Reduction of chilling injury in ripe Alphonso mango fruit in cold storage by temperature conditioning

The influence of ripening temperature and cold conditioning of pre-climacteric fruits on the incidence of chilling injury (CI) in ripe mango fruits cv. Alphonso during refrigerated storage was investigated. Fruits previously held and ripened at tropical ambient temperature (AT, 27–34°C) developed CI (skin staining or browning) when ripe fruits were subsequently stored at 5, 10, or 15°C for shelf-life extension. Fruits held and ripened at 20°C1°C, RH 85–90% showed little evidence of CI when subsequently stored at 5 or 10°C up to 14 days. Chilling injury in ripe mangoes was also avoided by holding pre-climacteric fruits for a minimum period of 30 days at 10°C and then ripening them at 27–34°C. The quality of the ripe mangoes remained good during cold storage for 7 days and were acceptable until 10–14 days with minimal changes in texture, flesh colour, carotenoids, total soluble solids, titratable acids and ascorbic acid. Shelf-life of ripe mangoes can thus be extended under refrigeration by pre-storage conditioning.     

6个芒果品种品质特性评价研究

对台农一号、紫花、桂七、凯特、马切苏和三年芒6个品种芒果原浆的色泽、口感滋味及物理特征进行了评价,分析了包括可溶性固形物、可滴定酸度、pH、总糖、胡萝卜素、抗坏血酸、黏度以及色泽等与芒果原浆品质特性相关的物理和生化指标。基于SPSS统计分析软件对测定指标进行了因子分析,比较了不同芒果品种品质特性的差异性,并与国外优良品种品质进行比较。结果表明,台农一号、凯特、马切苏口感品质较为适宜,马切苏和三年芒营养素含量最为丰富,凯特和紫花色泽品质较佳。中国芒果品种整体品质低于国外品种。     

Improving the nutraceutical value of mango during ripening by postharvest irradiation with blue LEDs via enhancing of antioxidant enzyme activities

Light-emitting diodes (LEDs) are emerging as a clean technology for improving the postharvest preservation of fruits. Mangoes were irradiated with blue LEDs (75 µmol s^-1 m⁻²) and then stored for 15 days. The fruit quality, including the content of antioxidant compounds and activities of antioxidant enzymes, was evaluated during storage. The treatment with blue LEDs delayed the changes associated with the senescence processes, including the changes in softening, weight loss, total soluble solids content, and titratable acidity. Treatment also caused increases in the antioxidant capacity (1.33-fold), ascorbic acid (1.69-fold), total phenolic (1.33-fold), flavonoids (1.50-fold), and carotenoids content (1.18-fold) compared to control. At the end of storage, blue LEDs treatment maintained higher phenylalanine ammonia-lyase (1.28-fold), peroxidase (1.58-fold), catalase (2.21-fold), and ascorbate peroxidase (1.51-fold) activities. Our findings indicate that blue LEDs might be a potential elicitor that modulates oxidative homeostasis and improves the antioxidant and nutritional status of mango by enhancing the activity of antioxidant enzymes.     

Regulation of the levels of health promoting compounds: lupeol,mangiferin and phenolic acids in the pulp and peel of mango fruit: a review

There is a demand for feasible methodologies that can increase/maintain the levels of health-promoting phytochemicals in horticultural produce, due to strong evidence that these compounds can reduce risk of chronic diseases. Mango (Mangifera indica L.), ranks fifth among the most cultivated fruit crops in the world, is naturally rich in phytochemicals such as lupeol, mangiferin and phenolic acids (e.g. gallic acid, chlorogenic acid and vanillic acid). Yet, there is still much scope for up-regulating the levels of these compounds in mango fruit through manipulation of different preharvest and postharvest practices that affect their biosynthesis and degradation. The process of ripening, harvest maturity, physical and chemical elicitor treatments such as low temperature stress, methyl jasmonate (MeJA), salicylic acid (SA) and nitric oxide (NO) and the availability of enzyme cofactors (Mg²⁺, Mn²⁺ and Fe²⁺) required in terpenoid biosynthesis were identified as potential determinants of the concentration of health-promoting compounds in mango fruit. The effectiveness of these preharvest and postharvest approaches in regulating the levels of lupeol, mangiferin and phenolic acids in the pulp and peel of mango fruit will be discussed. In general spray application of 0.2% iron(II) sulphate (FeSO₄) 30 days before harvest, harvest at sprung stage, storage of mature green fruit at 5 °C for 12 days prior to ripening, fumigation of mature green fruit with 10⁻⁵ mol L⁻¹ and/or 10⁻⁴ mol L⁻¹ MeJA for 24 h or 20 and/or 40 µL L⁻¹ NO for 2 h upregulate the levels of lupeol, mangiferin and phenolic acids in pulp and peel of ripe mango fruit. © 2019 Society of Chemical Industry     

Phenolic compounds and antioxidant capacity of Brazilian mango (Mangifera indica L.) varieties

Phenolic compounds and antioxidant activities of four mango varieties cultivated in Brazil were analyzed. The profile of flavonol-O-glycosides and xanthone-C-glycosides was characterized in pulps from Haden, Tommy Atkins, Palmer, and Ubá cultivars and in the agro-industrial residues from Ubá variety by LC–ESI–MS analysis. The first three varieties were collected from conventional production, whereas Ubá was obtained from organic production. The total phenolic content of the peels and seed kernel extracts was analyzed utilizing Folin-Ciocalteu’s reagent. The aqueous-methanolic extracts of pulp, peel and seed kernels were analyzed for antioxidant activity (AA) by free radical-scavenging and reducing power. A total of 12 flavonoids and xanthones were identified in the pulps, peels and seed kernels, with larger amounts of these compounds being present in the organically grown Ubá variety. The Ubá mango pulp presented higher AA and the peel and seed kernel extracts showed higher AA than did a commercial standard.     

Surface treatments and coatings to maintain fresh‐cut mango quality in storage

BACKGROUND: Edible coatings may extend fresh‐cut fruit storage by preventing moisture loss and decreasing gas exchange. This study evaluated the effect of an antibrowning dip (calcium ascorbate, citric acid and N‐acetyl‐L ‐cysteine), followed or not with carboxymethylcellulose (CMC) or carrageenan coatings on quality of fresh‐cut mangoes stored at 5 °C for up to 20 days. A fourth treatment, only used in one of four experiments, consisted of chitosan. Treatments were applied on ‘Tommy Atkins’, ‘Kent’ and ‘Keitt’ mangoes harvested from Homestead (FL), and on imported store‐bought mangoes. RESULTS: The antibrowning dips maintained the best visual quality during storage for all cultivars, as indicated by higher b*, hue and L*. The CMC coating maintained similar visual quality, but carrageenan or chitosan decreased L* and b*. The antibrowning dip containing calcium ascorbate reduced firmness loss on cut pieces of ‘Keitt’, ‘Kent’ and store‐bought mangoes. The antibrowning treatment maintained higher titratable acidity for ‘Kent’ and ‘Keitt’, resulting in lower sensory sweetness. CONCLUSION: This study with repeated experiments showed that calcium ascorbate with citric acid and N‐acetyl‐L ‐cysteine maintained cut mango slices attractiveness in storage by keeping light color in both varieties. The addition of a polysaccharide coating did not consistently improve quality. Published in 2010 by John Wiley & Sons, Ltd.     

Use of UV-C irradiation to prevent decay and maintain postharvest quality of ripe 'Tommy Atkins' mangoes

Ripe mangoes 'Tommy Atkins' were exposed to UV-C irradiation for 10 and 20 min, prior to storage for 14 days at 5 or 20 °C and a shelf-life period of 7 days at 20 °C. UV-C-treated fruit maintained better visual appearance than unirradiated controls. UV-C irradiation for 10 min was the most effective regime in suppressing decay symptoms and maintaining firmness during storage at 5 or 20 °C. Such fruit (treated with UV-C for 10 min) showed greater levels of putrescine and spermidine after cold storage than controls and those treated with UV-C for 20 min. Higher levels of sugars and lower levels of organic acids were observed in mangoes treated with UV-C for 20 min. However, the most effective UV-C treatment (10 min) for reducing decay maintained sugar and organic acid levels similar to the controls. No UV-damage was observed on treated fruits after storage. These results indicate that UV-C irradiation could be used as an effective and rapid method to preserve the postharvest life of ripe mangoes without adversely affecting certain quality attributes.     

Post-harvest ripening in wax-coated Bocado mango

The effect of three different concentrations of two commercial wax coatings on some parameters of post-harvest ripening was evaluated. The rate of loss of fresh weight of mangoes was reduced with both waxes at higher concentrations Chlorophyll degradation of the exocarp (skin) and the increase in mesocarp (flesh) pH normally occurring during ripening was retarded at higher concentrations of both wax coatings. However Primafresh 31 was less effective than Primafresh C at similar treatment concentrations. The results showed that the delayed ripening effects of wax-coated fruits affected fresh weight loss, exocarp chlorophyll degradation and mesocarp pH change but did not affect mesocarp chlorophyll, sugar, and starch content.     

激发子诱导果实采后病程相关基因的研究进展

果实采后因病原菌的侵染而造成的损失非常巨大。在控制果实采后病害的研究中,利用激发子来诱导果实产生抗性,逐渐成为果实采后病害防治中一种安全高效的保鲜方法,是当前采后病理学、生理学的研究热点。根据激发子的来源可分为生物型和非生物型,据报道它们可以诱导宿主表达病程相关蛋白而对病原菌产生抗性。病程相关蛋白,是由宿主自身病程相关基因转录而表达的,报道的病程相关蛋白基因在很多水果中被定位、克隆,为具体地认知某一个PR基因提供了有力依据。但果实采后PR基因并不是一个基因在起作用,是整体而系统的作用,它们具有遗传特性,并且受到各种因子的调控,因此系统研究果实采后病程相关基因备受重视。随着RNA高通量测序技术在转录组学中的应用,从转录水平上来研究整个PR基因mRNA转录,从而显示某些PR基因上调或下调。本文综述了激发子对PR基因诱导的研究进展,以及转录组学技术在果实采后PR转录水平上的应用。      

A study of factors affecting in-situ De-esterification of mango (Mangifera indica) pectin

De-esterification of mango peel pectin in situ by the action of the enzyme pectinesterase (PE) has been investigated. The rate of enzymic deesterification was highest between pH 8.5 and 9.5 with chemical deesterification also being important. In-situ PE activity declined with fruit ripening but remained relatively constant when assayed on citrus pectin. The most likely explanation for this difference is a change in suitability of the pectin substrate within the fruit during ripening. A reduction in the degree of esterification (DE) of the pectin to 36-42% was obtained following incubation of the mango peels at pH 8.5 for 90 min. A crude preparation of exogenous PE from mango peel and lime pulp was incubated at pH 8.5 with heat-treated (PE inactive) peel as a means of increasing the rate and extent of de-esterification. The PE activity of both these exogenous enzyme preparations was lower on the peel than that of the in-situ mango enzyme, but considerably higher on a hot-water-soluble fraction extracted from the peel. It is suggested that enzyme solubility and pectin accessibility are the major factors affecting in-situ de-esterification of pectin in mango peel.     

Changes in volatile composition during fruit development and ripening of ‘Alphonso’ mango

BACKGROUND: Volatile blends of five developing and five ripening stages of mango (Mangifera indica L. cv. Alphonso) were investigated along with those of flowers and leaves. Raw and ripe fruits of cv. Sabja were also used for comparison. RESULTS: A total of 55 volatiles belonging to various chemical classes such as aldehydes, alcohols, mono‐ and sesquiterpene hydrocarbons, lactones and furanones were identified. In all Alphonso tissues monoterpenes quantitatively dominated, with 57–99% contribution; in particular, (Z)‐ocimene was found in the highest amount. Ripeness was characterized by the de novo appearance of lactones and furanones in the blend of monoterpenes. Sabja was distinguished by the abundance of monoterpene hydrocarbons in the raw fruit, and that of sesquiterpene hydrocarbons and their derivatives in the ripe stage. CONCLUSION: Various stages of the Alphonso fruit during transition from flower to ripe fruit are characterized by unique volatile signatures that are distinguished from each other by the qualitative and quantitative appearance of different volatile compounds. Thus volatiles can be highly informative markers while studying the development and ripening of mango. Copyright © 2009 Society of Chemical Industry     

Leaf:fruit ratio and irrigation supply affect seasonal changes in minerals,organic acids and sugars of mango fruit

To determine the effects of assimilate and water supply on the determination of mango fruit quality, the seasonal variations of minerals, acids and sugar concentrations were investigated over two successive years. To manipulate the assimilate supply, selected branches were girdled to provide ratios of 10, 25, 50 and 100 leaves per fruit. Irrigation was managed to provide two types of water supply treatments. Fruit growth rate was greater when increasing the leaf:fruit ratio. Structural dry matter content and total dry matter content of flesh were higher in fruit with higher leaf:fruit ratios. Treatments had no effect on the structural to total dry matter ratio of flesh. Potassium and magnesium to structural dry weight ratios were not affected by treatments, whereas the calcium to structural dry weight ratio was higher in the flesh of fruit grown under low leaf:fruit ratios. Low assimilate supply increased the ratios of malic and citric acid to structural dry weight. This treatment had little effect on acid concentrations. Glucose and fructose to structural dry weight ratios were higher when assimilate supply was lower. Low leaf:fruit ratios increased fructose concentration but not glucose concentration. Irrigation treatment strongly affected fructose concentration. Sucrose concentration, based either on structural dry matter or on fresh matter, was significantly increased by higher leaf‐to‐fruit ratios. When the fruit was close to maturity, levels of sucrose storage and starch breakdown were positively correlated with assimilate supply. Levels of starch breakdown were correlated with irrigation supply. The effects of these treatments on sugar concentrations may change fruit taste. Copyright © 2004 Society of Chemical Industry     

Quality improvement of non-sulphited mango slices by drying at high temperatures

An optimum drying routine for producing non-sulphited mango slices has been developed. The interaction of essential drying parameters (air temperature, air velocity, dew point, slice thickness and drying time) on water activity (a_W) and browning was determined. Microbiological stability of the dried product was achieved at a moisture content of 17% wet base (w.b.) corresponding to a_W = 0.6. Browning was monitored by the red colour shade of the product (CIE-Lab chromaticity coordinate a*). Drying air temperature and drying time were shown to be the primary factors influencing product colour and a_W. In contrast to common practice, drying for about 6 h at elevated air temperature (80 °C), instead of 50 or 60 °C for a longer time, was optimal, since significant colour changes of the mango slices were not observed even without the use of any chemical or thermal pre-treatment. Moreover, at increased temperature, drying time was considerably shortened from about 9 h to 6 h, resulting in significant extension of the drying capacity.

Industrial Relevance

The suggested process concept for dried mango slices based on high-temperature drying is of utmost significance for the international marketing of dried fruit products. Chemical pre-treatments such as sulphitation often used to minimise quality deficiencies could be avoided. Sulphitation has been recently under critical consideration with respect to allergen labelling of foodstuffs implemented by EU-Member States in November 2004 (Directive 2003/89/EC) [Directive 2003/89/EC. Official Journal of the European Union, 25.11.2003, pp. L308/15–18 (http://europa.eu.int/eur-lex/pri/en/oj/dat/2003/l_308/l_30820031125en00150018.pdf)]. Export quality was improved and the drying process simplified, improving the utilisation of drying capacities. Particularly referring to an application of the technology in small- and medium-sized enterprises with limited investment possibilities, the suggested novel drying procedure in mango processing aimed at the optimisation of well-established simple drying methods instead of choosing technically more sophisticated technologies.     

水杨酸和硝普钠协同处理对芒果贮藏品质及抗氧化活性的影响

为探究水杨酸(salicylic acid,SA)和一氧化氮(nitric oxide,NO)处理在采后芒果果实贮藏品质和抗氧化能力维持中的协同作用,以'台农'芒果为材料,研究经2?mmol/L?SA和0.25?mmol/L?NO供体硝普钠(sodium nitroprusside,SNP)处理后常温贮藏期间果实外观品...     

采后BTH处理及粉红单端孢(Trichothecium roseum)挑战接种对厚皮甜瓜果实苯丙烷代谢活性的诱导

以‘玉金香’甜瓜为试材,用0.1g/LBTH浸泡处理10min,测定BTH处理及T.roseum挑战接种对果实苯丙烷代谢关键酶活性和产物积累的影响。结果表明,BTH处理有效降低了损伤接种T.roseum的病斑直径,提高了果实体内苯丙氨酸解氨酶（PAL）、4-香豆酰-辅酶A连接酶（4CL）的活性,增加了总酚、类黄酮及木质素含量。T.roseum挑战接种可进一步促进上述苯丙烷代谢关键酶活性的提高和产物的积累。由此表明,采后BTH处理可通过诱导厚皮甜瓜果实的苯丙烷代谢来增强果实对采后病害的抗性。      

Reutilization of mango byproducts: study of the effect of extraction solvent and temperature on their antioxidant properties

Mango biowastes, obtained after processing, contain large amounts of compounds with antioxidant activity that can be reused to reduce their environmental impact. The present study evaluates the effect of solvent (methanol, ethanol, acetone, water, methanol:water [1:1], ethanol:water [1:1], and acetone:water [1:1]), and temperature (25, 50, and 75 °C) on the efficiency of the extraction of antioxidants from mango peel and seed. Among the factors optimized, extraction solvent was the most important. The solvents that best obtained extracts with high antioxidant capacity were methanol, methanol:water, ethanol:water, and acetone:water (β-carotene test, antioxidant activity coefficient 173 to 926; thiobarbituric acid reactive substances test, inhibition ratio 15% to 89%; 2,2'-azino-bis-(3-ethylbenzothiazoline)-6-sulfonic acid ABTS(·+); and 2,2-diphenyl-1-picrylhydrazyl DPPH· scavenging, 7 to 22 and 8 to 28 g trolox equivalent antioxidant capacity [TE] per 100 g mango biowaste on a dry matter basis [DW]). Similarly, the flavonoid (0.21 to 1.4 g (+)-catechin equivalents per 100 g DW), tannin (3.8 to 14 g tannic acid equivalents per 100 g DW), and proanthocyanidin (0.23 to 7.8 g leucoanthocyanidin equivalents per 100 g DW) content was highest in the peel extracts obtained with methanol, ethanol:water, or acetone:water and in the seed extracts obtained with methanol or acetone:water. From the perspective of food security, it is advisable to choose ethanol (which also has a notable antioxidant content), ethanol:water, or acetone:water, as they are all solvents that can be used in compliance with good manufacturing practice. In general, increasing temperature improves the capacity of the extracts obtained from mango peel and seed to inhibit lipid peroxidation; however, its effect on the extraction of phytochemical compounds or on the capacity of the extracts to scavenge free radicals was negligible in comparison to that of the solvent. PRACTICAL APPLICATION: There are many antioxidant compounds in mango peel and seed, and they could be used as a natural and very inexpensive alternative to synthetic food additives. However, the conditions in which the antioxidants are extracted must be optimized. This work proves that conditions such as extraction solvent or temperature have a crucial impact on obtaining extracts rich in antioxidants from mango biowastes.     

Resistance of industrial mango peel waste to pectin degradation prior to by‐product drying

Susceptibility of industrial mango peel waste to pectin degradation during storage at ambient conditions (25 °C, 63% relative humidity) for up to 5 h before by‐product stabilisation by drying was explored. Depending on the interim storage period in the wet state, pectins were recovered from the dried peels by hot‐acid extraction. Most important, pectin degradation during the temporary storage of the wet peels was insignificant, as revealed by yields, composition, average molecular properties, and techno‐functional quality. Hardly acetylated (DAc 2.5–4.5%), rapid‐set high‐methoxyl pectins were obtained at starch‐corrected net yields of 14.1–15.6 g hg^?1. Irrelevant de‐esterification during peel storage in the wet state was confirmed by overall uniform setting temperatures. Arabinogalactans, uniformly indicated by high molar galactose/rhamnose ratios of 13.8–16.9 mol/mol and an arabinose percentage of 9.5–14.4 mol hmol^?1 of galactose residues, affected the galacturonide contents, intrinsic viscosities, and gel strengths throughout. The wet peels, derived from widespread manual peeling in mango canning, tolerated intermediate storage for 5 h, thus facilitating by‐product stabilisation on smaller scales.