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Stability of gamma-glutamyltransferase activity in calf sera after refrigerated or frozen storage.
1997
Muller F. | Tyler J.W. | Parish S.M. | Johnson K.A. | Krytenberg D.S. | Wilson L.K.
Histamine content in rennet ripening cheeses during storage at different temperatures and times
2018
Madejska, Anna | Michalski, Mirosław | Pawul-Gruba, Marzena | Osek, Jacek
In recent years, there has been a great interest in biogenic amines such histamine, as they are associated with the quality and safety of some kinds of fermented foods. The aim of this study was to evaluate the effect of temperature and storage time on the content of histamine in cheeses. Samples of mould and hard cheeses were examined with RP-HPLC with an organic-aqueous mobile phase containing acidic buffer and chaotropic salt. The samples were stored either at 22 ± 2°C for 42 days (mould and hard cheeses) or at 4 ± 2°C for 112 days (mould cheeses) and 133 days (hard cheeses). The mean total histamine content in cheeses stored at 22°C was higher than the content in those stored at 4°C, with the highest concentrations found in Gorgonzola Piccante cheese (730.47 mg/kg). Histamine concentration in some types of cheeses exceeded the toxic threshold dose, indicating that after long or inadequately cool storage they may not be safe for consumers. To protect cheeses from contamination with histamine-producing bacteria and to safeguard consumers from poisoning, factors conducive to this amine’s formation should be minimised during cheese processing. Suitable temperature and time during storage of cheeses are recommended to avoid the intoxication. Monitoring of this toxin in food is necessary to ensure safety of consumers.
Mostrar más [+] Menos [-]Effect of Lysozyme Treatment on Quality and Bacterial Contamination of Chilled Chicken Legs
2013
Kijowski Jacek | Marciszewska Celina | Cegielska-Radziejewska Renata | Popiół Anna
The effect of spraying lysozyme solutions of varying activity on microbiological stability and organoleptic features of chicken legs with skin was investigated. Lysozyme was applied at concentrations ranging from 3,000 to 48,000 U/mL. The effect of storage time at 4oC on the total aerobic bacterial count, coli titre, occurrence of enterococci, anaerobic spore forming bacilli, and pathogenic staphylococci was analysed along with the examination of sensory quality attributes. The investigations showed that the addition of lysozyme resulted in a considerable inhibition of growth of the initial aerobic bacterial counts and a limitation of disadvantageous organoleptic changes during cold storage of the legs. The lysozyme solution with the activity of 48,000 U/mL caused a 20-fold reduction in the initial aerobic bacterial count. Sensory examination showed that samples subjected to the action of lysozyme and stored for 120 h under cold storage conditions did not differ qualitatively from fresh legs. The obtained results revealed that lysozyme might be an effective agent extending shelf-life of portioned poultry meat.
Mostrar más [+] Menos [-]Collection and characterization of semen from green iguanas (Iguana iguana)
2013
Zimmermann, Dawn M. | Mitchell, Mark A. | Perry, Brittany Heggem
Objective—To determine an efficient method for the collection of semen samples by means of electroejaculation, characterize spermatozoa quality and quantity, and determine the effect of refrigerated storage on motility of spermatozoa obtained from green iguanas (Iguana iguana). Animals—18 adult green iguanas. Procedures—Green iguanas were anesthetized, and semen samples were obtained by means of electroejaculation. Up to 3 series of electrostimulations were performed; the procedure was stopped after a semen sample was obtained. Various semen sample variables were evaluated. Results—Semen samples were obtained from 16 iguanas; most (n = 10) iguanas produced a semen sample after the second series of electrostimulations. Median semen sample volume was 0.05 mL. Mean spermatozoa concentration was 2 69.0 × 10(6) spermatozoa/mL. Median percentage of motile spermatozoa was 78%. The only morphological abnormality of spermatozoa was bent tails (mean percentage in a semen sample, 5.7%). Spermatozoa motility decreased significantly during refrigeration (4°C); median percentage motility after 24, 48, and 72 hours of refrigeration was 60%, 33%, and 0%, respectively. Conclusions and Clinical Relevance—Results of this study suggested electroejaculation can be performed to collect semen samples from green iguanas, characteristics of iguana semen samples are similar to those for semen samples obtained from other reptiles, and motility of iguana spermatozoa decreases during refrigeration within 48 to 72 hours.
Mostrar más [+] Menos [-]Effects of storage on serum ionized calcium and pH values in clinically normal dogs
1995
Schenck, P.A. | Chew, D.J. | Brooks, C.L.
The stability of ionized calcium (CaI) concentration and pH in sera (n = 14) stored at 23 or 4 C for 6, 9, 12, 24, 48, or 72 hours, or -10 C for 1, 3, 7, 14, or 30 days was evaluated. Also studied were the effects of oxygen exposure, cold handling, and feeding on CaI and pH values. Results indicated that serum CaI concentration was stable throughout 72 hours of storage at 23 or 4 C, and for 7 days at -10 C. Serum CaI concentration significantly (P < 0.05) decreased by 14 days of storage at -10 C. Serum pH was stable for 6 hours at 23 or 4 C, and for 24 hours at -10 C, but significantly (P < 0.05) increased by 9 hours of storage at 23 or 4 C and by 3 days at -10 C. Exposure of the surface of the serum to air immediately before measurement had no effect on CaI or pH values, but mixing serum with air resulted in significantly (P < 0.05) decreased CaI concentration and increased pH. Handling of blood on ice resulted in significantly (P < 0.05) higher serum pH, compared with blood handled at 23 C, but serum CaI concentration was unaffected. Serum obtained at 2 hours after feeding did not have any significant changes in CaI, total calcium, or pH values. It appears that if canine serum is obtained, handled, and stored anaerobically, CaI concentration can be accurately measured after 72 hours at 23 or 4 C, or after 7 days at -10 C.
Mostrar más [+] Menos [-]Effects of refrigerated storage on hemostatic stability of four canine plasma products
2020
Edward, Thomas H. | Meledeo, Michael A. | Peltier, Grantham C. | Ruiz, Daikor D. | Henderson, Alice F. | Travieso, Stephanie | Pusateri, Anthony E.
OBJECTIVE To assess clotting times, coagulation factor activities, sterility, and thromboelastographic parameters of liquid plasma (LP), thawed fresh frozen plasma (FFP-T), and 2 novel formulations of freeze-dried plasma (FDP) stored refrigerated over 35 days. SAMPLE 6 units of canine LP and FFP-T from a commercial animal blood bank and 5 units each of 2 formulations of canine FDP. PROCEDURES Prothrombin time; activated partial thromboplastin time; activities of coagulation factors II, V, VII, VIII, IX, X, XI, and XII; and thromboelastographic parameters were determined for each product on days 0 (baseline), 3, 7, 14, 21, 28, and 35. For each day, a sample of each product was also submitted for aerobic bacterial culture. RESULTS Small changes in coagulation factor activities and mild increased time to initial clot formation in LP and FFP-T were noted over the 35-day storage period. Activities of factor VIII in FDP1 and factor XII in FDP2 were < 50% at baseline but varied throughout. Compared with FFP-T, time to initial clot formation was increased and clot strength was preserved or increased for the FDPs throughout the study. One FDP had decreased pH, compared with other products. No plasma product yielded bacterial growth. CONCLUSIONS AND CLINICAL RELEVANCE Liquid plasma and FFP-T would be reasonable to use when stored refrigerated for up to 35 days. Both FDP products showed variability in coagulation factor activities. Studies investigating the usefulness of these plasma products (FDPs) in dogs and the variable days of refrigerated storage (all products) are warranted.
Mostrar más [+] Menos [-]Effect of cold storage on immediate graft function in an experimental model of renal transplantation in cats
2017
Csomos, Rebecca A. | Hardie, Robert J. | Schmiedt, Chad W. | Delaney, Fern A. | McAnulty, Jonathan F.
OBJECTIVE To assess the effect of cold storage (CS) on immediate posttransplantation function of renal autografts in cats. ANIMALS 15 healthy 1-year-old cats. PROCEDURES Cats were assigned to 2 groups and underwent autotransplantation of the left kidney followed by nephrectomy of the right kidney. The left kidney was autotransplanted either immediately (IT group; n = 6) or after being flushed with a cold sucrose phosphate solution and stored on ice while the implant site was prepared (CS group; 9). Serum creatinine and BUN concentrations were monitored daily and autografts were ultrasonographically examined intermittently for 14 days after surgery. RESULTS Mean duration of CS was 24 minutes for the CS group. Posttransplantation serum creatinine and BUN concentrations for the CS group had lower peak values, returned to the respective reference ranges quicker, and were generally significantly lower than those for the IT group. Mean posttransplantation autograft size for the CS group was smaller than that for the IT group. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that immediate posttransplantation function of renal autografts following a short period of CS was better than that of renal autografts that did not undergo CS, which suggested CS protected grafts from ischemic injury and may decrease perioperative complications, speed recovery, and improve the long-term outcome for cats with renal transplants. IMPACT FOR HUMAN MEDICINE Cats metabolize immunosuppressive drugs in a manner similar to humans; therefore, renal transplantation in cats may serve as a desirable model for investigating the effects of renal transplantation in human patients.
Mostrar más [+] Menos [-]Effect of sample handling on measurement of plasma glucose and blood lactate concentrations in horses before and after exercise
1994
Ferrante, P.L. | Kronfeld, D.S.
Collection of a satisfactory blood sample requires special procedures to prevent changes in glucose and lactate content after the sample has been obtained. Changes in measured plasma glucose and blood lactate concentrations attributable to anticoagulants and storage procedures, respectively, were examined in blood samples obtained from horses at rest and after exercise. To evaluate the effect of anticoagulants on measured plasma glucose concentration, blood was preserved with either sodium fluoride/potassium oxalate or lithium heparin. Measured plasma glucose concentration in blood obtained at rest and after exercise was 6 and 10% lower (P = 0.0038), respectively, when blood was preserved with fluoride/oxalate, compared with heparin. The erythrocyte volume in the blood sample was 15% smaller (P = 0.0001) in samples preserved with fluoride/oxalate, indicating a movement of water out of erythrocytes in the blood sample mixed with that anticoagulant. To evaluate the effect of storage procedure on measured blood lactate concentration, part of the blood sample was immediately deproteinized for blood lactate analysis, and the remaining blood was maintained for 30 and 60 minutes at either 0 or 22 C before deproteinization. When blood samples were maintained at 0 C prior to deproteinization, there was no difference in blood lactate concentration, regardless of the incubation time, compared with that in samples immediately deproteinized. Blood lactate concentration was greater (P < 0.01) in samples maintained at 22 C, compared with that in samples immediately deproteinized, and with that in equivalent samples maintained at 0 C. Blood preserved with fluoride/oxalate had lower measured plasma glucose concentration, compared with blood preserved with heparin, which was probably attributable to shrinkage of erythrocytes and dilution of the plasma with intracellular water. Minimal changes in blood lactate concentration were observed in samples maintained at 0 C up to 60 minutes.
Mostrar más [+] Menos [-]The effect of jicama (Pachyrhizus erosus L.) starch on the properties and probiotic potential of L. plantarum SN13T fermented milk
2024
Sri Melia | Indri Juliyarsi | Rizki D. Setiawan | Salam N. Aritonang | Hurriya Alzahrah | Doni Supandil
Objective: This study investigated the application of Jicama starch (Pachyrhizus erosus L.) as a stabilizing agent to enhance the longevity and integrity of fermented milk. Materials and Methods: Lactobacillus plantarum SN13T (6 gm/100 ml) and Jicama starch (2 gm/100 ml) were added into pasteurized milk (65°C, 30 min) and then incubated under anaerobic conditions at 37°C for 18 h. The fermented milk was stored at 4°C. The evaluation on proximate composition, pH, titratable acidity (TA), viscosity, water holding capacity (WHC), syneresis, total lactic acid bacteria (LAB), and hedonic sensory evaluation was conducted at 1, 7, 14, 21, and 28 days of storage. Results: Throughout the storage period, fermented milk enriched with Jicama starch significantly (p < 0.05) increased pH, TA, population dynamics of LAB, viscosity, WHC, and syneresis. It effectively sustained WHC and mitigated syneresis, thus ensuring the preservation of vital product quality. Furthermore, the quantity of LAB within the fermented milk consistently met the pro¬biotic threshold of 84.50 × 108 CFU/ml. The hedonic sensory evaluation results indicated that fermented milk showed consistent sensory attributes throughout storage, except for overall acceptance, which declined on day 28. Conclusion: The addition of Jicama starch revealed a promising health probiotic product, presenting a viable avenue for delivering probiotic benefits to consumers while maintaining the palatabil¬ity and efficacy of the product. [J Adv Vet Anim Res 2024; 11(2.000): 317-322]
Mostrar más [+] Menos [-]The shelf life of buffalo meat marinated with pomegranate (Punica granatum) peel extract
2021
Nur Rasuli | Valentinus Priyo Bintoro | Agung Purnomoadi | Nurwantoro Nurwantoro
Objective: The purpose of this study was to investigate how pomegranate peel extract (PPE) can prevent lipid oxidation, peroxide value, and pathogenic bacteria growth in buffalo meat. Materials and Methods: PPE and buffalo meat were employed in this investigation. The buffalo meat marinated with PPE was evaluated by refrigerating it at a temperature of 5°C ± 1°C on days 0, 4, 8, 12, and 16. PPE was added to buffalo meat at a rate of 0% as a control (K0), 0.50% (K1), 1.00% (K2), 1.50% (K3), and 2.00% (K4). Results: The addition of PPE lowered the total plate count, peroxide value, lipid, and pH between treatments and storage period (p < 0.05). PPEs high concentration of polyphenols, flavonoids, antioxidants, and antibacterial substances may decrease lipid oxidation, peroxide production, and bacterial growth rate. Conclusions: Marinating buffalo meat in PPE may help maintain the meats freshness while being stored at a refrigerator temperature (5°C ± 1°C). [J Adv Vet Anim Res 2021; 8(4.000): 612-618]
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