Development of a Prediction Computer Model for Blue Crab Meat Yield Based on Processing and Biological Variables

The effects of cooking time, cooking method, storage conditions, crab size, crab sex, season, and crab sexual maturity on the total and differential yield of blue crab were determined under commercial processing condition. Crabs cooked for 8 min. yielded more meat than those processed for 12 min. and 10 min. Male crabs yielded more lump and claw meat than female crabs. Clean female crabs also produced more lump and top flake than sponge crabs. A computer program, VTBCP, containing the yield data and prediction equations was developed to predict and calculate the final meat yield (total and differential) based on biological and processing variables.     

Rheological properties and structural changes in steamed and boiled abalone meat

ABSTRACT: Changes in tissue structures, rheological properties, and water content of abalone meat were studied in relation to boiling and steaming time. The adductor muscle of abalone Haliotis discus, which was removed directly from the shell, was boiled or steamed for 1 h, 2 h, and 3 h. When observed under a light microscope and by scanning electron microscopy, structural changes in the myofibrils were greatest in the boiled abalone meat compared with the steamed meat. When heating time was increased from 1 h to 3 h, the instantaneous modulus E ₀ of boiled abalone meat decreased gradually with increased heating time, whereas the E ₀ of steamed abalone meat was reduced when heated for 2 h. When heated for 1 h, the relaxation time of steamed abalone meat was much longer than that of boiled meat. There were no significant changes in the relaxation time of abalone meat among the different boiling times, but the relaxation time of steamed abalone meat was reduced gradually with increasing heating times. The study's results confirmed that the difference in rheological properties between the boiled and steamed meats was due mainly to the denaturation level of myofibrils when heated for 1 h, as well as due to the changes in water and solid content and the manner in which the inner water was exchanged after heating time was increased from 1 h to 3 h.     

Quality and Sensory Characteristics of Volutharpa ampullacea perryi (False Abalone) Meat during the Boiling Cooking

Volutharpa ampullacea perryi (false abalone) meats were water cooked at 75–100°C for 5–60 min, and the changes in weight loss, pH, color, in vitro digestibility, texture, microstructure, and sensory characteristics were investigated. The weight rapidly decreased in the initial cooking and decreased slightly with the extension of both heating temperature and time. Obvious differences in color were found compared between the raw and cooked meats with respect to ΔL*, Δa*, and Δb* values. Digestibility was significantly improved with the thermal treatments. Textual properties, such as hardness, springiness, chewiness, and resilience, improved with the increasing of thermal intensity, but reduced with overcooking, and the variations were further confirmed by the scanning electron microscopy analysis. The samples boiled at 90–95°C for 10–15 min and 100°C for 5–10 min acquired better acceptance in the sensory evaluation. The complex relationship among cooking conditions and physicochemical and histological characteristics of meat as well as the consumer perceptions was illuminated by the principal components regression analysis. These results could provide useful information for quality control in V. a. perryi meat cooking.     

Effects of Culinary Methods on Nutritional Characteristics of the Edible Shellfish Noah’s Ark (Arca noae L., 1758) from Tunisian Coasts

Bivalves are known for their high nutritional value and are considered a healthy food for human consumption. The effect of different cooking methods (steaming, boiling, grilling, and frying) on proximate and fatty acid composition of Arca noae (Bivalvia: Linnaeus 1758) were determined. The comparison of raw and cooked Ark shell showed that the cooking had considerable effects on the nutritional quality of this species. Significant changes in moisture (%), protein (mg/g of flesh), total lipid (mg/g of flesh), and fatty acid composition (mg/g dry weight) were observed after cooking as compared to fresh Ark shell (p < 0.05). However, the analysis of malondialdehyde (MDA) and peroxide value (PV) showed that all cooking treatments led to lipid oxidation. Steaming, boiling, and grilling were found to be a suitable and healthier cooking processes for A. noae, since they conserve the amount of n-3 PUFA better as compared to frying.     

An Improved Process for Retort Cooking Atlantic Blue Crab

Abstract

Non-uniform steam distribution and large temperature differences are frequently found within the retort during pressure steam cooking of blue crabs. A precook treatment involving evacuation of air from the retort prior to introduction of steam was found to decrease this unevenness in temperature distribution. The conventional and modified treatments were compared by (1) determination of temperature profiles within a retort during the conventional cooking process and the modified process; and (2) testing the resulting product from the two processing methods for differences in meat moisture and pH. The modified process improved the temperature distribution and reduced cook time by up to 50%. Meat moisture content increased in crabs processed using the vacuum process while pH testing of the cooked meat showed little difference in meat from the two processes. It was concluded that the improved temperature distribution would shorten cook time and increase throughput, product yield, product safety, and process efficiency.     

Improvement of Cold and Thermally Induced Gelation of Giant Squid (Dosidicus gigas) Surimi

Depending on the season of capture, giant squid (Dosidicus gigas) surimi processed by isoelectric precipitation presents low gel strength. Addition of microbial transglutaminase (MTGase) and application of high isostatic pressure (300 MPa) to improve physicochemical properties were assayed for purposes of making “suwari” gels and heated gels for use in restructured products which have a raw or cooked appearance. The physicochemical properties of both pressurized and unpressurized gels induced by application of 30°C/1 h improved when MTGase was added. In contrast, addition of MTGase was less effective in gels subsequently heated at 90°C/30 min after 30°C/1 h. High pressure treatment for 30 min at 300 MPa and 15°C helped to produce gels with better mechanical and water binding properties, whether treated for 30°C/1 h only or for 30°C/1 h plus 30-min heat treatment at 90°C. High pressure treatment also reduced lightness.     

Pasteurization Conditions and Evaluation of Quality Parameters of Frozen Packaged Crab Meat

ABSTRACT

Ovalipes trimaculatus is a crab recognized as a new resource with fishing value to obtain frozen products. Pasteurization conditions of meat crab at temperatures below 85ºC (60, 72, and 82ºC) were established to achieve better quality attributes in the frozen product. The lethality curves of Staphylococcus aureus and Listeria monocytogenes were measured, and the decimal reduction times (D) and Z values were determined. Heat transfer during the pasteurization process of pouches containing crab meat was simulated using a computational code in finite elements, and the mathematical model was experimentally validated. Thermal histories were coupled to the microbial lethality kinetics of the most heat resistant pathogen microorganism in order to establish pasteurization times necessary for the process system design. The predicted pasteurization conditions were microbiologically validated. The pouches were frozen under industrial conditions and stored at ?22ºC for 1 year. The influence of the type of packaging (vacuum and nonvacuum plastic pouches) on physicochemical and sensory quality parameters of frozen crab meat (color, exudate, lipid oxidation, water holding capacity, and overall acceptability) were analyzed observing better performance under vacuum conditions.     

Nutrient Composition of Raw and Cooked Meat of Male Southern King Crab (Lithodes santolla Molina, 1782)

This study provides information about nutrient composition of adult males of southern king crab (Lithodes santolla). Proximate composition of raw and cooked meat (g/100 g meat) averaged: moisture?=?80.9 and 78.6, protein?=?14.6 and 16.3, fat?=?0.70 and 0.76, and ash?=?2.03 and 2.10, respectively. Arginine, glutamic acid, leucine, and aspartic acid (20.4, 9.4, 8.0, and 7.9 g aa/100 g protein, respectively) were the major amino acids. The predominant fatty acid was 18:1n-9c (21.8 and 22.1%), followed by 20:5n-3 (17.1 and 21.8%), 16:0 (15.8 and 15.3%), and 22:6n-3 (11.0 and 13.5%). Cooked meat contained more cholesterol (51.0 mg/100 g meat) and phospholipids (60.1 mg/100 g meat) than raw meat (37.3 and 13.9 mg/100 g meat, respectively), with phosphatidylcholine representing over 80% of the total phospholipid content. The main tocopherol was α-tocopherol (raw meat?=?1.30 mg/100 g meat, cooked meat?=?1.14 mg/100 g meat). Major mineral contents of raw and cooked meat (mg/100 g meat) were: Na?=?509 and 594, K?=?179 and 203, Ca?=?114 and 197, P?=?126 and 143, Mg?=?34 and 41, Fe?=?1.26 and 1.86, and Zn?=?1.88 and 2.64, respectively. Thus, the nutritional quality of the cooked meat of the southern king crab makes it especially adequate for cholesterol-restricted, balanced low-fat meat diets.     

Physical properties of soft shell clams, Mya arenaria

Soft shell clams, Mya arenaria, are found from Canada to North Carolina on the U.S. Atlantic Coast and from Canada to California on the U.S. West Coast. They are also found in several other parts of the world including Europe. The primary market for these clams on the U.S. East Coast is in New England. Clams are sold whole live or in one of the several cooked forms. Commercial soft clam shucking and processing is primarily by manual methods. However, physical properties data for these clams is lacking and is a constraint on the automation of processing. Several properties of soft shell clams harvested from five different harvest locations in the Chesapeake Bay are detailed in this paper and relationships between the components of the clam are defined mathematically through regression equations. The live weight and the clam length are related to shell weight, siphon weight, meat weight, total solids and free water in the clams. Meat yields under both standard processing methods and for clams steamed and consumed with only the shell removed are detailed. The effect of harvest area on the clam parts is also defined. Soft shell clams shucked manually result in a meat yield of approximately 29% of the live weight. If steamed and eaten the meat yield may be as high as 43% of the live weight, primarily because the siphon is often consumed in steamed clams.     

热塑挤压蒸煮对鱼肉蛋白质营养价值的影响初探

采用胃蛋白酶—胰酶复合处理法对原料鱼肉、蒸煮和罐藏处理的鱼肉产品,以及热塑挤压蒸煮的鱼肉制品进行蛋白质体外消化率的测定,分析比较各种鱼肉制品的蛋白质体外消化率的测试结果;结果表明,挤压蒸煮对鱼肉蛋白质的消化率有一定的影响。     

Rheological properties and structural changes in raw and cooked abalone meat

SUMMARY: In a study of the relationship between structural changes and rheological parameters of raw and cooked abalone meat, abalone Haliotis discus was cooked in boiling water for 3 h, then cut up and separated into cross- and vertical sections. Structural change was observed using a light microscope and scanning electron micrography. The rheological parameters were obtained by stress-relaxation experiments. Microscopic photography revealed that structural change between muscle fibers in both sections of the cooked meat was greater than that in the raw meat. The elastic modulus and rupture strength in both sections of cooked meat showed no difference between the cross- and vertical sections, and were smaller than those for the raw meat. The relaxation time for the cooked meat was also greater than for the raw meat. These results were mainly because of collagen being gelatinized during heating. These changes were also observed by staining collagen and differential scanning calorimetry.     

Quality Evaluation of Grass Carp (Ctenopharyngodon idella) Protein Concentrate Supplemented Noodles

ABSTRACT

The aim of the present study was to evaluate the quality of wheat flour noodles supplemented with 0%, 10%, 20% and 30% grass carp protein concentrate (GCPC). Proximate composition, color analyses, cooking properties (cooking time, cooking loss, swelling index and water absorption index), texture profile analyses (TPA), and sensory evaluations were performed. Significant (p ≤ 0.05) increases in the crude protein (18.94–35.19%), crude fat (0.88–1.06%), and ash (0.89–1.02%) were recorded for GCPC supplemented cooked noodles. Brightness (L*), redness (a*) and yellowness (b*) of GCPC 10–30% fortified cooked noodles was recorded as 77.00–69.97, 1.50–2.81 and 19.08–22.25, respectively. Cooking loss (CL) and optimal cooking time were significantly (p ≤ 0.05) increased with increased level of GCPC from 0%-30%, with readings of 6.13% ?8.90% and 7.53–11.77 min, respectively. Swelling and water absorption indices showed a decreasing trend at 2.33–1.77 and 102.6–78.49%, respectively. A significant (p ≤ 0.05) decreasing trend in hardness (24.50–19.03N) was observed for cooked noodles with increased level of GCPC, while the remaining TPA parameters were significantly different at p> .05. Sensory analyses showed higher preference for control noodles and noodles fortified with 10% GCPC.     

熟制与贮藏对凡纳滨对虾挥发性成分的影响

为研究熟制与贮藏对凡纳滨对虾挥发性成分的影响,采用电子鼻及固相微萃取—气相色谱—质谱联用技术分析虾肉的挥发性成分,并采用相对气味活度值和感官评定法评价虾肉风味的变化。结果显示,熟制与贮藏对虾肉中的挥发性成分影响显著。凡纳滨对虾生虾、熟虾、熟虾冷却、熟虾冷却过夜及二次熟制虾分别被检出50、68、63、49和41种挥发性成分。二次熟制后,虾肉中的挥发性成分有所减少,感官上虾的特征鲜香气也略微减弱;一次熟制对虾肉的风味影响不大。生虾肉中检测出的挥发性成分如壬醛和癸醛等对风味有显著性影响;熟虾肉中检测出壬醛、癸醛和十四醛等;二次熟制的虾肉中检测出对风味影响较大的挥发性成分主要是十八醛、二丁基羟基甲苯等。熟虾经过夜(4°C)放置后,其中检测出的挥发性成分种类和总量均减少,但总量差异不显著。研究表明,熟制可显著增加挥发性风味成分种类和总量,二次熟制与一次熟制相比,凡纳滨对虾的关键风味物质种类和含量显著降低;熟虾冷却后4°C贮藏12 h风味差异不显著。     

Contribution of the polymerization of protein by disulfide bonding to increased gel strength of walleye pollack surimi gel with preheating time

ABSTRACT: To clarify the contribution of polymerization of myosin heavy chain (MHC) by disulfide bonding to increased gel strength of cooked gel via preheating, the pastes of walleye pollack surimi (SS and C grades) were preheated at 25°C and 40°C for a variety of hours prior to heating at 80°C for 20 min. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) patterns of cooked gels were analyzed with and without reducing the samples, which were solubilized in 8 M urea–2% SDS solution. The formation of polymers by disulfide bonding in cooked gels was almost constant in each of the SS and C grade surimi gels despite the period of preheating. Therefore, it was suggested that polymerization by disulfide bonding occurred during cooking at 80°C and not during preheating.     

Changes in taste and textural properties of the foot of the Japanese cockle (Fulvia mutica) by cooking and during storage

Physicochemical changes of Japanese cockle foot parts occurring during cooking and cold storage at 4°C for 10 days were examined. Raw samples decreased in weight by 27% during cooking at 85°C for 15 s. Both raw and cooked samples decreased in weight to the same extent of 22–23% during the 10-day cold storage. The levels of ATP and related compounds, as well as those of free amino acids, were higher in raw than in cooked samples, although the former were found by sensory evaluation to have a stronger fishy odor. Raw samples started to decrease in ATP content after 5 days of cold storage, showing K' values of 18 and 42% after 5 and 7 days, respectively. The L* value in the Hunter scale color evaluation increased during the cold storage of raw samples, revealing a gradual disappearance of its original purple–gray color. Meanwhile, the L* value of cooked samples remained constant during the cold storage. The tensile strength of cooked samples was significantly higher than those of both raw samples before and after the cold storage, indicating increased toughness by cooking.     

Pomegranate (Punica granatum L.) Peel Extracts Inhibit Microbial Growth and Lipid Oxidation in Minced Shrimps Stored at 4°C

Pomegranate peel is inherited with diverse functional properties that improve storage stability and nutritional quality of edible goods. This research was aimed at evaluating antioxidant and antimicrobial properties of pomegranate peel hydro-alcoholic extracts and to determine in situ efficacy of extracts in controlling microbial growth and lipid oxidation of shrimp meat. The results suggest that pomegranate peel ethanolic extracts (PoPetx) have significantly higher (p < 0.05) phenolic contents, 169 mg GAE/100 g accompanied with 90% free radical scavenging activities. Contrary to the normal control, incorporation of PoPetx @ 2.0% (w/w) in minced shrimp meat increased thiobarbituric acid reactive species generation by 10% during 28 days of storage at 4°C. Supplementing PoPetx @ 0.5–2.0% (w/w) to shrimp meat has shown a comparable microbial inhibitory action against total plate counts and Staphylococcus spp. The study concludes that application of pomegranate peel extracts in minced shrimp is a viable strategy to preserve chemical and microbiological quality of shrimp and products of sea origin.     

Algal biomass accrual in relation to nutrient availability and limitation along a longitudinal gradient of a karst riverine system

Textural property of surimi products is a prime factor in determining the acceptability of consumer as well as market value. Gelatin is one of the most popular biopolymers widely used in food industry as gelling agent with the unique textural properties. Therefore, the addition of gelatin along with the use of protein cross-linkers could be a means to modify the texture of surimi gel, which can fit the demand of consumers. Surimi from the threadfin bream (Nemipterus bleekeri) was added with bovine gelatin (BG) and bovine/fish gelatin mix (BFGM; 1:1, 2:1, 1:2, 4:1, and 1:4) at 10% protein substitution in combination with and without microbial transglutaminase (MTGase) at 1.2 units/g surimi. Textural properties, whiteness, expressible moisture content, protein pattern, and microstructure and sensory properties of gels were determined. When MTGase at 1.2 units/g surimi was incorporated, the increases in breaking force and deformation were noticeable in both surimi gels, with and without 10% BG added ( p < 0.05). On the other hand, surimi gels added with BFGM at all bovine/fish gelatin ratios had the higher breaking force and deformation, compared with that added with BG, when MTGase was incorporated. Addition of BG or BFGM lowered the expressible moisture content and whiteness of surimi gel ( p < 0.05). Based on SDS-PAGE, band intensity of myosin heavy chain and actin of surimi gel decreased when surimi gel was added with all gelatins, regardless of MTGase addition. The microstructure study revealed that surimi gel network became finer and denser with the addition of MTGase (1.2 units/g surimi), but the coarser and irregular structure was obtained when gelatin was incorporated. Gelatin, especially bovine/fish gelatin mix, at an appropriate level could be used as the protein additive in surumi gel in conjunction with MTGase in order to improve the textural and nutritive properties of the products.     

Evaluation of Physicochemical and Sensory Properties of Sausages Made with Washed and Unwashed Mince from Nile Tilapia By-products

This study evaluates the effects of inclusion level (60 to 100%) and washing cycles (0 to 2) of minced fish from Nile tilapia fillet by-products on proximate composition, mineral contents, color, hardness, and sensory acceptance of sausages. A complete 2² factorial experimental design was used. Regression models for protein, fat, moisture, minerals, color, and hardness were developed. The optimum combinations for the independent variables are sausages made with 100% non-washed minced fish, which represents a better use of by-products without generating washing residues, leading to less expensive sausage with higher nutritional value.     

Chemical, physical and sensory changes of small abalone meat during cooking

ABSTRACT:   Small abalone meats were heated at 80°C and 98°C for 0–120 min and the differences in chemical, physical and sensory changes of the cooked meats were investigated. The decrease in moisture and weight and the increase in browning and Hunter's b -value were relatively higher for cooking at 98°C than at 80°C. After cooking for 20–120 min, the total amount of adenosine triphosphate and its related compounds on a dry weight basis decreased by 17–27% at 80°C and by 30–39% at 98°C; the total amount of free amino acids on a dry weight basis changed insignificantly at 80°C but decreased by 22–35% after cooking at 98°C. The meats cooked at 80°C were higher in cutting force whereas the levels in the samples cooked at 98°C did not decrease until samples had been cooked for 60 min. The hydroxyproline content showed little change during cooking except for in samples cooked at 98°C for 120 min, in which the content was found to be low. The extended cooking at 80°C improved the acceptability of small abalone meat, whereas only the acceptability score of aroma increased significantly for cooking at 98°C.     

The Effect of Thermal Treatment Method on Fatty Acid Composition in Northern Pike (Esox lucius) Fillets

The aim of the present study was to investigate the effect of thermal treatment methods, such as microwave cooking, steaming, and shallow pan-frying on fatty acids composition in northern pike fillets. All methods of thermal treatment increased fat content in the fillets. Microwave cooking decreased the proportion of saturated fatty acids and increased the proportion of total, n-3, and n-6 polyunsaturated fatty acids as compared with fresh fillets. Steam cooking did not affect the proportion of saturated, monounsaturated, and polyunsaturated fatty acids, whereas pan-frying significantly increased the proportion of monounsaturated and n-6 polyunsaturated fatty acids. All cooked fillets, regardless of the thermal treatment used, had acceptable n–6/n–3 ratio; however, microwave cooking enabled fish products to obtain more beneficial n-6/n-3 ratio than frying. Due to high polyunsaturated fatty acids content and low n-6/n-3 ratio, microwave cooking may be recommended for preparing wild pike fillets in households.