共查询到20条相似文献,搜索用时 46 毫秒
1.
草鱼冷藏过程中新鲜度的综合评价 总被引:1,自引:0,他引:1
为研究养殖草鱼冷藏过程中的鲜度变化,以菌落总数、挥发性盐基氮(total volatile basic nitrogen,TVB-N)含量、pH值以及表征新鲜度的K、Ki、Fr、G、H、P值为指标,并结合电子鼻分析其新鲜度。结果表明,草鱼4 ℃冷藏过程中,随贮藏时间的延长,菌落总数和TVB-N含量呈增长趋势,与贮藏时间分别呈极显著相关(r=0.977)和显著相关(r=0.897);K、Ki、Fr、G值和P值均与贮藏时间呈极显著相关,相关系数r分别为0.955、0.953、-0.953、0.958和0.957;H值和pH值与其他实验指标相关性均不显著。菌落总数、TVB-N含量、K值及相关值(H值除外)和电子鼻结果能有效区分不同贮藏时间的草鱼。电子鼻检测结果和K值及相关值(H值除外)较菌落总数和TVB-N含量对新鲜度评价更为灵敏,pH值和H值不适宜作为冷藏草鱼的新鲜度评价指标。4 ℃冷藏条件下的草鱼,货架期为8 d,12 d后不可加工和食用。 相似文献
2.
3.
4.
5.
以草鱼(冰藏0、1、3、7 d)作为研究对象,探讨冰藏期间鱼肉新鲜度如pH值、挥发性盐基氮(totalvolatile base nitrogen,TVB-N)值、可溶性肌浆蛋白(soluble sarcoplasmic proteins,SSP)值、可溶性肌纤维蛋白(soluble myofibrillar proteins,SMP)值和色泽(L*、a*、b*)的变化规律,以及在巴氏杀菌条件下(80、90 ℃,10 min)蒸煮损失率、收缩面积比及色泽的变化。结果表明:草鱼冰藏过程中,TVB-N值由11.8 mg/100 g增加至16.87 mg/100 g,略低于淡水鱼上限值20 mg/100 g;pH值在前3 d由6.72降低到6.52,之后上升至6.56;SSP值无明显变化,SMP值在前3 d逐渐增加,之后轻微下降;鱼肉色泽变化值(ΔE)逐渐升高,表明鱼肉在冰藏7 d期间新鲜度逐渐下降。在热加工过程中,鱼肉逐渐变成白色,蒸煮损失率、收缩面积比和ΔE值随鱼肉冰藏时间的延长而缓慢下降。 相似文献
6.
7.
为研究冷藏草鱼肉在贮藏过程中酸度(pH值)与汁液流失率、色差值、挥发性盐基氮(total volatile basic nitrogen,TVB-N)值、硫代巴比妥酸(thiobarbituric acid,TBA)值、菌落总数等指标之间的关系及变化规律。以市售草鱼作为试验材料,切成鱼段杀菌包装,每24 h测定以上指标。试验结果表明,草鱼肉在4℃下存放10 d,每隔24 h测定的pH值和挥发性盐基氮值呈直线正相关(P<0.01),且更为客观准确,回归方程为Y=33.833X-220.44(P<0.01),决定系数R2=0.978 2。通过pH计测定的pH值,可以求出挥发性盐基氮值,此模型可更为快速地测定草鱼新鲜度。 相似文献
8.
为解析冷藏草鱼肉品质变化机制,本实验分别采用气相色谱-飞行时间质谱法和透射扫描电子显微镜分析了草鱼肉4 ℃冷藏0、24、72 h后小分子代谢物组成和超微结构变化。结果发现,随着冷藏时间延长,草鱼鱼肉肌纤维间隙变大、排列开始散乱,部分肌节发生断裂。代谢组学共鉴定到211 种代谢物,其中42 种代谢物的含量变化倍数超过1.5 倍(P<0.05)。乳酸、磷酸累积是鱼肉pH值下降的主要原因。本研究发现三羧酸循环途径代谢物中只有琥珀酸含量显著降低(P<0.05),转化成4-羟基丁酸甲酯和γ-氨基丁酸,这3 种化合物水平可能是冷藏草鱼肉新鲜度潜在评价指标。多不饱和脂肪酸(如亚麻酸、花生四烯酸)含量显著下降(P<0.05),但壬二酸含量显著增加(P<0.05)。冷藏过程中,缬氨酸、L-半胱氨酸含量显著增加(P<0.05)。草鱼肉冷藏过程中,脂肪氧化先于蛋白质降解。草鱼肉中含有的植物次级代谢物(胡椒碱、柚皮素、茉莉酸甲酯、马钱子苷、α-蛔蒿素、枞酸、3,4-二羟基扁桃酸)可通过抑制黄嘌呤氧化酶影响鱼肉核苷酸代谢及鱼肉滋味。 相似文献
9.
真空包装鲈鱼片在冷藏与微冻贮藏过程中的新鲜度评价 总被引:3,自引:0,他引:3
以淡水鲈鱼为对象,采用真空包装方法,研究鲈鱼片在冷藏(4 ℃)和微冻(-2 ℃)条件下的新鲜度变化情况。以菌落总数、pH值、挥发性盐基氮(total volatile basic nitrogen,TVB-N)值、K值为指标,结合电子鼻对冷藏和微冻鲈鱼片的气味进行检测,并对所获得信息进行主成分分析,综合评价其新鲜度。结果表明,随着贮藏时间的延长,不同温度贮藏的鲈鱼片其菌落总数和K值均呈上升趋势,温度越低,上升越慢;贮藏初期pH值呈先下降后升高的趋势;电子鼻分析结果与菌落总数、K值结果保持一致,能有效区分不同新鲜度的鲈鱼片。综合各指标变化,与冷藏相比,真空包装鲈鱼片微冻贮藏能保持较好新鲜度,货架期更长。 相似文献
10.
研究竹叶抗氧化物对三文鱼贮藏过程中品质变化的影响。将三文鱼片浸渍于0.2%竹叶抗氧化物溶液中,0℃条件下贮藏。以感官评定、菌落总数、挥发性盐基氮(TVB-N)、p H值、K值及TBA为评价指标,研究竹叶抗氧化物对冷藏三文鱼的保鲜效果。结果显示:在贮藏期间,三文鱼片的感官评分值呈下降趋势;菌落总数、挥发性盐基氮(TVB-N)及K值均随时间的延长呈上升趋势;TBA虽规律性不强,但大体呈上升趋势;p H值呈先降低后上升的趋势。浸泡0.2%竹叶抗氧化物的三文鱼片各项评价指标均低于对照组,感官评分值优于空白对照组,可使三文鱼片的冷藏货架期延长2 d~4 d。 相似文献
11.
12.
对脆肉鲩鱼片在4种包装处理(镀冰衣+真空包装、不镀冰衣+真空包装、镀冰衣+非真空包装、不镀冰衣+非真空包装)下冻藏(-18℃)8 w过程中,理化、质构和感官品质的变化进行了研究。不同包装处理对干耗和TBA值的变化有显著影响。不同包装条件下粘着性无显著差异,而硬度、咀嚼性和回复性因受包装处理方式不同而存在显著差异。随着冻藏时间的延长。包装的条件对脆肉鲩鱼片各感官指标影响较大。与镀冰衣相比较,真空包装能更有效地防止脆肉鲩鱼片冻藏过程中理化、质构及感官品质的劣化,若在鱼片冻藏过程中采用镀冰衣与真空包装相结合的方法则能更有效地防止品质的劣化。 相似文献
13.
14.
15.
本试验研究真空包装对羊肉冰温贮藏期间品质的影响,从而确定更优的羊肉贮藏方法。以羊肉为原料,比较冰点(-2℃)下真空包装与空气包装的羊肉在贮藏过程中pH、色差、质构特性、感官、挥发性盐基氮(TVB-N)、菌落总数等指标的变化。结果表明:在冰温条件下,与普通包装相比,真空包装能使羊肉保持良好的色泽(P>0.05),延缓羊肉pH、TVB-N和菌落总数的增长,并且使货架期延长3 d。真空包装贮藏至第24 d时菌落总数为5.94 lg cfu/g,TVB-N为13.67 mg/100 g,仍在安全范围。在贮藏末期,真空包装色泽显著优于空气包装(P<0.05)。冰温条件下,空气包装和真空包装相比并没有对羊肉的质构特性(硬度、粘附性、弹性)产生显著性影响(P>0.05)。研究结果表明,在贮藏期内真空包装的羊肉贮藏品质更优。 相似文献
16.
D. O'BEIRNE ALISON BALLANTYNE 《International Journal of Food Science & Technology》1987,22(5):515-523
A modified-atmosphere packaging system for chilled fresh potato strips, which rapidly produced oxygen levels < 3%, was identified. This system enclosed the strips within 25 μ low density polyethylene film heat sealed to a fibre tray lined with Surlyn-PVdC-Surlyn, and the package flushed with an initial atmosphere of 5% O2 , 10% CO2 . An equilibrium-modified atmosphere of 3–4% CO2 , 1–2% O2 was established after 3 days' storage at 5°C. This modified-atmosphere package, used in combination with dipping of potato strips in a 10% ascorbic acid solution, inhibited enzymatic discoloration for 1 week at 5°C. Vacuum packaging within a Surlyn/PVdC-coated polyester film, with or without dipping in ascorbic acid solution, inhibited discoloration of chilled potato strips stored at 5°C for at least 2 weeks. 相似文献
17.
18.
Dawei Yu Panying Li Yanshun Xu Qixing Jiang Wenshui Xia 《International Journal of Food Properties》2017,20(2):390-401
This study investigated the effect of chitosan coating (1 and 2%) on the quality of grass carp fillets stored at 4°C for 20 days. During storage, the physicochemical properties (pH, thiobarbituric acid value, total volatile basic nitrogen value, trimethylamine nitrogen value, K-value, water loss, and instrumental texture), microbiology (total viable count and psychrotrophic count), and sensory properties were evaluated. The results showed that chitosan coating could effectively inhibit bacterial growth, improve physicochemical and sensory qualities, and it reduced the deterioration of the quality of grass carp fillets. Compared with fillets without chitosan coating, the shelf life of fillets with 1 and 2% chitosan coating was extended by ~3 and 6–7 days, respectively. 相似文献
19.
20.
SHERYL M. AVERY REA R. ROGERS R. GRAHAM BELL 《International Journal of Food Science & Technology》1995,30(6):725-735
Beef steaks of normal pH (5.3–5.5) were inoculated with Listeria monocytogenes , individually packaged in saturated carbon dioxide atmosphere packaging (SCAP) for <3 h or 5 or 8 weeks or in vacuum packaging (VP) for <3 h, and stored at −1.5°C. After each storage period, 27 individually packaged steaks were removed from their storage packs, overwrapped and placed on retail display under conditions simulating gross temperature abuse (12.25°C). Other steaks were removed from their storage packs and rinsed to remove L. monocytogenes cells, which were re-inoculated onto freshly cut beef steaks to simulate cross-contamination. These crosscontaminated steaks were overwrapped and also subjected to abusive display. Meat pH did not change significantly during storage or retail display. During the retail display of steaks previously stored in SCAP, the lag phase of aerobic bacteria and lactic acid bacteria was longer after prolonged storage compared to short (<3 h) exposure to carbon dioxide. For the same samples, L. monocytogenes failed to grow during retail display or grew only slightly after a prolonged lag phase (>75 h), even after only brief exposure time (<3 h) to carbon dioxide. In contrast, with cross-contaminated steaks, when the inocula had been exposed to SCAP or VP for a short time (<3 h) the L. monocytogenes lag phase was shorter (<20 h). Inocula from steaks stored in SCAP for 5 or 8 weeks did not grow on the cross-contaminated steaks. It is concluded that exposure of both the beef substrate and the L. monocytogenes inoculum to carbon dioxide during prolonged chilled storage does not increase the risk of growth of L. monocytogenes when that meat is subsequently placed on retail display, nor is there a large risk of growth of L. monocytogenes where cross-contamination from SCAP stored raw beef to fresh raw beef occurs prior to retail display. 相似文献