MAP对轻度加工茭白品质的影响及其模型建立

研究了气调色装(MAP)对轻度加工茭白品质的影响。结果表明:高密度聚乙烯为材料的MAP可保持轻度加工茭白的嫩度,并建立了数学模型,通过模型可预测包装袋内氧和二氧化碳的浓度。     

常温下初始气体比例气调包装对茭为品质的影响

研究了短期内常温下不同初始气体比例气调包装(MAP)对轻度加工茭白品质的影响。研究结果表明:不同初始气体浓度MAP对轻度加工茭白硬度、VC含量、纤维素含量、叶绿素含量、感官评价值等影响显著,当初始气体比例为CO2/O2/N2:5%/3%/92%时,可以较好地保持茭白的营养及食用品质,贮藏3d后,茭白的硬度从6.161N增加至7.248N,VC的相对保留率从100%降低至54.18%,纤维素含量从4.10%增加至15.30%,叶绿素含量为12.07μg/g增加至60.39μg/g,感官评分从9.0降低至7.0。     

采后1-MCP和乙烯利处理对茭白呼吸代谢及细胞结构的影响

为探索茭白采后衰老的调控机制,研究了采后10μL/L 1-甲基环丙烯(1-MCP)和1.25 mg/L乙烯利(ET)处理对茭白常温(25℃)贮藏期间呼吸代谢和细胞超微结构的影响。结果显示,1-MCP处理显著抑制了茭白贮藏期间色差L、a*值、b*值和失重率的上升;呼吸强度和还原糖含量显著低于对照;超氧化物歧化酶(SOD)活性在贮藏第1 d高于对照,其余贮藏时间低于对照,琥珀酸脱氢酶(SDH)和过氧化物酶(POD)活性在整个贮藏期间低于对照而细胞色素c氧化酶(CCO)活性高于对照,维持较低的相对电导率和丙二醛(MDA)含量;贮藏6 d后细胞壁完整、线粒体清晰。乙烯利处理对呼吸和活性氧相关代谢与1-MCP处理有相反效果。以上结果表明,采后1-MCP处理可显著抑制茭白采后呼吸代谢和活性氧产生,从而有效保持能量代谢平衡和细胞结构的完整性,延缓茭白组织的衰老和品质劣变。     

1-MCP 结合PE 包装处理对带壳茭白贮藏品质的影响

为探究低温贮藏条件下1-甲基环丙烯（1-methylcyclopropene,1-MCP）结合聚乙烯（polyethylene,PE）保鲜袋包装处理对带壳茭白采后贮藏品质和木质化进程的影响,以新鲜带壳茭白为原料,将其分别用0.07 mm PE 袋、0.14 mm PE 袋、0.07 mm 纳米复合PE 袋、1-MCP 结合0.07 mm PE 袋、1-MCP 结合0.14 mm PE 袋包装。各处理组于（1±1）℃条件下贮藏,定期检测分析各组原料的理化指标。结果表明：1-MCP 结合不同厚度的PE 袋处理均能有效减缓茭白硬度和L* 值的降低,维持果实中总糖和还原糖的含量,并且通过抑制丙二醛含量的升高和过氧化物酶活性的增加,减缓茭白中纤维素和木质素的合成和积累。其中1-MCP 结合0.14 mm PE 袋对带壳茭白的保鲜效果最好,能够有效延缓茭白的采后衰老,延长贮藏期并改善其贮藏品质。     

MA贮藏对采后茭白糠心和品质的影响

为了探讨MA贮藏对茭白保鲜的效果,研究(1±1)℃下MA贮藏对采后茭白品质和生理的影响.结果表明:采后茭白叶绿素酶活性增加1.4倍,使叶绿素含量下降43%;苯丙氨酸解氨酶(PAL)和过氧化物酶(POD)活性增加,导致茭肉纤维素和木质素含量分别增加32%和36%.MA贮藏不仅可显著降低茭白的呼吸强度和乙烯释放量,还可延缓叶绿素酶、PAL和POD活性的增加,茭白的总糖含量和叶绿素含量分别比对照高21%和34%,而空心指教、纤维素和木质素含量分别为对照的66%、92%和81%.表明MA贮藏可抑制茭白的黄化和糠心进程.     

MAP包装对微加工茭白品质的影响

研究了MAP包装对茭白的嫩度、表皮色泽、叶绿素含量及细胞质膜相对透性的影响。结果表明:高密度聚乙烯包装可保持茭白的嫩度、抑制果皮中叶绿素的合成及细胞质膜透性的增加。     

低温下不同包装方式对生菜贮藏品质影响的研究

本文研究了低温条件下不同包装方式对生菜贮藏品质的影响。挑选新鲜的、无病斑、无机械损伤、成熟度、大小一致的散叶生菜为试验材料,分别装入PE保鲜袋以及自发气调保鲜袋(MAP)内,以无包装组作为对照,贮藏在(0±0.2)℃的冷库中。在贮藏过程中,通过定期抽样检测其失重率、可溶性固形物含量、VC含量、叶绿素含量、丙二醛(MDA)含量、多酚氧化酶(PPO)活性以及乙烯释放速率,比较不同的包装方式对生菜贮藏保鲜效果的影响。结果表明:在(0±0.2)℃贮藏条件下,MAP和PE保鲜袋均可有效延缓生菜的营养物质的损失,减缓失重率和丙二醛含量的上升,降低生菜PPO活性及乙烯释放量的增加。贮藏至第18天,PE包装组与MAP包装组失重率比对照组分别降低了0.65%和0.75%。而MAP比PE保鲜袋能更好地保持生菜的贮藏品质及营养品质。     

基于iTRAQ技术研究采后1-甲基环丙烯和乙烯利处理对茭白线粒体蛋白质组变化的影响

为探讨茭白采后衰老的分子机制,应用同位素标记相对与绝对定量蛋白质组学技术研究了茭白常温贮藏期间线粒体蛋白质表达谱的变化及1-甲基环丙烯（1-methyleyelopropene,1-MCP）和乙烯利（ethylene,ET）处理对茭白线粒体蛋白质组变化的影响。结果表明：共鉴定到肽段数大于等于2的可信蛋白1 908 个,与贮藏0 d相比,对照（CK）组、ET和1-MCP处理组茭白贮藏3 d和6 d后,共有315 个蛋白表达量变化倍数在2.0 倍以上且重复组数据统计学差异显著（P＜0.05）。生物信息学分析显示代谢途径、次生代谢产物生物合成、氨基酸生物合成与代谢、核苷酸代谢、含碱基小分子代谢途径等可能与茭白采后衰老有关,三羧酸循环、氧化磷酸化、磷酸戊糖途径、C5支链二元酸代谢及氨基酸代谢途径可能在茭白采后衰老中发挥重要作用。这些差异表达蛋白的生物学功能分析表明,茭白采后碳水化合物水解加速,磷酸戊糖途径加强而糖酵解途径和氧化磷酸化减弱,导致能量合成减少,同时形成氧化胁迫,这可能激活Ca2＋/MAPKs、细胞色素c和茉莉酸等信号途径,造成初级代谢紊乱和次级代谢产物（如木质素）积累,从而促进细胞凋亡或细胞坏死,最终加速衰老。     

纳米壳聚糖涂膜对鲜切茭白品质的影响

研究了纳米壳聚糖涂膜对鲜切茭白品质的影响。鲜切茭白分别在去离子水（对照）、10 g/L壳聚糖或10 g/L壳聚糖+1.5 g/L纳米壳聚糖溶液中浸泡3 min,自然晾干包装后于1±0.5 ℃下贮藏12 d。贮藏过程中每3 d测定鲜切茭白的白色指数(WI)、硬度、失重率及木质素、还原糖、抗坏血酸含量,PAL、SOD、CAT和POD活力。结果显示,纳米壳聚糖涂膜显著抑制了鲜切茭白WI值的下降和木质素含量的增加,维持了相对高的硬度及还原糖和抗坏血酸含量;贮藏12 d后失重率为1.12%;PAL和POD活性显著低于对照（P<0.05）,SOD和CAT活性显著高于对照（P<0.05）。以上结果表明,纳米壳聚糖涂膜能有效延缓鲜切茭白褐变和木质化,提高抗氧化酶类活性,提示纳米壳聚糖涂膜具有商业上控制鲜切茭白品质劣变的潜在价值。     

微环境气调保鲜箱对葡萄采后贮藏品质的影响

以‘阳光玫瑰’葡萄为试验材料，分别采用配备不同气调元件的保鲜箱(MAP1、MAP2、MAP3)进行包装，以无气调元件保鲜箱为对照(CK)，于冰温((–0.5±0.3)℃)条件下贮藏，研究不同气调元件保鲜箱对葡萄果实感官指标、营养指标、生理指标及相关酶活性的影响。结果表明，在冰温贮藏过程中，MAP1、MAP2、MAP3处理组O₂含量变化范围分别为：18.7%～19.7%、18.7%～19.5%和18.4%～19.0%;CO₂含量变化范围分别为：0.2%～0.8%、0.6%～1.4%和0.9%～2.3%。与CK相比，3种气调元件均可在不同程度上降低保鲜箱内O₂含量、提高CO₂含量，进而抑制葡萄果实的生理活动，延缓果实贮藏品质的下降。其中MAP3处理组可有效降低贮藏期间葡萄果实的腐烂率、落粒率和失重率，较好地维持葡萄果皮亮度和果肉硬度，延缓营养物质(Vc、可滴定酸和可溶性固形物)的流失，在一定程度上抑制葡萄果实的呼吸速率及乙烯生成速率，延缓丙二醛(MDA)含量和相对电导率的上升，较好地保持果实超氧化物歧化...     

响应面法优化笋头多糖微波-超声波辅助提取工艺

本文以福建毛竹笋笋头为原材料,在单因素实验的基础上,结合响应面分析法对微波-超声波联合辅助传统水提笋头多糖的工艺参数进行优化。结果表明,微波-超声波联合辅助传统水提笋头多糖的最优工艺参数为料液比1:30 g/mL、水浴温度95℃、水浴时间2.0 h、超声波功率600 W、微波功率300 W、微波-超声波时间3.0 min。在此条件下笋头多糖得率为10.05%,对比传统热水浸提法笋头多糖得率提高了32.06%。经检测,笋头多糖的总糖、蛋白质和糖醛酸含量分别为74.87%、4.05%和1.89%。该方法能显著提高笋头多糖得率,可为竹笋的综合利用和笋多糖产品的进一步开发提供一定参考。     

竹笋加工下脚料的利用研究进展

综述了近年来竹笋加工下脚料的利用研究进展,结果表明,竹笋加工下脚料只要经过适当的处理就可以作为食品添加剂或制成保健品,也可以加工成家畜饲料等,是一种重要的自然资源。     

Innovative processes and technologies for modified atmosphere packaging of fresh and fresh-cut fruits and vegetables

Modified atmosphere packaging (MAP) technology has been commercially viable since the 1970s. Currently, MAP is extensively used worldwide to preserve the quality and extend the shelf-life of whole fresh fruits and vegetables, but is also increasingly used to extend the shelf-life of minimally processed fresh fruit and vegetables. This review discusses new processes and technologies that can be used to improve quality preservation and consumer acceptability of minimally processed produce where high respiration rates and challenging degradation processes operate. New packaging innovations are enabling producers and retailers to further maintain quality for longer. Innovative approaches to extend shelf-life include active MAP with differentially permeable films, films that incorporate antimicrobial properties, edible coatings that confer barriers properties, and the use of non-traditional gases to modify respiration. Intelligent packaging using integrated sensor technologies that can indicate maturity, ripeness, respiration rate and spoilage are also appearing. This review demonstrates that preservation technologies and associated packaging developments that can be combined with modified atmosphere are constantly evolving technology platforms. Adoption of combinations of technology improvements will be critical in responding to commercial trends towards more minimally processed fresh-cut and ready-to-eat fruit and vegetable products, which require specialized packaging solutions.     

Modified Atmosphere Packaging of Pomegranate Fruit and Arils: A Review

Ongoing global drive for a healthier diet has led to a rise in demand for convenient and fresh food produce, with high nutritional value and free of additives. Minimally fresh processed fruits and vegetables, satisfies the consumers’ perception of a high nutritional quality and convenience produce. Minimally processed fruit and vegetables are susceptible to increased deterioration in quality and microbial infestation due to increase in endogenous enzymatic processes and respiration rate. Modified atmosphere packaging (MAP) technology offers the possibility to retard produce respiration rate and extend the shelf life of fresh produce. However, it is important to correlate the permeability properties of the packing films with the respiration rate of the produce, in order to avoid anaerobic conditions which could lead into fermentation of produce and accumulation of ethanol. Hence, mathematical prediction modelling is now widely applied in the design and development of effective MAP technology in both whole and minimally processed fresh produce. With increasing global interest in postharvest handling and nutrition value of pomegranate, MAP of minimally processed pomegranate arils offers additional innovative tool for optimal use and value addition, including the utilization of lower-grade fruit with superficial peel defects such as; cracks, splits, and sunburnt. This review paper highlights the current status and applications of modified atmosphere packaging in whole fruit and minimally processed pomegranate arils and identifies future prospects.     

臭氧结合气调包装对毛竹笋的保鲜作用

目的：探讨臭氧水（ozone water,OW）浸泡和臭氧（ozone gas,OG）气熏预处理结合气调包装（modified atmosphere packaging,MAP）对毛竹笋的保鲜效果。方法：毛竹笋经不同预处理和包装处理后,测定其在4 ℃贮藏期间腐烂率、粗纤维质量分数、硬度和多酚氧化酶活力、过氧化物酶活力的变化。结果：未经任何处理的对照组竹笋腐烂率、粗纤维质量分数、硬度均随贮藏时间延长明显增加,在4 ℃下贮藏28 d后,腐烂率为60%,粗纤维质量分数和硬度分别比贮藏初始增加了116.87%和118.82%;与对照组相比,单独气调包装（MAP）、臭氧水浸泡结合气调包装（OW＋MAP）、臭氧气熏结合气调包装（OG＋MAP）均能有效延缓竹笋腐烂和硬化,抑制竹笋多酚氧化酶、过氧化物酶活性;其中,OG（9 μL/L、40 min）＋MAP对竹笋的保鲜效果最佳,该条件处理后的竹笋在4 ℃下贮藏28 d后,腐烂率最低（15%）,且粗纤维质量分数比贮藏初始仅增加了22.69%。结论：臭氧预处理对于竹笋保鲜具有较好的效果,且OG的作用效果优于OW。因此,通过对竹笋进行OG预处理,可以有效延长竹笋的贮藏期。     

超微粉碎对竹笋壳粉理化性质的影响

本文研究了超微粉碎技术对竹笋壳粉的基本组成、物理性质以及对亚硝酸根和胆固醇的吸附能力的影响。结果显示:超微粉碎处理后竹笋壳粉的水分、灰分、蛋白质和膳食纤维含量保持稳定的同时其平均粒径由383.90 μm降至12.69 μm。另外粉体亮度显著提升(p<0.05),红色度和黄色度均显著降低(p<0.05)。竹笋壳超微粉的持水性和持油性无显著变化,溶胀性显著降低(由7.48 mL/g降至5.50 mL/g)(p<0.05)。竹笋壳超微粉对亚硝酸根离子和胆固醇吸附量分别为558.26 μg/g(pH2.0)、346.19 μg/g(pH7.0),吸附能力分别提升了24.6%和9.1%(p<0.05)。傅立叶红外光谱显示超微粉碎对竹笋壳粉中羟基,糖类亚甲基以及木质素中芳香族化合物没有影响。同时扫描电镜观察发现超微粉碎造成粉体颗粒表面呈蜂窝状。故超微粉碎处理能够较好的维持竹笋壳粉的基本组成成分,并改善其理化性质。     

Synergistic Effect of Sodium Chlorite and Edible Coating on Quality Maintenance of Minimally Processed Citrus grandis under Passive and Active MAP

Edible coating has been an innovation within the bioactive packaging concept. The comparative analysis upon the effect of edible coating, sodium chlorite (SC) and their combined application on quality maintenance of minimally processed pomelo (Citrus grandis) fruits during storage at 4 °C was conducted. Results showed that the combination of edible coating and SC dipping delayed the microbial development whereas the sole coating or dipping treatment was less efficient. The synergetic application of edible coating and SC treatment under modified atmosphere packaging (MAP, 10% O₂, 10% CO₂) was able to maintain the total soluble solids level and ascorbic acid content, while reduce the weight loss as well as development of mesophiles and psychrotrophs. Nonetheless, the N, O‐carboxymethyl chitosan solely coated samples showed significantly higher level of weight loss during storage with comparison to the untreated sample. Furthermore, the combined application of edible coating and SC dipping under active MAP best maintained the sensory quality of minimally processed pomelo fruit during storage.