Postharvest management affects spearmint and calamint essential oils

BACKGROUND: The objectives of this work were to evaluate the phytomass yield, essential oil (EO) content and EO yield of Mentha spicata L. var. rubra, M. spicata L. var. viridis and Calamintha nepeta Savi in Piedmont (Italy), and to study how postharvest management (hydrodistillation of EO from fresh, dehumidified or oven‐dried herbs) can affect the EO content and profile of the three species. RESULTS: Mentha spicata L. var. rubra gave the greatest phytomass yield (1997 g m^?2), which was statistically different from M. spicata L. var. viridis and C. nepeta. The highest EO yield was obtained from C. nepeta (3.75 g m^?2), which was significantly different from the Mentha genus. Postharvest management significantly affected both the EO content and the EO profile of each species, with the dehumidifying process leading to a significantly higher EO content than the oven‐drying process. The EO profile was different not only from species to species but also because of the postharvest management. CONCLUSION: The dehumidifying process is a relatively new postharvest technology that has shown positive results in terms of EO yield, and it can be applied to species which have a high EO value, after evaluation of the resulting EO profile. © 2012 Society of Chemical Industry     

猕猴桃果实采后生理、采后病害与保鲜技术研究进展

对国内外关于猕猴桃果实采后生理、采后病害与保鲜技术的研究进展进行综述。采后生理涉及猕猴桃果实采后呼吸强度、乙烯释放、营养成分、果实软化及相关酶类等;果实采后病害包括生理性病害和病理性病害;保鲜技术包括猕猴桃果实的采收、热处理、涂膜处理、钙处理、草酸处理、1-甲基环丙烯（1-MCP）处理、ClO2处理、低温冷藏,及气调贮藏等;指出了猕猴桃果实采后研究存在的问题和今后需要进一步研究的领域。     

库尔勒香梨“黑头病”病原菌的分离和初步鉴定

近年来,库尔勒香梨在贮藏中极易发生一种新型微生物病害--"黑头病"。本文对香梨黑头病病原菌分离、纯化和形态学进行初步鉴定。其结果表明,侵染黑头病香梨的病原菌有七株病原菌,分属于枝孢属(Cladosporium,简称C)、青霉属(Penicillium,简称P)、链格孢属(Alternaria,简称AL)和曲霉属(Aspergillus,简称AS),同时通过致病性实验确定致病菌为真菌界(Fungi)半知菌亚门(Deuteromycotina)丝孢纲(Hyphomycetes)丝孢目(Hyphomycetales)暗色孢科(Dematiaceae)枝孢属(Cladosporium)。     

Quinoa—Postharvest and Commercialization

In 1955, the area of production of quinoa (Chenopodium quinoaWilld.) and cañiwa (Chenopodium pallidicauleAellen) was 32,605 has and the yield was 35,995 t of grain, giving an average yield of 1104 kg/ha (Ministry of Agriculture, 1955). In 1996, 18,704 ha of quinoa and 4392 ha of canihua were sown with a yield of 860 and 680 kg/ha, respectively. In 1955, these crops were the eighth most important crops in Peru, but in 1996, they were no longer among the top 30. Studies of quinoa cultivation in Peru began in 1936, when 100 lines were evaluated, and 12 were selected as the most promising. Since 1940, two of these varieties have been cultivated extensively in Junín, Blanca de Junín, and Rosada de Junín. In 1951, a campaign to encourage cultivation of the two Junin varieties and Real from Bolivia was started in Puno in southern Peru.

During the last few decades, programs have been developed to improve quinoa yields. However, production and productivity have not reached the 1955 level. Undoubtedly, improper postharvest treatment has been a major cause of low yields.     

鲜食核桃果实采后生理与采后病害研究进展

鲜食核桃不仅味道鲜美,而且营养价值很高。因此,深受广大消费者喜爱,近几年的需求呈逐年上长的趋势。但由于其较高的水分含量和脂肪含量,在贮藏过程中易出现发霉、发芽和失水等现象。对国内外鲜食核桃果实的油脂酸败、营养成分变化等采后生理现象以及果皮褐变、微生物病害等采后病害的研究进展进行综述,并对其今后的研究方向进行展望。     

番石榴果实采后生理和采后病害研究进展

番石榴果实采后易腐烂劣变,不耐贮运,制约着中国番石榴产业的进一步发展。本文就国内外关于番石榴果实采后生理和采后病害的研究进展进行综述,指出了番石榴果实采后研究存在的问题和今后需要进一步研究的领域。     

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     

Biocontrol of Postharvest Anthracnose of Mango Fruit with Debaryomyces Nepalensis and Effects on Storage Quality and Postharvest Physiology

Anthracnose is presently recognized as one of the most important postharvest disease of mango worldwide. To control the disease, chemical fungicides for a long time was widely used among fruit farmers, but recently found that pathogen had developed increasingly resistance to it. With people's growing desire of healthy and green food, finding new and environmentally friendly biological control approach was very necessary. In this paper, we provided a kind of new antagonistic yeast which enriched the strain resources and the efficacy of Debaryomyces nepalensis against postharvest anthracnose of mango fruit and the influence on quality parameters were investigated. The results showed that the decay incidence and lesion diameter of postharvest anthracnose of mango treated by D. nepalensis were significantly reduced compared with the control fruit stored at 25 °C for 30 d or at 15 °C for 40 d, and the higher concentration of D. nepalensis was, the better the efficacy of the biocontrol was. Study also found that 1 h was the best treatment duration and antagonistic yeast inoculated earlier had good biocontrol effect on anthracnose. Meanwhile, treatment by D. nepalensis could significantly reduce postharvest anthracnose of mango, delay the decrease in firmness, TSS, TA, and ascorbic acid value, and do not impair surface color during postharvest storage. Moreover, the increase in MDA (malondialdehyde) content and increase in cell membrane permeability of fruit treated by D. nepalensis was highly inhibited. The results suggested D. nepalensis treatment could not only maintain storage quality of mango fruit, but also decrease the decay incidence to anthracnose disease. All these results indicated that D. nepalensis has great potential for development of commercial formulations to control postharvest pathogens of mango fruit.     

Postharvest insect resistance in maize

One of the main challenges for the 21st century is ensuring global food security. Today, maize is the largest staple crop produced worldwide. Postharvest primary insect pests, especially the maize weevil (Sitophilus zeamais) and the large grain borer (Prostephanus truncatus) cause food-grain losses during storage up to 40% of total production, mainly in developing countries. Alternatives for pest management have been explored, including the implementation of hermetic storage structures and the application of chemical insecticides. Nevertheless, in low-income regions, both strategies are rarely accessible to smallholders. Modern breeding programs have endeavored to develop insect-resistant varieties, which diminish postharvest pest losses. In this review, we report the current status and advances in maize kernel-pest interactions, the bases and mechanisms of kernel resistance and their biotechnological perspectives. We demonstrate that the comprehension of resistance mechanisms has been fundamental for the development of new productive and resistant varieties, representing a sustainable alternative for developing countries. Finally, we analyse the biotechnological perspectives of natural kernel resistance in global food security.     

3种鲜枣贮藏期致病真菌的检测及定性研究

鲜枣采后贮藏期间易发生病害而腐烂。为深入研究危害采后鲜枣的主要病原菌和发病原因,以天津静海所产梨枣、圆铃枣、冬枣3个品种鲜枣为试材,对采后低温贮藏后期的病原菌进行了分离和鉴定,并对其生物学性质进行了初步研究。结果表明,侵染梨枣的病原菌主要有根霉和交链孢。侵染圆铃枣的病原菌是交链孢,但主要表现为生理性病害酒化。侵染冬枣的病原菌主要是交链孢和裸孢壳菌。     

Effects of fungal interactions among Fusarium head blight pathogens on disease development and mycotoxin accumulation

Published research on the effects of fungal interaction on disease development and subsequent mycotoxin accumulation was reviewed, focusing on pathogens related to Fusarium Head Blight (FHB). Almost all published studies showed that competitive interactions are the rule when fungal/disease development is considered. The fungi with the competitive advantage did not usually colonise significantly more than when inoculated alone, i.e. there was no advantage gained by the dominant pathogen from the presence of other weaker competing fungi. However, the effects of fungal interactions on mycotoxin accumulation were generally more complicated. Total mycotoxin production in mixed inoculation may decrease, increase or remain at a similar level compared with single-isolate inoculation, depending on the fungal species concerned and environmental conditions. However, the lack of accurate quantification of each competing fungal component in mixed inoculations in many studies prevented an accurate estimation of mycotoxin productivity per unit fungal biomass. A few recent studies, where each individual fungal component was quantified using molecular methods, suggested that mycotoxin productivity in mixed inoculations generally increased.     

采后赤霉素处理对低温贮藏期间枸杞鲜果腐烂的抑制和品质的影响

为降低枸杞鲜果在低温结合塑料薄膜包装条件下的腐烂率,作者以"宁杞1号"鲜果为试材,通过0.025 g/L和0.05 g/L赤霉素(GA3)浸泡处理3 min,观察果实在聚乙烯薄膜包装条件下低温(0±1)℃贮藏期间的防腐保鲜效果。结果表明:GA3处理可有效降低果实的腐烂率,贮藏24d时,0.05 g/L处理者的腐烂率为对照的一半。GA3还可明显延缓贮藏期间可溶性固形物质量分数的降低,在一定程度上维持可滴定酸含量,但对果实的失重率无影响。经0.05 g/L GA3处理的果实在贮藏30 d时仍具有新鲜枸杞固有的风味,较好地保持了果柄的新鲜度。由此表明,GA3可通过延缓果实衰老、维持抗性来降低枸杞贮藏期间的腐烂率,维持良好的品质。     

沙葱采后贮藏保鲜效果研究

目的 分析沙葱采后贮藏的特性, 建立沙葱的采后高效保鲜方法。方法 通过Spurr树脂半薄切片的方法观察沙葱的组织结构, 利用低温冷库摸索沙葱采后最适贮藏温度, 研究硬质塑料盒、硬纸盒和塑料筐等包装形式对沙葱采后保鲜的影响, 研究不同的气体组分对沙葱采后保鲜效果的影响。结果 通过对沙葱组织树脂切片的显微观察, 发现沙葱的木质部细胞壁较薄, 组织纤维化程度较低, 这导致其质地脆嫩、口感上乘, 但是同时导致其易出现失水、断节和腐烂等现象。结果表明0 ℃是贮藏沙葱的最佳温度, 在此温度下保鲜期可达15 d。沙葱通过硬质纸盒内衬软质硫酸纸包装, 常温下保鲜期可达到4 d。4% CO2+2% O2的气调组分可以有效延长沙葱的采后保鲜期, 常温保鲜期可达7 d。结论 0 ℃是沙葱最佳采后贮藏温度; 硬质纸盒内衬软质硫酸纸包装形式有利于沙葱采后贮藏; 4% CO2+2% O2是沙葱最佳气调贮藏条件。     

Postharvest application effect of agave fructans on anthracnose disease,defense-related enzyme activities,and quality attributes in avocado fruit

Food Science and Biotechnology - The postharvest application of high degree of polymerization agave fructans (HDPAF) was tested, evaluating anthracnose disease, defense-related enzyme activities,...     

Postharvest BTH treatment induced disease resistance and enhanced reactive oxygen species metabolism in muskmelon (Cucumis melo L.) fruit

Benzo (1, 2, 3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH) is a novel synthetic elicitor capable of inducing disease resistance in many plants. Fruits were dipped in BTH at 100?mg/L for 10?min, and then stored at room temperature (22?±?2?°C, relative humidity 55–60?%). The results showed that BTH significantly (P?<?0.05) reduced the lesion area of fruits inoculated with Trichothecium roseum and the natural disease incidence of fruits during storage at room temperature. The treatment effectively maintained cell membrane integrity and decreased the production of lipid peroxidation and malondialdehyde. BTH treatment markedly enhanced the accumulation of hydrogen peroxide, (H₂O₂) while decreased the rate of superoxide anion (O ₂ ^·? ) production. Furthermore, BTH observably increased the activities of NADPH oxidase (NOX, EC1.6.3.1), superoxide dismutase (SOD, EC1.15.1.1), peroxidase (POD, EC1.11.1.7), ascorbate peroxidase (APX, EC1.11.1.11), and glutathione reductase (GR, EC1.6.4.2), while inhibited the catalase (CAT, EC1.11.1.6) activity. These results indicated that BTH treatment increased the disease resistance of muskmelon fruits by enhancing their antioxidant system activity after harvest, and suggested that postharvest treatment with BTH could be promising in reducing decay and reducing or/and substituting chemical fungicides to control postharvest diseases in fruits.     

Postharvest Ripening Characterization of Greenhouse Tomatoes

The determination of °Brix, pH, titratable acidity and antioxidant composition such as β-carotene, lycopene, and vitamin C was done in greenhouse “Savoura” tomatoes during maturation. The chromatic values L*, a*, b* were determined at the top surface of the tomato, and its strength-deformation curve was tested with a texturometer. Results pointed out that °Brix and titratable acidity did not change during postharvest, while β-carotene, lycopene, and vitamin C contents increased continuously toward the red stage of tomato. The colour values L*, a*, b*, and ratio a*/b* had a good correlation with the maturity stages. Also, a high correlation between lycopene content and (a*/b*) ratio was found, which was well represented with a second order polynomial function (r² = 0.95). This equation permits to appropriately estimate lycopene content of tomato as a function of its color, without any chemical analysis. During ripening, tomato texture changed from firm turgid to soft and the puncture deformation degree increased. Tomato firmness and chromatic values had a good correlation, and the lycopene content was a logarithm function of firmness (r² = 0.81). The strength in puncture test increased linearly with deformation until the bioyield point. The measured force was analyzed as the sum of the compression and the shear forces. The two force coefficients can be considered as tomato properties, independent of the puncture probe. These coefficients were found to decrease during tomato maturation.     

果胶降解与采后果实质地变化研究进展

果胶是高等植物细胞壁的重要组成成分,对于维持细胞结构起着重要作用。果胶与果实成熟软化过程中质地变化密切相关。本文综述了果胶的一般化学结构、结构模型、采后果实果胶的含量与组分变化、中性糖组成与多聚物纳米结构的变化,总结了采后不同质地变化类型果实的果胶降解模式,为深入认识果胶代谢在不同质地变化类型果实中的作用提供参考。     

Mushroom Response to Postharvest Hyperbaric Storage

Vessels suitable for storing mushrooms [Agaricus bisporus (Lange) Singe] at absolute pressures to 35 atm were constructed from 43 liter (1A) gas cylinders and plumbed for conducting static or continuous-flow experiments. Neither pressurization nor gradual depressurization over 6 hr injured mushrooms. Pressure did not affect respiration, but significantly reduced moisture loss during storage. Mushrooms depleted O₂ to very low levels and showed high tolerance to CO₂. Pressure was used to safely increase CO partial pressure (p) 35-fold. At 0.035p, CO reduced mushroom browning but not respiration. A completely autonomous storage system with CO₂ removal and automatic O₂, replenishment was developed.