可食性复合涂膜对芒果货架期生理品质的影响

以壳聚糖和可食性淀粉为成膜剂,添加有机酸等亲水性助剂,配制3种可食性复合膜(M1、M2和M3),研究(20±0.5)℃条件货架期内不同可食性复合涂膜处理(以蒸馏水浸泡做空白对照)对芒果转黄率、转色指数、腐烂率、呼吸强度、硬度、质量损失率、可溶性固形物含量(soluble solid content,SSC)、维生素C(VC)和多酚氧化酶(polyphenol oxidase,PPO)活性等生理指标的影响。结果表明：芒果货架期期间,涂膜处理可以有效地抑制果实转黄和腐烂,推迟果实呼吸高峰的到来,显著降低芒果果实的转色指数和软化程度,提高果实硬度。同时,M3处理还可较好地保持果实的质地,有效减缓果实SSC上升的速度和幅度,维持果实较高的VC含量,但对果实PPO活性的抑制与其他涂膜处理间差异不显著。研究表明,涂膜处理可以显著改善芒果货架期期间品质劣变情况,尤以M3涂膜处理效果最好。     

箱式气调对甜樱桃贮藏及货架品质的影响

为研究自发气调保鲜技术对甜樱桃贮藏效果的影响,以莎米托、菊红、拉宾斯、雷尼为试材,分析它们贮藏期及货架2 d后果实品质变化规律。试验结果表明,应用塑料箱式气调保鲜技术后,甜樱桃果实贮藏期延长,莎米托、菊红贮藏56 d,拉宾斯、雷尼贮藏49 d时,货架期果实品质仍呈缓慢下降趋势,尚具有商品及食用价值,之后果实硬度、可滴定酸度下降迅速,果柄保鲜指数、果皮褐变指数加重。     

Edible Coating Effects on Storage Life and Quality of Tomatoes

Tomatoes at breaker and pink stage maturities were coated with comzein film. Color, weight and firmness changes and sensory quality were compared with noncoated tomatoes during storage at 21°C. Corn-zein fdm delayed color change and loss of firmness and weight during storage. Shelf life was extended by 6 days with film coatings as determined by sensory evaluation.     

Minimal Processing and Edible Coating Effects on Composition and Sensory Quality of Mini-peeled Carrots

Coating treatment did not affect fresh carrot flavor or aroma, sweetness, bitterness, harshness or taste preference. Total terpenoids declined 72% after 17 days storage, with the major loss occurring within 3 days after minimal processing. α- and β-carotene declined 18% and 14% within 3 days after minimal processing with no further loss. Peel tissue contained less β-carotene than phloem tissue, and its removal was not responsible for loss of β-carotene. The edible coating did not affect terpenoid or carotene content.     

Effects of Gellan-Based Edible Coating on the Quality of Fresh-Cut Pineapple During Cold Storage

The effects of gellan-based [gellan gum 0.56 % (w/v), glycerol 0.89 % (w/v) and sunflower oil 0.025 % (w/v)] edible coating on the respiration rate, physico-chemical properties and microbiological and sensory quality of fresh-cut pineapple during 16 days of storage (5?±?1 °C, 85?±?10 % RH) were evaluated. Uncoated fresh-cut pineapple was stored under the same condition and served as the control. For cross-linking reaction which was necessary for gel formation of gellan gum, a 2 % (w/v) calcium chloride solution that contained 1 % (w/v) ascorbic acid and 1 % (w/v) citric acid (as antibrowning agents) was used. The results obtained show that the respiration rate and weight loss of gellan-based coated samples were significantly (p?<?0.05) lower than those of the uncoated samples during 16 days of storage at 5 °C. In addition, coated samples significantly (p?<?0.05) maintained the firmness and colour of fresh-cut pineapple during low-temperature storage as compared to uncoated samples. The results obtained in this study also indicate that pH, titratable acidity and total soluble solids of coated and uncoated samples showed little changes during 16 days of storage at 5 °C. Gellan-based formulation did not show any antimicrobial effect, and no significant (p?>?0.05) differences were found among total plate counts and yeast and mould counts for coated and uncoated samples. Total plate counts and yeast and mould counts for coated and uncoated samples reached 10⁶ CFU/g (limit of shelf life acceptance for fruit-based products recommended by the Institute of Food Science and Technology in the UK) after 12 days of storage at 5 °C. In addition, the scores for all sensory characteristics at day 12 were significantly (p?<?0.05) higher in coated samples as compared to control. Therefore, the results obtained in this study indicate that gellan-based edible coating formulation has the potential to maintain the quality of fresh-cut pineapple during low-temperature storage for about 12 days.     

不同采收期对南果梨常温货架贮藏品质的影响

本实验采用盛花标记法研究不同采收期对南果梨常温货架品质的影响。结果表明：随着采收期增加,果实单果重、种子转色指数、可溶性固形物含量、丙二醛含量、可溶性果胶含量增加,果实硬度、可滴定酸含量、原果胶含量、淀粉含量降低;常温货架期间,盛花后140d 果实呼吸强度、腐烂率和果胶酶、淀粉酶活性均小于其它两个采收期,盛花后140d 为南果梨较适宜采收期。     

香辛料保鲜液与壳聚糖淀粉复合膜在冷却肉保鲜中的应用

利用不同配比的壳聚糖与淀粉复合制备可食性膜,测定了膜的厚度、水溶性和透光率等特性,优选出膜薄、水溶性小、透光率强的复合膜,并与香辛料提取液复合对冷却猪肉进行保鲜处理。结果表明:在其他条件相同时,复合膜中壳聚糖的比例越大,保鲜效果越好。在4℃条件下,冷却肉贮藏第28d时,保鲜液与壳聚糖淀粉复合膜处理的冷却肉保鲜效果好,并与对照组差异显著。当壳聚糖:淀粉为9:1时,各测定的保鲜指标分别是:细菌总数的对数值为4.98、汁液流失率为1.59%、红度值为17.86、TVB-N值为17.91mg/100g,即冷却猪肉处于鲜肉状态,肉色鲜红。     

Edible Coating Effects on Postharvest Quality of Green Bell Peppers

Green bell pepper fruits (Capsicum annuum L., cv. “Jupiter”) were coated with a mineral-oil-based coating or a cellulose-based coating. Three different milk-protein-based edible coatings (whey protein isolate, sodium caseinate, and sodium caseinate beeswax emulsion) plasticized with glycerol were also tested. The effects of these coatings were followed by measurement of changes in respiration, internal gases, color, firmness, and water loss during storage at 10°C, 80–85% RH for 20 days. None reduced respiration or affected color. Only the mineral-oil-based coating significantly reduced moisture loss, thus maintaining fruit firmness and thereby prolonging fruit freshness.     

3种处理方式对冬枣货架期品质的影响

以冬枣为试材,研究3种处理方式对其货架期品质的影响。通过测定冬枣的呼吸强度、硬度、总可溶性固形物、VC、乙烯释放量、乙醇积累等指标,研究热水浸泡、1-MCP熏蒸、纳米袋包装3种处理对冬枣果实的保鲜效果。结果表明:3种处理方法均不同程度保持了枣果货架期品质,其中纳米袋包装保鲜效果最佳,有效维持了冬枣果肉硬度和VC含量,延缓其色泽由绿到红的转变和总可溶性固形物上升,抑制了冬枣的呼吸强度及乙烯和乙醇的产生,货架期15d后,仍具有商品价值。     

儿茶素对虾滑贮藏和食用品质的影响

为研究儿茶素添加量对虾滑贮藏期间脂肪和蛋白质氧化、微生物侵染程度、色泽以及硬度的影响,以不同时间点样品所含过氧化值（peroxide value,POV）和硫代巴比妥酸（thiobarbituric acid,TBA）值、蛋白质的羰基和巯基含量（质量摩尔浓度）分析儿茶素对虾滑脂肪和蛋白质氧化的抑制作用,以挥发性盐基氮（volatile base nitrogen,TVB-N）值和菌落总数表征微生物对虾滑的侵染程度,以虾滑白度、硬度、pH和感官评分来判断虾滑食用品质的变化。结果显示,儿茶素的添加能够延缓虾滑POV、TBA值、羰基质量摩尔浓度的升高以及巯基质量摩尔浓度的下降,抑制微生物生长繁殖;贮藏期间虾滑的白度值呈先上升后下降的趋势,硬度呈上升趋势,pH无显著变化。结果表明,儿茶素添加量在0.20 g/kg及以上时,能够改善虾滑贮藏期间的品质,具有较好的应用前景。     

Color Stability of Edible Coatings During Prolonged Storage

ABSTRACT: The yellowing rates of edible coatings were determined at 23, 40, and 55 °C at 75% relative humidity (RH). Whey protein isolate (WPI) coatings had lower yellowing rates than whey protein concentrate (WPC) and the same rates as shellac coatings. Hydroxypropyl methylcellulose (HPMC) coatings had the lowest yellowing rates. Zein coatings became less yellow during storage; however, their color was still pronounced. Activation energies and Q₁₀ values for the yellowing of whey protein coatings were similar to those previously reported for the browning of whey powder. The results indicate that WPI coatings can be used in place of shellac coatings when low-color development is desired. WPC coatings can be used to tailor color development of a food.     

可食性膜对油豆角贮藏期间品质的影响

采用正交实验设计配制保鲜剂 ,测定经处理的油豆角在贮藏期间水分及营养成分的变化 ,探讨油豆角贮藏期间品质的变化规律 ,结果表明 :随着贮藏时间的延长 ,油豆角中水分、Vc和还原糖的含量不断下降 ;叶绿素的含量初期下降 ,随后升高并出现累积峰 ,最后又趋于降低。     

纤维素可食性膜对番茄保鲜贮藏中硬度和色泽的影响

用于食品包装的绿色包装材料之一的可食性包装已逐渐地取代容易产生“白色污染”的不可降解性塑料薄膜。本研究采用羟丙基甲基纤维素 (HPMC)可食性膜 ,将之涂于番茄上 ,然后贮藏于 2 0℃下达 18d ,研究其对番茄硬度和色泽的影响。在贮藏期间 ,所有处理组的番茄的硬度都随着贮放时间的延长而下降。但是 ,施用HPMC可食性膜可以延缓番茄变软。在贮藏日的第 7、13和 18d ,观察到以HPMC涂膜的番茄的硬度都显著性地 (P≤ 0 0 5 )比未涂膜的番茄的硬度大。本研究还证实了HPMC可食性膜可以显著性地 (P≤ 0 0 5 )延缓番茄在 2 0℃贮藏时色泽的变化 ,延迟了番茄从粉红色到红色阶段的后熟。因此 ,HPMC可食性膜可以有效地减慢番茄后熟 ,延长番茄的保存期。同时番茄硬度损失率的减慢 ,可以减少番茄果实运输时因机械损伤导致果实腐败而造成的经济损失。     

Sensory, Microbiological and Chemical Quality of Mini-Peeled Carrots as Affected by Edible Coating Treatment

The effect of three application rates of an edible cellulose-based coating on sensory, microbiological and chemical quality of mini-peeled carrots was studied during storage at 2°C. Carrots treated with edible coating had reduced levels of white surface discoloration, and higher sensory scores for orange color intensity, fresh carrot aroma, fresh carrot flavor, and overall acceptability than non-coated carrots. Edible coating treatment did not affect levels of total aerobic microorganisms, yeast, mold or lactobacilli. Oxygen, carbon dioxide and ethanol levels in packages, and sugar and soluble phenolic content of mini-peeled carrots were not affected by coating treatment. An edible coating application rate of 0.23–0.49 L/min protected against surface discoloration and retained quality during storage at 2°C.     

6-BA和热处理对食荚豌豆贮藏品质的影响

6-BA和热处理是绿色无污染的果蔬保鲜技术。对食荚豌豆采用15ml/L 6-BA溶液或40℃热水处理后,置于1℃环境中贮存,不仅可降低食荚豌豆呼吸强度、豆荚腐烂的发生,同时还可抑制POD、PPO活性与MDA生成、豆荚粗纤维含量增长,从而起到延缓豆荚衰老和品质下降的作用。6-BA处理能保持较高的VC、叶绿素和水分含量,保鲜效果优于热处理。     

氧化玉米淀粉涂膜对低温贮藏期间甜樱桃生理及品质的影响

以“红灯”甜樱桃为材料,研究在采后0 ℃和7 ℃条件下氧化玉米淀粉涂膜对果实保鲜效果的影响。结果表明,氧化玉米淀粉涂膜可有效延缓低温贮藏期间甜樱桃果实的质量损失率和呼吸强度,降低细胞膜透率,抑制丙二醛的积累。此外,氧化玉米淀粉涂膜还可有效维持果实的可溶性固形物、可滴定酸、抗坏血酸（VC）含量,保持果实的外观、风味和口感;0 ℃条件下涂膜处理的保鲜效果要显著优于7 ℃。由此表明,氧化玉米淀粉涂膜可有效延缓冷藏期间甜樱桃果实的成熟衰老,最大限度地保持果实品质,可作为新型的果蔬涂膜材料,应用于水果、蔬菜的实践采后保鲜过程。     

壳聚糖可食用膜对辣椒贮藏生理的影响

研究了10℃时不同浓度壳聚糖可食用膜对辣椒贮藏生理指标的影响,结果表明:壳聚糖可食用膜处理能够明显降低呼吸强度,抑制叶绿素降解,减少贮藏期间辣椒组织中丙二醛的产生,减缓Vc含量以及超氧化物歧化酶活性的降低,延缓辣椒果实的衰老进程.     

Effect of Edible Coating Process and Irradiation Treatment of Strawberry fragaria spp. on Storage-keeping Quality

ABSTRACT: Gamma-irradiation and various edible coatings were tested on fresh strawberries ( Fragaria spp. ) for keeping fruit quality and extending shelf life. Four coatings based on milk protein were evaluated. In 1 experiment, coating formulation based on caseinate and/or strawberries were irradiated using a ⁶⁰Co source. Both gamma-irradiation treatment and edible coating process significantly delayed (p ≤ 0.05) molds growth. Edible coating based on irradiated caseinate was more effective than that of unirradiated caseinate. In a 2nd experiment, 3 irradiated coatings based on calcium caseinate and whey proteins were evaluated. The coating formulation based on 1:1 caseinate-whey was found to be more effective than those based on calcium caseinate. Addition of calcium chloride or a mixture of pectin and agar increased the effectiveness of the coating by delaying molds' apparition.     

壳聚糖可食用膜对油豆角贮藏生理的影响

使用壳聚糖配制的涂膜液处理油豆角,通过测定涂膜的油豆角在贮藏期间呼吸强度、PPO、POD、MDA的变化,探讨油豆角在贮藏期间的生理变化规律.结果表明,涂膜处理后能推迟油豆角呼吸高峰的到来;同时,在贮藏期间,涂膜油豆角的呼吸强度、PPO、POD、MDA与对照组相比都有所降低.