原料肉质量对冷却肉贮藏性的影响

选取6种不同来源的猪肉,均采用保鲜剂处理并使用PE／PA塑料袋真空包装,研究其在0～4℃冷却保存条件下的保鲜效果。对各组肉样进行感官评定,测定其TVB—N值、菌落总数,并进行球蛋白沉淀试验,从而判定样品的新鲜度的变化。前15d每3天评定一次,15d后每天评定一次。结果表明：肉的质量越好其贮藏性越好。     

Application of biopreservatives in meat preservation: a review

As a highly perishable food, raw meat, if not preserved, will spoil due to the altered metabolism, microbial activity and external factors during storage. Biopreservatives, as a new type of preservatives, are characterised by nontoxicity, extensive source and good application prospects in the raw meat. This review discusses the factors responsible for the spoilage of raw meat, recaps the spoilage bacteria in the raw meat and summarises the major antibacterial mechanism of various biopreservatives. Moreover, application of various biopreservatives in the preservation of raw meat is emphatically reviewed. In addition, some existing challenges for application of biopreservatives and their prospective development are also discussed. The present work provides a theoretical reference for application of various biopreservatives in different types of raw meat for shelf life extension.     

室温下化学法激活乳过氧化物酶体系对原料乳品质的影响

本文对化学法激活乳过氧化物酶体系用于室温下原料乳保鲜进行了研究。研究结果表明,在25℃贮藏温度下,原料奶的货架期随着SCN-和H2O2的浓度增加而增加。对照组和实验组0.1mmol/L,0.25mmol/L,0.5mmol/L的保鲜期分别为19h,19.5h,21.5h和23.5h。在贮藏期间,所有的实验组的微生物数量均低于对照组。11.5h时,激活剂浓度为0.25mmol/L和0.5mmol/L的原料乳的菌落总数比对照组提高了3个卫生等级。在14h时,激活剂浓度为0.25mmol/L和0.5mmol/L的实验组比对照组的大肠菌群数分别低1.2和1.75个对数周期。     

冻藏时间对不同种类原料肉理化特性的影响

以猪肉、鸡肉为研究对象,在-18℃冻藏不同时间(0,1,2,4,8周)后,对原料肉色泽、系水力(失水率和系水率)、蒸煮损失率、pH值、氨基酸以及游离脂肪酸组成进行测定.结果表明:随着冻藏时间增加,原料肉失水率与蒸煮损失率显著升高(P<0.05);系水率显著下降(P<0.05).随贮藏时间延长,原料肉中赖氨酸、丙氨酸和半...     

美洲雁肉常温真空复合保鲜效果的研究

采用醋酸、姜汁和抗坏血酸(VC)3种保鲜剂处理鲜雁肉,再结合真空包装,研究常温下各种保鲜剂对雁肉的保鲜效果,并以不同配比的保鲜剂进行组合,进行正交实验,以肉样感官评价、TVB-N含量和菌落总数为评价指标,优选出保鲜效果最佳的复合保鲜剂。实验结果表明:复合保鲜剂使用效果优于单一保鲜剂,0.4%醋酸+6%姜汁+1%抗坏血酸的复合保鲜剂保鲜效果最佳,常温下可使美洲雁肉保质期达11d。     

低温储存期间原料乳微生物预测模型建立

本研究对秋季低温储存原料乳进行预测微生物学研究。使用Gompertz模型建立4~14℃储存的秋季原料乳中总菌落和嗜冷菌的生长动力模型。模型可以有效的模拟秋季原料乳中微生物的生长情况,模型的相关系数均大于0.972,可以用来预测微生物生长情况和达到控制下限的时间。研究表明嗜冷菌是低温储存的原料乳中优势微生物,在4~8℃储存温度下总菌落数与嗜冷菌的数量呈很好的相关性(R~2=0.931),可以通过总菌数推算出嗜冷菌的数量,保证乳制品的品质。      

辣椒籽油对肉糜低温贮藏特性的影响

为探讨辣椒籽油对猪肉肉糜的保鲜效果,研究了辣椒籽油添加及不同包装方式对猪肉肉糜在4℃低温贮藏条件下的质构、色差、保水性、挥发性盐基氮、TBARS值、菌落总数等指标的影响。结果表明:辣椒籽油的添加使肉糜的红度值提高了2倍,且对肉糜的pH、硬度都有积极影响,辣椒籽油与真空包装结合使用使肉糜的脂肪氧化、蛋白氧化变缓。贮藏第9天对照组TBARS值已达到1.95mg/kg,辣椒籽油组仅1.39mg/kg;对照组TVB-N值达到28.7 mg/100g,辣椒籽油组仅16.8mg/100g。在辣椒籽油和真空包装的联合作用下可有效延长肉糜保质期2d以上。     

Determination of changes occurred in the microflora of cig kofte (raw meat balls) at different storage temperatures

The aim of this study was to investigate the effect of different storage temperatures on the microbiological characteristics and pH values of cig kofte during storage. Storage temperature affected significantly total aerobic mesophilic bacteria (TAMB), coliforms, yeasts and moulds, lactic acid bacteria (LAB) and Staphylococcus aureus counts of cig kofte which had lower counts in refrigerator storage than in room storage following sixth hour for TAMB (P < 0.001), coliform (P < 0.01, P < 0.001), S. aureus (P < 0.01, P < 0.001) and LAB (P < 0.001) and at the end of storage for yeasts and moulds (P < 0.001). Listeria and Salmonella spp. could not be detected at both refrigerator temperature and room temperature storage. In order to minimise the contamination level of cig kofte, use of best microbial quality minced meat and ingredients as well as good personnel hygiene is required and preserved. In addition, Cig kofte should be kept in refrigerator when leftovers remain for additional meals.     

Improved species identification of raw meat by double sandwich enzyme-linked immunosorbent assay

An improved enzyme-linked immunosorbent assay (ELISA) has been developed to enable differentiation of unprocessed beef, sheep, horse, kangaroo, pig, camel, buffalo and goat meats to less than 1% level of detection. This double sandwich system utilises species-specific capture antibodies raised in sheep or cattle and coated on to microtitre plates. Antibody coated plates are then used to immunoextract soluble protein from prepared meat samples. Bound meat proteins are detected by the addition of species-specific rabbit antisera followed by staphyloccocal Protein A conjugated to horse-radish peroxidase (HRPO), or by antisera directly conjugated to HRPO. Adoption of a capture antibody provides a number of advantages over previously described ELISA systems. Sample preparation is not critical because colour production is approximately constant between sample dilutions of 1000 and 10 g litre^?1. Increased sensitivity and selectivity allows the bulking of samples for screening purposes. In addition, the assay is faster; testing may be carried out in less than 2 h.     

低温贮藏过程中水牛肉蛋白质的变化

目的:探明低温贮藏过程中水牛肉蛋白质的变化规律.方法:以水牛肉为研究对象,分别将肉样于4,-18,-60℃贮藏,测定贮藏过程中水牛肉的总蛋白质含量、表面疏水性、总巯基含量、游离巯基含量及羰基值,并对蛋白质指标之间的相关性进行分析.结果:不同低温贮藏过程中,随着贮藏时间的延长,水牛肉的总蛋白质、总巯基、游离巯基含量呈不断...     

A microbiological perspective of raw milk preserved at room temperature using hyperbaric storage compared to refrigerated storage

The effects of hyperbaric storage (HS, 50–100 MPa) at room temperature (RT) on endogenous and inoculated pathogenic surrogate vegetative bacteria (Escherichia coli, Listeria innocua), pathogenic Salmonella enterica and bacterial spores (Bacillus subtilis) were assessed and compared with conventional refrigeration at atmospheric pressure for 60 days. Milk stored at atmospheric pressure and refrigeration quickly surpassed the acceptable microbiological limit within 7 days of storage, regarding endogenous microbiota, yet 50 MPa/RT slowed down microbial growth, resulting in raw milk spoilage after 28 days, while a significant microbial inactivation occurred under 75–100 MPa (around 4 log units), to counts below 1 log CFU/mL throughout storage, similar to what was observed for B. subtilis endospores. While inoculated microorganisms had a gradually counts reduction in all HS conditions. Results indicate that HS can not only result in the extension of milk shelf-life but is also able to enhance its safety and subsequent quality.Industrial relevanceThis new preservation methodology could be implemented in the dairy farm storage tanks, or during milk transportation for further processing, allowing a better microbial control, than refrigeration. This methodology is very promising, and can improve food products shelf-life with a considerable lower carbon foot-print than refrigeration.     

Antimicrobial packaging of raw beef,pork and turkey using silver‐zeolite incorporated into the material

This study determined the efficacy of silver‐zeolite impregnated into wrapping paper to reduce the bacterial growth on raw beef, pork and turkey cuts. This was compared with that of regular butcher paper. The samples were inoculated with Pseudomonas putida (psychrotrophic spoilage bacterium) and stored on 4% silver‐zeolite and regular butcher paper for up to 4 days at 4 °C and 10 °C. Results showed that P. putida on the beef, pork and turkey samples did not increase in numbers after exposure to all paper packaging at 4 °C during the 4 days of storage. At 10 °C storage temperature, logarithmic growth patterns for the organisms were seen on all paper packaging. However, the growth rate was slower for the organisms on the silver‐zeolite paper. Storage on the silver‐zeolite paper accounted for one log cfu/sample mean reduction in viable cell count for the beef, pork and turkey samples when compared with the samples stored on the butcher paper at 3 days.     

原料肉中磷酸盐本底含量状况调查与分析

运用比色法,先后对5类1353个生肉样品、5类121个副产品样品,共计1474个原料肉样品进行了磷酸盐本底含量的测定。结果表明,原料肉中磷酸盐本底含量范围为1.49～16.5g/kg,多数处于低端水平;不同种类的生肉中磷酸盐含量存在显著差异(P<0.05),其中生猪肉中磷酸盐含量最高,其次为鸭肉,生羊肉中磷酸盐含量最低;不同种类的副产物中磷酸盐含量存在显著差异(P<0.05),其中生猪肝中磷酸盐含量最高,其次为生牛肝,生猪肠、肺中磷酸盐含量最低。     

Conventional freezing plus high pressure-low temperature treatment: Physical properties, microbial quality and storage stability of beef meat

Meat high-hydrostatic pressure treatment causes severe decolouration, preventing its commercialisation due to consumer rejection. Novel procedures involving product freezing plus low-temperature pressure processing are here investigated. Room temperature (20 °C) pressurisation (650 MPa/10 min) and air blast freezing (−30 °C) are compared to air blast freezing plus high pressure at subzero temperature (−35 °C) in terms of drip loss, expressible moisture, shear force, colour, microbial quality and storage stability of fresh and salt-added beef samples (Longissimus dorsi muscle). The latter treatment induced solid water transitions among ice phases. Fresh beef high pressure treatment (650 MPa/20 °C/10 min) increased significantly expressible moisture while it decreased in pressurised (650 MPa/−35 °C/10 min) frozen beef. Salt addition reduced high pressure-induced water loss. Treatments studied did not change fresh or salt-added samples shear force. Frozen beef pressurised at low temperature showed L, a and b values after thawing close to fresh samples. However, these samples in frozen state, presented chromatic parameters similar to unfrozen beef pressurised at room temperature. Apparently, freezing protects meat against pressure colour deterioration, fresh colour being recovered after thawing. High pressure processing (20 °C or −35 °C) was very effective reducing aerobic total (2-log₁₀ cycles) and lactic acid bacteria counts (2.4-log₁₀ cycles), in fresh and salt-added samples. Frozen + pressurised beef stored at −18 °C during 45 days recovered its original colour after thawing, similarly to just-treated samples while their counts remain below detection limits during storage.     

贮藏温度对芙蓉李采后保鲜效果的影响

目的研究室温和低温贮藏对芙蓉李果实采后保鲜效果的影响,为芙蓉李果实采后贮藏保鲜技术提供理论基础依据。方法以室温为对照,测定采后贮藏期间各项理化指标变化来评价不同温度对芙蓉李果实采后保鲜效果的影响。结果低温贮藏可有效抑制芙蓉李果实采后贮藏期间腐烂率和失重率上升,延缓果实硬度下降、可滴定酸含量下降和丙二醛含量的积累。结论低温贮藏可提高芙蓉李采后保鲜效果。     

可食性包装在冷却肉保鲜中的应用

系统阐述可食性包装的特点以及在冷却肉保鲜中的应用。介绍可食性包装减少冷却肉中水分和汁液损失,抑制油脂氧化和微生物生长繁殖,以及提高冷却肉品质和延长其货架期的研究进展,并提出目前可食性包装应用中存在的问题。