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131.
Donatella Albanese Giuseppina Adiletta Mariantonietta D′Acunto Luciano Cinquanta Marisa Di Matteo 《International Journal of Food Science & Technology》2014,49(11):2458-2463
Tomato peels were firstly dried by different methods (hot air, freeze‐drying, and fluidized bed drying) to evaluate the recovery of lycopene, β‐carotene and DPPH radical scavenging activity. Comparison of the results showed that hot air drying at 50 °C was a suitable method and alternative to freeze‐drying to preserve carotenoids compounds and antioxidant activity in tomato peels. Then, ethanol/ethyl acetate (1:1) extracts from tomato peel, previously dried at 50 °C by hot air, were submitted to heat (100 °C) and light treatment (1000 lumen) to evaluate their stability as natural food dyes. Heating of the extracts caused a progressive reduction of total carotenoids, up to about 30% after 250 min of treatment, whereas the colour at the end of heat treatment showed small changes, with an overall colour difference (?E) equal to 7. Fluorescent lighting treatment showed an almost total degradation of carotenoids in the extracts after 48 h combined with a fading colour. 相似文献
132.
Giuseppina Montante Fabio Laurenzi Alessandro Paglianti Franco Magelli 《Chemical Engineering Research and Design》2011,89(11):2262-2267
The influence of the addition of a drag reducing agent (100 ppm PAA) to a pure liquid (water) in a stirred vessel has been studied. The vessel was stirred with two types of agitators, a Rushton turbine and an axial A310 impeller.This study was meant to implement previous findings with new data and various types of measurements were performed to determine a number of parameters. It is confirmed that the drag-reducing agent decreases power draw and increases mixing time. Mean flow and the fluctuating velocities were determined (with the PIV technique) and notable reduction in turbulence intensity was detected. The mechanism of tracer dispersion (followed by the PLIF technique) was also documented qualitatively. Finally, the influence of the drag-reducing agent on the particle size distribution of the solid product of a precipitation reaction (reaction of barium chloride and sodium sulphate) was shown. 相似文献
133.
Luca Laghi Andrea Versari Giuseppina P. Parpinello David Y. Nakaji Roger B. Boulton 《Food Analytical Methods》2011,4(4):619-625
The composition of phenolic compounds plays an important role in food science and nutrition; thus, there is a need of a new
method of analysis that is able to speed up the monitoring of product quality parameters. In this view, the amount of selected
color components of 145 commercial red wines (total wine color, polymeric pigments, total anthocyanins, and copigmentation index) was investigated using Fourier transform mid-infrared spectroscopy (MIR) combined with partial least squares (PLS) regression.
The feasibility of several preprocessing algorithms (first and second derivative, standard normal variate, and direct orthogonal
signal correction) was compared in terms of coefficient of determination (R
2) and root mean square error of prediction using an independent test set of wines. The composition of red wines showed great
difference in terms of total color (5.07 ± 1.95 AU at 520 nm) compared to copigmentation index (0.66 ± 0.58 AU at 520 nm).
The best prediction model was obtained using direct orthogonal signal correction (DOSC) preprocessing. In particular, the
prediction of total wine color, total anthocyanins, and polymeric pigments showed a good fitting (R
2 ≥ 0.82), whereas copigmentation index was more difficult to be predicted by FTIR (R
2 = 0.57). This preliminary study showed the potential of MIR spectroscopy with DOSC–PLS algorithm to successfully analyze selected color components of red wine on a large number
of samples in short time with almost no sample preparation and no chemical waste is created. 相似文献
134.
Teresa Lavecchia Giuseppina Rea Amina Antonacci Maria T. Giardi 《Critical reviews in food science and nutrition》2013,53(2):198-213
In recent years, both food quality and its effect on human health have become a fundamental issue all over the world. As a consequence of this new and increased awareness, American, European, and Asian policymakers have strongly encouraged the research programs on food quality and safety thematic. Attempts to improve human health and to satisfy people's desire for healthcare without intake of pharmaceuticals, has led the food industry to focus attention on functional or nutraceutical food. For a long time, compounds with nutraceutical activity have been produced chemically, but the new demands for a sustainable life have gradually led the food industry to move towards natural compounds, mainly those derived from plants. Many phytochemicals are known to promote good health, but, sometimes, undesirable effects are also reported. Furthermore, several products present on the market show few benefits and sometimes even the reverse - unhealthy effects; the evidence of efficacy is often unconvincing and epidemiological studies are necessary to prove the truth of their claims. Therefore, there is a need for reliable analytical control systems to measure the bioactivity, content, and quality of these additives in the complex food matrix. This review describes the most widespread nutraceutics and an analytical control of the same using recently developed biosensors which are promising candidates for routine control of functional foods. 相似文献
135.
Textural properties and changes of myofibrillar and sarcoplasmic proteins of salame Felino, a typical Italian dry-cured fermented sausage, were studied during ripening. Hardness, chewiness, and gumminess increased over the ripening period. Adhesiveness showed a gradual but significant decrease after 14 days and further at 28 days of ripening. A remarkable increase of the proteolysis index and a significant decrease of myofibrillar and sarcoplasmic protein solubility were observed. Hardness showed a significant negative correlation with myofibrillar protein solubility. Sarcoplasmic proteins appeared to be more susceptible to degradation. 相似文献
136.
Salvatore Cafiso Alessandro Di Graziano Giuseppina Pappalardo 《Accident; analysis and prevention》2013
Because of the low percentage of crashes involving buses and the assumption that public transport improves road safety by reducing vehicular traffic, public interest in bus safety is not as great as that in the safety of other types of vehicles. It is possible that less attention is paid to the significance of crashes involving buses because the safety level of bus systems is considered to be adequate. 相似文献
137.
Dr. Barbara Rolando Dr. Loretta Lazzarato Dr. Monica Donnola Dr. Elisabetta Marini Dr. Sony Joseph Prof. Dr. Giuseppina Morini Dr. Cristina Pozzoli Prof. Roberta Fruttero Prof. Alberto Gasco 《ChemMedChem》2013,8(7):1199-1209
A series of water‐soluble (benzoyloxy)methyl esters of acetylsalicylic acid (ASA), commonly known as aspirin, are described. The new derivatives each have alkyl chains containing a nitric oxide (NO)‐releasing nitrooxy group and a solubilizing moiety bonded to the benzoyl ring. The compounds were synthesized and evaluated as ASA prodrugs. After conversion to the appropriate salt, most of the derivatives are solid at room temperature and all possess good water solubility. They are quite stable in acid solution (pH 1) and less stable at physiological pH. In human serum, these compounds are immediately metabolized by esterases, producing a mixture of ASA, salicylic acid (SA), and of the related NO‐donor benzoic acids, along with other minor products. Due to ASA release, the prodrugs are capable of inhibiting collagen‐induced platelet aggregation of human platelet‐rich plasma. Simple NO‐donor benzoic acids 3‐hydroxy‐4‐(3‐nitrooxypropoxy)benzoic acid ( 28 ) and 3‐(morpholin‐4‐ylmethyl)‐4‐[3‐(nitrooxy)propoxy]benzoic acid ( 48 ) were also studied as representative models of the whole class of benzoic acids formed following metabolism of the prodrugs in serum. These simplified derivatives did not trigger antiaggregatory activity when tested at 300 μM . Only 28 displays quite potent NO‐dependent vasodilatatory action. Further in vivo evaluation of two selected prodrugs, {[2‐(acetyloxy)benzoyl]oxy}methyl‐3‐[(3‐[aminopropanoyl)oxy]‐4‐[3‐(nitrooxy)propoxy]benzoate?HCl ( 38 ) and {[2‐(acetyloxy)benzoyl]oxy}methyl 3‐(morpholin‐4‐ylmethyl)‐4‐[3‐(nitrooxy)propoxy]benzoate oxalate ( 49 ), revealed that their anti‐inflammatory activities are similar to that of ASA when tested in the carrageenan‐induced paw edema assay in rats. The gastrotoxicity of the two prodrugs was also determined to be lower than that of ASA in a lesion model in rats. Taken together, these results indicated that these NO‐donor ASA prodrugs warrant further investigation for clinical application. 相似文献
138.
Lidiane Coffacci Lucia Codognoto Luciana F. Fleuri Giuseppina P. P. Lima Valber A. Pedrosa 《Food Analytical Methods》2013,6(4):1122-1127
Vegetables were analyzed for total N-nitrosamines (NAs) and the influence of disinfection processes was assessed. Differences in NAs found in cabbage, spinach, and broccoli were determined by square wave voltammetry using a boron-doped diamond electrode. Analysis of samples showed that all samples contained detectable levels of NAs but the results indicated that organic contained less than conventionally grown products. The sum of the total NAs was higher in the cabbage samples, ranging between 2.8–3.1 ppb and lower in broccoli samples at 0.2–1.1 ppb. The method described is simple, rapid, selective, and sensitive. The results suggested that the disinfection process affects the level of NAs, in this manner affecting the level of human exposure to NAs. 相似文献
139.
140.
Leonardo Petruzzi Antonio Bevilacqua Claudio Ciccarone Giuseppe Gambacorta Giuseppina Irlante Sandra Pati Milena Sinigaglia 《Journal of the science of food and agriculture》2010,90(15):2617-2626
BACKGROUND: Oak barrels are commonly used in the aging of wines and spirits because of their positive effects on the product. In recent years the addition of oak chips has been used to introduce desirable wood aromas and flavours into wines. In this study, oak chips in saline solution or laboratory medium were inoculated with Penicillium purpurogenum, Aureobasidium pullulans, Phialemonium obovatum, Phanerochaete chrysosporium and a combination of Ph. chrysosporium and A. pullulans. After 12 weeks of incubation, oak chips (2 g L?1) were macerated in a red wine for 17 days. Gas chromatography/mass spectrometry and high‐performance liquid chromatography were used to evaluate 14 compounds, namely furfural, furfuryl alcohol, guaiacol, syringol, cis‐β‐methyl‐γ‐octalactone, 2‐phenylethanol, 4‐vinylguaiacol, benzyl alcohol, 2,3‐butanediol, γ‐butyrolactone, benzaldehyde, 4‐ethylguaiacol, gallic acid and ellagic acid. RESULTS: The microfungal treatments increased the concentration of some components. In particular, P. purpurogenum resulted in a significant improvement in the levels of guaiacol, furfural, syringol, furfuryl alcohol and 2‐phenylethanol. CONCLUSION: Penicillium purpurogenum and Ph. chrysosporium showed a constant trend (enrichment of furfural and benzaldehyde) independent to some extent of the medium used for chip treatment. Copyright © 2010 Society of Chemical Industry 相似文献