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1.
Sexually mature or late-run chum salmon muscle was packaged in thin-profile retort pouches and in conventional 307 × 200 metal cans. After retort processing to equivalent lethality, samples were evaluated by sensory and instrumental methods. The pouch product was firmer, more fibrous, drier and chewier than the canned. Less late-run flavor and greater overall acceptability were reported for pouch-processed samples. More free liquid was found in pouches than in cans. Histological examination revealed a more compact structure in chum muscle processed in retort pouches, possibly due to air over-pressure applied to flexible pouches during processing.  相似文献   

2.
Thiamin (B-1) ascorbic acid (AA) and vitamin B-6 (B-6) were determined in pouched and canned green beans immediately after processing and after storage at 24–26°C or 38°C. AA and B-6 were also determined in pouched and canned cherries before and after storage at 24–26°C. There was significantly more B-1 and AA in drained pouched green beans, and more AA in drained pouched cherries than in canned ones. B-6 values in the solids of the pouched and canned products were not significantly different. These three vitamins were significantly reduced in drained pouched and canned green beans after storage at 38°C. B-6 was significantly reduced in the stored cherries. Compared to canned, the pouched products were brighter and firmer in texture.  相似文献   

3.
ABSTRACT: Sardine in oil was canned at 3 different Lethality values (F0 5,7, and 9) in retort pouches and aluminum cans in stationary retort. Process time calculations were done mathematically to find out the actual process time. Sardine in oil processed in retort pouches had a lower process time compared with aluminum cans for each F0 value. Instrumental texture analysis was done using a food texture analyzer to study the effect of thermal processing on the texture of thermally processed sardine in oil in aluminum cans and retort pouches. As the F0 value and cook value increased in both the retort pouches and aluminum cans, the textural properties showed a decreasing trend. Hardness of the product canned in both aluminum cans and retort pouches decreased with increase in F0 values.  相似文献   

4.
The physical, chemical and sensory properties of rainbow trout, pollock and shrimp processed at equal lethalities in cans and retortable pouches were compared at certain storage periods. Pouched rainbow trout, pollock and shrimp required respectively 34%, 32% and 37% less thermal processing time than the canned product. The pouched products had lower amounts of ammonia, trimethylamine and total carbonyl compounds than the canned products. The pouched products retained 17%, 9% and 15% more Vitamin B1 than the canned products for rainbow trout, pollock and shrimp, respectively. Pouched products had a firmer texture and lighter color than the canned products. In sensory evaluations, the pouched products were scored higher, in most cases, for color, flavor and overall acceptability.  相似文献   

5.
Traditional metal cans and glass jars have been the mainstay in thermally processed canned foods for more than a century, but are now sharing shelf space with increasingly popular flexible pouches and semi-rigid trays. These flexible packages lack the strength of metal cans and glass jars, and need greater control of external retort pressure during processing. Increasing internal package pressure without counter pressure causes volumetric expansion, putting excessive strain on package seals that may lead to serious container deformation and compromised seal integrity. The primary objective of this study was to measure internal pressure build-up within a rigid air-tight container (module) filled with various model food systems undergoing a retort process in which internal product temperature and pressure, along with external retort temperature and pressure, were measured and recorded at the same time. The pressure build-up in the module was compared with the external retort pressure to determine the pressure differential that would cause package distortion in the case of a flexible package system. The secondary objective was to develop mathematical models to predict these pressure profiles in response to known internal temperature and initial and boundary conditions for the case of the very simplest of model food systems (pure water and aqueous saline and sucrose solutions), followed by food systems of increasing compositional complexity (green beans in water and sweet peas in water). Results showed that error between measured and predicted pressures ranged from 2% to 4% for water, saline, and green beans, and 7% to 13% for sucrose solution and sweet peas. PRACTICAL APPLICATION: Flexible packages have limited strength, and need more accurate and closer control of retort pressure during processing. The package becomes more flexible as it heats and might expand with increasing internal pressure that may cause serious deformation or rupture if not properly controlled and/or counterbalanced with external retort pressure. This article describes methods for determining exactly what the retort pressure profile will need to be to avoid this problem during retorting, and mathematical models to predict these pressures in response to known internal temperature and initial/boundary conditions.  相似文献   

6.
Broccoli, carrots, and green beans (grown in 2 consecutive years) were randomly divided into 3 treatments: fresh-refrigerated (F-R), frozen (FZ) or canned (C) (carrots only). FZ or C vegetables were processed within 24 h and stored for up to 1 yr. F-R vegetables were held at 4 °C for 3 wk (broccoli and green beans) or 6 mo (carrots). Trans b-carotene (Tb-C) and total ascorbic acid (AA) were determined at specified times, before and after microwave cooking. Vitamin content differed between years due to environmental conditions. Blanching resulted in AA loss, but retention remained stable after freezing broccoli and green beans. F-R green beans lost >90% AA after 16 d storage. Linear decreases in AAwere found in most F-R or FZ vegetables. Tb-C decreased slightly during freezer storage. Reductions in Tb-C occurred in canned carrots. Microwave cooking had minimal effects on AA or Tb-C.  相似文献   

7.
ABSTRACT:  The effect of processing time on biochemical, sensory characteristics, and instrumental texture profiles of "Shrimp Kuruma" in retortable pouches and aluminum cans with equal pack weight and lethality was studied. Processing in pouches resulted in a 35% reduction in processing time compared to cans for equal lethality ( F 0 8.0). Thermal processing resulted in a 14% loss of water in canned samples compared to 9% in pouched products. Thermal processing resulted in an increase in the volatile compounds and a decrease in the oxidation products in both canned and pouched samples. Products processed in pouches were rated as lighter in color, more succulent, and more desirable in firmness compared to products in cans. Chewiness and hardness showed a significant difference ( P < 0.05) between the 2 treatments.  相似文献   

8.
ABSTRACT: As an alternative to standard metal cans, 2 large-scale, reusable containers were constructed with volumetric capacities 3.6 to 3.8 times greater and process times 1.36 to 2.05 times longer than a nr 10 can. Effects of increased process time on product quality were measured by conducting objective color and texture evaluations on green beans and pinto beans canned in both containers. Green beans and pinto beans had comparable texture profiles to beans processed conventionally in nr 10 cans. The color of green beans also was comparable; the color of pinto beans was darker, possibly due to contact with the metal container. Color and texture differences were minimal between inner and outer product layers.  相似文献   

9.
Connective heat transfer coefficient at the fluid-particle interface was determined for cut green beans in 303 × 406 cans processed in an agitated retort (FMC Steritort) by measuring the temperature of an aluminum bean and that of the surrounding Newtonian fluid. Four retort reel velocities, two sizes of aluminum beans, and six particle/fluid ratios were employed. Several correlation forms were tested. A correlation was developed in terms of the j-factor, Reynolds number (Re), and shape factor with an R2 of 0.785. the particle's shape was a critical factor in the heat transfer correlations. the fluid-particle heat transfer rate increased with an increase in rotational velocity of the retort.  相似文献   

10.
Hurdle technology combining mild acidification (4.6 < pH < 5.0) and reduced thermal treatment could be a potential preservation technique for the production of high-quality processed canned vegetables once it has been microbiologically validated. Freshly harvested green beans were acidified in pre-prepared brine using one of three acidulants (lactic acid [LA], glucono-delta-lactone [GDL], or fermented dextrose containing organic acids), hermetically sealed in cans, and thermally processed in a pilot-scale water-immersion retort. Eight levels of acidulant concentration (0.01–19.5 g/kg) and five levels of desired lethality (0.01–2.74 min) were applied through uniform shell experimental design (Doehlert network method). The color and texture properties of blanched green beans (control samples) and thermally processed green beans with and without prior acidification were evaluated. Statistical analysis showed that acid concentration had a significant effect on color characteristics, and that lethality had a significant effect on texture indices (p < 0.001). Regression models were developed for the prediction of both color and texture properties of thermally processed acidified green beans with two independent parameters: acidulant concentration and lethality.  相似文献   

11.
Prawn ‘kuruma’ was prepared from Indian white shrimp (Fenneropenaeus indicus), packed in conventional 301 × 206 and 401 × 411 aluminium cans and in thin profile retort pouches having a three-layer configuration of 12.5 μ polyester, 12.5 μ aluminium foil and 85 μ cast polypropylene of size 16 × 20 cm and 17 × 30 cm. The physico-chemical tests conducted on these containers showed their suitability for thermal processing. Prawn to kuruma ratio of 65:35 was maintained in all the containers and heat processed to equal lethality in an over pressure autoclave with the facility to record the time–temperature data, F0 value and cook value. The process time was calculated by using formula method. The processing in 16 × 20 cm and 17 × 30 cm retortable pouch resulted in 35.67% and 56.56% reduction in process time compared with 301 × 206 and 401 × 411 cans, respectively, with equal pack weight. The amino acid content did not vary considerably in both containers. In the canned samples the reduction of sulfhydryl content was 50.54% more when compared with the pouched product. Products packed in pouches were found to be superior to canned products with regard to sensory and textural attributes such as colour, firmness, hardness, chewiness, and overall acceptability.  相似文献   

12.
The economic feasibility of using the retort pouch for processing, packaging and distributing processed fruit and vegetable products during a period of rising energy prices was examined. A retort pouch packaging system was found to be the overall minimum cost packaging system among three packaging systems considered—an existing canning line, a new canning line, and a retort pouch line. Although the costs associated with acquiring and maintaining the durable machinery for retort pouch processing are significantly higher than for a new canning system or an existing canning system, other operating expenditures considered in the packaging systems are considerably lower. Lower freight costs, attributed to the lighter weight and smaller volume of pouches and the comparatively lower purchase price of retort pouches than cans, are the major contributors to the cost effectiveness of the retort pouch packaging system. Energy savings in processing the pouch versus the can are of little significance, but the comparatively lower amount of energy used in transportation and container manufacture has an important role in the cost effectiveness of the retort pouch packaging system.  相似文献   

13.
Spring and fall grown green beans were packed under high and low vacuum conditions in high and low residual Al, Ni, Cu, Si, S, and Mn base steel .25 and .50 electrotin plated J-enamel cans and evaluated during storage at 38°C and room temperature for pitting on and under the s deseams. Cans containing spring grown beans were more severely pitted than those of the fall pack. High residual (0.061%) Cu steel cans were more severely pitted than other treatments. The .25 electrotin plated cans were more severely pitted in high Cu residual cans, as were the low vacuum spring pack cans at 38°C storage.  相似文献   

14.
采用液相色谱-三重四极杆串联质谱(liquid chromatography-triple quadrupole tandem mass spectrometry,LC-MS/MS)法,测定尼龙/聚丙烯(polyamide/cast polypropylene,PA/CPP)蒸煮袋中2 种初级芳香胺(primary aromatic amines,PAAs)物质2,4-二氨基甲苯(2,4-diaminotoluene,2,4-TDA)和4,4’-二氨基二苯甲烷(4,4’-diaminodiphenylmethane,4,4’-MDA)向4%乙酸食品模拟液的迁移量,并研究不同热处理及杀菌方式(巴氏杀菌、蒸、煮、高温灭菌、紫外杀菌)对蒸煮袋中这2 种物质向4%乙酸食品模拟物中迁移的影响。实验结果表明:LC-MS/MS检测2,4-TDA和4,4’-MDA迁移量的检出限均不大于0.02 μg/kg,定量限均不大于0.05 μg/kg,满足欧盟标准中对于PAAs限量的检测要求。在此基础上,研究发现除紫外杀菌对2,4-TDA和4,4’-MDA的迁移无显著影响外,巴氏杀菌、蒸、煮、高温灭菌均会促进PA/CPP蒸煮袋中2,4-TDA和4,4’-MDA向4%乙酸溶液的迁移,迁移量随着迁移温度的升高显著增加(P<0.05)。根据迁移结果可知,在对蒸煮袋包装的食品进行杀菌处理时,紫外和巴氏杀菌是相对安全的处理方式;另外,在对蒸煮袋包装的食品进行加热时,相比煮,蒸是更为安全的一种加热方式。而在121 ℃高温灭菌15 min条件下,2 种PA/CPP样品袋中4,4’-MDA的迁移量分别达到2.733 μg/kg和3.113 μg/kg,均高于欧盟正在修订的对单个PAAs的迁移限量(0.002 mg/kg),具有潜在的食品安全风险。可见,当利用PA/CPP蒸煮袋包装食品时,不同热处理方式对胶黏剂中PAAs的迁移量及食品安全的影响值得重点关注。  相似文献   

15.
We investigated pasteurization and storage of blue crabmeat in steel cans, aluminum cans, plastic cans, nonbarrier pouches, and barrier pouches. Fresh meat was packed in copolymer polyethylene/polypro-pylene cups, Saran® over-wrapped or vacuum skin packaged polystyrene trays, and nonbarrier pouches. Meat pasteurized in plastic and aluminum cans had better sensory and microbiological quality and longer shelf life than meat packed in steel cans. Oxygen-barrier pouches had the lowest quality and shortest shelf life. Nonbarrier pouches had product with quality similar to meat in steel cans, but with an extended shelf life. No packaging materials improved the microbiological shelf life of freshly cooked meat. Vacuum skin packaging resulted in improved sensory qualities of freshly cooked and picked meat.  相似文献   

16.
A microcomputer was interfaced with a batch retort for digital PI control of the retort temperature. Six retort temperature profiles (three isothermal, sinusoidal, step, and ramp) were examined for processing pea puree to nearly the same lethality values in 211 × 400 cans. Thiamine content and steam consumption were measured. Thiamine retentions in non-isothermal processes were greater than in the isothermal processes, but there was no significant difference in the steam consumption.
Lethality and thiamine retention were also simulated using a finite difference model for the same heating profiles, with good agreement with experimental results. the simulation suggests that differences in thiamine retention due to differing heating regimes are significant only for large lethality values and smaller cans. For F0 values smaller than 10 min, the simulation suggests that the sinusoidal heating regime will provide better thiamine retention. Limitations of the model and suggestions for future improvement are also discussed.  相似文献   

17.
Sectioned and formed roast beef, vacuum mixed and heat processed in either retortable pouches or cans, had a lower cook yield than its nonvacuum mixed counterpart. Vacuum mixing had no significant influence on increasing particle-to-particle cohesion (binding strength). Sectioned and formed roast beef cooked in retortable pouches at 121°C (Fo= 6.0) had a higher cook yield and binding strength than product processed at 110°C (Fo= 6.0). Processing the canned product at 121°C (Fo= 6.0) as opposed to 110°C (Fo= 6.0) resulted in no improvement of cook yield or binding strength. Overall, product processed in retortable pouches had a higher binding strength, but a lower cook yield than product processed in cans.  相似文献   

18.
Based on thermal degradation kinetics and heat transfer expressed as the Ball formula method, a simplified approach was used to optimize sterilization processes for thermal softening of white beans (Phaseolus vulgaris, subsp. nanus Metz., variety Manteca de Leon) Constant retort profiles in a still and end-over-end rotary water cascading retort (Barriquand Steriflow) were used. Quality attributes of beans processed at the optimum were evaluated by a trained taste panel and by a tenderometer. Both approaches could distinguish (P<0.01) between attributes of products from optimal rotary and still processes. End-over-end rotation resulted in faster heat penetration and better quality retention of beans. Texture of white beans processed at 4° or 8°C from the optimal temperature could be distinguished (P<0.01) by the sensory panel and by the tenderometer.  相似文献   

19.
The effect of reciprocating agitation thermal processing (RA-TP) on quality of canned beans was evaluated in a lab-scale reciprocating retort. Green beans were selected due to their soft texture and sensitive color. Green beans (2.5 cm length × 0.8 cm diameter) were filled into 307 × 409 cans with carboxylmethylcellulose (0–2%) solutions and processed at different temperatures (110–130 °C) and reciprocation frequency (1–3 Hz) for predetermined heating times to achieve a process lethality (Fo) of 10 min. Products processed at higher temperatures and higher reciprocation frequencies resulted in better retention of chlorophyll and antioxidant activity. However, high reciprocation frequency also resulted in texture losses, with higher breakage of beans, increased turbidity and higher leaching. There was total loss of product quality at the highest agitation speed, especially with low viscosity covering solutions. Results suggest that reciprocating agitation frequency needs to be adequately moderated to get the best quality. For getting best quality, particularly for canned liquid particulate foods with soft particulates and those susceptible to high impact agitation, a gentle reciprocating motion (~ 1 Hz) would be a good compromise.  相似文献   

20.
Fowl meat processed in cans and flexible retortable pouches was evaluated for heat effects on sensory properties. A trained panel evaluated texture and off-flavor of canned boned chicken, uncooked fowl meat retorted in flexible pouches, cooked meat retorted in flexible pouches, and simmered fowl meat (control). Results indicated that the retort pouch process may offer a method for improving the texture of processed fowl meat from spent hens by adequately cooking to tenderize the meat but not overcooking it to the extent that meat chunks are reduced to fibrous, shredded, or stringy components. Off-flavor development was related to pre-cooking before retorting.  相似文献   

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