MODIFIED ATMOSPHERE AND VACUUM PACKAGING OF MEAT AND POULTRY PRODUCTS

Extension of the shelf-life of meat and poultry products is one of the technology needs to meet the demands of consumers. In this respect, increasing attention is put on packaging techniques. Modified atmosphere packaging (MAP) and vacuum packaging (VP) are recent innovations that have been gaining importance as preservation techniques to improve the shelf-life of meat and poultry. MAP provides alterations of atmospheric gas concentrations in the pack. Controlled atmosphere (CA) packaging is also MAP, wherein the selected atmospheric concentration of gas is actively maintained throughout the storage period. In VP, air is completely removed. The three principal gases used in MAP are carbon dioxide (to inhibit bacteria and moulds), nitrogen (to avoid oxidation of fats and pack collapse), and oxygen (to prevent anaerobic growth). Retention of meat color is better in MAP than in VP. However, color is regained when meat is removed from VP packets and exposed to air. Microbial profiles of MAP- and VP-meat do not differ significantly. MAP offers several unique advantages for retaining the desirable market quality of products. The safety of MAP meat is still a concern under temperature abuse conditions but it can be improved by coupling with hurdle technology and proper preservation systems. Active packaging is a significant area of advancement of MAP technology to further improve the safety of meat and poultry products. This contribution critically reviews the existing knowledge on MAP and VP of meat and poultry in order to broaden our understanding of the subject and to suggest further areas of research to effectively use these technologies for marketing safe meat and poultry products.     

MODIFIED ATMOSPHERE AND VACUUM PACKAGING OF MEAT AND POULTRY PRODUCTS

Extension of the shelf-life of meat and poultry products is one of the technology needs to meet the demands of consumers. In this respect, increasing attention is put on packaging techniques. Modified atmosphere packaging (MAP) and vacuum packaging (VP) are recent innovations that have been gaining importance as preservation techniques to improve the shelf-life of meat and poultry. MAP provides alterations of atmospheric gas concentrations in the pack. Controlled atmosphere (CA) packaging is also MAP, wherein the selected atmospheric concentration of gas is actively maintained throughout the storage period. In VP, air is completely removed. The three principal gases used in MAP are carbon dioxide (to inhibit bacteria and moulds), nitrogen (to avoid oxidation of fats and pack collapse), and oxygen (to prevent anaerobic growth). Retention of meat color is better in MAP than in VP. However, color is regained when meat is removed from VP packets and exposed to air. Microbial profiles of MAP- and VP-meat do not differ significantly. MAP offers several unique advantages for retaining the desirable market quality of products. The safety of MAP meat is still a concern under temperature abuse conditions but it can be improved by coupling with hurdle technology and proper preservation systems. Active packaging is a significant area of advancement of MAP technology to further improve the safety of meat and poultry products. This contribution critically reviews the existing knowledge on MAP and VP of meat and poultry in order to broaden our understanding of the subject and to suggest further areas of research to effectively use these technologies for marketing safe meat and poultry products.     

壳聚糖在果品贮藏保鲜中的应用进展

综述了目前壳聚糖在果品贮藏保鲜中的应用研究情况.这些研究表明:壳聚糖涂膜可有效地延长果品的商品期;涂膜的浓度及厚度要适宜.不同类型的果品,其涂膜的浓度及厚度不尽相同.同时也对壳聚糖的贮藏保鲜机理进行了简单的阐述.     

天然复合果蔬汁饮料的研制

以色彩一致，营养丰富的苹果、草莓、胡萝卜、番茄为原料制成复合果蔬汁饮料，经正交试验法得出最佳工艺参数，为天然复合果蔬汁饮料的进一步开发与研究提供了科学的依据。     

罗汉果的保健功能及产品开发

概述了罗汉果的营养成分、保健功能,并对一些已有的罗汉果产品作了介绍,提出了综合开发利用罗汉果的思路.     

Nisin及其在果蔬制品中的应用

Nisin是一种新型天然食品防腐、保鲜剂，它是目前世界上唯一允许使用在食品防腐方面的抗菌素。本文综述了Nisin的结构、性质、作用机理等，并论述其在蔬菜制品上的应用。     

THE DEVELOPMENT OF A RISK ASSESSMENT MODEL FOR USE IN THE POULTRY INDUSTRY

A simulation model that assesses the risk of acquiring salmonellosis from consumption and handling of chicken was created in an Excel ™ spreadsheet and was simulated using Risk ™. The model simulated the distribution, preparation, and consumption of 1,000 chickens and was designed to determine the relationship between the level of Salmonella contamination on chickens at the processing plant exit and the risk of salmonellosis for consumers of the chickens. A scatter plot of the probability of acquiring salmonellosis from consumption of the chickens simulated versus the Salmonella load on the chickens at the processing plant exit clearly showed that highly (i.e., > 100 Salmonella/ bird) contaminated chickens at the plant exit did not necessarily pose greater risk of salmonellosis than lightly (i.e., < 10 Salmonella/ bird) contaminated chickens at the plant exit. Rather, greater risk of salmonellosis was realized from lightly contaminated chickens when they were temperature-abused, undercooked, and consumed by someone from the high risk population.     

果蔬保鲜膜的保鲜机理与研究进展

综述果蔬保鲜膜的保鲜机理,介绍果蔬保鲜膜先后出现的硅窗调气薄膜、微孔果蔬保鲜膜、可食性果蔬保鲜膜、抗菌保鲜膜的主要性能、特点及其应用现状,并简要分析果蔬保鲜膜今后的发展趋势。     

腈纶生产形势与新产品开发

回顾了我国腈给新产品开发的历史现状．分析了目前国内腈纶生产的形势及面临国际市场的冲击，并指出开发腈纶新产品的急迫性．     

纺粘法非织造布生产技术改造及产品开发

简介了聚丙烯纺粘法非织造布的生产工艺，讨论了诸如纺丝温度、侧吹风、 牵伸风、泵供量、摆丝幅度、摆丝频率以及压延机热压合温度和压力等对纺粘法非 织造布质量的影响，并介绍了该厂设备幅宽改造、边角料回收系统改造、节电改造 以及产品开发的情况。     

USE OF TIME/TEMPERATURE INTEGRATORS, PREDICTIVE MICROBIOLOGY, AND RELATED TECHNOLOGIES FOR ASSESSING THE EXTENT AND IMPACT OF TEMPERATURE ABUSE ON MEAT AND POULTRY PRODUCTS

Temperature abuse is a main concern for chilled and/or MAP meat and poultry products since it will not only cause economic loss, but may also lead to a foodborne illness hazard. A major question for such products is whether organoleptic spoilage due to microbial or chemical action will occur before pathogen numbers or toxin levels become a risk when a product undergoes abuse temperatures. Time-temperature integrators (TTI) have shown potential to indicate or estimate temperature abuse. However knowledge of predictive food microbiology is needed for each food to employ a TTI tag. The simple Monod and the nonlinear Gompertz function can be used to obtain growth parameters (i.e., lag time, exponential growth rate) from kinetic studies of microbial spoilage. The temperature dependence of these parameters is best evaluated by the Arrhenius or the square root model. Effects of temperature on other deteriorative processes can also be described similarly. Three approaches are presented to evaluate the extent and impact of temperature abuse on meat and poultry by use of TTI tags, which include the effective temperature, the equivalent time and the equivalent point approach. Other technologies to evaluate or to reduce the impact of temperature abuse are also discussed .