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抗氧化剂对辐照猪肉理化和感官品质的影响 总被引:1,自引:0,他引:1
为减少猪肉辐照灭菌后产生的异味和脂肪氧化,研究了叔丁基对苯二酚、虾青素、维生素E、茶多酚4种抗氧化剂对辐照猪肉理化和感官品质的影响。采用2 g/L抗氧化剂浸泡处理,透氧包装,辐照剂量2.6 kGy,冷藏10 d。分析测定辐照猪肉感官品质、过氧化值、硫代巴比妥酸反应物、挥发性物质、抗氧化剂对羟自由基清除能力,筛选出适合猪肉辐照的高效抗氧化剂。结果表明:叔丁基对苯二酚在储藏期可以很好地减轻辐照异味并抑制脂肪氧化,效果优于虾青素、维生素E、茶多酚。叔丁基对苯二酚和维生素E可以有效地降低脂肪辐照后产生的挥发性物质含量。叔丁基对苯二酚(0.5 g/L)对羟自由基的清除率为52.5%,高于其他抗氧化剂,可抑制猪肉辐照过程中羟自由基参与的反应。 相似文献
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真空包装冷却猪肉低剂量辐照后的理化和感官特性变化 总被引:32,自引:5,他引:32
研究真空包装冷却猪肉经保鲜液处理或未经保鲜液处理,再分别经0 kGy、0.5 kGy、1 kGy和2 kGy低剂量辐照后的理化和感官特性变化,进而确定最佳的辐照处理方式以延长冷却猪肉的货架期。结果表明:经2 kGy辐照的真空包装冷却猪肉在(3±1)℃下贮存21 d时,TVB-N值、TBARS值和汁液流失率分别为20.17 mg/(100 g)、0.347 mg/kg、9.69%;而同样条件下,冷却猪肉首先用保鲜液处理,再经2 kGy辐照,其TVB-N值、TBARS值和汁液流失率分别为17.43 mg/(100 g)、0.237 mg/kg和9.18%。试验说明保鲜液处理可以在一定程度上提高辐照效果。在本试验设定的辐照剂量范围内,随着辐照剂量的增加,冷却猪肉的色泽逐渐变红,当辐照剂量达到2 kGy时,冷却猪肉的色泽达到最佳的鲜红状态,而且在贮存过程中鲜红色泽始终保持稳定,但其TBA值比对照组高(α<0.05),不过大大小于1.0 mg/kg的脂肪氧化酸败临界范围值。冷却猪肉经过保鲜液处理+真空包装+2 kGy剂量辐照+冷藏,可以最大程度地延长冷却猪肉的货架期。 相似文献
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为使电子束辐照在Jeotkal食品产业中得到广泛利用,对鱿鱼Jeotkal发酵食品及配料实施电子束辐照后,分析了鱿鱼Jeotkal发酵食品及配料的微生物和官能特性。结果表明,电子束处理前鱿鱼Jeotkal好氧菌数为2.88logCFU/g,经5kGy处理后,下降为1.76logCFU/g;酵母和霉菌及大肠杆菌初期污染度分别为3.04logCFU/g和4.20logCFU/g,经5kGy辐照后,下降到1.27和1.34logCFU/g,降低2~3log cycle。辣椒粉辐照处理前好氧菌数为4.07logCFU/g,酵母菌和霉菌为3.91logCFU/g,大肠杆菌为4.34logCFU/g。辣椒粉经5kGy辐照后,好氧菌及酵母菌和霉菌显示为ND。蒜糜中初期好氧菌数为4.41logCFU/g,酵母及霉菌为4.48logCFU/g,大肠杆菌为4.32logCFU/g;经5kGy电子束辐照后好氧菌、酵母及霉菌、大肠杆菌都显示为ND。电子束不仅对鱿鱼Jeotkal微生物具有显著的杀菌效果,而且没有引起鱿鱼Jeotkal的pH和官能特性的变化。因此,电子束杀菌技术在低盐或发酵食品储藏工艺中具有很好的应用前景。 相似文献
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本文叙述了γ射线对鲜兔肉品质的影响。试验测定了鲜兔肉辐照后各项品质指标,结果表明:1到60kGy的辐射剂量对鲜兔肉的基本化学组成和氨基酸的含量无明显影响,没有改变兔肉食品的营养结构。辐照后兔肉的挥发性盐基氮随着辐射剂量的增加而增高.与对照组比较有明显差异.但未超过规定的鲜兔肉标准(小于15mg/100g).γ射线对鲜兔肉的蛋白质分解和脂肪的氧化有一定作用,但作用程度很小,并且在适宜的辐照剂量范围内不能引起兔肉的变质。10kGy以上辐射剂量处理的鲜兔肉均出现不同程度的“异味”,并随着辐照剂量的增加而加重,但在低温下,“异味”随着贮藏时间的延长而减弱或消失。密封包装的鲜兔肉用10kGy剂量辐照后,在2±1℃条件下贮藏3个月以上仍属于次鲜兔肉等级。 相似文献
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为探明电子束辐照对醉泥螺的杀菌效果及辐照后醉泥螺感官品质与蛋白质营养价值的变化,为生食醉泥螺的辐照保鲜应用提供理论依据。以生食醉泥螺为研究材料,研究不同剂量电子束辐照对醉泥螺菌落总数、感官评分、蛋白质含量及其氨基酸组成的影响,并分析辐照后醉泥螺在冷藏和常温贮藏条件下的货架期变化。结果表明:1)经1~9 kGy剂量电子束辐照,醉泥螺的色泽和形态几乎没有变化,但7、9 kGy剂量组醉泥螺产生异味;2)辐照剂量越高,杀菌效果越好,当醉泥螺的初始菌落总数为1200 cfu/g时,菌落总数降至初始值10%所需的辐照剂量D10为3.46 kGy;3和5 kGy剂量的辐照对醉泥螺的抑菌效果明显,无论是冷藏还是常温贮藏,360 d内菌落总数均未超过5000 cfu/g;3)辐照对醉泥螺蛋白质含量无明显影响(P?0.05),不改变醉泥螺的限制性氨基酸种类,但经1、3、5 kGy辐照后,氨基酸总量、必需氨基酸总量及各必需氨基酸的氨基酸评分增加;4)结合电子束辐照对醉泥螺菌落总数及感官评分的影响,辐照剂量以3 kGy为宜,醉泥螺保质期冷藏条件下由对照组的5个月延长至12个月,常温条件下由对照组的不到1个月延长到3个月。该结果能为电子束辐照保鲜醉泥螺提供依据。 相似文献
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Modified atmosphere packaging (MAP) is commercially used to increase the shelf life of packaged produce by reducing the produce respiration rate, delaying senescence, and inhibiting the growth of many spoilage organisms, ultimately increasing product shelf life. MAP systems typically optimize O(2) levels to achieve these effects while preventing anaerobic fermentation but fail to optimize CO(2) concentrations. Altering film permselectivity (i.e., beta, which is the ratio of CO(2)/O(2) permeation coefficients) could be utilized to concurrently optimize levels of both CO(2) and O(2) in MAP systems. We investigated the effect of modifying film permselectivity on the equilibrium gas composition of a model MAP produce system packaged in containers incorporating modified poly(ethylene) ionomer films with CO(2)/O(2) permselectivites between 4-5 and 0.8-1.3. To compare empirical to calculated data of the effect of permselectivity on the equilibrium gas composition of the MAP produce system, a mathematical model commonly used to optimize MAP of respiring produce was applied. The calculated gas composition agreed with observed values, using empirical respiration data from fresh cut apples as a test system and permeability data from tested and theoretical films. The results suggest that packaging films with CO(2)/O(2) permselectivities lower than those commercially available (<3) would further optimize O(2) and CO(2) concentration in MAP of respiring produce, particularly highly respiring and minimally processed produce. 相似文献
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果蔬微孔膜气调包装模型与试验验证 总被引:3,自引:3,他引:3
建立微孔膜气调包装的理论模型是保证气调包装质量、进行微孔膜气调包装系统设计的关键。基于孔径与分子平均自由程的关系,应用Fick扩散定理,结合果蔬呼吸速率模型,建立微孔膜果蔬气调包装内外气体交换的数学模型。以香菇为对象,利用密闭系统法确定其呼吸速率;采用硬质罐加PE膜封合包装香菇并在25℃、50%RH下储藏50 h以上,测定不同初始气体组分、微孔孔数与孔径条件下包装内气体浓度变化,对香菇微孔膜气调包装模型进行试验验证。结果表明,模型预测值与试验数据吻合度较高,所建模型能较准确地预测香菇微孔膜气调包装内外气体交换过程。 相似文献
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薄膜气调包装对枇杷果实冷藏期间呼吸和品质性状的影响 总被引:3,自引:4,他引:3
通过对呼吸速率、总可溶性固形物、可滴定酸、pH值、果肉硬度、维生素C、失重率和品质及感官指标的变化进行分析,研究了薄膜气调包装对枇杷(Eriobotrya japonica Lindl.,品种:解放钟)果实冷藏期间呼吸和品质特性的影响,气调包装用的薄膜为低密度聚乙烯薄膜(LDPE,厚度20 μm),以打孔的低密度聚乙烯薄膜包装为对照。结果表明,低密度聚乙烯薄膜包装枇杷果实后,3~4 d后可维持一个相对稳定的适宜枇杷贮藏的O2和CO2的气体浓度,即CO2(4.8±0.67)%,O2(11.5±0.85)%;薄膜气调包装结合低温可明显地降低枇杷果实的呼吸速率;薄膜气调包装可以最大限度地减小冷藏期间的枇杷果实的失重率、果肉硬度、维生素C、总可溶性固形物、可滴定酸和固酸比的变化,维持枇杷的新鲜品质,延长货架期。因此,低密度聚乙烯薄膜(LDPE,厚度20 μm)气调包装可用于枇杷的贮藏保鲜。 相似文献
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Chen G Guttmann RP Xiong YL Webster CD Romaire RP 《Journal of agricultural and food chemistry》2008,56(18):8658-8663
Protease activity during storage is thought to be an important contributor to decreased shelf life of fresh seafood. To examine this, three batches of red swamp crayfish ( Procambarus clarkii) tails, placed on trays, were packed with a polyvinyl chloride film (aerobic packaging or AP), under vacuum (vacuum packaging or VP), or under a modified atmosphere (MAP: 80% CO 2/10% O 2/10% N 2), and proteolytic activity was measured on days 0, 1, 3, 6, and 10 during storage at 2 degrees C. The crude extract from the crayfish digestive system (gut) did not have an apparent role in muscle proteolysis as negligible proteolytic activity was detected. However, the loss of calpastatin (the endogenous calpain inhibitor) was identified in MAP-stored muscle samples on day 10, suggestive of high m-calpain activity. Tail samples stored in AP showed no appreciable proteolysis, but those stored in MAP and VP showed significant decreases in the levels of 53, 66, 71, and 110 kDa polypeptides during storage. The observed proteolytic activity and myofibrillar protein degradation did not correspond to muscle textural properties as the MAP samples had an increased toughness ( P < 0.05) after storage for 10 days. These findings suggest that other physicochemical mechanisms are involved in postmortem alteration in the crayfish muscle structure under the packaging systems investigated. 相似文献
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The aroma compounds in broccoli stored in different modified atmospheres were studied. The packaging materials used were oriented polypropylene (OPP), poly(vinyl chloride) (PVC), and low-density polyethylene (LDPE) containing an ethylene-absorbing sachet. All samples were stored for either 1 week at a constant temperature of 10 degrees C or for 3 days at 4 degrees C, followed by 4 days at 10 degrees C. The atmospheres that developed inside the packaging materials differed significantly. The broccoli samples were analyzed raw and after cooking, with regard to volatile compounds, using gas-phase (headspace) extraction followed by gas chromatography-mass spectrometry (GC-MS) and GC-olfactometry. Dimethyl sulfide (DMS), dimethyl disulfide (DMDS), dimethyl trisulfide (DMTS), hexanal, 3-cis-hexen-1-ol, nonanal, ethanol, and a group of thiocyanates were selected for a detailed study because these compounds cause off-odor and can be used as indicators of stress. Significant differences were found in the aroma profiles of the broccoli samples relative to the packaging materials used for storage. Storage in OPP (14% O(2), 10.5% CO(2)) resulted in most of the off-odors, while storage in LDPE (6% O(2), 7% CO(2)) and PVC (17.9% O(2), 4% CO(2)) was found to maintain the concentration of DMS, DMDS, and DMTS during storage. Heat treatment of the broccoli increased the content of aroma compounds as well as the number of compounds containing sulfur. 相似文献
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该文主要考察25℃下气调和真空包装对腌制海鳗货架期的影响.4个样品分别是M1:空气包装(对照),M2:真空包装,M3:CO2/N2,40%/60%,M4:100%CO2,以挥发性盐基氮,三甲胺,pH值,硫代巴比妥酸值,菌落总数和感官为指标.结果表明,气调包装的货架期为20 d,真空包装为19 d,对照为16 d.对照组细菌增加很快,而M4增加最慢.挥发性盐基氮和三甲胺都随着储存时间延长而增加,在气调包装下的感官质量明显好于对照组.气调和真空包装,特别是100%CO2包装是保藏腌制海鳗的最有效方法. 相似文献
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Rangkadilok N Tomkins B Nicolas ME Premier RR Bennett RN Eagling DR Taylor PW 《Journal of agricultural and food chemistry》2002,50(25):7386-7391
The effects of post-harvest and packaging treatments on glucoraphanin (4-methylsulfinylbutyl glucosinolate), the glucosinolate precursor of anticancer isothiocyanate sulforaphane [4-methylsulfinylbutyl isothiocyanate], were examined in broccoli (Brassica oleracea var. italica) during storage times. The results showed that at 20 degrees C, 55% loss of glucoraphanin concentration occurred in broccoli stored in open boxes during the first 3 days of the treatment and 56% loss was found in broccoli stored in plastic bags by day 7. Under both air and controlled atmosphere (CA) storage, glucoraphanin concentration appeared to fluctuate slightly during 25 days of storage and the concentrations under CA was significantly higher than those stored under air treatment. In modified atmosphere packaging (MAP) treatments, glucoraphanin concentration in air control packaging decreased significantly whereas there were no significant changes in glucoraphanin concentration in MAP with no holes at 4 degrees C and two microholes at 20 degrees C for up to 10 days. Decreases in glucoraphanin concentration occurred when the broccoli heads deteriorated. In the present study, the best method for preserving glucoraphanin concentration in broccoli heads after harvest was storage of broccoli in MAP and refrigeration at 4 degrees C. This condition maintained the glucoraphanin concentration for at least 10 days and also maintained the visual quality of the broccoli heads. 相似文献