DSpace Collection:http://repository.afs.edu.gr/handle/6000/1122023-02-18T08:35:55Z2023-02-18T08:35:55ZMicrobial community characterization and its role in volatile compound production during inoculated and spontaneous fermentation of kiwi wine (Actinidia deliciosa cv. Tsechelidis)Tsakiroglou, Foteinihttp://repository.afs.edu.gr/handle/6000/5192022-12-01T10:05:00Z2022-09-01T00:00:00ZTitle: Microbial community characterization and its role in volatile compound production during inoculated and spontaneous fermentation of kiwi wine (Actinidia deliciosa cv. Tsechelidis)
Authors: Tsakiroglou, Foteini
Abstract: Kiwi wine is a relatively new fermented beverage developed to valorize the over-supply of kiwifruit production. Similarly to winemaking, the juice is fermented with yeast under controlled conditions (temperature, period of fermentation, and maturation). Fermentation may take place either by the naturally occurring microorganisms (spontaneously) or by the addition of selected strain(s), such as Lalvin RC212 (Saccharomyces cerevisiae, inoculated fermentation). In this study, the microbial community of both kiwi wine fermentation strategies was studied, applying modern molecular approaches. The selected microorganisms, Saccharomyces cerevisiae, total yeasts, Enterobacteriaceae and Lactobacillus were quantified using quantitative Polymerase Chain Reaction (qPCR) throughout the fermentation and maturation period. Additionally, the transcriptomic profile of Lalvin RC212 during inoculated fermentation was investigated. Genes involved in key metabolic processes, affecting the wine organoleptic profile were quantified via qPCR. ADH1, BAT1, ATF1, and ALD6 were chosen based on their role in amino acid catabolism (Ehrlich pathway), production of volatile compounds, and acetic acid. Furthermore, the aromatic profile of kiwifruit juice and inoculated and spontaneous fermentations was examined through Headspace-Solid Phase Micro-Extraction (HS-SPME) technology coupled with Gas-Chromatography and Mass-Spectrometry (GC-MS). Statistical methods were implemented to explore correlations and patterns between kiwi juice or fermentation method and volatile compounds. The results were compared with previous studies using fruits and wines of several kiwi cultivars. Our experiment is considered innovative because this is the first report utilizing the Greek kiwi cultivar “Tsechelidis”.
Description: Includes bibliographical references, tables, charts, and appendix.; MSc in New Food Product and Business Development2022-09-01T00:00:00ZHuman milk extracellular vesicle-small RNA expression and potential interdependence with maternal characteristics: a Greek contextGiannouli, Elenihttp://repository.afs.edu.gr/handle/6000/5172022-12-01T09:36:04Z2022-09-01T00:00:00ZTitle: Human milk extracellular vesicle-small RNA expression and potential interdependence with maternal characteristics: a Greek context
Authors: Giannouli, Eleni
Abstract: Human milk entails extracellular vesicles (EVs) that are transports of biological load from mother to nursling, including small RNAs. We executed the first Greek disquisition that describes the EV miRNA portrait of human milk in 11 mothers from a homogeneous population of Thessaloniki, Greece. The paper’s goals were to: (1) pinpoint ample miRNAs in human milk and inquire into the impact of milk maturity on small RNAs, (2) arrange miRNAs in groups by their expression levels, (3) describe possible biological functions of these miRNAs via gene ontology and (4) investigate whether in our study the maternal characteristics affect small RNAs. Breast milk was collected the first two months post-delivery. Via small RNA sequencing, we assessed potential pathways and ontology. Nine EV-miRNA clusters were ascertained while correlation coefficients denoted high correlation of miRNAs expression arranged in the clusters. Top-cluster human milk EV-miRNAs participate in a range of functions from metabolic and biosynthetic operations to signaling pathways, cellular adhesion, communication, growth, and differentiation. Finally, we detected the less known miR-3184 (contributes to immune system function, nutrient bioavailability, iron homeostasis or vitamin C transport).
Description: Includes bibliographical references, tables, and graphs.; MSc in New Food Product and Business Development2022-09-01T00:00:00ZThe influence of harvesting time and filtration on the quality of extra virgin olive oils extracted from Koroneiki olive fruits from higher altitude Messiniaki ManiRebholz, Anna Mariahttp://repository.afs.edu.gr/handle/6000/5142022-11-23T13:04:51Z2022-01-01T00:00:00ZTitle: The influence of harvesting time and filtration on the quality of extra virgin olive oils extracted from Koroneiki olive fruits from higher altitude Messiniaki Mani
Authors: Rebholz, Anna Maria
Abstract: Parameters playing an important role on the quality of olive oil include the olive fruits ripening stage (i.e. harvesting time) and filtration (i.e. stabilisation before storage). This study was aiming to investigate the influence of harvesting time (approximately 250 kg olives were collected five times in the period from the beginning of December until mid-February) and filtration on quality attributes of olive oils produced from Koroneiki drupes grown at higher altitude (400-450 m) in Exochori, Messiniaki Mani (Greece). The olive oil yield, defined here as kg of olives required to produce 1 kg of oil, decreased with increasing maturity index for the olives at later harvesting stages; i.e. the olive oil output increased by approximately 10-15%. All freshly pressed unfiltered and filtered samples could be classified as extra virgin olive oils (EVOOs), according to findings of acidity, peroxide and K values, and total phenols values of around 300 GAC/kg oil were observed for unfiltered samples (lower values were recorded for filtered samples). After 18 months of shelf storage in a cellar at 15 ± 5 °C the monitored acidity and K values increased but, with the exception of the K232 values, still stayed below the EU limit for EVOOs. However, higher acidity values were recorded for all unfiltered samples compared to the filtered samples at this stage. Accelerated oxidative stability tests showed an increase in peroxide values over time (up to 3.5 months at 60 °C) for all unfiltered samples and for filtered samples from the olives collected and pressed at the beginning and the end of the harvesting period. After these tests all samples, with the exception of the unfiltered sample from the end of the harvesting period, still displayed acidity values of below the 0.8% limit.
Description: Includes bibliographical references, photos, illustrations, and graphs.; MSc in New Food Product and Business Development2022-01-01T00:00:00ZInteractions of bovine serum albumin with mucin during pH cyclingLampridis, Dimitrioshttp://repository.afs.edu.gr/handle/6000/5122022-11-23T12:30:00Z2022-09-01T00:00:00ZTitle: Interactions of bovine serum albumin with mucin during pH cycling
Authors: Lampridis, Dimitrios
Abstract: The aim of this study was to characterize the diverse molecular interactions in a model system consisting of mucin which is the main viscosity enhancer of biological fluids, and BSA in a pH range of 5-9 and in various ratios of 10:0, 8:2, 6:4, 5:5, 4:6, 2:8, 0:10 of the 2 components. The mixture of mucin and BSA in a ratio of 8:2 (w/w) under acidic pH 5 led to form visible aggregates explaining also the separation of the 2 phases. At pH values of 7 and 9 the mucin redissolved due to the existence of electrostatic interactions. The viscosity of the mixtures decreased with increasing shear rate regardless of the pH value and the ratio of the 2 components in the mixture. The findings of this study highlighted the importance of understanding the physicochemical basis of the food system followed in special diets and the importance of regulating the functionality of these food systems.
Description: Includes bibliographical references, illustrations, and graphs.; MSc in New Food Product and Business Development2022-09-01T00:00:00Z