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G Muscle (g + muscle)
Selected AbstractsRapid Vasodilation in Isolated Skeletal Muscle Arterioles: Impact of Branch OrderMICROCIRCULATION, Issue 2 2010BRUNO T. ROSEGUINI Microcirculation (2010) 17, 1,11. doi: 10.1111/j.1549-8719.2009.00005.x Abstract We tested the hypothesis that segmental differences in the responsiveness and time course of vasodilation to metabolic signals putatively involved in rapid onset vasodilation (ROV) at the start of exercise exist within the skeletal muscle vasculature. Cannulated first-order (1As) and third-order arterioles (3As) of the rat gastrocnemius (G) muscle were exposed to cumulative doses of KCl, acetylcholine (Ach), or adenosine (Ado). In addition, time course and magnitude of vasodilation to localized application of these agonists were determined. 1As and 3As dilated similarly to incremental doses of the agonists. Continuous monitoring of internal diameter revealed a fast and transient dilatory response to microinjections of the agonists, with an average time delay (TD) before the onset of vasodilation of 2.8 ± 0.2 seconds (1As: 3.0 ± 0.3 seconds and 3As: 2.6 ± 0.3 seconds) and time-to-peak (TP) of 8.2 ± 0.7 seconds (1As: 10.3 ± 1 seconds and 3As:5.7 ± 0.5 seconds). No significant differences were detected for all parameters between 1As and 3As for KCl or Ado application, while 1As had a significantly longer TP and greater peak dilation than 3As to Ach. These findings demonstrate that 1As and 3As from the rat G muscle appear to have similar responsiveness to vasoactive agonists. Furthermore, the average TD before vasodilation supports a role for metabolic signals as contributors to the ROV. [source] The effects of soluble gas stabilisation on the quality of packed sardine fillets (Sardina pilchardus) stored in air, VP and MAPINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 11 2008Rogério Mendes Summary Sardine (Sardina pilchardus) is a species that for its abundance assumes great importance in the Portuguese fishing sector. In order to contribute for a better utilisation of this species, the aim of this study was to investigate the effect of the pre-treatment with soluble gas stabilisation (SGS) (100% CO2 at 2 bar, during 15 and 30 min) on the quality and shelf-life of sardine fillets, packed in air (AP), vacuum (VP) and modified atmosphere (MAP: 5% O2/35% CO2/60% N2). During the chilled storage, the quality changes were evaluated by sensory evaluation, chemical and microbiological analysis. The total volatile basic nitrogen content remained almost constant, between 16 and 19 mg N/100 g muscle, during the storage period, for all samples. The TBARs values increased with storage time, for all batches and storage conditions. The application of SGS treatment to sardine fillets, resulted in a bacteriostatic effect, contributing to the improvement of the microbiological quality of fillets. Considering a sensory criteria, the shelf-life of SGS pre-treated sardine fillets was found to be 5 days in AP and MAP while in VP-treated fillets a shelf-life of 8 days was reported. At sensory rejection, sardine fillets presented a K -value of 30% in AP and MAP batches and 40% in VP batch. [source] BACTERIAL FORMATION OF HISTAMINE IN JACK MACKEREL (TRACHURUS SYMMETRICUS)JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2004A. BERMEJO ABSTRACT Peak histamine concentrations of 0.023, 0.031 and 0.027 g histamine/100 g muscle and maximal bacteria concentrations of 1.75, 1.59 and 0.423 g dry cells/100 g muscle were observed in muscles of jack mackerel stored at 25, 15 and 5C, respectively. Incubated fish homogenates suggest rate and transport limitations in histamine formation in muscle. The Mulchandani model predicted bacterial growth in muscle. The Luedeking and Piret expression fitted histamine formation in muscle; , values were 3.0 × 10,3, 1.23 × 10,2 and 4.17 × 10,2 g histamine/g dry cells, while ,-values were 4.5 × 104, 8.0 × 10,5 and 0 g histamine/g dry cells × h at 25, 15, and 5C, respectively. The model predicts that jack mackerel could be stored from 4.5 to 5.5 days in ice, from 1 to 2 days at 15C and from 17 h to 2 days at 25C before fishmeal quality might be affected. [source] Microbiological, chemical and sensory changes of whole and filleted Mediterranean aquacultured sea bass (Dicentrarchus labrax) stored in iceJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2003Dimitra Taliadourou Abstract The effect of filleting on the microbiological, chemical and sensory properties of aquacultured sea bass (Dicentrarchus labrax) stored in ice was studied. Pseudomonads, H2S-producing bacteria (including Shewanella putrefaciens) and Brochothrix thermosphacta were the dominant bacteria at the end of the 16 day storage period in ice for both whole ungutted and filleted sea bass. Enterobacteriaceae were also found in the spoilage microflora of whole ungutted and filleted sea bass, but their counts were always lower than those of pseudomonads, H2S-producing bacteria (including S putrefaciens) and B thermosphacta. Total viable counts for whole ungutted sea bass were always lower than those for filleted sea bass samples. Of the chemical indicators of spoilage, TMA (trimethylamine) values of whole ungutted sea bass increased very slowly, whereas significantly higher values were obtained for filleted samples, with respective values of 0.253 and 1.515 mg N per 100 g muscle being reached at the end of their shelf-life (days 13 and 9 respectively). TVB-N (total volatile basic nitrogen) values showed a slight increase for whole ungutted sea bass during storage, reaching a value of 26.77 mg N per 100 g muscle (day 13), whereas for filleted fish a corresponding value of 26.88 mg N per 100 g muscle was recorded (day 9). TBA (thiobarbituric acid) values increased slowly for whole ungutted and filleted sea bass samples throughout the entire storage period, reaching final values of 4.48 (day 13) and 13.84 (day 9) mg malonaldehyde kg,1 respectively. Sensory assessment of raw fish using the EC freshness scale gave a grade E for up to 5 days for whole ungutted sea bass, a grade A for a further 4 days and a grade B for an additional 4 days, after which sea bass was graded as C (unfit). Overall acceptability scores for odour, taste and texture of cooked whole ungutted and filleted sea bass decreased with increasing time of storage. The results of this study indicate that the shelf-life of sea bass stored in ice, as determined by overall acceptability sensory scores and microbiological data, is 8,9 days for filleted and 12,13 days for whole ungutted fish. Copyright © 2003 Society of Chemical Industry [source] Combination of bulk storage in controlled and modified atmospheres with modified atmosphere packaging system for chilled whole gutted hakeJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 6 2001Claudia Ruiz-Capillas Abstract Whole gutted hake placed in boxes of ice were kept in modified and controlled atmospheres for 12 days with the gas mixture 60%CO2/15%O2/25%N2 (v/v/v) at 2,±,1,°C. Each lot of hake was then subdivided into two other lots and these were packed on trays, some of them in air and some in the same mixture of gases. The trays were kept at 2,°C until spoilage. The shelf-life of the hake stored in these conditions was assessed by physical (pH), chemical (TVBN (total volatile basic nitrogen) and TMA-N (trimethylamine nitrogen)) and sensory (inspection and taste panel) analyses. The results of these analyses indicated that the control lot (stored in air throughout) was rejected before the lots kept in adjusted atmospheres. However, the taste panel accepted all the lots, including the control lot, after 24 days of storage. The sample which was kept at 2,°C in a controlled atmosphere for 12 days and then packed in a modified atmosphere of the same gas mixture did not exceed pH 7 after 31 days of storage, nor the limits of TVBN and TMA-N of 40 and 12,mg per 100,g respectively. As regards oxidative rancidity, TBA (2-thiobarbituric acid) levels were very low under all storage conditions and did not exceed 2.5,mg malonaldehyde per 100,g muscle. According to the results of this study, bulk storage of whole gutted hake in boxes in ice under a controlled atmosphere could be combined with later packaging in a modified atmosphere on trays stored at 2,°C to extend the shelf-life of the hake. © 2001 Society of Chemical Industry [source] | ||||||||||