Physiological Studies On Mango Fruits Handling:

Somia Ahmed Abdel Baset Fawaaz

This study was carried out on mango fruits of Alphonse cultvar, during twosuccessive seasons of 1996 and 1997. Twenty seven fruitful” frees •of about 20 year old weredevoted for this study during both seasons. The abovementioned selected trees were grownin the farm of Horticultural Research Instute, El-Kanater, Kalubia Governorate, Egypt, witha main purpose for studying the following:-V-I-Determination of maturity indices:-The main purpose was aimed to establish fruit maturity indices of Alphonse mangocv. by which the suitable picking stage of such perishable fruits’ could be easily determined.Consequently the periodical changes in both fruit physical and chemical characteristicswere studied through the last stage of fruit development, since fresh weight, dimensions,shape. index , flesh firmness, texture, specific gravity, rind color, TSS%, total acidity %,TSS lacid ratio, ascorbic ,acid content, total sugars and total carotenoids content offruitwere included in this respect.V-2-Effect of some prestorage treatments on fruit keeping quality:-I. Soaking fruit for 2-3 minutes either in hot water (45°C).2. Soaking fruit in borax solution at 6%.3. Soaking fruitin vapor-Gard at 2%.4. Washing fruit with tap water as control.were investigated under different conditions of storage as follows:-V-2-1- Ambient condition (room temperature of 27°C :!: 2 and 55-65 % R.H.)V-2-2- Cold storage either at 8°C, 10°C, BOC or intermittent system with 80-90%R.H. •Fresh weight loss %, decay % (discarded fruits %), flesh fruit firmness, fruit texture,fruit colour, T~S %, acidity %, TSS/acid ratio, ascorbic acid content, total Sugars, andtotal carotenoids content of Alphonse mango fruits were periodically determined inrelation to the above mentioned storage treatments. The’ obtained results of the present investigation could be summarized as follows;-#V-I-Changes in physochemical properties leading to maturity of developing Alphonsemango fruits:1. Fruit fresh weight:-Alphonse mango fruit was gradually increased significantly till reached its maximum valueat maturity stage after 135 days from full bloom during both 1996 and 1997 seasons.2. Fruit dimensions:-obtained data revealed clearly that the previously mentioned trend of the fruit fresh weightwas similar to that detected with both fruit dimensions i.e., length and diameter, each wasincreased gradually and significant and reached its maximum value at maturity stage after135 days from full bloom during both seasons of study3. Fruit shape index:-However, no statistical difference were induced regarding fruit shape index (fruit length:fruit diameter) after 135 days from full bloom, but a very little reduce in its value wereobserved.4-Fruit flesh firmness:Obtained results declared that fruit flesh firmness of Alphonse mango cv. was graduallydecreased and significantly as the season was advanced till reaching its minimum value at--_._ .._--~_._._-_._---- ....maturity stage i.e, after 135 days from full bloom. At maturity stage it become 19.6 and19.13 Ib/inch2 for the 1996 and 1997 seasons, respectively.S-Fruit texture:IWith respect to the periodical changes in Alphonse mango fruits texture, it is obvious thatit was gradually decreased and significantly by advancement of fruit age till reachedmaturity stage during the study6-Fruit specific gravity:-Specific gravity was increased gradually and significantly to reach its maximum value atmaturity stage, specific gravity for Alphonse mango fruits reached 1.51 and 1.62for 1996and 1997 seasons, respfctively.7-Fruit colour:The peel colour as radually changed from the very dark green” 7.50 2/4” after 105-~’-.~ - -. - -days to strong green colour ”7.504/4 or 4/6tt at 135 days from full bloom. Moreover, pulpecolour was changed from light yellow 5Y 8.12 or 8.5/4” to yellow 5Y 8.5/8 during the twoseasons of study.8-chemical properties:-Data obtained increased gradually and significant by increase in fruit juice TSS %,TSS/acid ratio, ascorbic acid content, total sugars and carotenoids content and decreasetotal acidity by fruit aging till maturity stage during both seasons of study.IV-2-Effect of some prestorage treatments on keeping quality of Alphonsemango fruits under different conditions of storage:IV-2-I- Effect of some prestorage treatments on keeping quality of Alphons Mangofruits under ambient temperature.I. In this regard Alphonse mango fruits were stored under room temperature, after theyhad received one of the following prestdrage treatments: a - Washing with tap water”control”; b- Soaking for 2-3 minutes either in hot water ”45°C” or solution of borax at6% concentration and c- Immersions in vapor Gard solution at 2%.Data obfaified”collI::eiriiiIg the periodical response of some fruit physical andchemical proprieties to the different treatments during the Wholeduration of storage couldbe summarized as follows:-II V-2-I-I- Effect on fruit physical characteristics:-1. Concerning the specific effect of prestorage treatments on physical characteristics,obtained results, revealed that immersion of Alphonse mango fruits in a vapor Oradsolution showed the lowest value in weight loss % followed by dipping in boraxsolution, and dipping in hot water, while, washing in tap water ranked last in thisrespect. In addition, the specific effect of prcstorage treatments on both fruit firmnessand fruit colour took the other way around during both seasons of study.2. With respect to the specific effect of storage period on physical charactcristics, fromI#-the obtained data, it could be noticed that Alphonse mango fruits showed obviously acontinuous reduction in their fresh weight with extending storage duration. In addition,both fruit firmness and fruit texture took the other way around during both seasons ofstudy.3. A significant effect was detected as a result of the interaction between prestoragetreatments and storage periods, where Alphonse mango fruits treated with vapor Gardsolution and stored for 9 days under room condition had the lowest value in freshweight loss %and exhibited the highest values of both fruit firmness and fruit texture ascompared with control during the two seasons of study.4. Data obtained showed that, the peel ground colour was generally changed from darkgreen colour to light green colour after 6 days from storage, then it changed to strongyellow colour after 9 days in both hot water and control treatments. In addition, fruitstreated with both borax and vapor Gard changed from dark green colour to green yellowcolour after 6 days from storage followed by changed to yellow colour after 9 daysfrom storage during 1996 and 1997 seasons.IV-2-1-2- Effect on fruit chemical characteristics:-I. Regarding the specific effect of prestorage treatments on fruit chemicalcharacteristics, data obtained displayed that immersion of Alphonse mango fruits invapor Gard solution resulted in the lowest values of TSS%, ascorbic acid content, totalsugars and fruit carotenoids content followed borax solution. In addition no significanteffect couldoeof)serVedirifrilitjuice total acidity during both seasons of study.2. Concerning the specific effect of storage periods, the obtained data declared that asignificant increase was detected on fruit juice TSS%, ascorbic acid, total and sugarsand carotenoids content continuously as duration of storage was extended until the end Iof storage while total acidity took the other way arround during 1996 and 1997 seasons.3. The obtained data showed that a significant interaction was found betweenprestorage treatments and storage periods, where, Alphonse mango fruits treated witheither borax’ or vapor Gard solutions and stored at 9 days under room condition had thelowest values of fruit juice TSS%, acidity% ascorbic acid content, total sugars andcaroteonids contents as compared with other treatments during both seasons.•IV-3- Effect of s«»Uedifferent temperatures of cold storage treatments onkeeping quality of Alphonse m,ango fruits:-IV-3-t- Effect on fruit physical characteristics:-1- Regarding the specific effect of different temperature of cold storage treatments onphysical characteristics, it is quite evident that, stored Alphonse mango - fruits at thetemperature of 13°C showed the highest values of weight loss % and discarded fruits. percentage followed in a decreasing order by storage at IODC and SoC. On the otherhand stored fruits at intermitent treatment had the lowest value in this respect. On theother hand, both fruit firmness and fruit texture took the other way around during thestudy.2- Concerning the specific effect of storage periods -o-n physical characteristics, data - ~._-obtained showed clearly that both loss in fresh weight% and discarded fruit percentagetook place continuously as storage period was extended during both seasons of study.In addition, both fruit firmness and fruit texture were decreased with the extension ofstorage time to reach its minimum values at the end of storage period (40 days) duringthe two seasons of study.3- A significant response to the interaction effect between the different cold storagetemperatures and time of storage, was found. However, refrigerated storage under13°C for 40 day, showed the highest value of weight loss % and discarded fruitpercentage while fruit firmness and fruits texture had the lowest alue n his oncernduring the two-seasons of study. In addition, refrigerated storage under intermittent -----_.~-_.._---_. - ---treatment for 40 days had the lowest value of weight loss % and discarded fruitpercentage as compared with other treatments but response of both fruit firmness andfruit texture took the other way around during 1996 and 1997 seasons.4- Concerning the periodical changes in fruit colour of Alphonse mango fruits datashowed that the peel fruit was colour changed from dark green to light yellow underintermitent system after 40 days from storage, while fruits stored at goC changed tolight green after 20 days, from storage then changed to light yellow after 30 daysfollowed by strong yellow after 40 days from storage.As for the fruit pulp colour, it was changed under intermittent treatement from lightyellow to yellow colour after 20 days from storage followed by strong yellow colour after30 days from storage, then changed to orange yellow colour after 40 days. In addition,pulpe fruit colour w». changed light yellow to strong yellow colour after 30 days thenchanged to orange yellow colour after 40 days from storage.•V-3-2- Effect on fruit chemical characteristics:-1- Concerning the specific effect of different temperatureso(cold storage on chemicalcharacteristics, it could be observed generally that the values ofTSS %, TSS/acid ratio,total sugars and carotenoid contents increased with increasing storage temperaturewhile total acidity, and ascorbic acid contents took the other way around in this respectduring the two seasons of study.2- Regarding the specific effect of storage periods, it could be shown that a gradual _increase in TSS %, TSS/ acid ratio, ascorbic acid content, total sugars and totalcarotenoids were obviously occurred as the storage duration was advanced while totalacidity took the other way around during 1996 and 1997 seasoris~•3- A significant interaction between different temperatures of cold storage and storageperiods was shown. However, Alphonse mango fruits stored under l3°C for 40 daysexhibited the higher values of TSS%, and TSS% / acid ratio during the two seasons ofstudy. Moreover, stored mango fruits under intermitent treatment for 40 days had thehighest value of ascorbic acid content, total sugars and total carotenoids content duringI996 and 1997 seasons.4- While respect to shelf life of Alphonse mango fruits as influenced by cold storagetemperature, it could by safely concluded that stored fruits under intermittent systemshowed more ability for 4 days of shelf life followed in a decreasing order by thosestored underlr”C”;T!foCandT3°C during both 1996 and 1997 seasones.IV-4- Effect of some prestorage treatments on keeping quality ofAlphonse mango fruit under different temperature of cold storage:-1V-4-1- Effect on fruit physical characteristics:-1- Concerning the specific effect of different cold storage temperatures on fruit physicalcharacteristics, results indicated a significant increase -in fresh weight loss % andpercentage of discarded fruits with increasing the temperature of cold storage in both1996 and I 997 seasons. On the other hand, Ap1honse mango fruits had the lowest valueof both fruit firmness and fruit texture under the highest temperature of cold storageduring both seasons.2- With respect to the specific effect of storage periods on fresh weight loss %anddiscarded fruit %data obtained showed a significant increase with extension of storagetime while the response of both fruit firmness and fruit texture took the other wayaround during the two seasons of study.3- Regarding the specific effect of prestorage treatments, on fresh weight loss %anddiscarded fruits-%;-the• obtained data showed that the vapor Gard treatment decreasedsignificantly fresh weight loss % and discarded fruits % followed in a increasing orderby Borax treatment, hot water treatment, and control treatments in this respect,respectively. Moreover, vapor Gard treatment significantly increased both fruit firmnessand fri.it texture followed in a decreasing order by borax; hot water, and controltreatments in this respect during both seasons of study.4- A markable interaction was shown between different temperatures of cold storage,storage periods and prestorage treatment. Meanwhile, immersion of Alphonse mangofruits in vapor Card solution and stored under s-c for 40 days had the lowest value offresh weight loss % and discarded fruit %as well as showed the highest value of bothfruit firmness and fruit texture during 1996 and 1997 seasons. On the other hand,control treatment took the other way around in this respect.5- Concerning the juit colour of Alphonse mango fruits, it is quite evident that, seasonalchanges in fruit peel colour take place through different storage whereas it changedfrom dark ,green colour to yellow colour., Also., fruit pulp colour passed throughdifferent sh,ades from light yellow colour to orange yellow colour at the end of storagebut these shade differed from treatment to anotherduring the study.Iv-4-2- Effect on fruit chemical characteristics:-1- -Rcgarding the specific effect of different temperatures of cold storage on chemical”characteristics showed that TSS%, TSS/acid ratio, ascorbic acid content, total sugarsand carotenoids contents increased with increasing storage -temperature, where storedmango fruits at 13°C had the highest values followed in descending order by those at10°C and goC. In addition, response of the total acidit~ took the other way arroundduring both seasons of study.2- With respect to the specific effect of storage periods, it could be showed that asignificant increase was found in TSS%, TSS/acid ratio, ascorbic acid content, totalsugars and carotenoids contents. were obviously occurred as a storage duration wasadvanced while total acidity took the other way around during the two seasons of study.3- Regarding the specific effect of prestorage treatments, the obtained data revealed thatdipping Alphonse mango fruits in vapor Gard solution had the lowest values of TSS%,TSS/acid ratio, ascorbic acid content, total sugars and total carotenoids contentfollowed in an increasing order by borax prestorage treatment followed by hot waterprestorage treatment while control treatment had the highest values in this respect--- ...- _._.,-- ._.. -during 1996 and 1997 seasons; In addition fruit juice total acidity took the other wayaround.4- A considerable interaction between different temperature of cold storage, storageperiods. , and prestorage treatments was found. In this respect, immersion mango fruits invapor Gard solution and stored under s-c for 40 days had lowest values of fruit loss %,discarded fruit %, TSS/acid ratio and carotenoids content while total acidity ’showed thehighest value during both seasons of study. In addition both total sugars and totalascorbic acid content showed no definit trend during 1996 and 1997 seasons.5- Fruits of all treatments that reached the end of storage period in a good physicalcondition were able to maintain their marketing ability for 4 days after storage exceptcontrol and hot water treated fruits stored at 13°C as they showed no shelf life ability. Inaddition, Alphonse mango fruits could be stored for longer periods, by immersion eithervapor Gard or ’-rax solution and storage under goC these treatments increasing itsability to be successful in marketing.Generally, it could be safely concluded from the.present. work that the followingbases and procedures must be taken into considuration and recommended lor a safetystorage and marketing of such perishable fruits” Alphonse mango fruits” under the samecondition of EI• Kanater, Kalubia, Governorate.a. First fruit harvesting must be done at markting ”135 day from full bloom”, fruit pulpcolur became light yellow and fruit flcsh firmness became 19.13 and 19.60 lb/inch’,b- Immersion in borax or Vapor-Gaurd preceding 9 days ambient storage for localmarkting.c- Immersion in borax or Vapor-Gaurd befor refrigerated storage at 8 °C & 90% R. H. forday with the exporting purpose.