不同包装薄膜对荔枝气调贮藏品质的影响研究

为研究不同包装对荔枝果实气调贮藏品质的影响,在果蔬气调保鲜贮运实验平台上,以"怀枝"荔枝果实作为实验材料,分别采用包装盒、开孔PE袋以及微孔膜袋对其进行包装,开展荔枝果实贮藏实验,以比较不同包装对荔枝果实气调保鲜品质变化的影响。实验结果表明,微孔膜袋包装内外环境差异较小,当外环境温度为3~5℃,相对湿度为85%~95%时,包装内空气温度为5~6℃,相对湿度为88%~90%;经8 d的贮藏,包装盒、开孔PE袋以及微孔膜袋荔枝果实的失重率分别从0增大至1.36%、2.73%、0.74%;包装盒和微孔膜袋比开孔PE袋更能减缓荔枝果实褐变指数和好果率的变化;3种包装对荔枝果实果肉TSS和TA含量的变化影响不显著。研究结果对荔枝果实气调保鲜贮运包装的选择和设计具有一定的参考价值。     

自发气调包装对芥蓝采后叶绿素降解及品质保持的影响

为了探究不同自发气调包装对芥蓝贮藏期间品质与叶绿素降解的影响,分别用市售低密度聚乙烯(LDPE)微孔保鲜袋和2种改性LDPE气调袋包装贮藏采后芥蓝,定期测定包装袋内气体及品质变化相关指标。结果表明:在15℃贮藏期间,对照袋内O₂与CO₂体积分数无明显变化,而气调袋内O₂在贮藏初期迅速下降,CO₂快速积累。2种改性气调袋包装均减缓了叶片黄化、失重速率,维持了叶片较高的叶绿素、维生素C、可溶性蛋白质量比。贮藏3d 时,2种改性LDPE气调袋包装组商品率为100%,叶绿素质量比分别下降了14.67%、4.74%;而对照组商品率仅为51.25%,叶绿素质量比下降了26.47%。通过测定叶绿素降解酶活性及检测相关基因表达分析发现,芥蓝叶片黄化衰老过程中叶绿素含量的变化受到CLH1、PPH、PAO、RCCR、NYC基因表达量的调节,且CLH1主要在芥蓝叶片初始衰老过程叶绿素的降解中起作用。自发气调袋包装可减缓芥蓝的生理代谢变化,抑制叶绿素降解酶基因表达变化,延缓叶片黄化,研究结果旨在为控制芥蓝采后品质劣变及贮藏保鲜提供理论依据。     

包装材料的透气性对枇杷保鲜影响的研究

常温条件下枇杷采用不同透气性的聚乙烯袋包装后贮藏,结果显示高透气性聚乙烯袋包装的枇杷除了失重率和可溶性固形物(TSS)含量与中、低透气性包装袋相比没有明显差别外,对腐烂指数、硬度、可滴定酸(TA)、VC含量及感观等品质指标的保持都有明显优势,说明高透气性袋更有利于常温下贮藏枇杷的保鲜。     

不同气调元件对软枣猕猴桃冷藏期保鲜品质及电子鼻判别的影响

为了研究最适宜冷藏期软枣猕猴桃的箱式自发气调,提高软枣猕猴桃的贮运效果,确保软枣猕猴桃的保鲜品质,研究3种不同气调元件(12、7、6号)对‘长江一号’软枣猕猴桃自发形成的微环境气体含量、保鲜品质及电子鼻判别的影响。结果表明:12号气调元件(CO2:4.3%~5.0%、O2:15.9%~16.4%)处理组在软枣猕猴桃腐烂率、可溶性固形物含量、可滴定酸含量和Vc含量中均比对照组(CK)的效果差,且在延缓硬度下降、抑制呼吸强度和乙烯生成速率指标效果中均低于其余两元件;6号(CO2:3.7%~4.7%、O2:16.2%~17.1%)和7号(CO2:2.6%~3.3%、O2:17.6%~18.3%)气调元件处理组的保鲜效果要优于CK组,且7号气调元件在腐烂率、硬度、糖酸含量、Vc含量、呼吸强度和乙烯生成速率中效果最佳,各指标均与CK组之间存在显著(p0.05)差异。另外,通过电子鼻对软枣猕猴桃处理的主成分分析(PCA)和线性判别分析(LDA)分析中可以得到,贮藏一段时间后,7号元件的风味成分仍与初值风味最相近,且LDA可以明显将CK组与3种不同气调元件(12、7、6号)处理组的风味区别。综上所述,12号气调元件保鲜效果最差,6、7号气调元件均可抑制腐烂率的发生,延缓可滴定酸和Vc含量的下降,延缓果实后熟保证其可溶性固形物含量,抑制果实的呼吸高峰和乙烯生成速率,且7号气调元件最适宜冷藏期软枣猕猴桃的贮藏。     

包装材料与乙烯吸收剂,1-MCP组合处理对延长银白杏贮藏期的影响

探讨了延长银白杏的贮藏期的方法。首先对八成熟的银白杏进行1.0μL/m L 1-甲基环丙烯熏蒸处理,然后用不同保鲜袋(PVC袋,PE袋,PE打孔袋)与乙烯吸收剂组合处理,测定在4℃条件下贮藏期间呼吸强度、理化和感官指标的变化。试验结果表明,在7周的贮藏期中,乙烯吸收剂对银白杏果实的保鲜效果无有益影响。在不加乙烯吸收剂的情况下,与其他两种包装和冷藏对照相比,贮藏两周后PVC袋内O2和CO2含量分别保持在3%和3%~5%,达到最佳的气调贮藏条件,使杏果实的呼吸高峰推迟1周,且呼吸强度明显降低;PVC包装在贮藏期内显著延缓果皮、果肉硬度和可滴定酸的下降;3种包装对VC和可溶性固形物含量均无显著影响。经1-甲基环丙烯熏蒸处理,用PVC包装使银白杏的贮藏期于4℃延长至6周,达到较好的贮藏保鲜效果。     

"真空预冷+气调包装"提高桑叶菜在模拟电商物流条件下的贮藏品质

为探索一种更有效的延长桑叶菜货架期的保鲜技术,本试验以单一气调包装为对照,研究不同真空预冷终温结合气调包装对桑叶菜在模拟电商物流贮藏条件下外观品质、失重率、顶空气体分压、呼吸强度和部分营养成分的影响。结果表明：真空预冷对桑叶菜品质具有双面性。较低的预冷终温（5 ℃）反而加速桑叶菜采后品质劣变、不利于贮藏保鲜;适宜的预冷终温（15 ℃）可显著延缓桑叶菜采后外观品质劣变、抑制呼吸作用,减少营养价值流失。15 ℃真空预冷结合气调包装技术可使桑叶菜在模拟电商物流条件下（非冷链）的保鲜期延长到不少于96 h;处理后桑叶菜的呼吸强度显著低于CK（597.20~308 mg CO2/(kg h) vs 464.66~298 mg CO2/(kg h)）,袋内的气体氛围保持较佳水平（氧气：1.44~3.13 kPa、二氧化碳：7.30~7.56 kPa）;贮藏96 h后,与CK相比,真空预冷+气体包装处理桑叶菜的色差L*值高0.52°,a*值低0.41°,多酚和维生素C保留率分别高了7.89%和7.00%,这表明适宜的真空预冷结合气调包装技术可延缓桑叶菜采后品质下降。研究结果不仅为桑叶菜常温物流保鲜提供一种有效的技术解决方案,而且对丰富目前有关桑叶菜采后保鲜技术理论具有重要意义。     

不同透气性聚乙烯袋包装对冷藏枇杷品质的影响

采后枇杷采用不同透气性的聚乙烯袋包装并置于4℃下贮藏,结果显示,中透气性聚乙烯袋包装的枇杷除了失重率和TSS含量没有明显差别外,对腐烂指数、硬度、可滴定酸(TA)、Vc含量及感官等品质指标的保持均明显优于其它两种透气性包装袋,说明中透气性袋更有利于枇杷的保鲜。     

硅窗袋保鲜芹菜的研究

研究了不同温度以及硅窗袋内不同初始气体浓度比例对芹菜贮藏效果的影响,测定了芹菜贮藏过程中失重率、黄化率、腐烂率、呼吸强度、袋内O2、CO2含量、细胞膜透性、粗纤维含量等指标的变化,结果表明:温度对芹菜贮藏效果影响显著,但15℃与5℃环境下芹菜贮藏效果相差不大。硅窗袋充气气调包装可以延缓采后芹菜的衰老,延长芹菜的货架寿命,15℃环境下芹菜贮藏15d后仍具有较好的商品价值。其中初始气体比例为5%CO2/5%O2/90%N2的包装袋芹菜贮藏结束后品质最佳。     

不同包装材料对羊肚菌保鲜效果的影响

以人工种植羊肚菌为试材,采用3种包装(微孔膜、PE膜和透湿袋)在1℃下进行贮藏,定期测定其生理指标及感官品质,筛选最适于羊肚菌保鲜的包装材料。结果表明,与PE膜和透湿袋处理相比,微孔膜包装在贮藏期间可以更有效地减少羊肚菌质量损失,降低呼吸强度,减轻褐变程度,使可溶性固形物含量和多酚含量维持在较高水平,降低多酚氧化酶活性,保持较高的过氧化物酶活性。冷藏35 d,微孔膜包装的羊肚菌感官评分高于空白对照和其他包装材料处理组。微孔膜包装结合1℃冷藏处理是羊肚菌最佳保鲜方式,可以有效维持羊肚菌品质,延长贮藏期,在羊肚菌采后保鲜上具有较好的应用前景。     

气调熏蒸微孔包装技术在葡萄采后贮运中的应用

为解决新疆鲜食葡萄电商物流“个性化”对保鲜包装技术的需求。分析气调包装（5% O2+8% CO2）结合不同浓度二氧化硫（sulfur dioxide,SO2）（100、300、500、800 μL/L）熏蒸对新疆红地球葡萄采后生理指标的影响,研究气调熏蒸包装保鲜技术对红提葡萄采后品质的影响。结果表明：与对照相比,气调熏蒸微孔包装能够较好的保持果实硬度、可溶性固形物含量（TSS）、可滴定酸含量（TA）和维生素C含量（Vc）,减缓pH上升趋势,维持果实采后品质。500 μL/L SO2+5% O2+8% CO2处理保鲜效果较好,贮藏8 d后,pH值为4.26,低于对照组;葡萄果实硬度为10.76 N,TSS含量为16.67%,TA含量为0.52%,Vc含量为1.18 mg/100 g,均高于对照组,表明气调熏蒸微孔包装方式能够有效延长葡萄感官品质和商品性,减缓红地球葡萄营养风味的损失。因此,500 μL/L SO2+5% O2+8% CO2气调熏蒸微孔包装技术可为鲜食葡萄采后贮运保鲜技术研究提供理论和数据支持。     

EFFECT OF INTERMITTENT WARMING AND MODIFIED ATMOSPHERE PACKAGING ON COLOR DEVELOPMENT OF PEACHES

Peaches (Prunus persica L. Batsch cv. ‘Paraguayo’) at firm-breaker stage of maturity were stored at 0.5 C for 3 weeks. Intermittent warming (IW) for 1 day at 20C every 6 days of cold storage at 0.5C, modified atmosphere packaging (MAP) generated by 42 μm oriented polypropylene bags, and a combination of MAP and IW were applied. Changes in skin and flesh color (measured by CIELAB parameters and Chroma and Hue angle color indices) during normal postharvest ripening at 20C, during cold storage and after 3 days of post-storage ripening were studied. For commercial purposes, IW led to the same color level being reached as was found in normal postharvest ripened fruits. In contrast, the high carbon dioxide and low oxygen generated by MAP alone or combined with IW delayed color development even during post-storage ripening. Ground color measured by hue angle was the best index for monitoring color evolution during ripening and storage.     

Use of modified atmospheres to prolong the postharvest life of Burlat cherries at two different degrees of ripeness

The effects of degree of ripeness and packaging atmosphere on the quality of the very early season cherry (Prunus avium) cultivar ‘Burlat’ have been studied. Cherries were classified into two groups depending on their stage of ripening, taking colour as a maturity index (red and purple). After rapid chilling, cherries were sealed in 50 µm low‐density polyethylene (LDPE) bags in four different atmosphere compositions. Packages were stored at 2 °C and cherries were analysed weekly until they were deemed to be commercially unacceptable (after 4 weeks for red cherries and 3 weeks for purple cherries). Changes in atmosphere composition, skin colour, pigment content, titratable acidity, soluble solids, firmness and sensory quality were monitored. Acceptability was higher for the less mature group of cherries. Colour shifted in both groups, initially from red to blue/red and later on back to red. Titratable acidity decreased at the end of the experimental period for all samples. Firmness increased at first, but towards the end of the experiment it was similar to the initial value. The gas composition of the four modified atmosphere conditions approached a final equilibrium consisting of 9–12% CO₂ and 1–3% O₂. For long‐distance transportation of Burlat cherries the following procedure is recommended: harvest at the red colour stage, package in air using LDPE bags and maintain the temperature at 2 °C. Under these conditions, red Burlat cherries can be kept in an excellent commercial state for 3 weeks. © 2000 Society of Chemical Industry     

不同包装对甜椒贮后货架期挥发性物质及理化品质的影响

以甜椒鲜果为原料,运用电子鼻结合顶空固相微萃取-气相色谱质谱（head space solid-phase microextractionand gas chromatography mass spectrometry,HS-SPME-GC-MS）联用技术,对甜椒10 ℃冷藏15 d后进行常温贮后货架期间挥发性成分进行测定,探究不同包装（无包装对照、微孔袋、20 μm聚乙烯袋包装）对其挥发性物质的影响,通过测定果实质量损失率、VC含量、糖酸比等指标分析不同包装对甜椒理化品质的影响。结果表明,电子鼻能够区分不同包装方式、不同贮后货架期的甜椒整体挥发性物质;GC-MS分析得出,甜椒的挥发性成分主要为酯类和醇类物质,且随着贮后货架时间的延长,酯类物质不断减少,而醇类物质则不断上升,对照、微孔袋、20 μm聚乙烯袋3 组酯类相对含量分别下降了47.33%、23.43%和51.39%,醇类相对含量分别上升了68.73%、56.80%和72.96%,说明微孔袋包装可以有效延缓酯类物质的损失以及延缓醇类物质的增加,有效改善甜椒常温货架期间的香气成分,其保鲜作用优于对照和20 μm聚乙烯袋组;相同贮后货架期下微孔袋组的VC含量和糖酸比均最高,微孔袋、20 μm聚乙烯袋包装组之间质量损失率差异不显著（P＞0.05）,但明显小于对照组（P＜0.05）,说明微孔袋包装对甜椒贮后货架期理化品质的保鲜作用优于对照和20 μm聚乙烯袋组。     

Modified Atmosphere Packaging of Cultivated Mushroom (Agaricus bisporus L.) with Hydrophilic Films

ABSTRACT: Unique gas barrier properties of hydrophilic films (wheat gluten-based material and synthetic polymer) have been tested through practical application such as modified atmosphere packaging. Mushrooms have been packed under microporous and hydrophilic films and stored at 10 °C and 20 °C under high relative humidity (> 92%). Atmospheric and quality changes (cap opening, color) were assessed during storage. Unique steady state atmospheres, poor in both oxygen and carbon dioxide, were observed, regardless of the temperature and the hydrophilic film used, owing to their high selectivity to gas diffusion. A transitional phase characterized by a CO₂ partial pressure peak has been evidenced and could imply quality change. The proposed MAP model fit experimental data with a mean error of 0.88 kPa.     

不同气调包装对核桃仁贮藏品质的影响

将生核桃仁原料分别采用低O2高CO2的聚乙烯(PE)及复合材料(KNY17//CPE80)材料包装密封后,置于(2±1)℃冷库贮藏;以普通聚乙烯(PE)包装为对照,通过定期检测相关品质指标,研究不同气调方法对核桃仁的影响。结果表明：纳米包装和低O2高CO2的PE包装保鲜效果最好,两者均能显著抑制核桃仁过氧化值、酸价升高,保持良好外观品质,而且两种方法贮藏的生核桃仁加工成琥珀核桃仁后,经高温加速贮藏试验,过氧化值、酸价、羰基价都显著低于对照组。     

1-MCP结合微孔、打孔保鲜袋对‘富士’苹果贮藏品质的影响

为了解‘富士’苹果在冷藏条件下适合的保鲜处理方式,探究了在(0±1) ℃贮藏条件下,微孔、打孔保鲜袋结合小包装便携1-MCP处理(处理剂量为0.875 μL/L)对‘富士’苹果果实硬度、外观色泽、TSS含量、TA含量、MDA含量、POD活性和PPO活性变化的影响。试验共设5个处理:纸箱衬微孔膜包装、纸箱衬微孔膜包装+1-MCP、纸箱衬打孔膜包装、纸箱衬打孔膜包装+1-MCP处理、纸箱装未加任何包装的裸果为对照(CK)。结果表明:1-MCP结合保鲜袋处理能有效延缓富士苹果果实硬度、TSS、TA的下降速度,抑制a*值降低和b*值升高,降低贮藏后期MDA的生成量,保持POD活性,并使之保持在较高水平,有效抑制PPO活性,延迟PPO活性高峰。其中以微孔+1-MCP处理效果最佳,贮藏225 d时,微孔保鲜袋结合1-MCP处理TA含量为0.12%,硬度为5.78 kg/cm2,MDA含量最低,POD活性最高,PPO活性最低,分别为9.63 mmol/g、15.47 U/(min·g)和8.82 U/(min·g),且这些指标与对照均差异显著(P<0.05)。因此,建议生产中采用微孔保鲜袋和小包装1-MCP处理剂的内包装。     

基于主成分分析法研究自发气调包装对方竹鲜笋保鲜效果的影响

采用不同自发气调袋结合低温处理对方竹鲜笋进行贮藏保鲜,探究方竹鲜笋的最佳保鲜工艺。将方竹鲜笋采用四种不同的自发气调袋（WK、PE20、PE30、PE40）在(1.0±0.3)℃的保鲜库贮藏50 d,每隔10 d取样对方竹鲜笋贮藏期间的呼吸强度、硬度、褐变指数、多酚、可溶性蛋白质、苯丙氨酸解氨酶（PAL）、过氧化物酶（POD）等指标进行测定,结合主成分分析法分析不同自发气调袋对方竹鲜笋的保鲜效果。结果表明:PE20袋可以有效降低方竹鲜笋呼吸强度,抑制硬度的上升,延缓方竹鲜笋总色差值的改变,抑制方竹鲜笋贮藏期间腐烂率、褐变指数、POD活性和PAL活性的上升,使方竹鲜笋的营养物质（V_C、可溶性蛋白质）维持在较高水平。主成分分析表明,呼吸强度、硬度中、腐烂率等是影响方竹鲜笋保鲜的关键指标,将分析结果进行综合评价得分,50 d时PE20包装的综合评价得分高于其他三种自发气调包装。综合指标测定和主成分分析结果表明PE20袋处理对方竹鲜笋的保鲜效果最佳。     

QUALITY OF MODIFIED ATMOSPHERE PACKAGED "BARTLETT" PEARS AS INFLUENCED BY TIME AND TYPE OF STORAGE

Commercially mature “Bartlett” pears for this study were obtained from local commercial packing facilities. In the first year, pears were packed in modified atmosphere bags and placed in boxes or packed normally (control) with an individual paper wrap around each pear plus a polyethylene liner in the box. Boxed pears from both types of packaging were stored in regular atmosphere (RA) storage at 1C for 30 or 90 days. In the second year, pears were packed normally and stored in both RA or controlled atmosphere (CA) storage for 45 or 90 days, or packed in modified atmosphere bags and stored in RA at 1C. After 45 days, normally packed pears from both RA and CA were removed from their initial storage, placed in modified atmosphere bags and returned to RA storage for an additional 45 days. Pears stored in modified atmosphere bags were superior in quality to normally packed pears stored only in RA storage and equal in quality to pears stored in CA for periods of 90 days. The quality of pears held in modified atmosphere bags under CA conditions deteriorated after only short periods of time (<45 days). Pears in modified atmosphere bags should be stored only in RA. Little or no quality advantage was evident if use of modified atmosphere bags was delayed regardless of prior storage type.     

Storage of green coffee in hermetic packaging injected with CO2

The objective of this study was to evaluate the physical, chemical, and sensory qualities of green coffee beans (Coffea arabica L.) during storage in different types of packaging. Coffee was stored from October 2008 to September 2009 in a warehouse of the Agriculture Society Ltda. (SAAG) in Santana da Vargem, southern Minas Gerais State, Brazil. The treatments in the factorial design consisted of two types of packaging (hermetic big bags with the injection of up to 60% CO₂ in a controlled atmosphere; similar bags but without the injection of CO₂ in a modified atmosphere) and three sampling positions in the bags (high, medium, and low). At 3-month intervals during a 12-month period, grains were analyzed to determine their water content, color, electrical conductivity, potassium lixiviation, and content of sugars. Sensory analysis was also conducted at these sampling times. The storage of green coffee beans in hermetic big bags on a commercial scale under modified and controlled atmospheric conditions is viable over a 12-month period. The coffee packed in big bags maintained its quality and exhibited an intensification of the green coloration of the grains during storage. Sensory analysis of coffee beans stored in a controlled atmosphere showed that the medium sampling position yielded the best ratings. The results of this analysis demonstrated that this storage technique can potentially increase the effectiveness of methods used to preserve the sensory quality of coffee beans.