天然活性包装膜在冷冻肉贮藏中的应用研究进展

目的 对天然活性包装膜在冷冻肉贮藏中的应用研究进展进行总结,为后续研究提供理论参考。方法 在介绍反复冻融对冷冻肉品质影响的基础上,围绕天然活性包装膜的功能成分、成膜工艺及其在冷冻肉贮藏中的应用研究予以阐述,讨论现有研究的局限性和今后的研究方向。结果 冻融过程中冰晶的反复形成影响冷冻肉体系的细胞结构和理化性质,加剧肉品品质下降;天然活性包装膜可以通过降低干耗、抑制氧化等延长肉品货架期。结论 天然活性包装膜可有效保护冷冻肉品,在肉品保鲜领域具有广阔的应用前景。     

AD5933在肉类阻抗谱测量系统中的应用

为了能够对注水肉的检测提供科学的判断依据,提出了一种基于AD5933的肉类阻抗谱测量方法．该方法利用专用芯片AD5933测量阻抗谱信息,在特定的激励频率下,使用两个针状电极检测受检肉的电信号．每个频率采样3组数据,采用滑动平均算法滤除波动得到最终的阻抗值．研究结果表明,对于1-100kHz的激励频率,可以测量100fΩ-10kΩ之间的复阻抗,测量精度为0．5％,可以用于肉类阻抗谱的测量．     

Conservation en congélation et réfrigération de la viande hachée de boeuf et de porc: évolution de la flore microbienne et des propriétés physico-chimiques en cours de stockage

The minced meat market in Belgium is growing steadily; its share of the market has increased from 10 to 30% in three years. However, the mincing of meat can produce intense microbiol proliferation and thus cause food putrification.Any changes occurring in meat, especially minced meat, are essentially of microbial origin, hence refrigeration is particularly important. With chilling, minimum temperatures must be maintained (0±1°C), since only temperatures below +3°C avoid any health risk linked with the growth of pathogens and production of toxins. Under chilled conditions the storage use of minced meat is four to five days. With freezing, temperatures of about - 18°C are needed to avoid the growth of bacteria, yeasts and mould. At this temperature micro-organisms are progressively rendered inactive, but destruction is never total. The kinetics of reducing micro-organism populations depends on the nature of the micro-organisms, the storage temperature (reduction is more intense at − 12°C that at − 18°C or at − 30°C) and the freezing rate (micro-organisms are better able to resist rapid freezing than slow freezing). One years storage at − 18°C will destroy 90 to 99% of the micro-organisms which were initially present in the product. Nevertheless, the chilled storage (+4°C) of thawed minced meat must not exceed three days.The physico-chemical evolution of cold stored minced meat is explained. In chilled storage, the onset of flavour defects can be related to the measurement of volatile nitrogen. In frozen storage, the crystallisation of the water causes cellular breakdown. The role of packaging is important in avoiding superficial freeze-drying which is accompanied by browning. In addition, fatty matter can deteriorate by oxidation even at freezing temperatures. The degree of alteration of fats can be appreciated by the acidity index and peroxide index (showing that it is undesirable to store minced pork at − 18°C for more than nine months).Use of a partial vacuum or modified atmosphere in combination with impermeable packaging will prolong the storage life of minced meat provided that the initial contamination is as low as possible and the maintenance of the cold chain is strictly respected.

Résumé

Le marché de la viande hachée progresse en Europe, du fait de plusieurs facteurs socio-économiques. Le hachage diminue considérablement la durée de conservation de la viande; sa consommation peut être dangereuse.L'article analyse les points suivants: emballage, réfrigération et congélation (notamment vitesse de congélation), température et durée de conservation, atmosphères modifiées et leur influence sur les propriétés physico-chimiques de la viande et sur le comportement microbien.     

传统风味卤腌熟肉制品软包装保存研究

本试验以五香卤肉和川味香肠为代表，对传统风味的卤腌熟肉制品进行了软包装保存的研究。内容包括复合袋优选、杀菌条件确定及工艺学试验，对热杀菌后引起的产品质地酥软及成品存放中脂肪的析出问题作了探讨，并分析了成品的主要指标，进行了商业无菌检验。     

What Does a Pigeon (Columba livia) Brain Look Like During Homing? Selective Examination of ZENK Expression.

Lesion studies have shown that the avian hippocampus plays a crucial role in homing pigeon (Columba livia) navigation. Using the expression of the immediate early gene protein ZENK in intact pigeons, the authors found regional variation in hippocampal activation as a consequence of homing and, necessarily, the behavior and internal states that accompany it. Specifically, pigeons that homed displayed a significant increase in the number of ZENK-labeled cells in the lateral hippocampal formation compared with pigeons that did not home, whereas no difference was seen in the medial hippocampus. Significant changes in ZENK expression were also found in the medial striatum, which resembles the mammalian ventral striatum. The results identify portions of the hippocampal formation and the medial striatum as sites of plasticity associated with homing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

无边界效应D小波软阈值法去除肉品图像斑点噪声

肉品图像中的斑点噪声与肌内脂肪的颜色特征相似,要准确提取肌内脂肪,就必须先对斑点噪声进行滤除。在小波软阈值法滤除SAR图像中的斑点噪声算法基础上,结合肉品图像的特点进行了改进。首先,使用由耿则勋提出的算法,在小波分解时对左右边界进行处理,重构时外推值为0,对离散小波变换的边界效应进行处理,精确重建图像,消除小波变换的边界效应。选择了D8小波,3级分解后,在不同的阈值下进行了实验。结果表明:阈值的选取影响去噪效果,但在所有参数都相同时,改进算法消除边界效应的同时,在斑点指数和方法噪声两个客观评价指标均优于其他几种边界延拓方式,图像失真最小。     

冻藏肉及其制品中蛋白氧化的研究进展

冻藏是肉及其制品最重要的贮藏方式,可有效抑制微生物生长繁殖及酶促反应,从而延长其货架期.然而,肉及其制品在长期冻藏过程中不可避免地发生品质下降.除冰晶、嗜冷微生物、干耗、脂肪氧化等因素外,蛋白氧化在品质劣化中所发挥的作用受到关注.本文综述肉及其制品中蛋白氧化的发生机制、氧化结果以及检测方法;冻藏过程中影响蛋白氧化的因素...     

NaOH溶液处理对鸡肉品质的影响

为研究NaOH溶液处理对鸡肉品质的影响,选取市售黄羽肉鸡60 只,随机分为对照组和NaOH溶液浸泡组（pH 9组、pH 11组和pH 13组,每组15 只）,并对其进行肉品质和微生物指标检测。结果表明：NaOH溶液浸泡可以显著增加鸡肉的质量和腐败指标（总挥发性盐基氮、组胺、酪胺和亚精胺）含量（P＜0.05）,显著降低剪切力、风味营养物质（蛋白质、肌内脂肪、肌苷酸和氨基酸）含量（P＜0.05）;低pH值NaOH溶液浸泡的鸡肉,其菌落总数和大肠菌群数明显升高,而高pH值NaOH溶液具有一定的杀菌效果。     

北京油鸡遗传育种与品质研究进展

北京油鸡是北京地区特有的肉蛋兼用型鸡种,距今已有300余年历史,以外形独特、肉质鲜嫩、肉香浓郁而著称,是我国优质的地方鸡种,2020年获得国家农产品地理标志登记证书.本文主要从北京油鸡遗传育种、影响北京油鸡屠宰性能及肉质的因素、鸡肉风味物质研究及鸡蛋品质研究等方面进行综述,以期为北京油鸡的规模化养殖、鸡肉品质控制及产品...     

肉类热加工过程中有害物质的形成与控制研究进展

肉类在煎炸、烧烤、蒸煮等加热过程中会产生令人愉悦的香气,但同时也伴随着多种有害物质的产生,如杂环胺、丙烯酰胺、反式脂肪酸、多环芳烃类等,这些物质会对人体健康造成极大危害.因此,探究肉类产品热加工过程中有害物质的成因及控制尤为重要.本文综述上述有害物质在肉类加热过程中的形成机理,总结上述有害物质现有的检测方法及控制手段,...