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Abstract V SUMMARY AND CONClUSION This study was crried out on apricot and guava fruits of Amaar and Balady cultivars, respectively during two successive seasons of 1988 and 1989. Forty five trees from each cultivar grown in two orchards located at two regions within Kalubia governorate, namely El-Seiafa-Toukh and Nawa-Shebein El-Kanater were devoted for apricot and guava, respectively, with a main purpose for studying the following: V .1.- Apricot: V.1.1- Determination of maturity indices: The periodical changes in both fruit physical and chemical characteristics were studied through the last stage of fruit development, since fresh weight, dimensions, shape index, flesh firmmess, rind colour, TSS%, acidity%, Tss/acid ratio and sugars content of fruit were included in this respect. ”I • --- _.-- -- .._-------- ---------- -- .--_._------- V.1.3- Effect of some prestorage trea ents on fruit keeping quality:” Soaking for 2-3 minutes either in warm water (4s0e) or in solution of borax + boric acid mixture at concentration of 4,2% respectively, bes’de washing with tap water as control were investiga under three different condition of storage ambient ”room codition of 270C ±. 2 and 55-65% RH” cold storage either at SaC or ooe, with 80-90% Fresh weight loss%, decay% (discarded fruits%), fIe h fruit firmnss, TSS%, acidity%, TSS/acid ratio and content of apricot fruits were periodically dete in relation to the above mentioned storage treatme V.l.2- Effect of transporting container damage of apricot fruits: Palm crate with cardboard liner (1 box (15 kg.), plastic box (10 kg.), (4 kg.)were examined {161} on mechanical kg.), plastic carton box of -- --- ._.------- _.-._.---_.-- .-.-------- V.2- V.2.1- Guava: Effect of kind of transportinq containers on fruit damages of guava: Four types of containers were included i. e ., palm cra~e with liner (15 kg.), plastic box (25 kg.) plastic box (20 kg.) and car~on box of about 5 kg capacity. V.2.2- Effect of pre-storage treatments on keepinq quality of guava: Four pre-storage treatments, namely: 1- Washing with water (control), 2-soaking in warm water (45°C), 3-soaking in solution of borax + boric acid mixture at” 4,2t concentration, respectively and 4-oi1 paraffination were investigated. Since, periodical changes of the above men~ioned characteristics previously studied with apricot fruits were also concerned for Ba1ady guava under three conditions of storage i.e. , room temperature t122°e± 2 and RH 50-60’’’, cold storage either at 15°C or 1oOe with RH of 80-90t during both 1988 and 1989 seasons. The obtained results of the present investigation could be summarized as fOllows: _. -_.-_ .. _._.~---~------- ----------- V.l. Apricot: V.l.1- Changes in physochemical properties leading to maturity of developing Amaar apricot fruits: V.l.1.a- Fruit fresh weight: Fresh weight of Amaar apricot fruit was gradually increased-at an equal intermediate rate from April 23th or 18th till May 13th and 3rd during 1988 and 1989 seasons, respectively, where the rate was suddenly increased to show its maximum _level. Thereafter the increase was acutely reduced, then nearly ceased on May 18th and 8ib when the average weight reached 16.7 and 15.6qm during both 1988 and 1989 seasons, respectively. V.l.1.b- fruit dimensions: Obtained data revealed clearly that the previously mentioned trend of the fruit fresh weight was similar to that detected with both fruit dimensions i.e., fruit length and diameter, however the rate of fruit diameter showed a slight increase over that of length. V.l.1.C- fruit shape index: However no statistical differences were inauced regarding fruit shape index (fruit length: fruitdiameter), but a very little reduce in its value was ----------- --------._--------------------- observed which is the main responsible for the tendency of Amaar apricot fruit to take the relative rounded shape instead of the oblonged one that reflects the relative higher rate of diameter increment then fruit length. V.1.1.d- fruit flesh firmness: Obtained results declared that fruit firmness of Amaar apricot cv. was continuously decreased with the age progression, however the rate of fruit softness resulted during the first measuring dates was obviously greater, then reduced acutely on May 3rd and April 28th for both III and 2nd seasons, respecti vely till the last measuring date where the decrease in fruit firmness was significantly neglected. V.1.1.e- Rind colour: Data obtained showed that the rind ground colour was gradually changed from deep green ”S.G S/8 strong green It to a variable degrees of the yellowish green colour from one season to another. Thus, it could not be recommended to depend on the fruit skin colour only for determining the suitable picking stage. .’ ---,--,~ --- ”-------------- -------,-,----’~ V.l.l.f- fruit juice total soluble solids%: Data obtianed disclosed clearly the occurrence of a significant gradual increase in fruit juice TSS% by aging, however the rate was sharply increased during the second third of measuring dabes, V.l.l.g- fruit juice total acidity: The present results showed that fruit juice total acidity% was gradually decreased with the advancement of fruit age. Such decrease took place at steady mOderate rate through the whole period of the last developing phase, which reflects a relative lower variance and consequently changes in fruit juice acidity of Amaar apricot fruits is not enough to be used alone as an maturity index. V.l.l.h- fruit juice TSS/Acid ratio: Data obtained during both seasons, revealed clearly that TSS/acid ratio in fruit juice of Amaar apricot cv. Was continuously increased by fruit aging till it reached 4.5-4.7 at maturity. Generally it could be recommended that Amaar apricot fruit could be safely picked at Toukh ”Kalubia --_ ...._- ..__ ._---_ .._---- ---._._--_ ... governoratelt depending upon the following. characteristics as maturity indices: 1- Fruit fresh weight of about 16.0 gm. 2- Fruit dimensions of 3.0 and 3.3 cm. for diameter and length, respectively. 3- Flesh firmness of about 9-10 lb/inch2 4- TSS% of about 10 5- TSS/acid ratio of about 4.5 V.1.2- Effect of transporting containers on mechanical damageof Amaarapricot fruits: Data obtained regarding mechanical damage.in Amaar apricot fruit as influenced by type of transporting containers ”padded bottom palm crate with perforated carton liner 15 kg cap., plastic boxes of 15 and 10 kg.cap. and carton box of 4 kg.cap. tI showed clearly that four forms of damages namely bruises, abrasions, punches and scratches were occurred at destination. However, palm crate with carton liner ”15 kg.cap.” resul ted in the highest value of the total damaged frui ts percentage followed by plastic boxes of 15 and 10 kg. capacity , as well as carton box of 4 kg.cap. showed the lowest percentage. On the other hand bruises represented the main f or. of mechanical damage, but the reverse was true for punches., Meanwhile, damaged fruits% due to the incidence of either abrasions or scratches were in between, however occurrence of the former from was more pronounced. Generally it could be concluded that both plastic boxes of 10 kg. and carton boxes of 4 kg.cap. were the most suitable types of transporting containers for apricot fruits, especially the second one . . V.1.3- Effect of some prestorage treatments on keeping quality of stored Amaar apricot fruits: In this regard Amaar apricot fruits were stored under three different condiions ”room temperature, refrigerated storage at SaC and oOe with 80-90% RH” after they had received th following prestorage treatments: 1- washing with tap water ”control”, 2- soaking for 2-3 minutes either in hot water t14Soe” or solution of borax + boric acid mixture at 4,2% concentrations, respectively. Data obtained concerning the periodical response of some fruit physical and chemical properties to the different treatments during the whole duration of storage could be summariezed as follows: ...__.. - ..._.- .._.~- ---------------- ----_._.- .~-. (168) V.1.3.1- Periodical loss% in fresh weight: from the obtained results, it could be noticed that Amaar apricot fruits showed obviously”a continuous reduction in their fresh weight during storage regardless of storage conditions or prestorage treatments. However the rate of reduction per an interval was more greater in these fruits remained under room condition than those kept up under cold storage. In addition, soaking Amaar apricot fruits either in hot water ”4SoC” or in solution of borax + boric acid mixture showed a beneficial effect on reducing the rate of fresh weight loss , in cold stored fruits, however, such trend was more pronounced at OoC Meanwhile, this trend was true with hot water only for fruits under room condition, but with soaking in solution of borax + boric acid mixture the reverse was true. V.1.3.2- Percentage of periodical decayed fruits: Data obtained showed that the incidence of decay in Amaar apricot fruits stored under room condition had been taken place too earlier ”2 days froll starting storage”. However, not only no sign of decay could be observed during the first two sorting dates of cold -----” - ------- stored fruits but also 15 days in most cases are needed to pass before the occurrence of decay. Moreover, the rate of discarding ”both decayed and shrivelled fruits” was continuously increased as the storage period was prolonged, where the last sorting date pointed out the maximum value of discard~ed%, regardess of storage condition or prestorage treatment. On the other hand, the average rate of discarded fruits under cold storage per an interval was greatly reduced to represent only about 10% of that detected under ambient condition. In addition, prestorage soaking either in hot water 45°C or in borax + boric acid mixture 4,2%, generally reduced the discarding% of Amaar apricot fruit, e.,PFially those stored under SoC and 80-90% RH where differences were significant as compared to control. V.1.3.3- Periodical changes in fruit firmness: Data obtained revealed that flesh firmness of Amaar apricot fruits wert gradually decreased as duration of storage was extended. However, the rate of softness was more greater under ambient storage than cold storage. On the other hand rate of decrease in flesh fruit firmness was sharply increased during the last third of storage duration, either at room or cold _. -- _..•~ - ._--_ ... -- .._-------------~ - - -~--_ .. _._----- yVt. storage. In addition, hower”.no specific trend could be detected as the effect of prestorage treatments was concerned, but to some extent it could be concluded that control and soaking in borax + boric acid mixture were of a compareable influence from one side and resulted in a relative firmner fruits than hot water treatment from the other side as an average of 2 seasons was regarded. V.1.3.4- Periodical changes in TSS%: Fruit juice TSS% of Amaar ”apricot cv. was gradually increased by the advancement of storage period. However, such increase was significant, regardless of prestorage treatment and condition of storage, but soaking fruits in hot water u45°C” exceeded statistically two other treatments during both seasons as an average of values determined throughout the whole period of storage was concerned. V.1.3.S- Changes in fruit juice total acidity: Periodical determination of total acidity’ of Amaar apricot fruits during storage revealed the incidence of a gradual decrease with storage extention. Soaking fruits in hot water ”45°C” showed generally the -_. -----_ .. - -- -_.”_ .. ------ (171) lowest value of fruit juice total acidity, however such trend was more pronounced with cold stored fruits at SoC where the differences were significant as compared either to those of control or borax + boric acid soaking treatments during both seasons of study. V.1.3~6- Changesin ~ruit juice TSS/acid ratio: It could be noticed clearly that a steady gradual increase in the TSS/acid ratio of apricot fruits was occurred with the advancement of duration of storage. On the other hand, prestorage treated fruits by soaking in hot water showed always the highest value of fruit juice TSS/acid ratio. V.1.3.7- Changes in ~ruit juice total sugars percentage: It could be noticed clearly that fruit juice total sugars% continuously increased as the storage time was advnaced for fruits stored either under room condition or refrigerated storage O°C/SoC. However, such increase was more pronounced in hot water soaked fruits, expecially when storage was carried out under ambient condition. on the contrary, fruit juice total sugars’ - .__ .. ---- ._.- - -_.-_. ------------_. (172) of Amaar apricot fruits at the last determining date tended to decrease and took other way around. V.2- Guava: V.2.1- Effect of transporting containers on mechanical damage of Balady quava fruits: Data obtained pointed out the superiority of ca rton boxes of 5 kg. capacity in reducing the percentage of total damaged fruits than other types of transporting containers, followed by plastic boxes of 20 kg capacity, plastic boxes of 25 kg cap. and palm crate with carton liner which ranked last, in this regard. Moreover, three forms of mechanical damages were observed, where bruises was the major one, while abrasions and punches were equally exhibited and both together represented less than 10% of the total damaged fruits, regardless of type of transporting containers. Meanwhile, no scratches had been occurred at destination. V.2.2- Effect of some postharvest treatments on storage ability of Balady guava fruits: Four post-harvest treatments namely: 1- Washing in tap water ”control”, 2- soaking in hot water ”45GC”, 3- soaking in solution of borax + boric acid mixture ”4,2%” and 4- paraffination had been applied before storing guava fruits under room condition ”temp of 22°C + 2 and SO-60% RH” and refrigerated storage ”temp at 1SOC/10°C with 80-90% RH”. Data obtained concerning periodical changes in both fruit physical and chemical properties in relation to the different prestorage treatments throughout storage under its three different conditions could be summarized as follows: V.2.2.1- Periodical 1055% in ~resh weight: stored fruits of Balady guava showed a continuous loss in their fresh weight with the advancement of storage period, however loss rate was relatively higher in fruits kept up under ambient temperature than those of refrigerated storage. On the other hand surface coated fruits with paraffinic oil showed significantly the lowest value of 1055%, while two other treatments i.e., soaking either in hot water or borax + boric acid mixture slightly reduced the loss rate than control. V.2.2.2- Decay percentage: Data obtained pointed out that condition of storage had a striking effect on decay% in Balady guava -- --- -------- fruits during storage, where no sign of decay could be observed before 2 or 3 weeks from starting storage for the prestorage treated fruits by soaking/surface coat1.ng treatmentsII as kept up at 15°C and 10°C, • respectively . However, under room condition one week only was needed to pass for the incidence of decay in most cases. Moreover, paraffination treatment was the superior where it showed not only the lowest percentage of discarded fruits, but also it delayed statistically the occurrence of decay than other treatments. Moreover,· soaking in borax + boric acid mixture was also effective, especially under cold storage. V.2.2.3- Fruit firmness: The present result showed that fruit flesh firmness of Balady guava fruits was continuously decreased with extention of storage time. However, fruit softening took place sharply under room condition, but at refrigerated storage it was gentely continued, especially with 10°C stored fruits. On the other hand the response to the prestorage treatments was significant, where the paraffinic oil surface coated fruits showed statistically a great retardation of the quic~decline in their flesh firmnes than those of other treatments since the hardest flesh at any sorting date was always concomitant to such fruits. Moreover, soaking either in hot water or solution of borax + boric acid mixture helped in rema-ning fruits more firmer than control, especially for cold stored fruits of Balady guava cv. V.2.2.4- Fruit juice TSS%: Data obtained declared that fruit increased continuously as duration of extended until the last date where the juice TSS% storage was increase was ceased or the response took other way around. However, the rate of increase was relati vely higher in that fruits held under room condition. Meanwhile, paraffination treatment resulted statistically in the lowest rate of increase as compared to control or two other treatments. The reverse was true with hot water It 45°C” treatments but the increase was not significant as comparedto control. V.2.2.S- Fruit juice total acidity%: The present result showed that fruit juice total acidi ty percentage of Balady guava frui ts was significantly decreased with the advancementof storage time. The rate of decrease was more pronounced in frui ts stored under room condi tion than those under refrigerated storage. On the other hand, all the prestorage treatments were appreciably of the same effect from one side and did not statistically differ than control from other in this respect. V.2.2.6- Fruit juice TSS/acid ratio: The value of fruit juice TSS/acid ratio was continuously increased by the advancement oFstorage duration, regardless of both condition of storage and prestorage treatments applied. However, the rate of increase was obviously reduced under cold storage 1SOC!1aOc. However, the ratio was responded to the prestorage treatments, but it was less pronounced than that detected to extending storage time. In addition, the lowest value of TSS!acid ratio was always concomitant to the surface coated guava fruits with paraffinic oil followed by (B+8) , but the reverse was true with fruits of both hot water and control treatments. ,----- V.2.2.7- Fruit juice total sugars percentage: As for the periodical changes in fruit juice total sugars’ in guava fruits through duration of storage, it could be noticed that a gradual increase was obviously detected by prolonging time, except at the last date, where the increase was not only ceased but also the trend took other way around in most cases. Such trend was true regardless of condition of storage or prestorage treatments, however the rate of increase under refrigerated storage was lesser than that of ambient stored fruits. On the other hand surface coated fruits with paraffinic oil showed generally lower sugars’ than those other treatments especially in cold stored fruits where the differences were significant. The reverse was true with hot water soaked fruits however differences were insignificant in most cases, as well as soaked fruits in borax + boric acid solution and those of control were in between. |