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81.
Giuseppina Adiletta Loredana Liguori Donatella Albanese Paola Russo Marisa Di Matteo Alessio Crescitelli 《Food and Bioprocess Technology》2017,10(9):1631-1641
A preliminary characterization of two new soft-seeded pomegranate varieties (MR-100® and KINGDOM®) based on their main physico-chemical and nutritional parameters was reported. The two varieties showed significant differences (p ≤ 0.05) in polyphenols, anthocyanins and antioxidant activity. Kingdom pomegranate had higher polyphenols (2524.73 mg GAE/L), anthocyanins (752.49 mg C3gE/L) and antioxidant activity (EC50 13.58 μL/mL) than MR-100 (1792.74 mg GAE/L, 141.29 mg C3gE/L and EC50 47.53 μL/mL, respectively). Moreover, minimally processed arils of the two varieties were packaged in semipermeable and micro-perforated film at 5 °C, and the quality changes that occurred during storage condition (15 days) were investigated. During storage, Kingdom arils exhibited a better performance in terms of antioxidant activity, polyphenols and anthocyanin content with respect to MR-100. Furthermore, the packaging systems did not affect the estimated quality parameters for both varieties. Based on the sensory evaluation and microbial counts, both aril varieties reached, at 15-day storage, suitable values for commercial purpose. 相似文献
82.
Giuseppina Luzzi Marco Steffens Ingrid Clawin‐Rdecker Wolfgang Hoffmann Charles M A P Franz Jan Fritsche Peter Chr Lorenzen 《International Journal of Dairy Technology》2020,73(3):502-512
Lactose solutions of up to 50% (w/v) were incubated with lactases and glucose isomerases for subsequent implementation in dairy product samples to enhance sweetness. A degree of hydrolysis of >90% and of isomerisation of 50% were attainable. The sensory sweetening power of lactose in solutions of up to 50% (w/v) can be enhanced 2–3 times. Based on sensory experiments, application of this bi‐enzymatic system in yoghurt and pudding samples allowed for a 10–20% (w/w) reduction in the total sugar content, whilst retaining equal sweetness. The growth of yoghurt starter cultures was not affected, yet furosine formation more than doubled in high heated, enzyme‐modified milk. 相似文献
83.
Francisco?Wendel?B.?Aquino Sueli?RodriguesEmail author Ronaldo?F.?Nascimento Ant?nio?Renato?S.?Casimiro 《European Food Research and Technology》2005,221(6):739-745
In response to the increasing demand for aged distilled spirits, wood extracts have been investigated as accelerating agents
in distilled spirits. The aim of this work was to obtain and to evaluate the potential use of Amburana cearensis powder extracts as an accelerating aging agent in sugar cane distilled spirits. Wood powder was submitted to different toasting
treatments using conventional drying oven and microwave oven. Instead of using the traditional reflux extraction method, the
phenolic compounds were extracted by means of ultrasonic treatment using a 50% ethanolic solution with pH adjusted to 4.5.
The concentration of gallic acid, 5-hydroxymethylfurfural, furfural, vanillic acid, syringic acid, vanillin, coniferaldehyde,
sinapaldehyde and coumarin, determined by high performance liquid chromatography (HPLC) were used as quality parameters of
powder toasting treatment and ethanolic extraction. The use of toasted wood powder combined with ultrasonic extraction showed
higher yields when compared to the traditional solvent extraction method when obtaining wood extracts. The extraction method
presented in this work is also less time consuming. 相似文献
84.
The objectives were to estimate the effects of various environmental factors on female calf survival of Israeli Holsteins, to estimate the economic value of calf survival under Israeli conditions, to estimate the genetic and environmental variance components for calf and cow survival using the individual animal model, to perform GWAS analyses of survival to first calving and herd life after first calving, to estimate the genetic and environmental trends for calf survival since 1985, to estimate genetic correlations of calf survival with the traits included in the current Israeli breeding index, and to estimate the consequences of inclusion of calf survival in the national selection index. Mean calf survival rate of Israeli Holsteins from 2001 through 2008 was 0.85, and the mean economic value of survival to first calving was $526. Birth month, gestation length, dystocia, and twin birth significantly affected calf survival rate. Dystocia and twin birth each reduced survival rate by 0.034. Survival rate was highest for calves born in October and lowest for calves born in February. The difference between these months was 3.4%. Maximum survival was at a gestation length of 276 d, the mean gestation length for this population. Survival rate was reduced to 0.76 for calves born after a gestation length of 260 d. The individual animal model was applied for all the genetic analyses. Heritability for calf survival to first calving, as estimated by REML, was 0.009, whereas heritability of herd life from first calving was 0.15. The complete data set for genetic analysis of survival to first calving included 1,235,815 calves born between 1985 and 2017. Annual genetic and phenotypic trends for calf survival were 0.019 and 0.015%, respectively. Correlations of transmitting abilities of 226 sires born since 2010 for calf survival with the traits included in the Israeli breeding index were significant only for the maternal effects of dystocia and stillbirth. The GWAS analysis was based on the transmitting abilities of 1,493 bulls with genotypes and reliabilities >0.5 for calf survival and cow herd life. There were 7 single nucleotide polymorphisms with coefficients of determination >0.03 for calf survival and 12 single nucleotide polymorphisms with coefficients of determination >0.05 for cow survival. There was no overlap between the genome-wide significant markers for the GWAS analyses of calf survival and cow herd life. This corresponds to the conclusion from the REML results and the low correlations between the sire evaluations that the genetic control of the 2 traits are not similar. Inclusion of calf survival in the Israeli breeding would result in a 0.5% increase in calf survival over 10 yr but reduce progress for the other traits by 8%. 相似文献
85.
Natalia Brossard Beatriz Gonzalez-Muñoz Carolina Pavez Arianna Ricci Xinmiao Wang Fernando Osorio Edmundo Bordeu Giuseppina Paola Parpinello Jianshe Chen 《International Journal of Food Science & Technology》2021,56(10):5382-5394
Astringency is a sensory attribute, related to the quality and mouthfeel of red wines. However, the origin of astringency sub-qualities, such as the typical drying astringency found in immature grapes, is still unknown. Astringency of red wines with similar tannin content but different astringency sub-qualities, from different harvest dates, is studied. Astringency was characterised in terms of friction coefficient, polyphenol content, sensory analysis and tannin/salivary–proteins aggregates characterisation. A different evolution during ripening was found for both Cabernet Sauvignon and Carménère, and tannin–protein aggregates showed differences in size, shape and surface. The velvety sub-quality appears to be related to aggregates with low precipitation, and with specific surface characteristics as roundness and Feret diameter. Results from this work propose an effect of aggregates on sensory perception and opens the possibility to explore their effect on oral lubrication. 相似文献
86.
Incidences of ketosis, metritis, mastitis, and retained placenta were studied in Israeli Holstein cows calving between 2008 and 2017. These diseases were selected based on their economic impact. Ketosis, metritis, and retained placenta were scored dichotomously. Mastitis was scored as absent, a single occurrence during the lactation, or more than 1 occurrence. Ketosis and metritis were recorded during the first 21 d after calving, retained placenta during the first 5 d after calving, and mastitis up to 305 d in milk. The effects of herd-year-season, calving age, month of calving, gestation length, and occurrence of dystocia were included in the first-parity analysis models. All effects were significant for metritis and retained placenta. For ketosis, all effects were significant, except for gestation length. For mastitis, only the effects of herd-year-season and calving age were significant. Variance components were computed by the multitrait animal model. The 4 diseases were analyzed jointly based on first-parity records, and each disease was analyzed separately for parities 1 to 3 with the different parities considered separate traits. The 4 disease traits in first parity were also analyzed jointly with the 6 major traits included in the Israeli breeding index: milk, fat, and protein production; somatic cell score; female fertility; and longevity. Heritability was highest for metritis and lowest for mastitis, but all heritabilities were <0.07, similar to previous studies. For all 4 diseases, genetic correlations among the first 3 parities were >0.65, and all residual correlations were <0.07. Selection of herd-years assumed to have more accurate recording of mastitis did not result in higher heritability estimates. Genetic correlations between the disease traits and milk, fat, and protein production were economically unfavorable, while correlations between the disease traits and somatic cell score, female fertility, and longevity were economically favorable. Expected genetic changes in the disease traits after 10 yr of selection with the current Israeli breeding index were all <1%, except for ketosis, which was predicted to increase by 1.5%. Inclusion of these traits in a proposed index with the disease traits constituting 7% of the index would result in only marginal improvements for the disease traits and adversely affect genetic gain for fat and protein production. Thus, inclusion of these traits in the breeding index cannot be justified economically. 相似文献
87.
Amplitude modulated instability in reactants plenum of a rotating detonation combustor 总被引:1,自引:0,他引:1
Vijay Anand Andrew St. George Ephraim Gutmark 《International Journal of Hydrogen Energy》2017,42(17):12629-12644
The pronounced interest in rotating detonation combustors (RDC) in recent years has witnessed the investigation of multiple facets of the combustor, like reactants, injection schemes and combustor geometry. The issue of instabilities in RDCs is a nascent field, and requires both the identification, and the subsequent explanation of different instability mechanisms. In particular, we are concerned with the low frequency instability exhibited by the detonation wave. This is attributed to two different types of low frequency instabilities—amplitude and frequency modulated—that are discovered in the air plenum of an RDC, and subsequently discussed. The occurrence of these instabilities is observed to depend on the fuel injection scheme used and the air flow rates through the combustor. The amplitude modulated instability in the air inlet is spatially varying, and rotates in a direction opposite to the direction of the detonation wave. At higher air flow rates, and thus higher pressure ratios across the air injection, this instability disappears. A preliminary hypothesis is proposed to explain this amplitude modulation. 相似文献
88.
Didier Dupont Giuseppina Mandalari Daniel Mollé Julien Jardin Odile Rolet‐Répécaud Gabriel Duboz Joëlle Léonil Clare E. N. Mills Alan R. Mackie 《Molecular nutrition & food research》2010,54(11):1677-1689
The objective of this study was to determine whether processing could modify the resistance of casein (CN) to digestion in infants. A range of different dairy matrices was manufactured from raw milk in a pilot plant and subjected to in vitro digestion using an infant gut model. Digestion products were identified using MS and immunochemical techniques. Results obtained showed that CNs were able to resist digestion, particularly κ‐ and αs2‐CN. Resistant areas were identified and corresponded to fragments hydrophobic at pH 3.0 (gastric conditions) and/or carrying post‐translational modifications (phosphorylation and glycosylation). Milk processing led to differences in peptide patterns and heat treatment of milk tended to increase the number of peptides found in digested samples. This highlights the likely impact of milk processing on the allergenic potential of CNs. 相似文献
89.
Iole Pitino Cinzia Lucia Randazzo Giuseppina Mandalari Alberto Lo Curto Richard Martin Faulks Yvan Le Marc Carlo Bisignano Cinzia Caggia Martin Sean John Wickham 《Food microbiology》2010
In the present study six probiotic Lactobacillus rhamnosus strains were investigated for their ability to survive in the human upper gastrointestinal tract through a dynamic gastric model of digestion. MRS broth was used as delivery vehicle and survival was investigated during in vitro gastric and gastric plus duodenal digestion. Results highlighted that all tested strains showed good survival rate during both gastric and duodenal digestion. In particular, three strains exhibited a great survival showing a recovery percentage in the range between 117 and 276%. In agreement with survival data, high lactic acid production was detected for all strains, confirming their metabolic activity during digestion. 相似文献
90.
Giuseppina Rea Amina AntonacciMaya Lambreva Sandro PastorelliArianna Tibuzzi Simone FerrariDirk Fischer Udo JohanningmeierWieslaw Oleszek Teresa DoroszewskaAngela Maria Rizzo Patrizia V.R. BerselliBruno Berra Alessandra BertoliLuisa Pistelli Barbara RuffoniCarole Calas-Blanchard Jean Louis MartySimona Carmen Litescu Mirela DiaconuEleftherios Touloupakis Demetrios GhanotakisMaria Teresa Giardi 《Trends in Food Science & Technology》2011,22(7):353-366