1. Nutritional quality and safety of the spirulina dietary supplements sold on the Slovenian marketJasmina Masten, Marta Jagodic Hudobivnik, Marijan Nečemer, Katarina Vogel-Mikuš, Iztok Arčon, Nives Ogrinc, 2022, izvirni znanstveni članek Opis: The microalgae Spirulina may be a popular dietary supplement rich in essential nutrients
and vitamins, but oversight of the supplement industry, in general, remains limited, and increasing
incidents of adulteration, misbranding, and undeclared ingredients together with misleading claims
create potential risks. In response, this study characterized the elemental, amino acid and fatty acid
content of commercially available Spirulina supplements in Slovenia using EDXRF, ICP-MS and
GC-MS and compared the results with their nutritional declaration. The gathered data confirm that
Spirulina supplements are a good source of calcium (0.15 to 29.5% of RDA), phosphorous (3.36–26.7%
of RDA), potassium (0.5 to 7.69% of RDA) and selenium (0.01 to 38.6% of RDA) when consumed
within recommended amounts. However, although iron contents were relatively high (7.64 to 316%
of RDA), the actual bioavailability of iron was much lower since it was mainly present as the ferric
cation. This study also confirms that pure Spirulina supplements are a good source of essential
and non-essential amino acids, and !-6 but not !-3 polyunsaturated fatty acids. The presence of
additives resulted in significant variation in nutrient content and, in some instances, lower product
quality. Moreover, a high proportion (86.7%) of inappropriate declarations regarding the elemental
content was observed. Overall, the study conclusions underline the need for a stricter control system
for Spirulina-based supplements. Ključne besede: Spirulina, microalgae, cyanobacteria, elements, toxic elements, amino acids, fatty acids, authenticity, safety, quality Objavljeno v RUNG: 24.03.2022; Ogledov: 2259; Prenosov: 0 Gradivo ima več datotek! Več... |
2. CHARACTERIZATION OF SLOVENIAN APPLE JUICE WITH RESPECT TO ITS GEOGRAPHICAL ORIGIN AND AGRICULTURAL PRODUCTION PRACTICEKarmen Bizjak Bat, 2016, doktorska disertacija Opis: Determination of food authenticity is an important issue in quality control and food safety. Recent studies predict a growing demand for natural and more authentic food and beverage products. The quality and authenticity of apple juice is also of a great economic importance since the popularity and demand for apple juice consumption has increased. The growth of the market for organically produced apples and apple juice is due to the increasing demand for healthy food requirements, protection of the environment and the promotion of biotic diversity. Organic foods have a higher nutritional and health value, but they are more expensive, because their production is more difficult and less profitable. In addition to how food is produced, consumers are increasingly placing emphasis on food products of specific region, which are known for their unique natural flavours and taste.
The presented thesis is based on four separate but closely interrelated studies, in which a combination of different isotopic ratios of bioelements (2H/1H, 13C/12C, 15N/14N, 18O/16O), multi-element analysis, and major primary and secondary metabolite profiles were exploited to differentiate the geographical origin and agricultural production practice (organic vs integrated/conventional) of Slovenian apples. These parameters were used to establish the first database of authentic Slovenian apple juice, which can be used to verify the authenticity of commercially available apple juice in Slovenia.
The first preliminary study was entitled “Organic Cultivation ~ Geographical Origin (OCGO)” and was performed using apples from the 2009 growing season. Its aim was to examine the use of stable isotope and multi-element data for determining the geographical origin and agricultural production practice of fresh apple juices. Fruits of six apple (Malus domestica Borkh) cultivars (Topaz, Idared, Golden Delicious, Goldrush, Gala, Gloster) were collected from four different geographical regions of Slovenia (Alpine, Dinaric, Pannonian and Mediterranean) grown under organic and integrated/conventional orchard management systems. The results revealed that stable isotope parameters in sugar, pulp and water were the most significant variables for differentiating between the regions. Good separation was achieved between the geographical regions in Slovenia based on the δ18O and δ2H values in water and Rb and S levels in the apple fruit juice. The most significant variables that distinguished between organically and integrated/conventionally cultivated apples were the 15N/14N ratio and antioxidant activity of the apple juice. Significant differences were also observed in the ascorbic acid content of the juice. Based on these results the number and types of apples and the minimum number of samples needed from the same region for determining geographical origin were determined.
The second study was called “Organic ~ Conventional Apple Cultivation” (OCAC) and was performed in 2010 and 2011 in a Gala apple orchard. The aim was to determine the effect of different fertilizers allowed either in organic or conventional/integrated agricultural regimes on different parameters. Quality parameters, isotopic composition of C in sugars and in pulp together with N and elemental analysis were investigated. The following five fertilizers were applied: Biosol and Plantella organic (organic) and Ca cyanamide, KAN and UREA (mineral) at a rate of 60 and 120 kg of nitrogen per hectare. From the obtained data it was possible to differentiate between organic and integrated/conventional apple production when taking into account the following parameters: mass, skin and flesh firmness (SFF), total soluble solids (TSS), and the content of Cl as well as δ15N and δ13C in the pulp.
The “Organic Cultivation ~ Geographical Origin” (OCGO) study, which took place during the 2011 and 2012 growing seasons included a greater number of samples and samples from five different geographical regions: Alpine, Dinaric, Ključne besede: apple juice, geographical origin, agricultural production practice, biomarkers, phenol compounds, elements, stable isotopes, Slovenia Objavljeno v RUNG: 07.06.2016; Ogledov: 8759; Prenosov: 907 Celotno besedilo (3,97 MB) |
3. Isotopic and elemental characterisation of Slovenian apple juice according to geographical origin: Preliminary results : /Karmen Bizjak Bat, Klemen Eler, Darja Mazej, Branka Mozetič Vodopivec, Ines Mulič, Peter Kump, Nives Ogrinc, 2016, izvirni znanstveni članek Opis: This study examined the applicability of stable isotope and multi-element data for determining the geographical
origin of fresh apple juices. Samples included three apple cultivars (Idared, Golden Delicious
and Topaz) harvested in 2011 and 2012 from five different geographical regions of Slovenia. Regional discrimination
of the juice samples was most successful when using linear discriminant analysis (LDA) and
taking into account the following parameters: d2H and d18O content of juice water; d15N and d13C content
of the pulp, (D/H)I and (D/H)II in ethanol and the concentration of S, Cl, Fe, Cu, Zn and Sr. Overall prediction
ability was 83.9%. The factors that best distinguished the different types of cultivar were the d2H and
d18O content of fruit juice water; the d13C and (D/H)I content of ethanol; and the concentration of S, Mg, K,
Cu, and Ti. Prediction ability, taking into account all ten parameters, was 75.8%. Ključne besede: Apple juice, Stable isotopes, Elemental content, Geographical origin, Slovenia Objavljeno v RUNG: 15.02.2016; Ogledov: 6730; Prenosov: 0 Gradivo ima več datotek! Več... |
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