充氮包装下榛子品质变化的动力学建模

探索了不同包装方式对榛子品质变化的影响,结果表明充氮包装保鲜效果最好。建立了充氮包装下酸价、过氧化值随贮藏温度和时间变化的动力学模型,以控制榛子在贮藏过程中的品质和货架期。结果表明,随着贮藏时间的延长和贮藏温度的升高,榛子的酸价和过氧化值不断增加,普通包装增加最快,充氮包装由于良好的保鲜性能而增长较慢。酸价、过氧化值对一级化学反应模型和Arrhenius方程具有很高的拟合精度。     

常温下MAP对红松仁酸价的影响

研究常温下MAP对红松籽油酸价的影响,为松仁的科学贮藏提供技术参考。研究结果表明MAP可以较好地抑制松仁的酸败,有利于保持松仁的贮藏品质,其中充入100%N2和100%CO2气体的试样在贮藏期间其酸价的变化相对一致,效果相对其他充气方式较好,建议在常温贮藏中使用。     

坚果酸败的包装控制方法

坚果中富含油脂和蛋白质,易在氧气、光照等因素下酸败变质采用合适的包装技术,如高阻隔包装材料、真空包装、充氮包装、添加脱氧剂等,能有效的控制坚果酸败进程。同时,配合专业的包装检测技术加强如氧气透过率、密封性、氮气透过率等重点指标监测,能很大程度上避免保质期内坚果酸败的发生。     

包装方式对留胚米品质的影响

目的 研究在3种贮藏温度条件下,4种包装方式对留胚米品质的影响。方法 以实验室自制留胚米（留胚率为85%）为实验材料,选用同一种包装材料,分别采用普通包装、真空包装、充CO2包装和充N2包装等4种方式,并在3种不同温度（5,25,35 ℃）条件下贮藏,以感官品质、含水率和脂肪酸含量为评价指标,定期抽样测量各指标的变化规律。结果 各种包装方式下的留胚米感官品质均随贮藏时间的增加而降低,含水率随贮藏时间的增加呈现先增加后降低的规律,脂肪酸含量随贮藏时间的增加而增加。普通包装的留胚米在5,25,35 ℃下贮藏的保质期分别为45,30,15 d;真空包装的留胚米在5 ℃下贮藏的保质期大于120 d,在25 ℃和35 ℃下贮藏的保质期分别为105 d和90 d;充CO2包装的留胚米在5 ℃和25 ℃下贮藏的保质期为90 d,在35 ℃下贮藏的保质期为60 d;充N2包装的留胚米在5,25,35 ℃下贮藏的保质期分别为90,75,60 d。结论 真空包装为最适宜的包装方式,其次为充CO2包装和充N2包装,普通包装方式的留胚米保质期相对最短。     

干砸、湿砸工艺对核桃仁品质的影响

核桃在我国广大地区种植,因其极大的食用和药用价值,成为我国重要经济作物之一。但由于核桃富含油脂,其果仁在贮藏过程中极易因为外界因素而发生酸败变质,导致其品质下降,甚至产生有害物质。本文以"晋龙1号"这一核桃品种为主要试验材料,通过研究干砸、湿砸两种不同去壳工艺处理的核桃仁,在贮藏条件相同情况下(室温25±1℃),其脂肪含量、酸价、过氧化值、SOD值、脂肪酶活性等生理生化指标的变化,找出经过干砸、湿砸去壳工艺处理的核桃仁氧化酸败与抗氧化物质的关联,了解核桃仁油脂氧化酸败的机理。     

包装方式对青少年型挤压强化米品质的影响

目的研究不同包装方式对挤压营养强化米品质的影响。方法以实验室自制的青少年型挤压营养强化米为对象,分别以马口铁罐装、真空包装和普通袋装3种方式进行包装贮存,并在不同的贮存条件(4℃,室温,37℃)下贮存180 d,考察样品的维生素、水分、酸价的变化规律。结果不同的包装方式对青少年型挤压营养强化米的水分、酸价及维生素都有不同程度的影响。结论罐装和真空包装方式更能保持样品的营养品质。     

包装材料透氧性对蛋糕油脂氧化程度的影响研究

分别采用KNY/CPP,OPP/VMCPP和PET(SiO2)/CPP 3种材料对蛋糕进行包装,研究了3种包装材料透氧性对蛋糕油脂氧化程度的影响,并对包装材料下的氧化速率进行了表征,分别得到了3种包装材料酸价氧化速率拟合方程和过氧化值氧化速率拟合方程,证实了包装材料的透氧率与蛋糕的油脂氧化速率不能建立明确的数学关系。     

膜包装菜籽油光照加速试验的氧化指标研究

评价油脂氧化的指标多样,而对于贮藏在低氧光照环境下的油脂是否适用有待研究。以食用菜籽油为研究对象,用较低透氧率的软塑膜PET12/CPP20包装后,在不同光照强度下进行贮藏实验,测定油脂常用的氧化指标,包括过氧化值、共轭二烯值、共轭三烯值、光敏剂(叶绿素)、挥发性醛类(己醛),以此来确定适用于光照加速试验的氧化指标。结果表明:过氧化值在光照条件下迅速增大,同时光照加速了其降解,导致了过氧化值与光照强度无显著关系;共轭二烯值与共轭三烯值呈波动上升趋势,己醛及光敏剂的含量与光照强度显著相关;中低透氧率膜包装菜籽油的保质期预测应以己醛及光敏剂为主要光氧化指标。     

军用快餐米饭货架寿命加速试验研究

采用食品货架寿命加速试验基本理论与实验方法,以军用快餐米饭的酸价和过氧化值作为评价产品货架寿命的主要因素,得出了采用PET/AL/PA/PE材料包装的军用快餐米饭的酸价和过氧化值,在不同的加速温度下随贮藏时间的变化规律,并建立了相应温度下的货架寿命动力学模型,以预测快餐米饭在贮藏过程中的品质变化和货架寿命.此研究为设计或预测快餐食品包装在不同温度下的货架寿命提供了可靠的理论依据与实验手段.     

不同包装橙汁贮藏期间物理品质的变化

以纸铝塑复合包装、普通PET瓶和充氮PET瓶包装的橙汁为研究对象,监测其物理指标,如褐变度、可溶性固形物、pH值、表观黏度及流变特性,在不同温度下贮藏24周过程中的动态变化。结果表明,试验周期内不同包装橙汁褐变度的变化符合一级动力学模型;橙汁的流体性质均属于假塑性流体;pH值随贮藏时间延长而降低;可溶性固形物含量在4℃和20℃下无显著变化(P0.05),而在37℃和55℃下呈上升趋势。研究表明,纸铝塑复合包装可以保持橙汁物理品质相对稳定,而从节约成本和携带方便等方面考虑,充氮PET瓶仍是较优的包装方式。     

充氮包装技术防护性能研究

为了考察充氮包装技术的防护性能,通过高低温湿热试验,测试了氮气介质与空气介质防护下器材表面的平均腐蚀速率与包装袋内氧含量的变化。结果表明:采用同一外包装材料时,氮气介质防护的平均腐蚀速率远远低于空气介质,其平均腐蚀速率低于NACE RP-0775-91标准中规定的轻度腐蚀一个数量级;充氮包装材料阻隔性能优异,包装袋内氧含量稳定(0.1%)。可见,充氮包装技术能对器材提供较好的防护。     

Effect of chitosan coating and vacuum packaging on the quality of refrigerated grilled pork

The effects of chitosan coating and vacuum packaging on the quality and shelf‐life of retail packaged grilled pork in a PVDC/nylon pouch during refrigerated storage at 2 ± 1°C were investigated. Grilled pork without chitosan coating and packaged in 100% air was used as the control sample. Firmness, pH, colour, peroxide values, microbial population and shelf‐life (as determined by sensory characteristics) of the samples were determined during the storage. The results showed that colour, peroxide values and microbial population coincided with sensory characteristics. The delayed growth of microbes in vacuum packaging can be attributed to inhibition by low levels of O₂. Chitosan coating was shown to minimize oxidation, as reflected by the peroxide values, colour changes and microbial counts of the samples. Vacuum‐packaged chitosan‐coated grilled pork showed negligible microbial growth and was found to be organoleptically acceptable throughout the storage period. Chitosan coating along with vacuum packaging provided a type of active packaging to maintain quality and extend the shelf‐life of grilled pork. Copyright © 2006 John Wiley & Sons, Ltd.     

Effects of active chitosan-flaxseed mucilage-based films on the preservation of minced trout fillets: A comparison among aerobic,vacuum, and modified atmosphere packaging

The objectives of the current study were to examine physical–mechanical, structural, and morphological characteristics of chitosan-flaxseed mucilage films enriched with Ziziphora clinopodioides essential oil (ZEO; 0%, 0.25%, and 0.5%) and sesame oil (SO; 0% and 0.75%) and to provide useful information for the preservation of minced trout fillet's using antimicrobial films under aerobic, vacuum, and modified atmosphere conditions for 16 days. The films showed thickness, tensile strength, puncture force, puncture deformation, water vapor transmission rate, water vapor permeability, swelling index, and oxygen permeability values ranging 0.082–0.86 mm, 33.34–46.83 MPa, 25.69–53.08 N, 11.45–28.45 mm, 17.48–26.73 g/m² h, 8.57–12.49 × 10⁻⁴ g mm/m² h Pa, 12.45–38.43%, and 3.02–13.32 × 10⁻¹² cm³/m² s Pa, respectively. The following order of effect on the microbial spoilage population of treated samples was found in the applied packaging methods: modified atmosphere packaging > vacuum packaging > aerobic packaging. The final microbial population of treated samples was 0.35–4.91 log CFU/g lower than the controls after 16 days of refrigerated storage. At the end of the storage, the total volatile base nitrogen, peroxide value, and thiobarbituric acid reactive substances of untreated samples were 34.02–48.6 mg of N/100 g, 1.43–2.32 meq of peroxide/1000 g, and 3.33–4.24 mg of malondialdehyde/kg, respectively. The lowest corresponding values were recorded for the treated samples with ZEO 0.5% + SO 0.75% films by 14.26–17.73 mg of N/100 g, 0.48–0.86 meq of peroxide/1000 g, and 1.08–1.48 mg of malondialdehyde/kg, respectively.     

真空包装大米贮藏品质影响因素的研究

探讨了不同真空度、环境条件和贮藏时间对大米贮藏品质的影响。选用了市售天津小站大米为研究对象,选定不同真空度对其进行了真空包装,在不同环境条件下进行了模拟贮藏,定期测定了样品中的脂肪酸值、水分和还原糖含量,采用正交设计方法对测定结果进行了分析,确定了影响真空包装大米贮藏品质的主要因素。结果表明,在短期内,真空度是影响大米贮藏品质的最主要因素。     

Changes in the quality of abalone (Haliotis asinina Linnaeus) packaged under atmospheric air,vacuum and modified atmosphere

Changes in the quality of abalone (Haliotis asinina Linnaeus) meat packaged under modified atmosphere (MA) of 40% CO2/30% O2/30% N2, vacuum and atmospheric air in polyvinylidene chloride (PVDC)/nylon/oriented polypropylene (OPP) pouches, and stored at 2 ± 1°C were investigated. Biochemical indices, such as pH, total volatile basic nitrogen (TVB‐N), and trimethylamine (TMA) and sensory evaluation, as well as total plate counts of packaged abalone meat were determined periodically. TMA was not affected by the packaging conditions, and remained low during storage periods. A decrease in pH of the MA packaged abalones during the storage reflected the apparent absorption of CO2. The content of TVB‐N slowly increased in the MA packaged abalone, whereas those stored in atmospheric air markedly increased during the storage. The sensory quality of MA packaged abalones was shown to be acceptable up to 15 days, while atmospheric and vacuum‐packaged abalones were not acceptable after 3 days of storage. Copyright © 2007 John Wiley & Sons, Ltd.     

Effects of PP‐based Nanopackaging on the Overall Quality and Shelf Life of Ready‐to‐eat Salami

A total of 1% nanoclay containing polypropylene (PP)‐nanocomposite and 1% nanoclay plus 5% poly‐beta‐pinene (PβP) containing PP‐active‐nanocomposite materials were produced and tested for packaging of sliced salami. The sliced salami was packaged using both nanofilms and multilayer film of PP/PA/EVOH/PE under vacuum, modified atmosphere packaging under 50% CO₂ and 50% N₂ and air and stored at 4 °C for 90 days. During storage, headspace gas composition; microbial, physical and chemical analyses; and sensory evaluation were performed. The antimicrobial effect of PβP containing nanomaterial was pronounced under vacuum, and no bacterial growth was observed for 75 days. An a* value decreased notably in all applications during storage and preserved best by the multilayered material under vacuum and high CO₂. Thiobarbituric acid reactive substances (TBARS) were 0.63 mg MDA/kg after the processing and gradually increased at all applications during increased storage. TBARS values of all vacuum applications were lower than that of modified atmosphere packaging applications. Rancid taste development was determined by sensory panelists when TBARS values were higher than 0.80 mg MDA/kg on the 90th day. There was no significant moisture loss, and no increase in hardness was determined during the whole storage time. The longest shelf life was 75 days for the sliced salami under vacuum and high CO₂ using the multilayer material. PβP containing nanomaterial provided 50 days of shelf life under vacuum, which is commercially considerable. Copyright © 2017 John Wiley & Sons, Ltd.     

壳聚糖结合脱氢乙酸钠涂膜对槟榔品质的影响

目的以槟榔为实验材料,基于气调贮藏(O2和CO2的体积分数均为4%)技术,探究壳聚糖结合脱氢乙酸钠涂膜对槟榔的保鲜效果。方法采用不同质量分数壳聚糖溶液(0,0.5%,1.0%,1.5%)结合质量浓度为50 mg/L的脱氢乙酸钠对槟榔进行涂膜,测定其在气调贮藏期间对槟榔感官品质、腐烂率、营养品质的影响。结果涂膜后的槟榔各项品质显著优于未涂膜槟榔。结论经壳聚糖(0.5%)/脱氢乙酸钠(50 mg/L)涂膜后的槟榔在贮藏期30 d内能保持良好的品质,能延缓果皮变黄。     

二氧化硫缓释杀菌包装在“夏黑”葡萄保鲜中的应用研究

目的延长"夏黑"葡萄在常温条件下的货架期。方法以裸放和普通LDPE包装作为参照组,对比研究了SO2缓释杀菌包装、添加1-MCP的SO2缓释杀菌包装等2种保鲜包装方案对葡萄货架期的影响。实验中每2 d分别对包装袋内的顶空气体组成,葡萄的外观质量、水分损失、褐变程度、硬度、糖分、总酸含量和VC含量进行测试分析。结果 SO2缓释杀菌包装能够形成适合葡萄贮藏的自发气调氛围,并且能够抑制葡萄霉菌的滋生。常温保存8d后,裸放组和LDPE组的果梗褐变和烂果严重,而SO2缓释杀菌包装、添加1-MCP的SO2缓释杀菌包装中葡萄褐变程度分别为1级和0级,烂果率分别为3.13%和1.1%。结论 SO2缓释杀菌包装中葡萄的外观和口感均具有商品性,保鲜效果明显。     

核桃仁的酸败及抑制

针对核桃仁在储藏过程容易出现酸败变质的现象,对核桃仁酸败机理及其评价指标进行了分析.并对如何有效的抑制核桃仁酸败提出了一些解决方法,以便于人们对核桃仁的酸败进行控制.