέταλλα. Οι αναφερθείσες μέθοδοι επεξεργασίας αποδεικνύονται ιδιαίτερα αποτελεσματικές στη μείωση της τοξικότητας του ελαιουργικού αποβλήτου, με τη μέθοδο της αναερόβιας χώνευσης για παραγωγή μεθανίου να αναδεικνύεται η πιο αποτελεσματική. Ωστόσο η μείωση αυτή δεν είναι αρκετή για να καταστήσει την εκροή ασφαλή για απόρριψη σε υδάτινα οικοσυστήματα. Τέλος, η παρούσα μελέτη προσφέρει νέα δεδομένα που μπορούν να χρησιμοποιηθούν από την επιστημονική κοινότητα για την αναζήτηση και ανάπτυξη περιβαλλοντικά φιλικότερων μεθόδων επεξεργασίας των συγκεκριμένων αποβλήτων, αλλά και εργαλεία στους αρμόδιους θεσμικούς φορείς για τη συστηματική παρακολούθηση και τον έλεγχο των επιπτώσεων σύνθετων αποβλήτων στο περιβάλλον. / Greece is one of the major olive oil producing countries, covering 17% of the worldwide production. In the recent years, the productive process takes place in centrifugal type olive oil mills of three phases and two phases. In the first case, three outflows are produced, the olive oil, the liquid wastewaters and oil-stone. In the second case, apart from olive oil, the by-product is a semi-solid waste called olive pulp. The by-products of the olive oil process provoke serious repercussions to the environment from the uncontrolled disposal to the soil and to the rivers or to the sea, because of the high organic load and the especially toxic action of certain components. For this reason many bibliographic reports exist regarding treatment methods of this waste, which include physical, chemical and biological methods, with the last to be considered more effective. The present study aims to the risk assessment of olive oil mill wastewaters (OMW) posed to aquatic ecosystems and to the estimation of the effectiveness of three biological treatment methods regarding the reduction of toxicity, driving to safe environmental disposal. Analyses of the physicochemical characteristics were conducted for the effluents that resulted from the treatment of the waste with the white rot fungus Pleurotus ostreatus, as well as from the anaerobic treatment in reactors for hydrogen and methane production. The effectiveness of the aforementioned methods was validated via the ecotoxicological approach with the use of the two microbiotests Thamnotoxkit F and Daphtoxkit FTM pulex and the embryo toxicity test of the zebrafish Danio rerio. It must be noted that a similar integrated study has not been conducted not only in Greece but worldwide, a fact rendering the whole effort especially interesting. Seven (7) samples of the untreated OMW were collected from a three phase system, 16 samples from the outflow of the treatment with P. ostreatus, 50 samples from the anaerobic reactor for hydrogen production and 25 samples from the methane producing reactor. The repercussion of OMW to the aquatic ecosystems and specifically to a river, was realised with the application of the risk assessment methodology, via the Risk Quotient (RQ). The results indicate that the risk is quite high seasonally. The physicochemical analyses of the samples revealed high values in the parameters that were analyzed, even after the treatments, as well as a high deviation of the values, even in samples of the same category. The toxicity test results were expressed in LC50 values according to the test protocols that were transformed to toxic units (TU), in order to categorize the samples. The untreated samples were classified in the category “very toxic” (against D. pulex) and “extremely toxic” (against T. platyurus and D. rerio), with TU values that oscillated from 60,2 - 330,9. The toxicity appears to be influenced considerably by phenols but also by nitrates, ammonium, tannins, the sulphuric ions, total chlorine and total dissolved solids. The first treatment method (with P. ostreatus), resulted in an effluent with decreased concentrations of phenols and tannins, but the remaining toxic parameters had high values. The results of the toxicity tests with Daphtoxkit pulex and Thamnotoxkit were correlated with ammonium, phenols and total dissolved solids, while zebrafish were not cross-correlated. The outflow was characterized as “very toxic”, while the TU oscilated from 52,4 - 91,5. In the anaerobic treatment for hydrogen production two types of wastes were used: liquid wastewaters and olive pulp from a three phase and two phase olive oil mill respectivelly. Toxicity tests with the crustaceans characterized the two types of outflows as “very toxic” (TU = 26,8 - 68,7) while according to the zebrafish test only the liquid wastewater was assessed as “exceptionally toxic” (TU = 132,2) whereas the olive pulp as “very toxic” (TU = 73,5). D. pulex was influenced by ions such as NO-3, NO-2 , SO-24 , Cl- and COD from the treated OMW, whereas all parameters from the olive pulp revealed good correlation to D. pulex with the exception of COD. The results from the Thamnotoxkit test correlated with COD in both types of effluents, while zebrafish presented a sensitivity against the concentrations of nitrates, nitrites, ammonium and chlorine. In the case of anaerobic treatment for the production of methane the toxicity tests classified the outflow in the category “very toxic” (TU = 23,9 - 45,5). The toxicity values of Daphtoxkit were correlated with nitrites, ammonium, pH and conductivity, while the values that resulted from Thamnotoxkit were influenced by phenols, tannins and lignin. Also in this case, zebrafish, it did not appear to be influenced from the analyzed parameters. According to the results of the zebrafish tests that were the most sensitive, the toxicity of the treated effluents was decreased compared to that of the untreated wastewaters, by 60% in the treatment with the white rot fungi, 65% in the anaerobic reactor for hydrogen production and 86% in the anaerobic reactor for the production of methane. All outflows however remain in the “very toxic” category so they are not considered acceptable for environmental disposal. In addition to the above, microbial populations in the untreated OMW and in the effluent from the anaerobic processe for hydrogen production were detected. Organisms that degrade phenolic compounds were detected (Pseudomonas aeruginosa), as well as others that are considered as pathogens (Citrobacter sp., Enterobacter clocae, Aeromonas hydrophila, Pseudomonas sp.). The later presented cross-correlation with the results of the zebrafish toxicity tests, interpreting in some degree the sensitivity of the species. The microbial flora was differentiated between the untreated and treated effluent presenting only one common species, namely Enterobacter clocae. Finally, heavy metals were detected in all outflows, which are considered to cause malformations that were observed in this study in zebrafish embryos after a 7-day test. These included lack of pigmentation and spinal deformities. The mean values oscillated between 3,645 - 6,074 μg Hg/l, 0,488 - 1,017 mg Cu/l, 0,137 - 0,712 mg Mn/l, 0,190 - 3,198 mg Zn/l, 0,205 - 0,505 mg Cr/l, not detected- 0,106 mg Cd/l and 0,135 - 0,271 mg Pb/l. In conclusion, the toxicity of the analyzed samples was caused by a combination of parameters, which included phenols, tannins, ammonium, nitrites and nitrates. However, besides these, the microbial populations but also the heavy metals that were detected probably contribute to the observed toxicity. The particular treatment methods proved to be especially effective in the reduction of toxicity of olive oil mill wastewaters, but the reduction is not capable to render the outflow as safe for disposal in aquatic ecosystems. Finally, the current study offers data that could be utilized by the relative scientists in order to develop more environmentally friendly methods for the treatment of this specific effluents and additionally provides tools to the government officials for the systematic monitoring and controlling of such complex and hazardous effluents.
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Desenvolvimento e aplicação de filmes biodegradáveis com antioxidantes extraídos a partir de bagaço de uva, um resíduo da indústria vitivinícola

Stoll, Liana January 2015 (has links)
O consumo abusivo de embalagens plásticas tem causado diversos problemas ambientais, visto que as mesmas são produzidas a partir de fontes não renováveis de energia e são resistentes à degradação. Neste contexto, o desenvolvimento de filmes biodegradáveis ativos para aplicação em alimentos é de grande importância pois, além de serem produzidos a partir fontes renováveis e mais sustentáveis, os mesmos podem interagir com o produto embalado e proporcionar benefícios extras em relação aos filmes convencionais. Este trabalho utilizou o bagaço de uva proveniente do processo de vinificação como fonte de antocianinas para o desenvolvimento de filmes biodegradáveis com propriedades antioxidantes. A microencapsulação das antocianinas, realizada com a finalidade de aumentar sua estabilidade, utilizou maltodextrina e goma arábica como agentes encapsulantes. Diferentes formulações de filmes biodegradáveis foram desenvolvidas com as microcápsulas produzidas. Goma arábica, maltodextrina e a combinação das mesmas foram eficientes no processo de microencapsulação (>90% de retenção de antocianinas). Apesar de apresentarem o mesmo teor de antocianinas - quantificadas via cromatografia líquida de alta eficiência - a atividade antioxidante das microcápsulas de goma arábica foi maior. A diferença entre a atividade antioxidante das cápsulas foi atribuída às diferentes solubilidades destas em água, onde maiores solubilidades poderiam liberar mais facilmente as antocianinas encapsuladas. O filme desenvolvido a partir de antocianinas encapsuladas com maltodextrina apresentou melhores propriedades mecânicas e ofereceu maior proteção ao óleo de girassol frente às reações de oxidação, e portanto foi utilizado na produção de sachês de azeite de oliva extra-virgem. O filme desenvolvido apresentou biodegradabilidade comprovada e propiciou maior estabilidade oxidativa ao azeite de oliva nele embalado quando comparado a um azeite embalado em polipropileno comercial. Os resultados obtidos neste trabalho comprovam a potencialidade da utilização de maltodextrina como encapsulante de antocianinas e como ingrediente na produção de filmes biodegradáveis, aplicados principalmente em produtos gordurosos. / The abuse of plastic packaging has caused various environmental problems, since they are produced from non-renewable sources of energy and are resistant to degradation. In this context, the development of active biodegradable films for application in foods is of great importance, since they are produced from renewable and sustainable sources, besides they may interact with the packaged product and provide additional benefits over conventional films. This study used the wine grape pomace as a source of anthocyanins for the development of biodegradable films with antioxidant properties. Microencapsulation of anthocyanins, which was carried out with the purpose of increasing its stability, used maltodextrin and gum arabic as wall materials. Different formulations of biodegradable films were developed with the obtained microcapsules. Gum arabic, maltodextrin and their combination were effective in the microencapsulation process (> 90% retention of anthocyanins). Despite being provided with the same anthocyanins content - quantified by highperformance liquid chromatography - the antioxidant activity of gum arabic microcapsules was greater. The difference between the antioxidant activity of the capsules was attributed to their different solubility in water, so that capsules with higher solubility could release more easily the encapsulated anthocyanins. The film containing anthocyanins encapsulated with maltodextrin showed better mechanical properties and offered greater protection to sunflower oil against oxidation reactions, and so was used in the production of extra-virgin olive oil pouches. The developed film, which was proven to be biodegradable, increased the oxidative stability of the olive oil when compared to olive oil packaged in a commercial polypropylene. The results of this study demonstrate the potential usage of maltodextrin as wall material on encapsulation of anthocyanins and as an ingredient in the production of biodegradable films, mainly applied in fatty products.

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