Characterization of Minced Meat Extracted from Blue Crab Picking Plant By-Products

Blue crab meat was mechanically extracted from picking-room byproducts to produce the following minced meat yields: 3.18%, white; 10.71%, mixed; 6.39%, claw, and 2.62%, leg. Each meat had distinct visual, textural, and flavor attributes. Aerobic plate counts of unpasteurized minced meat ranged from 10⁵ to 10⁷ CFU/g. Extraction within 1.5 hours of picking or icing of by-products prior to mechanical extraction stabilized microbial levels. Meat pasteurized at 80.6°C darkened or blued significantly less than meat processed at 83.3°C. Addition of citric acid-phosphate buffer to meat pasteurized at 80.6°C further reduced darkening of meats.     

Volatile Components in Blue Crab (Callinectes sapidus) Meat and Processing By-Product

Volatile components in fresh-picked blue crabmeat and processing byproduct were compared by simultaneous steam distillation-solvent extraction/gas chromatography/mass spectrometry (SDE/GC/MS). Compounds were identified in crabmeat (771 and by-product (80) of which 58 were common to both. Some compounds 154) were identified for the first time in crab. Trimethylamine, four alkanes (C15–C17, C19), and indole were highest (> 50 ng/g)) in crabmeat, while trimethylamine, carbon disulfide, dimethyltrisulfide, two alkanes (C15 and C17), geranylacetone, and 1–dodecanol were highest in by-product. Of compounds from both samples, 23 were higher in by-product and 7 were higher in the meat. Crab processing by-product may be a good source for volatile flavor recovery.     

不同气调包装对熟制蟹肉蟹黄贮藏品质的影响

熟制蟹肉蟹黄由于蛋白质和脂肪含量较高,暴露在空气中极易被氧化,腐败变质,使货架期大大缩短,严重限制了产品生产和销售规模。本文以熟制蟹肉蟹黄为研究对象,探讨不同气调包装方式（空气,60% CO₂+40% N₂和40% CO₂+60% N₂）在4℃贮藏条件下对其品质的影响,分析风味物质变化规律和货架期,最后确定产品最优气调包装方式。研究结果显示,与空气组比较,气调包装组的菌落总数、pH、挥发性盐基氮及丙二醛含量明显降低,且40% CO₂+60% N₂组效果最佳;40% CO₂+60% N₂组样品挥发性风味物质随时间变化损失较少,呈味核苷酸腺苷酸（AMP）含量显著减少,肌苷酸（IMP）、肌苷（HxR）及次黄嘌呤（Hx）显著增加（P<0.05）,感官评价得分最高,货架期可达到28 d左右,比空气包装组延长了8 d。因此在4℃贮藏条件下采用40% CO₂+60% N₂气调包装能有效提高熟制蟹肉蟹黄的风味品质和货架期限,是一种较好的冷藏保鲜方式。

     

Aroma Volatiles in Cooked Alligator Meat

Volatile components from cooked (convection oven at 176.7°C for 30 min) alligator meat were isolated by vacuum simultaneous distillation and solvent extraction (V-SDE) and dynamic headspace sampling (DHS) and analyzed by gas chromatography combined with mass spectrometry, Fourier transform infrared spectroscopy, or olfactometry. We identified 56 compounds in V-SDE extracts and 13 in DHS extracts. Volatile profiles were similar for all alligator meat samples regardless of alligator size (length). However, concentration of volatiles increased as alligator size increased. Most volatile compounds were lipid-derived aldehydes, which made up 73.9–79.4% of total volatiles in V-SDE extracts and 82.4–89.2% in DHS extracts. Hexanal, the most abundant compound, and (Z)-4-heptenal were considered responsible for the green, grassy and fishy, rancid off-odor of cooked alligator meat samples.     

Transfer of the Meat Aroma Precursors (Dimethyl Sulfide, Dimethyl Disulfide and Dimethyl Trisulfide) from Feed to Cooked Pork

Eight pigs were given standard concentrate feed to a live weight of 70 kg. Subsequently half the pigs were controls and were fed the concentrate feed, while the other half of the pigs were fed an experimental diet consisting of the concentrate feed (89 percent of calories) and Brussels sprouts (11 percent of calories) the last 4 weeks before slaughter. Analyses of volatiles in chops and gastro-intestinal contents were performed using solid-phase micro extraction and subsequent characterization by gas chromatography-mass spectrometry. The ratio between the amount of dimethyl sulfide found in the stomach contents from pigs fed Brussels sprouts and the stomach contents from pigs fed the control diet was 9.0, and correspondingly the ratio was 475.5 for dimethyl disulfide and 8.3 for dimethyl trisulfide. The ratio between the amount of dimethyl sulfide found in meat from pigs fed Brussels sprouts and meat from pigs fed the control diet was 14.9, and correspondingly the ratio was 4.8 for dimethyl disulfide and 1.9 for dimethyl trisulfide. Moreover, several other compounds seem to be influenced by feed composition. Finally, the increase in concentration of sulfur compounds in meat in relation to pork aroma is discussed.     

Minced Meat Crabcake from Blue Crab Processing Byproducts—Development and Sensory Evaluation

Quantitative and qualitative characteristics of minced meat, mechanically separated from blue crab processing by-product, were determined. Sensory evaluation was performed on crabcakes with various combinations of claw mince/meat (CMM), surimi, and functional soy protein concentrate (SPC). Separation produced 50–58% food-grade mince from picking table by-products and 49% from undersized claws. Claw mince had lower microbial concentrations than the composite picking table by-products. Crabby and beany flavors were influenced (p<0.05) by the CMM ratio but not by SPC. No significant differences were observed for textural characteristics using various levels of CMM. Sensory firmness and cohesiveness scores marginally correlated (p<0.1) with Instron compressive force measurements. Food-grade undersized crab claw mince can be used in value-added products.     

酶法水解蟹腿肉的研究

对比研究复合蛋白酶、复合风味蛋白酶、木瓜蛋白酶、胃蛋白酶、胰蛋白酶及中性蛋白酶水解蟹肉的效果 ,选择木瓜蛋白酶为水解蟹肉蛋白的最适酶种。单因素研究表明 ,在木瓜蛋白酶水解蟹肉反应的最初 1h内 ,水解率达到 47% ,此后水解率增加速率逐渐减慢 ,4h后不再变化 ;E/S为 40 0 0U/g时 ,酶解反应的水解率较高 ,且能满足生产要求 ;酶解反应的水解率随固液比的增加有较大幅度地增加 ,固液比为 1∶2 5较合适 ;酶解反应的最适温度和pH值分别为 60℃、5 0。     

蟹肉双酶复合水解工艺的研究

以蟹肉为原料,利用多种蛋白酶对蟹肉中的蛋白质进行水解,挑选中性蛋白酶1398以及Flavourzyme两种蛋白酶进行复合酶解,得出酶解的最佳工艺参数为:中性蛋白酶1398的酶底比为300U/g、Flavourzyme的酶底比为1200U/g、Flavourzyme的作用时间为14.5h、总时间为16h、底物浓度为2%。水解后,总氮回收率达到81.82%。     

中华绒螯蟹蟹肉和蟹黄中挥发性风味物质组成

采用同时蒸馏萃取技术(SDE)方法提取中华绒螯蟹中的挥发性风味成分,利用气相色谱-质谱联用技术(GS-MS)对提取的中华绒螯蟹蟹肉和蟹黄中挥发性风味成分进行分离鉴定。结果表明：在中华绒螯蟹中共检测到97种挥发性化合物。其中,蟹肉和蟹黄中含有的挥发性化合物的数量分别为60种和67种,仅有30种挥发性化合物被检测到同时存在于蟹黄和蟹肉中;中华绒螯蟹蟹黄和蟹肉中的挥发性成分在组成上的差别主要体现为在醇类、芳香类、烷烃类和含硫类化合物的组成上,这可能是导致中华绒螯蟹蟹黄和蟹肉香气差异的主要原因;除了组成上的差异,蟹黄中检测到的挥发性化合物的含量普遍高于蟹肉中检测到的化合物的含量。     

低值花蟹肉松加工工艺

主要研究了低值花蟹肉松的加工工艺,探讨了肉松加工过程中煮制时间等四个主要加工工艺参数及辅料蛋白粉的添加工艺,同时研究了VE对肉松保藏过程中过氧化值的影响,结果表明:煮制时间2 h,烘干时间6 h,烘干温度60 OC,炒松时间1 h;产品可采用添加适量大豆蛋白与鸡蛋蛋白粉的方法降低生产成本,改善产品质量,具体添加比例为1.5%,两种蛋白粉配比为2︰1;同时可在产品中添加0.2%的VE以提高产品的保藏性能。     

陕西特色臊子肉特征香气物质解析

采用固相微萃取(solid-phase microextraction,SPME)结合气相色谱-质谱联用(gas chromatography-mass spectrometry,GC-MS)技术分析陕西地区市售11种臊子肉挥发性成分,通过对重要香气成分进行定性及定量分析,并结合香气活度值(odor activity ...     

Thermal Gelation of Previously Cooked Minced Meat from Jonah Crab (Cancer borealis)

ABSTRACT:  Crab processing typically involves picking meat from whole cooked product. Remaining meat can be recovered as mince and potentially processed into value-added products. This study focused on gelation of commercially processed crab mince. Objectives of the research were to determine the effects of cryoprotectants, freezing, and various heat treatments on gel formation of washed mince from previously cooked crab. Previously frozen minced meat from thermally processed Jonah crab was washed to remove soluble components. Four different treatments were applied to the washed mince: (1) freezing with cryoprotectants, (2) freezing with no cryoprotectants, (3) no freezing with cryoprotectants, and (4) no freezing with no cryoprotectants. Unwashed mince was used as a control treatment. Sodium chloride (2.5%) was mixed into the mince prior to stuffing into sausage casings and heating at 35 °C/30 min, 90 °C/30 min, or 35 °C/30 min followed by 90 °C/30 min. Gels were tested for proximate composition, color, water-holding capacity, and gel strength. All mince samples formed gels except for the unwashed control. Gels with no cryoprotectants had 10% to 20% greater water holding capacity, lower L* values, and greater gel strength than those with cryoprotectants. Freezing of washed mince resulted in lower water-holding capacity of gels and higher a* values. A 2-stage heating treatment resulted in gels with the greatest gel strength, whereas gels cooked at 35 °C had the greatest distance to fracture. Results indicate that protein gels can be formed using previously cooked crab meat, which may be useful in the development of value-added products.     

不同模型体系产肉香味化合物的对比

为了探讨不同pH值对美拉德反应产肉香味化合物的影响,文中将硫胺素、半胱氨酸、核糖、木糖组成5个不同的模型体系,用0.2mol/L,pH值分别为4.5、5.0、5.5、6.0、6.5、7.0的磷酸盐缓冲液溶解,125℃反应3h。采用动态顶空制样,结合气相色谱-质谱联用(GC-MS)技术对反应产物中的2-甲基-3-呋喃硫醇、双(2-甲基-3-呋喃基)二硫化物、2-糠硫醇、3-巯基-2-戊酮、壬醛、辛醛进行定量分析。结果发现:硫胺素和半胱氨酸组成的体系在pH=5.5时产生的2-甲基-3-呋喃硫醇最多;含有戊糖的4个反应体系则产生了较多的2-糠硫醇;半胱氨酸和戊糖组成的体系只有在pH≤5.5时才可产生2-甲基-3-呋喃硫醇。5个体系均未检测到双(2-甲基-3-呋喃基)二硫化物和3-巯基-2-戊酮,检测到少量的辛醛和壬醛。     

Storage Changes of Fresh and Pasteurized Blue Crab Meat in Different Types of Packaging

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.     

模拟蟹肉复合保鲜技术研究

评价生物保鲜剂（水溶性壳聚糖0.4%+食用级植酸0.04%）结合气调包装（75%CO2+25%N2）和冰温〔（-2±0.5）℃〕贮藏的复合保鲜技术对模拟蟹肉的保鲜效果。通过测定样品的菌落总数、理化指标和感官指标及其与贮藏时间的相关性,分析V₁（真空包装）、V₂（真空包装+保鲜剂）、M1（气调包装）和M₂（气调包装+保鲜剂）等处理方式对冰温贮藏条件下模拟蟹肉品质的影响。结果表明,模拟蟹肉冰点为（-3.4±0.5）℃,添加保鲜剂后冰点基本不变。冰温贮藏模拟蟹肉的合适温度为（-2±0.5）℃。模拟蟹肉贮藏至56d时,各组样品的菌落总数都小于1 logCFU/g,保持良好的感官品质。贮藏至70d时,V₁组样品菌落总数为3.32logCFU/g,其它3组样品的菌落总数均小于1logCFU/g。贮藏70d后V₂、M₁和M₂组样品细菌总数均呈明显的上升趋势。经综合评定,冰温贮藏条件下V₁样品的货架期为84d左右,M₁和M₂样品的货架期为98d左右,V₂样品的货架期最长,可达到100d以上。研究结果显示复合保鲜技术可明显抑制腐败菌的繁殖,延缓感官品质的下降,在模拟蟹肉产业化中显示了良好的实际应用前景。菌落总数、硬度、胶着性的变化与贮藏时间呈显著正相关,感官评分、凝聚性、回复性与贮藏时间呈显著负相关。将这些指标作为反映模拟蟹肉品质变化的指标。而pH、TVB-N、白度在贮藏期变化不大,不适合作为反映模拟蟹肉品质变化的指标。     

风味蟹肉软罐头护色工艺优化

以小规格蟹的蟹肉为原料,研究了风味蟹肉软罐头制备过程中的护色工艺优化.以L*值、b*值及相对褐变程度作为评价指标,通过单因素试验和正交试验设计研究4种护色剂(柠檬酸、D-异抗坏血酸钠、抗坏血酸和植酸)的浓度、护色时间对风味蟹肉高温灭菌后色泽的影响.最终得到风味蟹肉的最佳护色工艺为:0.4％柠檬酸和0.2％D-异抗坏血酸...     

波动温度模拟蟹肉副溶血性弧菌生长模型

研究模拟蟹肉在4℃~28℃范围内副溶血性弧菌的生长动力学曲线,采用Belehradek方程描述温度对副溶血性弧菌的生长动力学影响。通过在设计的波动温度下模拟蟹肉中副溶血性弧菌的生长动态模型而得到预测值,并与在此波动温度下副溶血性弧菌的实测值进行比较,本文同时采用了偏差因子和准确因子来验证模型对波动温度的预测适用性。     

Influence of Gender and Spawning on Meat Quality of Australian Red Claw Crayfish (Cherax quadricarinatus) Stored at 2 °C

ABSTRACT:  Shell-on tails of male (M), nonspawning female (F), and spawning female (SF) Australian red claw crayfish ( Cherax quadricarinatus ) ( n = 270) were aerobically stored at 2 °C up to 10 d to monitor meat quality changes under a retail condition. Percentage protein of SF muscle was higher ( P < 0.05) and moisture and ash content lower ( P < 0.05) than those of M and F muscles. The pH of muscle changed during storage, with SF generally having a lower value than M or F ( P < 0.05). Lipid oxidation increased during the 1st 5 d and no significant difference existed between the 3 muscle groups. Cooking yield of SF (91.72%) at 10 d was significantly lower than that of M (96.25%) or F (97.81%), and its muscle shear force was also higher ( P < 0.05) than M at 0, 3, 5, and 7 d and than F at 5 and 7 d. Sensory panel results (cooked meat tenderness, juiciness) were significantly correlated with instrumental results (shear force, cooking yield), with SF showing a lower meat tenderness, juiciness, and overall acceptability than M and F samples.     

熟肉制品卫生的监督结果分析

通过对仓山区1996～1998年熟肉制品监督抽查的结果分析,讨论分析了影响熟肉制品卫生合格率的几个主要因素,提出提高熟肉制品卫生合格率的关键措施在于改善生产销售环境和加强监督力度。而加强基层监督力量和加强从业人员岗位卫生培训应是今后进一步提高熟肉制品卫生监督有效性的关键。