青岛近海主要海捕水产品中金属元素与石油烃含量分析

目的对青岛近海主要海捕水产品开展质量安全与营养评价研究,掌握捕捞水产品的食用安全现状。方法全面分析青岛近海海域主要捕捞水产品中常量元素、微量元素、稀土元素以及石油烃的含量,并进行食用安全评价分析。结果研究表明青岛近海海域水产品中含有丰富的人体必需元素,是补充人体矿物质营养的良好膳食来源。稀土元素总含量为6.08~232μg/kg,且甲壳类高于鱼类。水产品中鱼类的有害微量元素及石油烃含量均符合我国水产品有毒有害物质限量标准,但甲壳类中梭子蟹和虾蛄的镉(Cd)和少数样品中石油烃含量存在超标情况。结论亟需进一步加强水产品中有害元素的形态分析研究,科学开展风险评估。     

Microbiological and Sensorial Quality Assessment of Ready-to-Cook Seafood Products Packaged under Modified Atmosphere

ABSTRACT:  The effects of modified atmosphere packaging (MAP) (30:40:30 O₂:CO₂:N₂ and 5:95 O₂:CO₂) on the quality of 4 ready-to-cook seafood products were studied. In particular, the investigation was carried out on hake fillets, yellow gurnard fillets, chub mackerel fillets, and entire eviscerated cuttlefish. Quality assessment was based on microbiological and sensorial indices determination. Both packaging gas mixtures contributed to a considerable slowing down of the microbial and sensorial quality loss of the investigated seafood products. Results showed that sensorial quality was the subindex that limited their shelf life. In fact, based primarily on microbiological results, samples under MAP remained acceptable up to the end of storage (that is, 14 d), regardless of fish specie. On the other hand, results from sensory analyses showed that chub mackerel fillets in MAP were acceptable up to the 6th storage d, whilst hake fillets, yellow gurnard fillets, and entire cuttlefish became unacceptable after 10 to 11 d. However, compared to control samples, an increase in the sensorial shelf life of MAP samples (ranging from about 95% to 250%) was always recorded.
Practical Application: Modified atmosphere packaging (MAP) is an inexpensive and uncomplicated method of extending shelf life of packed seafood. It could gain great attention from the fish industrial sector due to the fact that MAP is a practical and economic technique, realizable by small technical expedients. Moreover, there is great attention from the food industry and retailers to react to the growing demand for convenience food, thus promoting an increase in the assortments of ready-to-cook seafood products.     

Modelling and fabrication of optimum structure of novel interdigital sensors for food inspection

Modelling of an interdigital sensor‐based sensing system for the detection of dangerous contaminated marine biotoxin in seafood has been carried out. Three interdigital sensors having new electrode configurations have been analysed using COMSOL Multiphysics. All sensors were designed to have an equal number of electrodes with the same sensing area. Based on the maximum sensitivity, the best electrode configuration has been chosen. Experiments on raw seafood contaminated with domoic acid have been conducted using the new fabricated sensor and very good results were obtained. Copyright © 2011 John Wiley & Sons, Ltd.     

Frozen Storage of Unwashed Cod (Gadus morhua) Frame Mince with and without Kidney Tissue

Removal of kidney material was essential for a higher quality cod frame mince. The removal of kidney tissue before deboning eliminated typical “chemical” and “petroleum” type flavors and resulted in a white, less red, and higher quality unwashed frame mince. Those samples without kidney tissue had good frozen storage stability, (particularly at -40°C) and could be used as an ingredient in apropriate meat products. The length of iced storage of frames or whole cod had little effect on frame mince quality during frozen storage.     

二阶导数恒能量同步荧光法快速测定海产品中的苯并(a)芘

海产品中的多环芳烃主要来自于水体污染,而苯并(a)芘是公认的多环芳烃指标,本文针对海产品中的苯并(a)芘含量的检测,建立了简单快速的海产品中的苯并(a)芘含量的二阶导数恒能量同步荧光检测法。海产品样品经过微波辅助皂化萃取后,正己烷萃取液被旋蒸干,后再溶解于二氯甲烷溶液中,以二阶导数恒能量同步荧光光谱法检测,设定恒能量差为1400 cm-1,扫描范围为300~500 nm,对其中的苯并(a)芘进行快速检测,根据海产品样品的谱图特性,用负峰-基线法读荧光强度值,连续标准加入法进行定量分析,整个光谱扫描所需时间只需1 min。对实际样品检测回收率在80.5%~118.2%之间,检测限为0.10μg/kg,定量限为0.34μg/kg,线性范围为0.34~250μg/kg。对海产品样品的荧光检测结果与HPLC-FL检测结果基本一致,对有证多环芳烃标准物质的检测结果与参考值一致。     

海产鲜味物质及海产品特征滋味的研究进展

素有"海鲜"之称的海产品,以其味道鲜美而备受人们的喜爱。迄今为止,人类所发现的氨基酸、核苷酸、有机酸三类鲜味物质在海产品中都广泛存在,这是海产品鲜味形成的共同物质基础。然而,不同的海产品又呈现出各具特色的特征滋味,这主要归因于各鲜味物质的不同比例以及多种呈味物质的存在。总结了主要海产鲜味物质的研究概况,综述了贝、鱼、虾、蟹等典型海产品特征滋味及其构成的研究进展。并在此基础上预测了今后海产鲜味物质的研究与开发趋势。     

鱼腐生型细菌-问题及解决方法

微生物是引起大多数海洋食物产品腐败的主要原因。然而仅仅有一小部分微生物群体一特殊的腐败有机体（SSOs)，能引起海洋食品腐败。运用微生物生态学、分子技术、分析化学及数学模型，确定并延长产品的保存期。     

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.     

Effect of some habitual cooking processes on the domoic acid concentration in the cockle (Cerastoderma edule) and Manila clam (Ruditapes philippinarum)

The effect of cooking on the concentration and burden of domoic acid in two bivalve molluscs was studied. The Manila clam (Ruditapes philippinarum) and cockle (Cerastoderma edule) were subjected to steaming and boiling, respectively. In both cases, factorial plans were used to evaluate the effects of common cooking methods and the variations likely to take place during the cooking procedure (cooking time and salt concentration in both species, in addition to ethanol percentage in Manila clam). The domoic acid concentration and toxin content were affected by cooking in very different ways in the two species studied. The cockle lost a significant part of its domoic acid content, while the clam did not. Since the weight of the soft tissues in cooked bivalves was lower than in the raw samples in both species, the toxin concentration decreased less than the toxin burden in the cockle, while it increased in the clam, where the toxin burden did not change significantly. Among the cooking variables tested, only cooking time had a noticeable effect on the domoic acid content in the clam and cockle, with the bivalves that were cooked for a longer time having smaller amounts of toxin. It is clear that cooking affects the toxin concentration in bivalves in a way that is species specific. This characteristic must be taken into account when evaluating epidemiological information, establishing allowable toxin levels and in cases where pre-processing treatments such as cooking or similar methods are used in monitoring systems.