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Dark chocolate tablets were manufactured using 100% crystalline sucrose, 50% crystalline and 50% amorphous sucrose, and 100% amorphous sucrose. The physical state of sucrose was determined by differential scanning calorimetry (DSC) and X-ray diffraction. DSC scans of dark chocolate samples containing amorphous sucrose were characterized by a glass transition at 63 degrees C, a sucrose crystallization peak at 105 degrees C, and a melting endotherm at 188 degrees C. Independent of the amount of amorphous or crystalline sucrose used for the preparation of dark chocolate, all final chocolate products provided a single melting endotherm at 188 degrees C and a crystalline X-ray diffraction pattern. These results indicated that sucrose crystallized during production of dark chocolate and that no amorphous sucrose was present in the final chocolate products. 相似文献
13.
Velasco J Marmesat S Berdeaux O Márquez-Ruiz G Dobarganes C 《Journal of agricultural and food chemistry》2005,53(10):4006-4011
Major short-chain glycerol-bound compounds were investigated in olive oil (OO) and conventional sunflower oil (SO) during thermoxidation at 180 degrees C for 5, 10, and 15 h. These compounds included methyl heptanoate (C7:0), methyl octanoate (C8:0), methyl 8-oxo-octanoate (8-oxo-C8:0), methyl 9-oxononanoate (9-oxo-C9:0), dimethyl octanodiate (C8:0 diester), and dimethyl nonanodiate (C9:0 diester), which were analyzed by GC after derivatization of triacylglycerols to fatty acid methyl esters. An acceptable linear correlation (r = 0.967) was found between the total content of these compounds and the total content of polar compounds, suggesting that quantitation of the major short-chain glycerol-bound compounds provides a good indication of the total alteration level of oils heated at frying temperature. Samples with levels of polar compounds around 25% on oil showed total contents within 2-3 mg/g of oil. To determine the content of these compounds in used frying oils, 10 samples from restaurants and fried-food outlets in Spain were analyzed. Results showed total levels between 2.13 and 7.56 mg/g of oil in samples with contents of polar compounds ranging from 18.8 to 55.5% on oil. Samples with levels of polar compounds of approximately 25% showed total contents of the short-chain compounds similar to those found in the thermoxidized oils, that is, within 2-3 mg/g of oil. 相似文献
14.
Urbano G Aranda P Gómez-Villalva E Frejnagel S Porres JM Frías J Vidal-Valverde C López-Jurado M 《Journal of agricultural and food chemistry》2003,51(8):2415-2420
The effect of mild hydrothermal treatment and the addition of phytase under optimal conditions (pH 5.5, 37 degrees C) on the nutritive utilization of the protein of pea (Pisum sativum L.) flour was studied in growing rats by examining the chemical and biological balance. Mild hydrothermal treatment produced reductions of 83, 78, and 72%, respectively, in the levels of alpha-galactosides, phytic acid, and trypsin inhibitors and also produced a significant increase in the digestive utilization of protein. The additional fall in the levels of phytic acid caused by the addition of phytase did not lead to a subsequent improvement in the digestive utilization of protein. The mild hydrothermal treatment of pea flour produced a significant increase in the metabolic utilization of protein and carbohydrates, which was reflected in the protein efficiency ratio and food transformation growth indices. These effects were not observed in the phytase-supplemented pea diet. 相似文献
15.
A bull was referred for a progressive oligoasthenotheratozoospermia that resulted in a unsuitable seminal quality for the cryopreservation. Breeding soundness evaluation results suggested gonadal dysfunction. Because of the lack of normal ranges for these hormones in the bull, in this study, the hypogonadism and the site of the dysfunction (hypothalamus) were diagnosed by the gonadotropin-releasing hormone (GnRH) stimulation test. The evaluation of pituitary and testicular responsiveness by a GnRH stimulating test revealed a responsiveness of the pituitary and testis, thus a secondary hypogonadism (hypothalamic hypogonadism) was postulated and a therapeutic approach based on the subcutaneous administration of GnRH analog was attempted. An increase in semen volume, concentration and sperm characteristics were detected 9 weeks after the start of the treatment, corroborating the hypothalamic origin of the disease and the useful of the GnRH therapy. 相似文献
16.
Domenico Robbe Augusto Carluccio Alessia Gloria Alberto Contri Mario Ventura Claudia Rita Catacchio Paola Straticò Lucio Petrizzi 《Journal of Equine Veterinary Science》2012
A 4-day-old male Martina Franca donkey foal was evaluated for a forelimb alteration. Clinical examination and radiographs revealed the agenesia of the distal digit. Biochemical parameters were normal, and ultrasonographic evaluation did not identify any relievable organ alteration. Karyotype study revealed an abnormality on chromosome 1. The foal was discharged with a distal limb bandage in which a palmar splint was applied. A poor prognosis for the functionality of the limb was given. In endangered species, such as the Martina Franca donkey, the excessive inbreeding could result in an increase in genetic disorders. These findings shed new light on the possible pathogenesis of the digital dysgenesia. The study of the karyotype could be a useful approach to detect genetic alterations that could or could not be expressed in the animal, especially in endangered species in which a risk of an excessive inbreeding is considerable. These defects should be considered in the choice and selection of the breeders. 相似文献
17.
Dilda F Gioia G Pisani L Restelli L Lecchi C Albonico F Bronzo V Mortarino M Ceciliani F 《Veterinary journal (London, England : 1997)》2012,192(3):514-516
MicroRNAs (miRNAs) are a family of regulatory molecules involved in many physiological processes, including activation of cells of the immune system. This study investigated the effect of Escherichia coli lipopolysaccharide (LPS) and Staphylococcus aureus enterotoxin B (SEB) on the expression of five miRNAs involved in the inflammatory response, including miR-9, miR-125 b, miR-155, miR-146 a and miR-223, in bovine CD14(+) cells (monocytes). Incubation of monocytes with SEB induced down-regulation of miR-155, miR-223 and miR-125 b, but not the anti-inflammatory miRNA miR-146 a. Conversely, incubation with LPS upregulated both miR-155 and miR-146 a. In vitro incubation of isolated CD14(+) bovine monocytes with LPS and SEB elicited different and opposite expression of miRNAs reportedly involved in inflammatory reactions. 相似文献
18.
Gloria T Seaborn Theodore I J Smith Michael R Denson Abigail B Walker & David L Berlinsky 《Aquaculture Research》2009,40(6):656-668
Lipid content, lipid class and fatty acid compositions were determined in eggs from wild and captive black sea bass, Centropristis striata L., from northern (New England) and southern (South Carolina) regions to determine the effects of diet on egg composition and fertilization success. The formulated diets fed to the northern captive (NC) fish were higher in total lipids (22%) compared with the cut fish and squid diet fed to the southern fish (SC; 3.3% lipid) and had a higher relative amount of linoleic acid (LA) and lower relative amounts of docosahexaenoic acid (DHA) and arachidonic acid (AA). These dietary differences were broadly reflected in the egg lipid composition. The LA levels were higher in all lipid classes in eggs of NC fish while AA levels were lower. The DHA was higher in the major polar lipids (PL) (phosphatidylcholine and phosphatidylethanolamine) of SC eggs compared with NC. Compared with wild fish, both captive groups produced eggs with PLs richer in LA and lower in DHA and AA. Over all fish groups, fertilization success was directly correlated with levels of DHA and AA in the PLs and was inversely correlated with LA levels. 相似文献
19.
Alessio Bonaldo Gloria Isani Ramon Fontanillas Luca Parma Ester Grilli Pier Paolo Gatta 《Aquaculture International》2010,18(5):909-919
Three isoproteic (47% protein) diets were formulated to contain graded levels of crude fat (diet D16:16%, diet D24: 24% and
diet D32: 32%). Each diet was fed to satiation in three and to 80% satiation in two replicate groups of gilthead sea bream
(Sparus aurata), having an initial body weight of 72–74 g. The trial lasted 81 days. Groups fed to satiation showed higher final body weight
(FBW; 238.8–252.3 g vs. 218.0–229.3 g) and daily growth index (DGI; 2.49–2.65%/day vs. 2.27–2.34%/day) than those fed to 80%
satiation. Feed intake was significantly different both for feeding level and for diet composition. Fish fed to satiation
had higher feed conversion rate (FCR) compared to the 80% satiation groups (1.33–1.44 vs. 1.13–1.17; P ≤ 0.001). Within satiation groups, FCR was significantly lower in fish fed D16 compared to fish fed D32 (1.33 vs. 1.44, P ≤ 0.05), whereas no statistical differences were found within the 80% satiation groups. The increase in dietary lipid level
did not improve growth performance, feed efficiency and protein utilization but decreased gross lipid efficiency. Conversely,
a reduction in ration from satiation to 80% satiation decreased DGI, thus improving FCR. Feed costs were influenced by dietary
energy level and feeding ratio, the lowest energy diet at 80% satiation being the most profitable combination among the variables. 相似文献