石榴采后病害及贮藏保鲜技术研究进展

石榴果实色泽鲜艳、籽粒营养丰富、鲜食味美可口,深受消费者喜爱,但石榴采后易发生果皮褐变和腐烂变质而严重影响其商品价值。本文对石榴采后病害、贮藏环境因素和相关保鲜技术进行综述,着重介绍石榴贮期生理病害和微生物病害的起因、症状及防控措施,在确定贮藏温度、相对湿度、气体成分、环境净度为影响贮藏品质的相关因素的基础上,详细叙述了机械冷藏、自发气调包装贮藏、气调贮藏、涂膜贮藏等保鲜方法,并对未来贮藏保鲜技术的发展方向进行展望,旨在为石榴贮藏保鲜提供理论参考。     

贮藏温度对鲜食石榴籽粒贮藏品质及抗氧化能力的影响

研究不同贮藏温度(0、5、10℃和室温)对鲜食石榴籽粒贮藏品质、活性成分及抗氧化能力的影响。结果表明,与10℃和室温贮藏条件相比,0℃和5℃能减缓石榴籽粒的呼吸速率、抑制相对电导率和质量损失率的升高、提高抗氧化活性,大大延长了商品货架期。其中,0℃更好地保持了可溶性固形物含量和花色苷稳定性,并能保持更好的品质和货架期,因此,0℃可作为鲜食石榴籽粒最适宜的贮藏温度。     

石榴复合贮藏保鲜技术研究

以陕西临潼净皮甜石榴为试材,通过正交实验确定石榴复合贮藏保鲜技术的最优方法为:石榴预冷后采用pH4.0的0.5%CMC(羧甲基纤维素钠)溶液涂膜,在温度5.0℃和气体成分CO2=5%、O2=8%的条件下贮藏,贮期每隔10d换气1次,每隔5d在15℃下升温处理24h,再置于5.0℃下贮藏,如此循环处理,石榴可贮藏120d,籽粒总糖含量13.6%,果皮褐变指数0.15,腐烂率2.2%,果实外观色泽鲜艳,籽粒感官品质良好,保鲜效果理想。     

鲜食无花果贮藏保鲜技术研究进展

无花果营养丰富,在中国的栽培不断扩大,具有广阔的市场潜力,但无花果鲜果的贮藏保鲜是影响无花果产业发展的重要限制因素。本文概述了鲜食无花果的贮藏特性及影响因素,同时分别对鲜食无花果目前采用的物理保鲜、化学保鲜、生物保鲜、复合保鲜技术以及其他新的保鲜技术研究进行了总结,以期为无花果的高效贮藏保鲜提供参考。     

鲜食玉米常温保鲜工艺研究

以不同质量浓度的白砂糖、食盐、食醋为原料配制保鲜液,对鲜食玉米进行常温保鲜研究。通过单因素实验分别确定白砂糖、食盐、食醋的最佳浓度,利用正交实验确定复合保鲜液的最佳浓度配比,并对鲜食玉米进行保鲜。分析贮藏过程中,感官品质、失重率、弹性及气味的变化。结果表明,复合保鲜液质量浓度配比为白砂糖3 g/L、食盐10 g/L、食醋5 g/L时,贮藏30 d,鲜食玉米气味变化较小,籽粒饱满度较好,保鲜效果显著。     

鲜食葡萄贮藏保鲜技术研究进展

葡萄在贮藏保鲜过程中极易収生腐烂、落粒、失水、褐变等现象,严重制约着鲜食葡萄产业的収展。近年来,各国对葡萄的贮藏保鲜都迚行了大量试验研究,技术的更新和方法的联用使得鲜食葡萄得以更好的贮藏保鲜。本文对国内外兲于鲜食葡萄贮藏保鲜的传统方法、物理方法、化学方法、生物方法及其他一些技术做了较全面的总结和综述,以期为鲜食葡萄的贮藏保鲜提供理论参耂。     

不同pH值CMC涂膜对石榴果实采后生理指标及贮藏品质的影响

以陕西临潼净皮甜石榴为试材,研究了不同pH值CMC涂膜对石榴果实采后生理指标及贮藏品质的影响。结果表明:石榴在(4.0±0.5)℃条件下贮藏,采用pH值5.0、0.5%CMC溶液涂膜,能有效保持石榴籽粒可溶性固形物含量、总糖含量和可滴定酸含量,减缓果皮相对电导率和褐变指数升高速率,降低果实呼吸速率和腐烂率,抑制果皮抗坏血酸氧化酶(AAO)和多酚氧化酶(PPO)活性,保持果皮过氧化物酶(POD)活性相对较高水平。贮藏120d果实外观色泽鲜艳,籽粒感官品质良好,保鲜效果理想。     

三种涂膜保鲜剂对石榴果实贮期品质的影响

以陕西临潼净皮甜石榴为试材,研究了壳聚糖、海藻酸钠和明胶三种涂膜保鲜剂对石榴果实贮藏期间品质变化的影响.结果表明:在温度为5.0±0.5℃条件下贮藏,采用1%壳聚糖溶液涂膜,能有效保持石榴果粒可溶性固形物含量和可滴定酸含量,减缓果皮相对电导率和褐变指数升高速率,贮藏120d果实外观色泽鲜艳,籽粒感官品质良好,保鲜效果理想;而采用1%明胶和1%海藻酸钠溶液涂膜处理的石榴贮期果粒可溶性固形物含量和可滴定酸含量下降严重,果皮相对电导率和褐变指数上升较快,籽粒风味劣化,感官品质不佳.     

石榴贮藏期间间歇升温处理对果实品质的影响

以陕西临潼净皮甜石榴为试材,研究了间歇升温处理对石榴果实贮藏期间品质变化的影响。结果表明:石榴在(5.0±0.5)℃条件下贮藏,每隔6 d在(15±0.5)℃下间歇升温处理24 h,能有效保持果粒可溶性固形物含量、总糖含量和可滴定酸含量,减缓果皮褐变指数升高速率,降低果实腐烂率,贮藏120 d果实外观色泽鲜艳.籽粒感官品质良好,保鲜效果理想。     

复合生物保鲜剂对鲜食玉米贮藏品质的影响

采用壳聚糖、花粉多糖、茶多酚为主配制的复合生物保鲜剂对鲜食玉米进行保鲜,测定含水量、质量损失率、硬度、气味与感官品质,研究贮藏期间鲜食玉米的品质变化。结果表明,与对照相比,冷藏条件下经保鲜剂处理的鲜食玉米贮藏30 d时含水量减少损失18.6%,质量损失率降低19.9%,硬度降低42.68 N,气味变化较小,感官品质良好。生物保鲜剂可有效抑制鲜食玉米水分散失,减少营养成分损失,降低质量损失率,保持籽粒弹性;还可保持鲜食玉米的色泽、形态、气味、滋味等感官品质,因此,生物保鲜剂对鲜食玉米的保鲜效果显著。     

高压静电场结合自发气调对低温冷藏下蒙自石榴的保鲜效果研究

针对贮藏过程中蒙自石榴皮薄、易失水及褐变问题,研究高压静电场结合自发气调技术对新鲜石榴保鲜效果的影响。以蒙自"绿籽"石榴为试材,在商用冷库条件下,测定呼吸强度、可溶性固形物、总酚含量、果皮水分含量等指标。结果表明:塑料大帐进行自发气调可以维持一个相对较高CO2体积分数(5.17%~7.17%)和低O2体积分数(14.05%~15.87%)的微环境。与对照组相比,高压静电场和自发气调技术均可降低石榴的呼吸强度、减少营养物质消耗、维持较高的果皮水分含量、延缓果皮皱缩发褐现象。冷藏至85 d后,高压静电场结合自发气调处理的石榴表面褐变程度及营养价值均保持最好(P<0.05)。因此,高压静电场结合自发气调处理石榴可以有效减缓果实衰老进程,维持较好的品相,延长石榴保鲜期。     

河阴石榴的采后保鲜技术

研究贮藏温度、化学杀菌剂处理和涂膜对河阴石榴果皮褐变、质量损失率、腐烂及籽粒品质等指标的影响。结果表明,在120 d的贮藏期内,4.5 ℃会引起河阴石榴果实冷害,果皮褐变严重、腐烂率增大。1%壳聚糖涂膜处理降低果实的腐烂率、褐变指数和质量损失率的效果优于1%海藻酸钠和1%羧甲基纤维素钠涂膜。噻菌灵、甲基托布津和多菌灵1 000 倍稀释液浸果60 s可以显著降低果实腐烂率,3 种化学杀菌剂处理之间无显著差异。以42%噻菌灵悬浮剂1 000 倍液浸果,而后以1%壳聚糖溶液涂膜,用0.015 mm聚乙烯保鲜袋单果包装后放入6 ℃条件下贮藏120 d,河阴石榴的腐烂率为3.46%,质量损失率为2.13%,褐变指数为0.11,可溶性固形物含量为14.5%,籽粒品质评分为92,具有较高的商品价值。     

Postharvest biology and technology of pomegranate

Pomegranate is a subtropical and tropical fruit of great importance from a health point of view. Despite increasing consumer awareness of the health benefits of pomegranate, consumption of the fruit is still limited owing to poor postharvest handling, storage recommendations, short shelf life and quality deterioration during transportation, storage and marketing. The occurrence of physiological disorders such as husk scald, splitting and chilling injury is another challenge reducing marketability and consumer acceptance. Recently, notable work on postharvest biology and technology has been done. Pomegranate is highly sensitive to low‐oxygen (<5 kPa) atmospheres, chilling injury and decay. One of the major problems associated with pomegranate fruit is excessive weight loss, which may result in hardening of the husk and browning of the rind and arils. To reduce chilling injury incidence and to extend storability and marketing of pomegranates, good results were obtained with polyamine, heat, salicylic acid, methyl jasmonate or methyl salicylate treatments prior to cold storage. This article reviews the maturity indices, changes during maturation and ripening, postharvest physiology and technology of pomegranate fruit as well as the various postharvest treatments for maintaining fruit quality. © 2015 Society of Chemical Industry     

低温结合1-MCP处理对突尼斯软籽石榴采后品质的影响

突尼斯软籽石榴在贮藏过程中容易出现果皮褐变、籽粒变质、软化腐烂等问题,严重影响果实的商品价值。以陕西潼关突尼斯软籽石榴为试材,研究低温结合1-甲基环丙烯(1-methyl-cyclopropene,1-MCP)处理对采后突尼斯软籽石榴品质的影响,即在贮藏温度(3±0.5)℃、相对湿度90%~95%条件下,选用0.2、0.5、1.0、1.5 mg/L四种不同质量浓度的1-MCP处理软籽石榴,贮藏期间每20 d测定石榴果实的可滴定酸、可溶性固形物、还原糖含量,呼吸强度、相对电导率、褐变指数及多酚氧化酶、过氧化物酶活性,并计算果实失重率和腐烂率,贮藏120 d时对软籽石榴的感官性状进行综合评价。结果表明,采用1.0 mg/L的1-MCP处理软籽石榴能有效减缓果实腐烂变质,减缓果实呼吸强度,降低褐变指数,较好地保持籽粒可溶性固形物、可滴定酸及还原糖含量,并使多酚氧化酶、过氧化物酶活性处于较低水平,降低果实失重率和腐烂率,保持良好的感官品质。突尼斯软籽石榴适宜的贮藏条件为:贮藏温度(3±0.5)℃、相对湿度90%~95%、1-MCP处理质量浓度1.0 mg/L,并用聚乙烯塑料袋密封包装,保鲜效果理想。     

茶树油复合多种天然产物对樱桃的保鲜作用研究

以樱桃为保鲜研究对象,从抑制腐败微生物、调控呼吸及提高抗氧化能力的保鲜机理出发,采用茶树油、壳聚糖、石榴皮提取物和桑叶提取物进行复配,研制水果天然保鲜剂。结果表明:保鲜溶液的最优配比为壳聚糖、桑叶提取物和石榴皮提取物质量比为12:3:5、茶树油含量为1 mg/L。该保鲜剂不仅能降低樱桃水分损失和烂果率,还能维持果实体内较高的V_C和可滴酸含量,延长货架时间约5 d。以上研究表明,基于保鲜机理研制的茶树油复合天然保鲜剂,可有效保持樱桃营养价值和风味,具有替代樱桃常规保鲜的潜在价值。     

采后果实减压贮藏技术的研究进展

减压贮藏技术作为果蔬贮藏保鲜史上的第三次技术革命,可有效提高采后果实的贮藏品质,尤其是对易腐园艺水果产品。该文结合当前减压贮藏技术的研究进展,介绍了减压贮藏的基本原理和方式、减压对采后果实的贮藏保鲜效果,并针对减压贮藏研究和应用过程中的问题提出了未来的研究方向。     

Selected Mechanical Properties of Pomegranate Peel and Fruit

Mechanical property data of pomegranate fruits are limited. The objective of this study was to determine the compression and cutting properties of whole fruit as well as the puncture strength of peel samples of fruit at different storage times. The results showed that storage time had a significant effect on all the properties studied in this work except for peel shear strain (p < 0.05). The whole fruit cutting energy and power, maximum cutting force, peel shear strength and strain and shear modulus showed an increasing trend with storage time. However, firmness, bioyield force, and modulus of elasticity increased and then decreased with storage time.     

The flavor of pomegranate fruit: a review

Despite the increasing commercial importance of pomegranate, especially because of its recently discovered health‐promoting benefits, relatively little is yet known regarding its sensory quality and flavor preferences, or about the biochemical constituents that determine its sensory characteristics. The perceived flavor of pomegranate fruit results from the combination of various taste, aroma and mouthfeel sensations. The taste is governed mainly by the presence of sugars (glucose and fructose) and organic acids (primarily citric and malic acids). The aroma evolves from the presence of dozens of volatiles, including alcohols, aldehydes, ketones, and terpenes, which provide a mixture of various ‘green’, ‘woody’, ‘earthy’, ‘fruity’, ‘floral’, ‘sweet’ and ‘musty’ notes. In addition, the sensory satisfaction during the eating of pomegranate arils is complemented by various mouthfeel sensations, including seed hardness and astringency sensations. In the present review we will describe the sensory quality and flavor preferences of pomegranate fruit, including the genetic diversity in flavor characteristics among distinct varieties. In addition, we will describe the dynamic changes that occur in fruit flavor during fruit ripening and postharvest storage. © 2013 Society of Chemical Industry