安全包装有效延长货架期保障鲜奶品质

众所周知,牛奶是非常容易被污染、易变质的敏感高营养品,如何尽量的减少牛奶中的细菌总量又同时最大限度的保护牛奶中原来的营养,是全世界乳品企业一直努力的方向。     

Individual Packaging of Apples for Shelf Life Extension

Red Delicious apples after 2 wk and 4 months of cold storage and after 4 months of CA storage were individually packaged in two heat-shrinkable copolymers. Packaged and control apples were stored at 3°C and 90% RH, 21°C and 30°C and 50% RH, and at 30°C and 50% and 70% RH and the effect of packaging on modification of the microatmosphere inside the fruit and on various chemical and physiological changes were monitored with time. Temperature was the dominant storage factor. At 3°C, packaged and control apples had good eating quality and did not show significant differences (P > 0.05) after 3 months of storage. At 21°C, packaged apples reached a minimum acceptable condition at week 6 of storage which represented a shelf life extension of 3-4 wk over nonpackaged controls. At 30°C, internal quality of packaged apples deteriorated faster than controls. The respiration rate of packaged apples was lower than that of controls.     

Combined Application of Antibrowning,Heat Treatment and Modified‐Atmosphere Packaging to Extend the Shelf Life of Fresh‐Cut Lotus Root

This work aimed to determine the effects of different concentrations of antibrowning treatments (that is, distilled water [DW], 1% ascorbic acid [AA], 0.5% chamomile [CM], and 1% AA + 0.5% CM) and heat‐treatment (55 °C for 45 s) combined with packaging under 4 different modified‐atmosphere gas compositions (that is, air, vacuum, 100% CO₂, 50% CO₂/50% N₂) on the quality and microbiological characteristics of fresh‐cut lotus root. The quality characteristics (that is, color, weight loss, texture, pH, polyphenoloxidase activity, and total phenolic content) of the AA + CM‐dipped sample in 100% CO₂ packaging were maintained significantly better than those of the other samples (P < 0.05). The microbiological counts observed in the DW‐dipped sample during storage were higher than those of the AA, CM, and AA + CM samples, and heat‐treatment retarded the microbiological deterioration of fresh‐cut lotus root. Therefore, the results revealed that dipping in an antibrowning treatment (AA + CM), and 100% CO₂ MAP with heat treatment effectively extend the shelf life of fresh‐cut lotus root to 21 d at 5 °C.     

Antimicrobial and Antioxidative Strategies to Reduce Pathogens and Extend the Shelf Life of Fresh Red Meats

Abstract: The shelf life of packaged fresh red meats is most frequently determined by the activity of microorganisms, which results in the development of off‐odors, gas, and slime, but it is also influenced by biochemical factors such as lipid radical chain and pigment oxidation causing undesirable flavors and surface discoloration. The predominant bacteria associated with spoilage of refrigerated meats are Pseudomonas, Acinetobacter/Moraxella (Psychrobacter), Shewanella putrefaciens, lactic acid bacteria, Enterobacteriaceae, and Brochothrix thermosphacta. The spoilage potential of these organisms and factors influencing their impact on meat quality are discussed. High O₂‐modified atmosphere (80% O₂+ 20% CO₂) packaging (MAP) is commonly used for meat retail display but vacuum packaging remains the major MAP method used for meat distribution. Two‐step master packaging (outer anoxic‐20% CO₂+ 80% N₂/inner gas‐permeable film) is used for centralized MAP distribution, but CO use (0.4%) in low O₂ packaging systems is limited by consumer uncertainty that CO may mask spoilage. Active packaging where the film contributes more than a gas/physical barrier is an important technology and has been studied widely. Its application in combination with MAP is very promising but impediments remain to its widespread industrial use. The influence of processing technologies including modified atmospheres on lipid oxidation and discoloration of meats are analyzed. Because both organic acids and antioxidants have been evaluated for their effects on microorganism growth, in concert with the prevention of lipid oxidation, work in this area is examined.     

乳制品企业：不可觑视的“着装”选择

随着人们生活水平的提高，乳品以其营养丰富且易被人体消化吸收的特点，逐渐成为人们日常生活不可或缺的食品之一。虽然目前中国牛奶的人均年平均消耗量只占世界平均水平的1/10，中国人均奶业占有量超过10千克，总产量1350万吨，但是到2030年，人均奶类占有量将达到25千克，总产量可达到4250万吨，其中液态奶的消费量正以30%的幅度递增，     

Apple Wraps: A Novel Method to Improve the Quality and Extend the Shelf Life of Fresh-cut Apples

A novel method was developed to extend the shelf life and improve the quality of fresh-cut produce. Edible coatings and films were made from apple puree with various concentrations of fatty acids, fatty alcohols, beeswax, and vegetable oil. Apple pieces were coated with solutions or wrapped in preformed films. Changes in moisture content and color were measured during storage. Increasing concentrations of lipids significantly improved the moisture barrier properties of films. Water vapor permeability varied from 69 to 325 g mm/kPa d m². Apple-based wraps significantly reduced moisture loss and browning in fresh-cut apples. Color was preserved for 12 d at 5 °C. Wraps were significantly more effective than coatings.     

Shelf Life of Mature Green Tomatoes Stored in Controlled Atmosphere and High Humidity

Freshly harvested mature green tomatoes were washed, sorted and treated with 125 ppm chlorine water. The treated tomatoes were stored at 85% or 98% RH under controlled atmosphere (CA) storage for periods up to 8 wk. The controlled atmosphere was 2.5% O₂, 5.0% CO₂, and N₂ as the balance gas at 12°C. After storing 40 days, the tomatoes were allowed to ripen in air at 23°C. Samples of tomatoes were tested every 3 days to examine changes in quality as determined by visual observation, weight loss, titratable acidity, pH, color and firmness. Weight loss was reduced significantly by CA storage of tomatoes at 98% RH. Tomatoes remained green up to 40 days of storage and changed in color gradually during consecutive storage in atmospheric conditions. Appearance of the tomatoes was acceptable after ripening.     

Use of Carbon Monoxide Packaging for Improving the Shelf Life of Pork

ABSTRACT: Effects of carbon monoxide in modified-atmosphere packaging (MAP-CO) for pork were investigated. Eighty pork loins (40 injected, 40 uninjected) were used to evaluate color, microbial growth, rancidity, purge, and sensory quality of pork chops in 4 packaging environments (aerobic-overwrap, vacuum, MAP without CO, and MAP-CO). Treatments were evaluated during 36 d of refrigerated storage. Overall Hunter a values were significantly ( P < 0.001) greater in MAP-CO (11.25) than aerobic (6.93) packages. Sensory color values (100 point scale) were also greater for chops in MAP-CO (85.91) than aerobic (62.47) packages. However, MAP-CO did not reduce purge loss. Results showed that CO significantly improved color stability and sensory panel scores for both injected and noninjected pork chops.     

Packaging of Olive Oil: Quality Issues and Shelf Life Predictions

Olive oil has gained much appreciation among consumers worldwide leading to increased markets as well as greater consumer expectation and thus more challenges for the relevant food sector. By understanding the product, its interactions with the environment, and the protective role of the package, decisions can be made on the barrier properties required of the packaging materials to achieve the desired shelf life. To this end, the shelf life of packaged olive oil under various storage and distribution environments can be predicted by mathematical modeling. This review examines the basic factors affecting the shelf life of olive oil in different packaging systems and describes the main oxidative degradation mechanisms for them. Since an experimental investigation to correlate the basic quality factors and the shelf life of a product is time- and effort-consuming, the use of mathematical modeling for the prediction of packaged olive oil shelf life is also discussed. In the presented works, shelf life predictions were based on the most consumer-related attributes; namely, the evolution of olive oil flavor compounds under various packaging and storage conditions. The validation of the simulations against known experimental results showed a very good correlation, confirming the value of the mathematical approach for a quick and accurate prediction of shelf life of oxidation-sensitive products.     

Packaging of Olive Oil: Quality Issues and Shelf Life Predictions

Olive oil has gained much appreciation among consumers worldwide leading to increased markets as well as greater consumer expectation and thus more challenges for the relevant food sector. By understanding the product, its interactions with the environment, and the protective role of the package, decisions can be made on the barrier properties required of the packaging materials to achieve the desired shelf life. To this end, the shelf life of packaged olive oil under various storage and distribution environments can be predicted by mathematical modeling. This review examines the basic factors affecting the shelf life of olive oil in different packaging systems and describes the main oxidative degradation mechanisms for them. Since an experimental investigation to correlate the basic quality factors and the shelf life of a product is time- and effort-consuming, the use of mathematical modeling for the prediction of packaged olive oil shelf life is also discussed. In the presented works, shelf life predictions were based on the most consumer-related attributes; namely, the evolution of olive oil flavor compounds under various packaging and storage conditions. The validation of the simulations against known experimental results showed a very good correlation, confirming the value of the mathematical approach for a quick and accurate prediction of shelf life of oxidation-sensitive products.     

包装方式对糌粑粉贮藏品质及货架期的影响

为明确糌粑粉的货架期品质变化情况,本文分别对糌粑粉进行普通包装、铝箔包装、添加抗氧化物的普通包装、添加抗氧化物的铝箔包装、添加脱氧剂的普通包装和添加脱氧剂的铝箔包装这六种方式的处理,通过采用50 ℃条件下进行货架期加速实验,对不同包装方式的糌粑粉的感官评价、氧化品质和挥发性成分进行分析。结果表明:随着贮藏时间延长,糌粑粉品质发生氧化劣变,哈败味增加,脂肪酸值和丙二醛值分别从初始的14.17 mg KOH/100 g和0.402 mg/kg增长至20 d后的39.86 mg KOH/100 g和1.388 mg/kg;在风味组成中,烷烃类物质随贮藏时间延长而减少,酸类物质的含量升高。对比包装方式和添加剂效果发现,铝箔包装均优于普通包装,脱氧剂效果优于抗氧化物,其脂肪酸值、丙二醛值的增长速率均有所减缓。进一步预测常温条件下6种糌粑粉货架期从长到短依次为:添加脱氧剂的铝箔包装（208 d）、添加抗氧化物的铝箔包装（172 d）、铝箔包装（160 d）、添加脱氧剂的普通包装（148 d）、添加抗氧化物的普通包装（136 d）、普通包装（116 d）。这一研究明确了糌粑粉的货架期品质变化情况,为实现糌粑的工业化生产提供技术支持。     

气调包装果蔬贮藏寿命预测

在分析气调包装果蔬生理特性的基础上,提出以干物质的分解量作为果蔬产品质量的控制指标,结合气调包装气体交换机理及包装内气体浓度的变化,建立气调包装果蔬的贮藏寿命预测模型。并对一樱桃果品气调包装进行其贮藏寿命的预测。     

瓶装材料对核桃油品质及预测货架期的影响

为探究不同瓶装材料对核桃油品质变化的影响,分别用敞口玻璃烧杯、马口铁罐、玻璃油瓶盛装核桃油,采用Schaal烘箱法加速油脂氧化,以过氧化值、酸值、脂肪酸组成、驰豫特性为评价指标,研究不同瓶装材料对核桃油氧化稳定性及预测货架期的影响。结果表明,以过氧化值≤0.25 g/100 g为限量值时（植物油国家标准规定）,添加特丁基对苯二酚（TBHQ）的烧杯、马口铁罐、玻璃油瓶盛装核桃油和空白对照的预测货架期分别为160、112、336和64 d,在预测货架期内,核桃油酸价均在二级核桃油要求范围内。3种包装材料对添加TBHQ的核桃油氧化稳定性强弱顺序为：玻璃油瓶>烧杯>马口铁罐;核桃油长期贮藏建议以玻璃油瓶盛装为佳。     

如何延长齿楔带的使用寿命

就齿楔带在磨粉机传动系统的应用，从设计、制造到日常的调整、维护，详细论述了延长齿楔带使用寿命的几个方法。     

An Integrated Approach to Factors Affecting the Shelf Life of Products in Modified Atmosphere Packaging (MAP)

Abstract

The aim of this work was to analyze the main factors influencing the shelf life of peanut products in modified atmosphere packaging (MAP). Roasted and salted peanuts produced by three well-known commercial companies were presented as examples. Different types of packaging (multilayer laminated materials, cans) with different gas mixture composition (0–1% O₂, 1–3% O_2, 3–6% O₂) were compared. The main aim of shelf-life investigation is to ensure consumer acceptance of a product. Factors affecting the shelf life of products in MAP are presented as an integrated pyramid. All elements of this shelf-life pyramid should be analyzed and included during shelf-life investigations. This study indicates that estimation of the shelf life of a food is integrally related to its packaging (e.g., peanuts in MAP); both product conditions and the package as well as gas mixture composition should be considered.     

An Integrated Approach to Factors Affecting the Shelf Life of Products in Modified Atmosphere Packaging (MAP)

The aim of this work was to analyze the main factors influencing the shelf life of peanut products in modified atmosphere packaging (MAP). Roasted and salted peanuts produced by three well-known commercial companies were presented as examples. Different types of packaging (multilayer laminated materials, cans) with different gas mixture composition (0-1% O₂, 1-3% O_2, 3-6% O₂) were compared. The main aim of shelf-life investigation is to ensure consumer acceptance of a product. Factors affecting the shelf life of products in MAP are presented as an integrated pyramid. All elements of this shelf-life pyramid should be analyzed and included during shelf-life investigations. This study indicates that estimation of the shelf life of a food is integrally related to its packaging (e.g., peanuts in MAP); both product conditions and the package as well as gas mixture composition should be considered.     

Active Modified Atmosphere Packaging of Fresh Fruits and Vegetables: Modeling with Tomatoes and Oxygen Absorber

Design of active modified atmosphere packaging for vegetables was studied by developing a mathematical model predicting gas changes and based on the following independently evaluated parameters: vegetable respiration rate, film permeability, and oxygen absorption kinetic of the absorber. A step‐by‐step model validation was performed on a tomatoes/low‐density polyethylene pouch/commercial iron‐based scavenger system at 20 °C. Without optimization, the model fit experimental data with root mean square error (RMSE) value lower than 1.5. Oxygen absorbers had a strong influence on transient period characteristics by reducing their duration (50 and 100 h with and without absorber, respectively) and suppression of the CO₂ peak owing to a rapid oxygen depletion.