Lipid damage in farmed rainbow trout (Oncorhynchus mykiss) after slaughtering and chilled storage

The flow ice system including ozone (OFI condition) was tested for slaughtering and storage (up to 16 days) of farmed rainbow trout (Oncorhynchus mykiss). Lipid damage analyses were carried out and compared to sensory acceptance and instrumental colour changes. Comparison to individuals processed with the flow ice system in the absence of ozone (FI condition) was undertaken. Rainbow trout slaughtered and chilled under FI and OFI conditions showed a low lipid damage development, according to lipid oxidation and hydrolysis events and lipid composition (polyunsaturated fatty acids, phospholipids and endogenous antioxidants) changes. Additionally, both icing conditions led to largely good quality and shelf life times and to the absence of changes in colour properties. It is concluded that flow ice as such, or including the presence of ozone, can be considered as ideal strategy to be employed as slaughtering and storage system during the commercialisation of the actual farmed species. The ozone presence has shown some profitable effects as leading to an extended shelf life time by quality retention of several sensory parameters; in contrast, some negligible negative effects could be observed on the secondary and tertiary lipid oxidation development. However, the oxidation values reached by individuals kept under OFI conditions cannot be considered as particularly high.     

An intervention method for occupational safety in farming -- evaluation of the effect and process

In order to increase safety in Swedish farming an intervention methodology to influence attitudes and behaviour was tested. Eighty eight farmers and farm workers in nine groups gathered on seven occasions during 1 year. The basic concept was to create socially supportive networks and encourage discussions and reflection, focusing on risk manageability. Six of the groups made structured incident/accident analyses. Three of the latter groups also received information on risks and accident consequences. Effects were evaluated in a pre-post questionnaire using six-graded scales. A significant increase in safety activity and significant reduction in stress and risk acceptance was observed in the total sample. Risk perception and perceived risk manageability did not change. Analysing incidents/accidents, but not receiving information, showed a more positive outcome. Qualitative data indicated good feasibility and that the long duration of the intervention was perceived as necessary. The socially supportive network was reported as beneficial for the change process.     

Exploring the potential of fur farming wastes and byproducts as substrates to anaerobic digestion process

Mink farming is a well-established economic activity with a significant environmental footprint. In this work mink farming derived organic waste was assessed, for the first time, as substrate to anaerobic digestion plants. The substrates assessed were; (a)fresh mink manures, (b)weathered mink manures, (c)waste feed and (d)mink derived meat and bone meal. Substrates with in inoculum to substrate ratio of 2 offered specific methane productions ranging between 368 and 591 mLCH₄/gVS_added corresponding to 67.4 and 91.1% of their theoretical methane potential. In the second phase of the experiments three organic loading rates and three inoculum to substrate ratios were assessed. Substrate/inoculum ratios, in batch mode, lower than 1 seem to affect negatively the process, due to slow hydrolysis and acetogenesis of the macromolecules. In addition, initial organic loading rates of up to 50 gVS/L can be applied in batch systems when manure is utilized as substrate. In contrast to this, when mink derived byproducts are used the same loading rate will result into an irreversible process inhibition due to the accumulation of intermediate products.     

Cash farming in building and construction: a stochastic analysis

Cash flow management is a significant issue in the management of a building or construction firm. This paper steps back from the well researched area of poor cash management and its relationship with failure, to focus on the funds which are generated through operations, and the positive benefits which can follow in a well managed organization. A stochastic model is developed which illustrates how an average of 16% of turnover can be available for reinvestment. This is sufficient to allow investment in non-liquid assets, provided that this is managed carefully and precautions are taken against a severe reduction in turnover. This level of funds is sufficient to encourage firms to enter the industry with the motivation of generating funds, rather than a desire to build. This has implications for large clients and for government when dealing with the industry.     

沿海非传统农区县域聚落空间演化研究 —— 以浙江省宁海县为例

县域是城乡融合发展的重要载体。随 着中国城镇化进程的加快,沿海非传统农区县 域聚落空间也发生了剧烈变化。本研究以浙江 宁海县为例,综合运用中心地理论、位序规模法 则、分形维数等理论方法,分析1990—2020年 浙江宁海县域聚落空间演化特征。结果发现：宁 海县域聚落空间演化规律与典型农作区差异明 显,趋向于城市发展规律,但因为县域人口和经 济发展的局限性,与城市特征仍有差距;聚落规 模沿中心轴线高核聚集,三门湾区点状高核突 出,镇乡职能明确,形成了较为稳定的多中心网 络等级结构;同时宁海县域聚落通过四种演化 方式向外扩张。探究非传统农区县域聚落规模 分布的演变规律,构建聚落等级体系,对县域聚 落体系的优化和城乡融合发展具有重要意义。     

Fatty acid profiles in meat from Caiman yacare (Caiman crocodilus yacare) raised in the wild or in captivity

Chemical composition and fatty acid profiles were determined in Caiman yacare meat originating from the neck and tail cuts of animals raised in the wild (n = 6) or in captivity (n = 6), slaughtered at a live weight of approximately 6 kg. All experimental methods were approved by the appropriate environmental protection agencies. Most chemical components were affected by the origin-cut interaction, with the tail cut of wild animals having the highest amount of intramuscular fat (19.2% of DM) and the lowest of moisture (71.8%) and protein (77.0% of DM). Yacare meat had low amounts of SFA (35.1%), which were similar (P > 0.05) in the cuts and origins studied. The total amount of PUFA was higher (P < 0.05) in wild (31.0%) than in captive animals (23.6%), and n − 3 fatty acids had means of about 5% and 2% for the same groups, respectively (P < 0.05). In general, the FA profile of intramuscular fat in yacare meat had a desirable PUFA/SFA ratio above 0.4.     

城市农耕景观规划理论研究

近年来由于自然灾害和人为因素的影响,使得食品安全危机不断地出现在我们身边,人们对于健康绿色生活的愿望越来越迫切。文章通过规划手段,对现实中发生的一些关于人们的生活、饮食等相关问题从城市园林景观角度进行规划分析,通过利用城市农耕景观和城市园林景观相互结合的理论方法,提出了城市农耕景观规划的理论框架,进而给人们创造一个能够参与到环境营造和食品生产等一系列的活动的机会。文章提出了城市农耕景观的垂直空间规划、地域空间规划、水平季节规划和管理对策等,对城市景观规划研究领域起到一定的借鉴作用,推动了城市农耕景观的发展,使城市面貌更完善,食品更安全,进而打造我们的美丽中国。     

Effect of High Pressure and 4-Hexylresorcinol on Enzymatic Activity and Darkening in Oysters

ABSTRACT: Oysters treated with and without 4-hexylresorcinol were pressurized (400 MPa/7 °C/10 min) and stored chilled for 21 d, either vacuum-packed or packaged aerobically. The results of visual evaluation of darkening and polyphenoloxidase (PPO) activity levels suggest that during storage, non enzymatic browning occurred 1st, followed by blackening caused by PPO activity. PPO activity did not increase in the vacuum-packed oysters during storage, but pressurization was observed to activate the PPO. Autolytic activity in the oysters increased due to the high-pressure treatment, although higher autolysis levels were recorded in the unpressurized oysters at the end of storage. Inhibition of PPO activity by the 4-hexylresorcinol was observed chiefly in the vacuum-packed batches.     

广州秋季市售生蚝微生物污染状况调查

目的是了解广州秋季市售生蚝微生物污染状况。按照GB／T4789—2003《食品卫生微生物学检验》对样品进行微生物检测,结果发现秋季市售生蚝的微生物污染状况比较严重,菌落总数和大肠菌群指标均出现严重超标,超标率分别达到68％和78％,即使在温度偏低的11月份超标现象仍较严重。所检样品中,弧菌超标更为严重,3个月弧菌的检出率则高达90％。结论是广州市售生蚝的微生物污染状况严重,建议消费者不要生食或使用未煮熟的生蚝。     

Effect of heat pretreatment before isoelectric solubilisation/precipitation on the characteristics of Pacific oyster (Crassostrea hongkongensis) and Antarctic krill (Euphausia superba) protein isolates

Heat treatment is a convenient way to eliminate the effects of endogenous enzymes on the industrial production of stable products. This study describes the preparation of protein isolates from oysters (OPI and HOPI) and krill (KPI and HKPI) by isoelectric solubilisation/precipitation (ISP) with or without heat pretreatment and comparatively presents their characteristics. The results showed that the solubilities of HOPI (24.08 ± 1.94%) and HKPI (42.29 ± 0.78%) were higher than those of OPI (13.46 ± 0.78%) and KPI (21.71.46 ± 1.51%), and the free and total sulphhydryl (-SH) content and surface hydrophobicity of HOPI and HKPI were higher than those of OPI and KPI, which are related to higher fat content of HOPI (10.37 ± 0.55%) and HKPI (34.89 ± 1.19%). SDS–PAGE and gel chromatography pattern results showed that macromolecular proteins were degraded by endogenous enzymes in OPI and KPI, while they remained unaffected in HOPI and HKPI. The FT-IR spectra showed similar patterns between OPI and HOPI and between KPI and HKPI. While the essential amino acid content was similar for OPI and HOPI (47.06 ± 1.33% and 47.93 ± 1.02%), that of KPI and HKPI (50.89 ± 0.89% and 51.19 ± 1.11%, respectively) was not significantly different.