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1.
The aim of this work was to investigate the use of rainbow trout (Oncorhynchus mykiss) in ready to eat döner kebab production and determine the effects of marination, cooking and storage conditions (4 and ?18 °C) on physico-chemical and microbiological properties of döner kebab. The raw trout meat, raw, cooked and stored döner kebab samples were subjected to moisture, protein, fat, ash, color, pH, cholesterol, biogenic amines, lipid oxidation, fatty acids profile, texture, microbiological and sensory analysis. The results indicated that the major fatty acids in trout döner kebab were palmitic, stearic, oleic, omega-3 and omega-6 fatty acids and unsaturated fatty acids were higher than saturated fatty acids (p < 0.05). Low biogenic amine and cholesterol contents were determined in döner kebab. It was found that ?18 °C of storage temperature was more effective than 4 °C for inhibition of lipid oxidation and microbial growth in trout döner kebab (p < 0.05). While cooking affected parameters evaluated (p < 0.05), marination did not have any significant effect. The study results indicated that using rainbow trout meat in döner kebab production could be beneficial to provide healthy meat products without posing any acceptability problems in terms of quality factors. This is the first paper to be reported on physico-chemical and microbiological properties of döner kebab produced with rainbow trout and effects of marination, cooking and different storage temperatures on these physico-chemical and microbiological properties.  相似文献   

2.
Changes of meat shear force and its characteristics during cooking have been extensively studied, but great variability existed due to the cooking method among different studies. This study was designed to focus on the dynamic changes of beef intramuscular connective tissue (IMCT) and muscle fiber during water-bath heating and their effects on beef shear force. At 4 d postmortem, beef semitendinosus muscles were divided into 11 steaks and then cooked respectively to an internal temperature of 40, 50, 55, 60, 65, 70, 75, 80, 85, and 90°C (the remainder was not cooked as control). Collagen content and its solubility, transition temperature of perimysia and endomysia, fiber diameter, and Warner–Bratzler shear force values (WBSF) were determined. The results showed that fiber diameter decreased gradually during cooking, concomitant with the increases in filtering residue and WBSF. The maximum transition temperature (T max) of endomysial components was lower than that of perimysial components (50.2 vs. 65.2°C). Muscle fiber and IMCT (especially perimysia) shrank during cooking, resulting in the increase of WBSF when the internal temperature was lower than 75°C, but further cooking led to the disintegration of perimysial structure, lowing up the increase of WBSF between 75 and 90°C. For beef semitendinosus muscle, the internal temperature of 65°C is a critical cooking point where meat gets tougher.  相似文献   

3.
Effects of 0.5% encapsulated (e) phosphates (sodium tripolyphosphate, STP; sodium hexametaphosphate, HMP; sodium pyrophosphate, SPP) on lipid oxidation during storage (0, 1, and 7 d) of ground meat (chicken, beef) after being cooked to 3 end‐point cooking temperatures (EPCT; 71, 74, and 77 °C) were evaluated. The use of STP or eSTP resulted in lower (P < 0.05) cooking loss (CL) compared to encapsulated or unencapsulated forms of HMP and SPP. Increasing EPCT led to a significant increase in CL (P < 0.05). Both STP and eSTP increased pH, whereas SPP and eSPP decreased pH (P < 0.05). The higher orthophosphate (OP) was obtained with STP or SPP compared to their encapsulated counterparts (P < 0.05). The lowest OP was determined in samples with HMP or eHMP (P < 0.05). A 77 °C EPCT resulted in lower OP in chicken compared to 74 and 71 °C (P < 0.05), dissimilar to beef, where EPCT did not affect OP. In encapsulated or unencapsulated form, using STP and SPP enhanced reduction in TBARS and lipid hydroperoxides (LPO) compared with HMP (P < 0.05). Regardless of the phosphate type, more effective lipid oxidation inhibition was achieved by the use of encapsulated forms (P < 0.05). Increasing EPCT resulted in lower TBARS in beef and higher LPO values in both beef and chicken samples (P < 0.05). Findings suggest that encapsulated phosphates can be a strategy to inhibit lipid oxidation for meat industry and the efficiency of encapsulated phosphates on lipid oxidation inhibition can be enhanced by lowering EPCT.  相似文献   

4.
The objective of this study was to investigate the effects of ohmic (OH) and water bath (WB) cooking on shear parameters, protein degradation and ultrastructure changes of porcine longissimus dorsi muscle at the same endpoint temperatures (EPTs; range, 20–100 °C). The cooking loss and Warner–Bratzler shear force of the OH-cooked meat were significantly lower (P?<?0.05) while protein solubility, pH and endothermic transition temperature were higher than those obtained by WB cooking at the same EPTs (range, 20–80 °C). Sodium dodecyl sulphate polyacrylamide gel electrophoresis analysis showed that during OH cooking, the meat had slightly fainter protein bands than that of WB-cooked ones. Less obvious shrinkage of the sarcomere and loss in the structure of Z discs were detected especially in OH-cooked meat at EPTs (100 °C). Strong correlations among pH, cooking loss, Warner–Bratzler shear force, sarcoplasmic protein solubility, T max2, and T max3 were observed in meat following OH cooking.  相似文献   

5.
The potential of rosemary (Rosmarinus officinalis L.) to inhibiting lipid oxidation in minced chicken breast and thigh muscle processed at 600 MPa for 10 min during subsequent heat treatment was investigated using electron spin resonance (ESR) spectroscopy and electrochemical detection of oxygen consumption. Chicken breast cooked at 95 °C was found to have significantly higher rate of formation of free radicals and oxygen consumption rate than the samples cooked at 70 °C and 120 °C and this intermediate cooking temperature was used to evaluate the effect of pressure on oxidation during subsequent cooking. Rosemary was found effective in retarding lipid oxidation since the pressurized, minced chicken breast and thigh with rosemary added showed lower rate of oxygen consumption and lower tendency of free radical formation following heat treatment than the samples without rosemary. Pressurized chicken thigh showed a higher susceptibility to oxidation than chicken breast upon subsequent heat treatment. Oxidation in pressurized and subsequently heat-treated chicken breast was from a higher tendency of radical formation concluded to be in an earlier phase of oxidation compared to thigh subjected to the same treatment.Industrial relevanceHigh-pressure processing has a great potential for microbial control of raw chicken meat as a “fresh” chill-stored, convenience product for wok cooking. While raw chicken meat is oxidatively stable, high-pressure treatment at 600 MPa and above induces lipid oxidation resulting in off-flavors during subsequent cooking. Addition of 0.1% dried rosemary to minced chicken thighs or breasts prior to high-pressure processing inhibit lipid oxidation during subsequent cooking and could form the basis for product development.  相似文献   

6.
This study investigated the influence of replacing One-humped camel meat instead of cow meat (0, 25, 50, 75 and 100 %) on quality characteristics and frozen storage stability in burgers. For this purpose thiobarbituric acid test (TBA-RS), cooking characteristics, color parameters, texture and sensory properties were studied during 3 months at ?18 °C. Significant differences (p < 0.05) were observed in the moisture retention, diameter reduction, sensory properties, lightness, yellowness and springiness. Cooking yield, TBA-RS, fat retention, cohesiveness, flavor and texture showed significant differences (p < 0.05) through storage. Other evaluated properties of burgers showed no significant differences (p > 0.05) in various levels of camel meat and over storage term. Moisture retention of burgers increased with increasing of camel meat content. The sensory panel scores for flavor, texture, juiciness and overall acceptability increased but color scores decreased with increasing the level of camel meat. Cooking yield, fat retention and cohesiveness decreased by increasing the storage period.  相似文献   

7.
Thermal inactivation of a four-strain mixture of E. coli O157:H7 was determined in lean ground turkey, lamb and pork. Inoculated meat was packaged in bags completely immersed in a circulating water bath and held at 55, 57.5, 60, 62.5, and 65°C for predetermined lengths of time. The surviving cell population was enumerated by spiral plating meat samples on tryptic soy agar overlaid with Sorbitol MacConkey agar. D-values, determined by linear regression, in turkey were 11.51, 3.59, 1.89, 0.81 and 0.29 min at 55, 57.5, 60, 62.5 and 65°C, respectively (z=6.5°C). When a survival model was fitted to the non-linear survival curves, D-values in turkey ranged from 11.26 min at 55°C to 0.23 min at 65°C (z=6°C). When the E. coli O157:H7 four-strain cocktail was heated in ground pork or lamb, D-values calculated by both approaches were similar at all temperatures. Thermal-death-times from this study will assist the retail food industry to design cooking regimes that ensure safety of ground muscle foods contaminated with E. coli O157:H7.  相似文献   

8.
Gel-forming ability of small scale mud carp (Cirrhiana microlepis) mince and washed mince was investigated with respect to their proteinase and transglutaminase (TGase) activities. Proteinases in sarcoplasmic fluid showed the optimum activity at 65 °C and pH 9, whereas autolytic activity was maximum at 70 °C and pH 10, indicating the presence of heat-stable alkaline proteinases. When mince was washed with three volumes of water twice, TGase and proteinases were mainly removed in the first washing cycle, resulting in a decreased autolytic activity of washed mince. Breaking force of the single washed mince gels was greater than the twice washed mince and the unwashed mince gels (p<0.05). Pre-incubation of mince pastes at 40 °C for 1 h prior to cooking (90 °C/30 min) increased breaking force of all samples, particularly the single washed mince (p<0.05). This coincided with an increase of higher molecular weight polymers observed on SDS-PAGE. Washing did not completely eliminate proteinases as it was evident by an increased trichloroacetic acid (TCA)-soluble oligopeptides of washed gels pre-incubated at 55 °C. Whiteness values of washed mince gels were greater than that of mince gels.  相似文献   

9.
《Meat science》2007,75(4):644-647
In this investigation, the effect of cooking treatments (60 min at 150 °C, 40 min at 200 °C, and 20 min at 250 °C) on aluminium contents of meats (beef, water buffalo, mutton, chicken and turkey) baked in aluminium foil were evaluated. Cooking increased the aluminium concentration of both the white and red meats. The increase was 89–378% in red meats and 76–215% in poultry. The least increase (76–115%) was observed in the samples baked for 60 min at 150 °C, while the highest increase (153–378%) was in samples baked for 20 min at 250 °C. It was determined that the fat content of meat in addition to the cooking process affected the migration of aluminium (r2 = 0.83; P < 0.01). It was also found that raw chicken and turkey breast meat contained higher amounts of aluminium than the raw chicken and turkey leg meat, respectively. Regarding the suggested provisional tolerable daily intake of 1 mg Al/kg body weight per day of the FAO/WHO Expert Committee on Food Additives, there are no evident risks to the health of the consumer from using aluminium foil to cook meats. However, eating meals prepared in aluminium foil may carry a risk to the health by adding to other aluminium sources.  相似文献   

10.
The effects of laccase and transglutaminase (TG) on the firmness and weight loss of cooked chicken meat homogenate gels were investigated at laboratory scale. The salt, trisodium pyrophosphate and meat contents were also used as variables. Laccase decreased firmness and increased weight loss of phosphate-free, low-meat (65%) and low-salt (1%) gels, although it modified myosin and troponin T and reacted with isolated myofibrils. By applying both low-salt (1%) and low-phosphate (0.17%) amounts, gel firmness decreased and weight loss increased (p<0.05) greatly. A high dosage of TG significantly improved (p<0.05) the strength of phosphate-free, low-meat and low-salt homogenate gels compared to the corresponding no-enzyme controls. TG improved gel firmness of the low-meat homogenate to the level of the homogenate containing 75% meat. Weight loss was increased significantly (p<0.05) in all cases when the high-TG dosage was used. Enzymes were not capable of improving either texture or water-holding capacity in the low-salt–low-phosphate system. The firmness and cooking loss of the chicken meat products containing different amounts of meat, salt and TG were investigated at pilot scale. Under the conditions and dosages used, TG was capable of improving (p<0.05) firmness of the products without a significant reduction in water-holding capacity.  相似文献   

11.
Premature browning is a condition wherein ground beef exhibits a well‐done appearance before reaching the USDA recommended internal cooked meat temperature of 71.1 °C; however, the mechanism is unclear. The objectives of this study were: (1) to determine the effects of packaging and temperature on metmyoglobin reducing activity (MRA) of cooked ground beef patties and (2) to assess the effects of temperature and pH on thermal stability of NADH‐dependent reductase, lactate dehydrogenase (LDH), and oxymyoglobin (OxyMb) in‐vitro. Beef patties (lean: fat = 85:15) were packaged in high‐oxygen modified atmosphere (HiOX‐MAP) or vacuum (VP) and cooked to either 65 or 71 °C. Internal meat color and MRA of both raw and cooked patties were determined. Purified NADH‐dependent reductase and LDH were used to determine the effects of pH and temperature on enzyme activity. MRA of cooked patties was temperature and packaging dependent (P < 0.05). Vacuum packaged patties cooked to 71 °C had greater (P < 0.05) MRA than HiOX‐MAP counterparts. Thermal stability of OxyMb, NADH‐dependent reductase, and LDH were different and pH‐dependent. LDH was able to generate NADH at 84 °C; whereas NADH‐dependent reductase was least stable to heat. The results suggest that patties have MRA at cooking temperatures, which can influence cooked meat color.  相似文献   

12.
Six bacterial species were evaluated to determine their inhibitory effects on Clostridium perfringens in vitro (brain heart infusion broth) and in situ (chicken breast meat) under temperature abuse conditions (4 ± 1 °C for 12 h, followed by 7 h at 28 ± 1 °C and then 4 ± 1 °C for 53 h). During abusive storage, rapid growth of C. perfringens from vegetative cell and spore inocula was observed, exhibiting a 2.68–3.37 log CFU/mL (or g) increase in bacterial counts. In the presence of Pediococcus pentosaceus P1 or Lactobacillus fermentum R6, the counts of C. perfringens remained unchanged in the samples containing vegetative cells at the end of storage (P < 0.05); for those containing spores, the germination and outgrowth were also effectively inhibited, decreasing in bacterial counts of > 1.9 log CFU/mL (or g) compared to those of the control (P < 0.05). The pH of chicken meat was slightly declined by 0.09 in the presence of L. fermentum (P > 0.05), and the inhibitory effect against C. perfringens was ascribed to non-acid antimicrobial substances. These results indicate a potential solution for bio-protecting chicken meat from C. perfringens growth.Industrial relevanceClostridium perfringens is a common pathogen that contaminates meat and meat products, but the organism cannot multiply under cold chain conditions at 4 °C. However, it was reported that temperature abuses commonly occurred during the transportation, storage or retail display of the food chill chain. During the abusive storage, C. perfringens could grow rapidly, which may lead to food poisoning. It is a serious problem for food safety.In this study, Lactobacillus fermentum R6 was found to show effective inhibition on both the growth of C. perfringens vegetative cells and the germination and outgrowth of its spores in chicken meat (P < 0.05) under temperature abuse conditions, and also it had a minimal effect on the pH of the meat (P > 0.05). The results reveal a potential technology for bio-protecting chicken meat from C. perfringens growth.  相似文献   

13.
The effect of different rehydration temperatures (30, 40, and 50°C) and cooking times (2.7, 4.7, 6.7, 8.7, and 10.7 min) at 95°C on the pasting properties of three glutinous varieties (Thadokkham-11, Thadokkham-8, and Hom Mali Niaw) from Lao People’s Democratic Republic was investigated using rapid visco analyzer. Non-glutinous varieties (IR64 and Doongara) were also analyzed to compare glutinous (amylose <4.5%) and non-glutinous (amylose >15%) varieties. All rice flours took up water at significantly (p < 0.05) higher rates in the case of increased temperature and soaking time, resulting in a decrease in the onset temperature for pasting. Among the glutinous rices, Thadokkham-8 showed a significant (p < 0.05) decrease in peak viscosity in response to increased rehydration time and temperature. For this variety maximum viscosity (2403.3 mPas) was observed at 1 min of rehydration at 30°C and minimum viscosity (1852.0 mPas) at 15 min of rehydration at 50°C. The viscosity values of Thadokkham-11 and Hom Mali Niaw varieties increased to their highest values (1608.7 and 1477.7 mPa.s, respectively) with an increase in temperature to 40°C for 1 min. In general, the glutinous rices produced weaker gel than non-glutinous rices. Extended holding at cooking temperature (95°C) had a more significant (p < 0.05) effect on the glutinous varieties Thadokkham-8 and Thadokkham-11 than on the non-glutinous varieties (IR64 and Doongara) used in this study.  相似文献   

14.
The state of water in high-pressure-thawed and conventionally water bath-thawed chicken breasts was analyzed using low-field nuclear magnetic resonance. The influence of high-pressure thawing on water holding capacity, including thawing loss, cooking loss and expressible fluid, was evaluated. Thawing loss was significantly reduced (p < 0.05) compared to the conventional thawing method but neither cooking loss nor total expressible fluid changed significantly (p > 0.05). Higher thawing pressures lead to the T21 relaxation time being increased from 39.9 to 55.9 ms, and P21 increased from 89.5 to 94.9 %. Significant negative correlations (p < 0.01) were observed between the thawing loss and T21, T22, P21. These results indicate that high thawing pressures can transform the water from the loosely bound water fraction (T22) to a more tightly bound (T21) water fraction with the increase in water relaxation time.  相似文献   

15.
Glutamic-oxaloacetic transaminase (GOT) activities in chicken and turkey thigh and breast meat samples, thermally processed at 60–84°C in a model heat-treating system, were evaluated for use as indicators of end-point cooking temperatures (EPT). Wings, breasts, thighs and legs from commercially cooked, whole, roasted chickens and commercially processed products containing chicken and turkey meat were analyzed also to determine if residual GOT activities would indicate compliance with recent FDA/FSIS EPT recommendations. Activities of samples processed in the model system decreased logarithmically with increasing temperatures. GOT activities were higher (P < 0·05) in thigh meat than breast meat in both chicken and turkey samples; activities were higher in turkey than chicken. GOT values for chicken thigh and breast meat at 74°C, the FDA/FSIS recommended EPT for use by food handlers and retailers, were 735 and 164 Sigma-Frankel units ml?1 (SFU ml?1), respectively. Values for turkey thigh and breast meat at this temperature were 1080 and 450 SFU ml?1, respectively. The range of activities was 7–13 SFU ml?1 in commercially prepared chicken products and 27–161 SFU ml?1 in turkey products. Analysis of these products showed adequate cooking and compliance with FDA/FSIS recommended EPT for retail sale. These data indicate that residual GOT activity in processed poultry has potential for use as an indicator of EPT.  相似文献   

16.
Four thermotolerant lactic acid bacteria (LAB) were spray dry encapsulated with Acacia gum and inoculated in cooked meat batters. Physicochemical properties (total moisture content, expressible moisture, and cooking stability), pH and acidity, CIE-Lab color, and texture profile analysis were performed at 1 and 8 days of storage at 4 °C. LAB and Enterobacteria counts were determined at 1, 4, and 8 days of storage. Control treatment was inoculated with the same unencapsulated strains as free cells. Total moisture, water activity, and fat release significantly (p?<?0.05) increased in spray drying inoculated samples, with no change in expressible moisture. No significantly (p?>?0.05) difference in pH and acidity were detected between encapsulated LAB and free cells inoculation. Inoculation of spray dry bacteria significantly (p?<?0.05) decreased samples luminosity and redness, with no change in yellowness. In TPA, hardness and springiness had no significantly (p?>?0.05) change due to inoculation type, but cohesiveness decreased in encapsulated samples. Inoculation of spray-dried LAB enhanced initial LAB count with a concomitant Enterobacteria reduction. These results suggest that the spray drying encapsulation is an effective way to protect thermotolerant lactic bacteria. These capsules can be inoculated in cooked emulsified meat products in order to ensure their survival before, during, and after processing. Thermotolerant LAB could be employed as bioprotective cultures to improve microbial safety in cooked meat products since the Enterobacteria counts were diminished during storage, enhancing the nutritional values with no major detrimental effect on textural or physicochemical properties of these kinds of foodstuffs.  相似文献   

17.
Restructured meat is made by binding individual pieces of meat together. To study the effect of mechanical work on the meat binding process, a standard cooking protocol must be established. This paper details the establishment of a standard cooking protocol for the cooking process using untreated beef semitendinosus muscle. The effect of different cooking temperatures and applied loads during cooking were investigated. Meat samples were cut in 20 mm cubes size from beef semitendinosus muscle and two pieces were held together with the muscle fibre parallel to each other by wrapping them with a plastic food wrap. Then the samples were placed inside square steel tubes, that act as a mold for cooking, and different weights (0, 250, 500, 750 and 1000 g) were placed on top of the meat cubes during cooking. The temperatures used for cooking were 60, 70 and 80 °C. There was a significant temperature effect, with increases noted between 60 °C and 70 °C and between 70 °C and 80 °C. At 60 °C neither myosin nor collagen has gelatinized, leading to low binding strengths. At 70 °C the myosin component will have gelatinized. At 80 °C the collagen component will be contributing to the bond. To keep the collagen effect to a minimum the meat should be cooked at 70 °C. The effect of applied cooking load was significant at all cooking temperatures once sufficient load had been applied against no load to ensure good contact at the joint. There was a significant effect of applied load noted at 80 °C with increases up to 750 g and a drop occurring between the 750 and 1000 g loadings. The drop has been attributed to collagen being squeezed out of the joint as a bead of white material was noted around the joint.  相似文献   

18.
This study was conducted in order to tenderise muscle foods (pork, beef and chicken) by using crude enzyme extract from Calotropis procera latex. Chunks of knuckle muscle from pork and beef as well as of breast muscle from chicken were marinated with distiled water (control) and 0.05%, 0.1%, 0.2%, 0.3% and 0.5% (w/w) of crude enzyme extract powder for 60 min at 4 °C. The marinated samples were then subjected to various physical and chemical property determinations. A decrease in moisture content was observed when the crude enzyme extract was added. Firmness and toughness of the muscle samples significantly decreased with the increased addition of crude enzyme extract (p < 0.05). The water holding capacity and cooking yield of the treated samples showed no significant difference throughout the crude enzyme extract addition (p > 0.05). Crude enzyme extract had no effect on the pH of the pork sample, but it slightly increased the pH in the beef and chicken. An increase in protein solubility and TCA-soluble peptides content was observed in all of the treated samples. The electrophoresis pattern of the muscle treated samples also revealed extensive proteolysis occurring in each muscle type. From the results, it is determined that latex from Calotropis procera can be used as an alternative source of proteolytic enzymes for the effective tenderising of meat.  相似文献   

19.
Antioxidant capacity of oil soluble and water dispersible carnosic acid (CA) extracted from dried rosemary leaves using HPLC was evaluated at two different dosages (22.5 ppm vs 130 ppm) in raw and cooked ground buffalo meat patties and chicken patties. Irrespective of total phenolic content, CA extracts reduced (p < 0.05) the thiobarbituric acid reactive substances (TBARS) by 39%–47% and 37%–40% in cooked buffalo meat and chicken patties at lower dosage (22.5 ppm) relative to control samples. However, at higher dosage (130 ppm) the TBARS values were reduced (p < 0.05) by 86%–96% and 78%–87% in cooked buffalo meat and chicken patties compared to controls. The CA extracts were also effective in inhibiting (p < 0.05) peroxide value and free fatty acids in cooked buffalo meat and chicken patties. The CA extracts when used at higher dosage, were also effective in stabilizing raw buffalo meat color.  相似文献   

20.
Selected parameters (cooking loss, instrumental colour and texture and sensory quality) of a brine-injected pork muscle cooked by a novel and rapid ohmic cooking protocol were examined and compared with those obtained in conventionally cooked samples. Ohmic samples were cooked using either a low-temperature long-time (LTLT) protocol (2 min equilibration, 5 min ohmic heating to 70 °C, 8 min holding) or a high-temperature short-time (HTST) procedure (2 min equilibration, 6 min ohmic heating to 95 °C) performed within a hot air cabinet set at 80 °C (LTLT) and 100 °C (HTST). Conventional cooking (steam oven at 80 °C for 120 min) was conducted to a core temperature of 70 °C. The LTLT treatment gave a much lower cooking loss value (4–5% lower, p < 0.05) than the other treatments, though the full magnitude of this difference was not completely reflected in the proximate composition of the cooked products. Ohmically cooked ham showed a significantly (p < 0.05) lighter surface colour with Hunter L values of 65.3 (LTLT) and 63.5 (HTST) relative to the control (61.4). Texture profile analysis (TPA) indicated a significant difference (p < 0.05) in hardness (N) especially between the HTST surface (82.1 N) and the conventional centre (58.8 N). Although the ohmic cooking protocols yielded products with quite acceptable eating qualities, sensory evaluation found the overall quality of the conventionally cooked ham to be significantly (p < 0.05) superior, indicating that further optimisation of the ohmic cooking protocols would be required prior to any commercial adoption.  相似文献   

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