Fresh Crab Meat Research Articles

Pilot Scale Assessment of High-Pressure Processing (HPP) to Enhance Microbiological Quality and Shelf Life of Fresh Ready-to-Eat (RTE) Blue Crab Meat.

Blue crab (Callinectes sapidus) is a highly valuable wild fishery species of crab native to the waters of the western Atlantic Ocean and the Gulf of Mexico. The annual commercial production of live blue crabs is approximately 50,000 metric tons with a dockside value of USD 200 million. Presently the US blue crab processing industry sells crab meat in three basic forms: fresh crab meat, pasteurized crab meat, and frozen crab meat. By far "Fresh" is the most desirable form of crab meat. However, fresh crab meat has a limited shelf life. This study evaluated the effects of high-pressure processing (HPP) on enhancing the microbiological quality and shelf life of blue crab meat. Live blue crabs were pressure-cooked in a retort (≥115 °C for 4-6 min). The crab meat was handpicked, packed in plastic containers with seals, subjected to HPP treatment, and stored at 4 °C. Container integrity and water leakage issues were examined by observation in addition to weight comparison before and after HPP treatment; the shelf life of crab meat with and without HPP treatments was examined via microbiological tests and sensory evaluations. Results show that polypropylene containers sealed with 10K OTR (oxygen transmission rate) film could withstand high pressure without water leakage issues; HPP treatment at 600 MPa for 3 min could extend the shelf life of fresh, cooked, and handpicked crab meat from 6 days to 18 days based on the strictest APC (aerobic plate account) limit (APC ≤ 100,000 CFU/g). The sensory quality of the HPP-treated crab meat was well accepted throughout the 3-week storage period. The results support the use of HPP as an effective non-thermal processing technology to enhance the microbiological quality and extend the shelf life of fresh RTE blue crab meat.

Changes in digestive enzymes and nutritional ontogeny reserves in newly hatched Pacific pygmy octopus, Paroctopus digueti

In this study, changes in digestive physiology and nutritional reserve content during the early stages of the Pacific pygmy octopus, Paroctopus digueti, were examined. Body growth, biochemical composition (soluble protein and glycogen concentrations) in the digestive gland and arm muscle, hepatosomatic index, as well as lipases and proteases (acid and alkaline) activities were determined every two days up until 14 days after hatching. Newly hatched octopuses were obtained in the laboratory, from the eggs of a female that spawned in the wild and were kept in individual chambers and fed fresh crab meat. A significant decrease in soluble protein was observed in both, the digestive gland (8 days after hatching) and the arm muscle (2–4 days after hatching). Thereafter, soluble protein gradually increases in digestive gland whereas, in the arm muscle, afterward a significant increase at 6 days after hatching, a decreasing pattern until 14 days after hatching was noticed, possibly due to the start of exogenous feeding. In arm muscle, 2 days after hatching the glycogen showed a peak with subsequent marked fluctuations up to 14 days after hatching, indicative of the complete use of internal nutritional reserves and dependence on exogenous feeding at this time. Higher lipase activity was observed 2 days after hatching, with a significant decrease occurring between 6 and 14 days after hatching. Acid protease activity increased between 6 and 14 days after hatching, while alkaline protease activity remained stable during the developmental period, with a peak occurring 8 days after hatching. These results contribute to the further understanding of this critical period of transition from endogenous to exogenous feeding that takes place between 6 and 8 days after hatching and may be useful in developing effective feeding schemes employing natural or formulated foods for this species.

A Predictive Model for the Growth of Listeria monocytogenes in Commercial Blue Crab (Callinectes sapidus)

During the processing and handling of commercial blue crab (Callinectes sapidus), Listeria monocytogenes can potentially contaminate cooked meat and grow to hazardous levels. To manage this risk, predictive models are useful tools for designing and implementing preventive controls; however, no model specific for blue crab meat has been published or evaluated. In this study, a cocktail of L. monocytogenes strains was added to pasteurized blue crab meat, which was incubated at storage temperatures from 0 to 35°C. At selected time intervals, L. monocytogenes was enumerated by direct plating onto modified Oxford agar. A primary model was fitted to kinetic data to estimate the lag-phase duration (LPD) and growth rate (GR). Listeria monocytogenes replicated from 0 to 35°C, with GR ranging from 0.004 to 0.518 log CFU/h. Overall, the LPD decreased with increasing temperature, displaying a maximum value of 187 h at 0°C; however, this trend was not consistent. The LPD was not detected at 10°C, and it occurred inconsistently from trial to trial. A secondary GR model (R2 = 0.9892) for pasteurized crab meat was compared with the L. monocytogenes GR in fresh crab meat, demonstrating bias and accuracy factors of 0.98 and 1.36, respectively. The model estimates varied from other published data and models, especially at temperatures ≥5°C, supporting the need for a specific predictive tool for temperature deviations.

Survey for Listeria monocytogenes in and on Ready-to-Eat Foods from Retail Establishments in the United States (2010 through 2013): Assessing Potential Changes of Pathogen Prevalence and Levels in a Decade

A multiyear interagency Listeria monocytogenes Market Basket Survey was undertaken for selected refrigerated ready-to-eat foods purchased at retail in four FoodNet sites in the United States. Food samples from 16 food categories in six broad groups (seafood, produce, dairy, meat, eggs, and combination foods) were collected weekly at large national chain supermarkets and independent grocery stores in California, Maryland, Connecticut, and Georgia for 100 weeks between December 2010 and March 2013. Of the 27,389 total samples, 116 samples tested positive by the BAX PCR system for L. monocytogenes , and the pathogen was isolated and confirmed for 102 samples. Among the 16 food categories, the proportion of positive samples (i.e., without considering clustering effects) based on recovery of a viable isolate of L. monocytogenes ranged from 0.00% (95% confidence interval: 0.00, 0.18) for the category of soft-ripened and semisoft cheese to 1.07% (0.63, 1.68) for raw cut vegetables. Among the 571 samples that tested positive for Listeria-like organisms, the proportion of positive samples ranged from 0.79% (0.45, 1.28) for soft-ripened and semisoft cheese to 4.76% (2.80, 7.51) for fresh crab meat or sushi. Across all 16 categories, L. monocytogenes contamination was significantly associated with the four states (P < 0.05) but not with the packaging location (prepackaged by the manufacturer versus made and/or packaged in the store), the type of store (national chain versus independent), or the season. Among the 102 samples positive for L. monocytogenes , levels ranged from <0.036 most probable number per g to 6.1 log CFU/g. For delicatessen (deli) meats, smoked seafood, seafood salads, soft-ripened and semisoft cheeses, and deli-type salads without meat, the percentage of positive samples was significantly lower (P < 0.001) in this survey than that reported a decade ago based on comparable surveys in the United States. Use of mixed logistic regression models to address clustering effects with regard to the stores revealed that L. monocytogenes prevalence ranged from 0.11% (0.03, 0.34) for sprouts (prepackaged) to 1.01% (0.58, 1.74) for raw cut vegetables (prepackaged).

Pressure-Induced Germination and Inactivation of Bacillus cereus Spores and Their Survival in Fresh Blue Crab Meat (Callinectes sapidus) During Storage

ABSTRACT Pressure-induced germination and inactivation of three strains of B. cereus spores by high hydrostatic pressures between 100 and 550 MPa at 40°C for 15 min was studied. In sterile distilled water, spore germination remained stable with pressures up to 300 MPa, and increased at pressures between 300 and 500 MPa, with maximum germination and inactivation obtained at 550 MPa. Of the 3 strains, spores from the crabmeat isolate were found to be the most resistant to germination and inactivation by pressure. In fresh crabmeat the B. cereus spores were more resistant to inactivation, but germination was improved compared to spores suspended in distilled water. Fresh crabmeat inoculated with B. cereus spores, treated with high pressure (550 MPa, 40°C, 15 min) and then stored at 4 and 12°C for 31 days showed that B. cereus was not a competitive organism in the presence of crabmeat microflora. Some pressure-sensitive microflora were inactivated in the treated crabmeat, but B. cereus survived through the end of the 4°C storage period.

Quality Characteristics of Fresh Blue Crab Meat Held at 0 and 4°C in Tamper-Evident Containers

There has been a regulatory movement toward the required use of tamper-evident containers for fresh blue crab meat. North Carolina passed tamper-evident regulations in 1993. Blue crab processors had little information on possible changes in head-space gases, microbial growth, chemical decomposition, sensory quality, or shelf life caused by the new containers. Chemical, microbiological, physical, and sensory changes in fresh crab meat were monitored during 18 days of storage in ice and 13 days of storage refrigerated at 4°C. “Special” blue crab meat, chosen for the study, is the least expensive commercial form of white crab meat. The crab meat was packaged in four retail containers: copolymer polyethylene cups with polyethylene snap-on lids, copolymer polyethylene cups with snap-on polyethylene lids fastened to the cup with heat-shrink low-density polypropylene seals, copolymer polyethylene cans with aluminum easy-open ends, and copolymer polypropylene cups with a tamper-evident pull-tab on the lid. Control samples packaged in industry standard copolymer polyethylene cups maintained higher oxygen levels than meat stored in tamper-evident containers. No consistent differences in quality or shelf life were detected among the containers. Market shelf life was limited to 6 days for meat held at 4°C and 15 days for meat held at 0°C. Sensory quality deteriorated 6 days earlier for crab meat held at 4°C than meat held at 0°C. Collateral work showed that toxin production by Clostridium botulinum neither occurred following 18 days of storage at 4°C nor after 15 days of storage at 10°C. Definite spoilage occurred before any toxin production. The study suggests that blue crab processors can safely use the new tamper-evident packaging, which has little or no effect on product quality or shelf life. Processors may choose appropriate packaging options using price, packaging quality, market appearance, and ease of production as the deciding criteria.

The effects of cryoprotectants on the sensory properties of frozen blue crab (Callinectes sapidus) meat

AbstractThe sensory properties of cryogenically frozen crab meat, treated with polydextrose, a blend of sucrose/sorbitol/phosphate or water was compared with pasteurised crab meat using both trained and consumer panels. Samples were vacuum sealed, cryogenically frozen and stored at −29°C for 32 weeks. A trained panel evaluated changes in appearance, aroma, flavour, and texture at periods of 0, 4, 8, 16, 20, 24, 28 and 32 weeks while a consumer panel evaluated sensory changes after 0, 16 and 32 weeks of storage. An untreated cryogenically frozen reference sample was stored at −65°C. Polydextrose and sucrose/sorbitol/phosphate treatments were closest in sensory attributes to fresh crab meat in that they had fewer adverse changes in quality than the water, reference or pasteurised treatments. Panellists detected more sour, rancid, and ammonia notes and less fresh crab flavor in the pasteurised sample. All of the cryogenically frozen samples were closer to fresh crab meat, in quality attribute terms than pasteurised crab mat. Consumer panel evaluations were in agreement with trained panel assessments showing that cryoprotectants were effective in delaying the deterioration of sensory attributes during frozen storage.

Effect of Freezing, Additives, and Packaging Techniques on the Quality of Processed Blue Crab Meat

Experiments were conducted to study the effect of freezing technique on quality of Blue crab meat. Freshly processed crabmeat was used as a control. The treatments were evaluated by a trained sensory panel and analyses for trimethyl amine (TMA), total volatile base (TVB), and pH. The first experiment involved comparisons of crabmeat pre-treated with malic acid vs. phosphate, can vs. vacuum packaging in plastic pouches and storage at −18 and −30 C for 8 months. The results indicated that freezing and storing of crabmeat in a conventional air-circulating freezer (−18 C) significantly reduced the quality (aroma, flavor, texture, appearance) when compared to fresh crabmeat. Even when stored at −30 C, the quality was substantially lower than that of fresh crabmeat after 1½ months of storage. The two packaging methods and application of malic acid or phosphates did not prevent quality deterioration. A second experiment included a similar design except that the effect of freezing crabmeat with dichlorodifluoromethane (“Freon” Food Freezant) was compared with conventional freezing. The same packaging method was used but the additives were omitted. Freezing with “Freon” for 1½ month caused no significant difference in meat quality when compared with fresh crabmeat (stored 0 days) but quality of the frozen crabmeat decreased significantly after 1½ months. Storage at −18 C was unsatisfactory for both freezing methods. TMA, TVB, and pH analyses were not of major value in assessing the quality of the fresh or frozen crabmeat.

Incidence of Clostridium botulinum in Crabmeat from the Blue Crab

The incidence of Clostridium botulinum in fresh crabmeat of blue crab was six out of 986 samples; in pasteurized crabmeat one sample out of 1,000 contained the organism.

Incidence of Clostridium botulinum in Crabmeat from the Blue Crab

The incidence of Clostridium botulinum in fresh crabmeat of blue crab was six out of 986 samples; in pasteurized crabmeat one sample out of 1,000 contained the organism.

EFFECT OF THE NITROFURAN–FURYLFURAMIDE–ON CRAB MEAT QUALITY

The effect of furylfuramide [2-(2-furyl)-3-(5-nitro-2 furyl) acrylamide] on extending the shelf life of fresh crab meat was investigated. Results show that furylfuramide inhibited growth of the natural flora of crab meat (in vitro study). Very little growth occurred ill a medium containing 1 ppm of furylfuramide. Even less growth occurred in one containing 5 ppm. Aerobic plate counts of treated crab meat stored for 12 days indicated that treatment in a 5-ppm solution was as effective as treatment in a 20-ppm solution. Exposure of crab meat for 5 min to a 5 ppm solution gave optimum inhibition, all factors considered.The pH and ammonia content of samples correlated well with results of organoleptic tests. Organoleptic analysis show that furylfuramide extended the shelf life of crab meat by 2 to 4 days. Treatment of fresh picked crab meat in a 5–ppm solution of furylfuramide does not affect its appearance.

Irradiation preservation of Pacific Coast fish and shellfish—IV. Storage life of Dungeness crab meat at 33°F (0.5°C) and 42°F (5.5°C)

Laboratory-scale studies were made to determine for fresh Dungeness crab meat the optimum radiation conditions directed toward defining commercial process parameters. Fresh crab meat was obtained from 4 different processing plants, packed in either C-enameled cans or in polyester-polyethylene pouches, irradiated at doses ranging from 0.1 to 0.5 Mrad with a Co 60 source, and tested for storage characteristics at 33°F (0.5°C) and 42°F (5.5°C). Irradiation at 0.1- and 0.2-Mrad range produced a freshlike product with an increased storage life of 2–5 times greater than that of the unirradiated product; these low doses are therefore recommended for initial commercial application. Vacuum packing and nonvacuum packing in cans were equally effective in extending the shelf life of radiation-pasteurized crab meat. Storage life at 33°F (0.5°C) is almost double that at 42°F (5.5°C).

Ammonia as an Index of Decomposition in Crabmeat

Abstract A method, based upon the color reaction between NH3, thymol, and bromine, uses ammonia as an index of decomposition in fresh or frozen crabmeat. The color is extracted into re-butyl alcohol and net absorbance is determined by subtracting absorbance at 475 mμ. from that at 682 mμ. Sensitivity is about 1 ppm NH3. The method is very rapid and requires no special apparatus. Samples of crabmeat decomposed under controlled conditions were examined and graded organoleptically. Ammonia content was determined and found to increase uniformly and rapidly with spoilage. Good reproducibility and low results were obtained on fresh crabmeat. Ammonia can be detected by the method before spoilage can be detected organoleptically.

BACTERIOLOGICAL STUDIES OF FRESH CRABMEAT

Journal of Food ScienceVolume 6, Issue 2 p. 157-167 BACTERIOLOGICAL STUDIES OF FRESH CRABMEAT LEONARD C. TOBIN, LEONARD C. TOBIN Louisiana State University, University, LouisianaSearch for more papers by this authorC. S. McCLESKEY, C. S. McCLESKEY Louisiana State University, University, LouisianaSearch for more papers by this author LEONARD C. TOBIN, LEONARD C. TOBIN Louisiana State University, University, LouisianaSearch for more papers by this authorC. S. McCLESKEY, C. S. McCLESKEY Louisiana State University, University, LouisianaSearch for more papers by this author First published: March 1941 https://doi.org/10.1111/j.1365-2621.1941.tb16279.xCitations: 9AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume6, Issue2March 1941Pages 157-167 RelatedInformation