M.Y. Rohani and M.A. Siti Halijah - PDF document

M.Y. Rohani and M.A. Siti HalijahJ. Tro
M.Y. Rohani and M.A. Siti HalijahJ. Trop. Agric. and Fd. Sc. 34(2)(2006): 257Ð268Physico-chemical changes during ripening of ciku at differentM.Y. Rohani* and M.A. Siti Halijah**Key words: ripening, maturity stages, fruit quality, cikuThe maturity stage of ciku var. Subang at harvest influenced the flavour, tasteand consumer acceptability of the fruit. Fruit harvested at 6.5Ð7 months aftercontained lower total soluble solids (12Ð15% Brix) and total sugars (7Ð10%).Fruit harvested at these stages (6.5Ð7 months after flower opening) were highlyunacceptable. The best stage to harvest the fruit was at 7.5Ð8 months after floweropening. At this stage the fruit ripened properly within 4Ð6 days and theclimacteric peak also occurred at the same time. The flesh colour changed to17Ð19% Brix and 12Ð15% respectively with pH 5Ð5.6. The proper developmentand taste. Fruit harvested at these stages (7.5Ð8 months after flower opening)*Food Technology Research Centre, MARDI Headquarters, Serdang, P.O. Box 12301, 50774 Kuala Lumpur, Malaysia**Technical Services Centre, MARDI Headquarters, Serdang

, P.O. Box 12301, 50774 Kuala Lumpur, Ma
, P.O. Box 12301, 50774 Kuala Lumpur, MalaysiaAuthorsÕ full names: Rohani Md. Yon and Siti Halijah Md. Ali©Malaysian Agricultural Research and Development Institute 2006IntroductionIn the Third National Agriculture Policy L.) is one ofindustry in Malaysia (Anon. 1998). Thecultivation. This cultivar is well received bygritty texture (Raziah et al. 1991). The fruitmatures 7Ð9 months after flower opening(Siti Halijah and Tham 1996). However, it isdifficult to determine the correct maturitymature fruit cannot be clearly differentiatedwhen the age is between 6.5Ð9 months afterflower opening. At this age the size of thelatex flow are also not very effective.is important because it affects the flavour,aroma and storage quality, whichcollectively affects the commercial value ofpoor storage quality. The ability of the fruitmaturity. Therefore, the main objective ofduring ripening. The physiologicalbe monitored. These changes greatlyCiku var. Subang was obtained from a farmin Kundang, Selangor. To obtain fruits atdifferent maturity stages, tagging was doneat flower opening. The fruits

were tagged atopening. The harvested fr
were tagged atopening. The harvested fruits were broughtto the Food Technology Research Centreused in the experiment. They were thenremove the bloom and brown scales. At eachTo determine the respiration rate and16fruits were taken at each harvest. Half ofnot induced. All fruits were put intosame temperature. Two fruits, which formedfruit per hour. Respiration rate and ethylene given off by the fruit. The gasinjecting it into a Varian 1420 thermalwith Porapak R of size 80Ð100 mesh. The30ml/min with 30 concentration measured and the gasusing the Varian 1440 flame ionizationPorapak T column of 100Ð120 mesh size.To determine the physico-chemical changesripened at 6 days after induction. Toinduction. The remaining 20 fruits were24h. From the induced fruits, 10 wereM.Y. Rohani and M.A. Siti Halijahin flesh colour, texture, moisture content,red-green axis and b* the yellow-blue. Theof the colour, was also calculated using the + b*by the puncture test using the Instron 1140machine. A puncture was made on theequatorial region of each fruit with a 11-mmMagness Taylor probe using load

cells ofrespectively. The machine was o
cells ofrespectively. The machine was operated withmm/min respectively. The force (kg/mmthe air-oven method (AOAC 1984). Each10Ð15 g of the blended sample was takenuntil a constant weight was obtained. Theloss by the sample. Two samples were takenmodel SA520. The TSS of the fruit juicewas measured using an Atago digitalrefractometer (0Ð32% Brix). Total sugarsTo have an indication of the overallethylene. After ripening the skin wasacceptability. The scores for sweetness werevery poor, 3 = slightly poor, 5 = good and7= very good. The scores for acceptabilitythe different ripening stages. Assumingethylene evolution of ciku var. Subangduring ripening differed at different maturity(Figure 1)respiratory climacteric or an upsurge inethylene production was observed. This wasstill in the preclimacteric growth stage. Atthis stage the fruit was still able to enlarge(Siti Halijah and Tham 1996). Since thereclimacteric fruit (Wills et al. 1989), cikufruits harvested at this stage undergoRespiratory climacteric and upsurge inflower opening. At 7 months theother harvesting stages. The resp

iratory(Figure 1a) with no distinctupsur
iratory(Figure 1a) with no distinctupsurge in ethylene production (Figure 1b)climacteric occurred earlier. Fruit harvested6days after harvesting while those harvested(Figure 1a). The upsurge insame time i.e. within 4Ð6 days (Figure 1b)ethylene. There was a 5-fold increase in6.5months (Figure 2a) but no distinctclimacteric peak was observed. At this(Figure 1a)(Figure 2a)0102060














8.5 monthsml CO2/kg/hl C2H4/kg/h8 months7.5 months7 months6.5 months87654321016Figure 1. Respiration rate (a) and ethylene production (b) of ciku var. Subang during naturalripening at different maturity stages for 8 days at 20 Figure 2. Respiration rate (a) and ethylene production (b) of ciku var. Subang afterinduction with 5 ppm exogenous ethylene at different maturity stages for 8 days at 20 0102070












8.5 months8 months7.5 months7 months6.5 months87654321ml CO2/kg/hDays(a)02461012











87654321l C2H4/kg/hM.Y. Rohani and M.A. Siti HalijahTreating the younger fruit with ethylene alsoforming enzyme

(Abeles et al. 1992). This(Figure 2b)up
(Abeles et al. 1992). This(Figure 2b)upsurge in ethylene production at least a dayethylene. This phenomenon was also4days for fruits harvested at 7.5 months and(Figure 2a)attributes which affect the fruit qualityTham 1996). These include changes incolour, size, weight, texture, total solubleacidity.(Figure 3). The decrease in theincreased. The increase in the a* and b*5055606585





6 days (At ripening)L* valuesb* valuesa* valuesC* values1 day (24 h after induction)0 day (Before induction)8.587.5 76.5-501015




8.587.5 76.51517272931





6 (At ripening)Months after flower openingMonths after flower opening1 (24 h after induction)0 (Before induction)8.587.5 76.51517272931




8.587.5 76.5Figure 3. Changes in flesh colour (L*, a*, b*, C* values) of ciku var. Subang at differentduring maturation. These changes were(Figure 3).(Figure 4)brown. Again, this was indicated by the(Figure4). This can be clearly seen as theinduction. However, after ripening therewere no significant differences in the colour(Figure 3)(Figure5). Howe

ver, when the fruits were(Figure 6)toget
ver, when the fruits were(Figure 6)together (Wills et al. 1989).softening of ciku var. Subang differed atdifferent maturity stages (Figure 6)was probably due to the different rate offruit softening (Wills et al. 1989). Fruitsharvested at all stages of maturity undergo(Figure 6). The ripened fruits wereFigure 4. Rate of change in flesh colour ( L*, a*, b*, C* values) of ciku var. Subang during ripening(after induction with 5 ppm ethylene) at different maturity stagesL* values8.5 months8 months7.5 months7 months6.5 months024602460240246M.Y. Rohani and M.A. Siti Halijah0.000.050.100.150.35Texture (kg/mmTexture (kg/mm6.50.000.05Figure 5. Changes in texture (kg/mm) of ciku var. Subang at different maturity stagesfirmer when harvested at 7.5months after(Figure 5). At this stage a was required to(Figure 7). The decreasingSitiHalijah and Tham 1996). About 3(Figure 8)greatly affect the flavour and taste of theand acceptability. Taste scores indicated that(Figure 9). At these stages ofFigure 6. Rate of change in texture (kg/mm) of ciku var. Subang during ripening (after indu

ction with5 ppm ethylene) at different m
ction with5 ppm ethylene) at different maturity stages0246Texture (kg/mmTexture (kg/mmDays after inductionExperiment 1Experiment 2(Figure 9)(Figure 9).(Figure 10) but(Figure 11). The greatestamount of reduction, however, occurred in7 months after flower opening. At these7% Brix total soluble solids. At 6.57475767781











6 days (At ripening)% moisture (wet basis)% moisture (wet basis)Months after flower openingMonths after flower openingExperiment 1Experiment 21 day (24 h after induction)0 day (Before induction)8.587.5 76.5757681









6 (At ripening)1 (24 h after induction)0 (Befire induction)8.587.5 7Figure 7. Changes in moisture content (%) of ciku var. Subang at different maturity stagesFigure 8. Rate of change in moisture content (%) of ciku var. Subang during ripening (afterinduction with 5 ppm ethylene) at different maturity stages













8.5 months8 months7.5 monthsExperiment 1Experiment 27 months6.5 months74757677% moisture (wet basis)Days after inductionDays after induction02460246% moisture (wet basis)

7576777980Figure 9. Average scores for
7576777980Figure 9. Average scores for sweetness, flavourand acceptability of ciku var. Subang ripened atdifferent maturity stages0127Average scoreM.Y. Rohani and M.A. Siti Halijah15% Brix (Figure 11). This affects the(Figure 9)lost about 1% of their total soluble solids21%Brix.process. The initial pathway is that ofglycolysis where sugar, especially glucose isin the respiratory process. This can be(Figure (Figure 12) as well as during ripening(Figure 13)harvested between 7.5(Figure 12). At these stages,the fruit contained between 1215% total6.5(Figure 13) and after ripeningless than 10% was found in the fruit tissuesand this amount was insufficient to givegood flavour and taste. All of the fruitsFigure 10. Changes in total soluble solids (% Brix) of ciku var. Subang at different maturity stages1012141624











6 days (At ripening)Months after flower openingMonths after flower openingExperiment 1Experiment 2% Brix% Brix1 day (24 h after induction)0 day (Before induction)8.587.5 76.5101224









6 (At ripening)1 (24 h after induction)8.587.5 7Figure

11. Rate of change in total soluble sol
11. Rate of change in total soluble solids (% Brix) of ciku var. Subang during ripening(after induction with 5 ppm ethylene) at different maturity stages1012141624% Brix% Brix







8.5 months8 months7.5 months7 months6.5 months64200Days after inductionDays after induction1012141618202224642





Experiment 1Experiment 2266Physico-chemical changes during ripening of ciku021018









6 (At ripening)1 (24 h after induction)8.587.5 70210% Total sugars% Total sugarsFigure 12. Changes in total sugars (%) of ciku var. Subang at different maturity stages0123Months after flower openingMonths after flower opening6.5017









6 (At ripening)1 (24 h after induction)8.587.5 7Figure 14. Changes in pH of ciku var. Subang at different maturity stagesFigure 13. Rate of change in total sugars (%) of ciku var. Subang during ripening (afterinduction with 5 ppm ethylene) at different maturity stages46810121416% Total sugars% Total sugars04681016146420Days after inductionDays after inductionM.Y. Rohani and M.A. Siti Halijah(Figure

9). The fruits were acceptable(Figure 9
9). The fruits were acceptable(Figure 9) when the total sugar content15% which was foundin fruits harvested at 7.5(Figure 12)Changes in pH also affect the flavourand taste of the fruits. There was a gradual(Figure14). However, after ripening the pH(Figure 15)The harvest maturity of ciku var. Subangphysico-chemical changes of the fruit. At6.5harvesting. At this stage the fruit have poordevelopment of total sugars. The bestcolour development during ripening. Thein total soluble solids, total sugars andacidity during ripening. There was a highthe fruit tissues after ripening. This gave the8.5months after flower opening the fruitwas already over matured. The fruit softenedThe authors would like to thank Mr John Ng,Mr Abdul Rahman Moidu and MrIsmailThe assistance of Mr Yunus Jaafar was alsoReferencesAbdul Karim, M.N., Ahmad Tarmizi, S. andAbdullah, A.B. (1987). The physico-chemical L.) of Jantungvariety. Pertanika 10(3): 277Abeles, F.B., Morgan, P.W. and Saltveit, M.E., Jr. 2nd ed., p. 182Third National Agriculture Policy 12th ed.Washington, D.C.: Association of OfficialFigure 15.

Rate of change in pH of ciku var. Suban
Rate of change in pH of ciku var. Subang during ripening (after induction with 5 ppmethylene) at different maturity stages4.04.56.5













8.5 months8 months7.5 monthsDays after inductionExperiment 1pH7 months6.5 months6420Days after inductionExperiment 2pH4.04.55.06420 (1984). 14th ed.Virginia: Association of Official AnalyticalPerishable Plant Products, p. 75York: An AVI Book, Van Nostrand ReinholdLatifah, M.N. (1996). Effect of exogenous ethylene L.).Proc. International Conference on TropicalVol. I,Lumpur, p. 367Raziah, M.L., Zaharah, T. and Shahadan, M.Teknol. Buah-buahan 7:Siti Halijah, A. and Tham, S.L. (1996). Fruitdevelopment and maturation of sapodilla cv.Proc. International Conference onTropical Fruits Vol. I,Kuala Lumpur, p. 397Wills, R.B.H., McGlasson, W.B., Graham, D.,Lee, Tintroduction to the physiology and handlingPeringkat kematangan bagi ciku var. Subang semasa dituai mempengaruhi citamengembang) tidak diterima dengan baik. Tahap yang paling baik memetik buahpada masa yang sama. Warna isi bertukar perang kemerahan dan kandung