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Characterization of oleoresin extracted from tomato waste using carbon dioxide in sub and supercritical conditions
No full textIntroduction
The food industry is characterized by a high number of wastes, nowadays they are used for agriculture or animal
feed; in particular, in Italy, the tomato processing industry produces around 150 thousand tons of wastes each year
(2-6% of the raw material). Tomato waste is characterized by high amounts of bioactive compounds such as
carotenoids, polyphenols, vitamin E and essential fatty acids. In this work oil extracts from skins and tomato waste
were produced using carbon dioxide in sub and supercritical conditions. Compositions of the oils were analyzed
and compared to the composition of oil obtained by means of solvent.
Method
Skins and tomato waste were dried at 60°C and ground to get particle size of 1 mm. Skins and tomato waste were
separately submitted to extraction by supercritical carbon dioxide, liquid carbon dioxide and hexanedichloromethane mixture solvent. Supercritical and liquid CO2 were carried out also using ethanol 10%.
Carotenoids and tocopherols were determined in the extracts by means of high-performance liquid chromatography
and spectrophotometry. Total polyphenols were determined via HPLC Diode Array/MS detector and using FolinCiocalteau method. The antioxidant capacity was measured via the DPPH method.
Results / Discussion / Conclusion
The best extraction parameters with subcritical CO2 were pressure 150 bar, temperature 20°C and flow 5 ml/min,
while for the extraction with supercritical carbon dioxide parameters were 340 bar, 60°C and 10 ml / min.
Extraction from waste with CO2 supercritical conditions with ethanol provided the highest yields in oleoresin (12.7-
12.9%), while the extracts obtained from skins with supercritical carbon dioxide without ethanol had the highest
quantities of lycopene (205.7 mg/100g oil), ß-carotene (75.1 mg/100g oil), a and γ tocopherols (800.2 and 5756.0
mg/kg oil respectively). The highest quantity of polyphenols (93 mg GAE/g oil) was found in oil from skin by
supercritical carbon dioxide with ethanol.
The oleoresin extracts from skins and tomato waste using carbon dioxide in sub and supercritical conditions
showed a great value in its antioxidant capacity (+780%) due to the presence of carotenoids, polyphenols, and
tocopherols compared to the extracts obtained with solvent
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Quality indices of cheese oxidation during storage
No full textThe objective of the work was to identify the quality indices of lipid oxidation of Grana Padano cheese and to optimize the methods for their determination. Cheese was stored at 4°C and at 20°C for 60 days. Free fatty acids (FFA) content, peroxide value (PV) and volatile organic compounds (VOC) were studied during storage. No difference for FFA values in cheese during the storage was found, while PV increased after 60 days at 20°C. The concentration of VOC increased during the storage. Results showed that VOC were the best quality indices to discriminate samples during storage
Basil (Ocimum basilicum L.) Leaves as a Source of Bioactive Compounds
Get PDFBasil (Ocimum basilicum L.) is an annual spicy plant generally utilized as a flavouring agent for food. Basil leaves also have pharmaceutical properties due to the presence of polyphenols, phenolic acids, and flavonoids. In this work, carbon dioxide was employed to extract bioactive compounds from basil leaves. Extraction with supercritical CO2 (p = 30 MPa; T = 50 °C) for 2 h using 10% ethanol as a cosolvent was the most efficient method, with a yield similar to that of the control (100% ethanol) and was applied to two basil cultivars: “Italiano Classico” and “Genovese”. Antioxidant activity, phenolic acid content, and volatile organic compounds were determined in the extracts obtained by this method. In both cultivars, the supercritical CO2 extracts showed antiradical activity (ABTS●+ assay), caffeic acid (1.69–1.92 mg/g), linalool (35–27%), and bergamotene (11–14%) contents significantly higher than those of the control. The polyphenol content and antiradical activity measured by the three assays were higher in the “Genovese” cultivar than in the “Italiano Classico” cultivar, while the linalool content was higher (35.08%) in the “Italiano Classico” cultivar. Supercritical CO2 not only allowed us to obtain extracts rich in bioactive compounds in an environmentally friendly way but also reduced ethanol consumption
Characterization of a new type of mead fermented with Cannabis sativa L. (hemp)
No full textAbstract: Mead, one of the oldest existing drinks, is a fermented product based on honey, water, and the possible addition of spices and selected yeasts. In this work, various parts (inflorescences, leaves, and steams) of Cannabis sativa L. at different concentrations and Saccharomyces cerevisiae biotype M3/5 were added during mead fermentation. The physicochemical parameters (pH, alcoholic content, sugar content, titratable acidity, and organic acids) of the mead were assessed at the beginning and end of fermentation. Moreover, polyphenols, cannabidiol and volatile organic compounds were identified at the end of fermentation and compared with the control sample prepared without hemp and with only indigenous yeasts. The mead fermented with hemp showed the highest quantity of polyphenols (227 to 256 mg GAE/L) and a level of cannabidiol ranging from 0.26 to 0.49 mg/kg. The volatile organic compounds found were mainly alcohols, esters and terpenes, which were present at higher concentrations in the mead prepared with C. sativa L. than in the control mead and conferred freshness and “hemp aroma” characteristics. Practical Application: Inflorescences, leaves, and steams of Cannabis sativa L. were added at different concentrations during mead fermentation. This type of mead showed high quantity of polyphenols (227 to 256 mg GAE/L) and a level of cannabidiol ranging from 0.26 to 0.49 mg/kg which have anxiolytic and neuro-protective properties. Moreover the volatile organic compounds found (mainly alcohols, esters, and terpenes) conferred freshness and “hemp aroma” characteristics
Bioactive compounds extracted by liquid and supercritical carbon dioxide from citrus peels
Get PDFThis work investigated the extraction of bioactive compounds from citrus peels, an agri-food waste. Carbon dioxide (CO2), an eco-friendly solvent, was used under liquid and supercritical conditions to perform the extractions from orange, tangerine and lemon peels. The possibility of using ethanol as a cosolvent at small percentages up to 20% was also studied. The extraction yield, total polyphenolic content, individual polyphenolic profile, antiradical activity and volatile organic compounds of the extracts were evaluated. The highest yields were obtained when 20% ethanol was used as a cosolvent in both liquid (at 20 MPa and 20 °C) and supercritical (at 30 MPa and 60 °C) CO2 extraction. In addition, the extracts obtained with liquid CO2 + 20% ethanol showed the highest content of naringin (35.26, 44.05 and 19.86 mg g-1 in orange, tangerine and lemon peel extracts, respectively) and terpenes, in particular limonene. This type of extract also showed the highest antiradical activity (31.78–59.51 μmolTE g-1) as measured by both ABTS·+ and DPPH·. These findings show that the extraction with a liquid CO2 and ethanol mixture could be a valid alternative to traditional solvent extraction using 80% less organic solvent and producing extracts with high antiradical capacity and rich in volatile organic compounds
Kinetics of Formation of Butyric and Pyroglutamic Acid during the Shelf Life of Probiotic, Prebiotic and Synbiotic Yoghurt
Get PDFButyric acid (C4) and pyroglutamic acid (pGlu) exert significant beneficial effects on human
health. In this study, the influence of probiotics (Lactobacillus acidophilus and Bifidobacteria) and/or
prebiotics (1 and 3% inulin and fructo-oligosaccharides) on the content of C4 and pGlu in yoghurt
during the shelf-life period was evaluated. The contents of C4 and pGlu were determined in probiotic,
prebiotic and synbiotic yoghurts during 30 days of storage at 4 ◦C by solid-phase microextraction
coupled with gas chromatography/mass spectrometry and HPLC analysis. Traditional yoghurt and
uninoculated milk were used as control. Prebiotic yoghurt contained more C4 (2.2–2.4 mg/kg) than
the uninoculated milk, and no increase was detected with respect to traditional yoghurt. However,
probiotic yoghurt showed 10% more C4 than traditional yoghurt. Adding fibre to probiotics (synbiotic
yoghurt) the C4 content increased by 30%. Regarding pGlu, probiotic yoghurt presented the highest
content of approximately 130 mg/100 g. Fibre did not affect pGlu content. Finally, C4 and pGlu
contents generally increased up to 20 days of storage and then decreased up to 30 days of storage.
The results might be useful for the preparation of other functional foods rich in C4 and pGlu using
lactic acid bacteria
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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