establishment of a physical basis of mango maturity using a

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ESTABLISHMENT OF A PHYSICAL BASIS OF MANGO MATURITY USING A UNIVERSAL TESTING MACHINE

RENMAR JAMES PERALTA DACONES

SUBMITTED TO THE FACULTY OF

COLLEGE OF ENGINEERING AND AGRO-INDUSTRIAL TECHNOLOGY UNIVERSITY OF THE PHILIPPINES LOS BAÑOS

IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF BACHELOR OF SCIENCE IN AGRICULTURAL ENGINEERING

(MAJOR IN AGRICULTURAL BIO-PROCESS ENGINEERING)

MARCH 2010

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The thesis attached hereto, entitled “ESTABLISHMENT OF A PHYSICAL BASIS OF MANGO MATURITY USING A UNIVERSAL TESTING MACHINE”

prepared and submitted by RENMAR JAMES PERALTA DACONES in partial fulfillment of the requirements for the degree of BACHELOR OF SCIENCE IN AGRICULTURAL ENGINEERING, is hereby accepted.

____________________ ____________________

Dr. Edralina P. Serrano Member, Guidance Committee

____________________

Date Signed

Dr. Engelbert K. Peralta Member, Guidance Committee

____________________

Date Signed

___________________

Dr. Kevin F. Yaptenco

Adviser and Chairman, Guidance Committee ____________________

Date Signed

___________________ __________________

Dr. Kevin F. Yaptenco Chairman, Agricultural and Bio-

Process Division ____________________

Date Signed

Dr. Arnold R. Elepaño Director, Institute of Agricultural

Engineering

____________________

Date Signed

____________________

Dr. Arsenio Resurreccion Dean, College of Engineering and

Agro-Industrial Technology ____________________

Date Signed

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TABLE OF CONTENTS

Chapter Page

Title Page i

Approval Page ii

Biographical Sketch iii

Acknowledgement iv

Table of Contents vi

List of Tables viii

List of Figures ix

List of Appendix Tables xii

Abstract xv

I INTRODUCTION

Background of the Study 1

Significance of the Study 4

Objectives of the Study 5

Time and Place of the Study 6

II REVIEW OF RELATED LITERATURE

Manila Super Mango 7

Maturity or Ripeness of Fruits 8

Maturity Determination of Mango 9

Compressive Strength 11

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Force-deformation Curve 12 Instron Universal Testing Machine (IUTM) 15

Deformation by Machine 16

Force-deformation Ratio as Index of Papaya Maturation 18

Mango Firmness Sorter 19

III METHODOLOGY

Mango Sample Collection 21

Compression Tests 24

Chemical Analysis 28

Sensory Analysis 31

Statistical Analysis 31

IV RESULTS AND DISCUSSION

Compression of Mango Samples 34

Physical Characteristics of Fruit Samples After

Compression 42

Chemical Analysis 47

Sensory Analysis 50

V SUMMARY AND CONCLUSION 52

VI RECOMMENDATIONS 55

REFERENCES 56

APPENDICES 58

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LIST OF TABLES

Table Title Page

1 Average values of stiffness (N/m) of mango samples at

different deformations and maturities 34 2 Average deformations measured by the IUTM during

compression at different maturities 35

3 Mean stiffness of mangoes at different maturities and compressed at different deformations with their

corresponding Duncan grouping 39

4 Average of the maximum force applied to the mangoes

until rupture 42

6 Average values of TSS, TA and pH of mango samples at different maturities with their corresponding Duncan

grouping 48

6

7

Average values of the ratio TSS/TA of mango samples at different maturities with their corresponding Duncan grouping

Average sensory test values of matured mangoes with their DMRT grouping

49

50

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LIST OF FIGURES

Figure Title Page

1 Top mango producing regions in the Philippines in 1998 3

2 Mature and ripe mangoes 8

3 Diagram of the Force-Deformation curve for materials with

bioyield point and rupture (ASAE, 1997) 13 4

5

The Instron Universal Testing Machine at the Rhological Properties Laboratory (ABPROD)

The harvesting of Mango sample in a backyard farm at Burgos, La Union

16

22 6 Newly harvested mango samples 95 days after flower

induction 22

7 Mango samples sorted for uniformity of size and shape 23 8 Mango samples being placed in a “kaing” before transport 23

9 Schematic diagram of the probe used in the experiment 25

10 Experimental set-up 25

11 Mango samples 95 DAFI compressed until rupture 26 12 Mango samples 95 DAFI compressed at 0.6 mm

deformation 26

13 Mango samples 95 DAFI compressed at 0.9 mm

deformation 27

14 Mango samples 95 DAFI compressed at 1.3 mm

deformation 27

15 Preparation of mango samples for chemical analysis 29

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16 Determination of the Total Soluble Solids of the mango

samples using a refractometer 29

17 Determination of the Titratable Acidity of the mango

samples 30

18 Determination of pH of the mango samples using an

analog pH meter 30

19 Sensory Evaluation Form 32

20 Methodology Flowchart 33

21 Stiffness of the mango samples at 0.6 mm deformation

and rupture 36

and rupture 37

and rupture 38

24 Average values of stiffness at different maturities 40 25 Average maximum force applied at each deformation and

maturity 41

26 Mango samples (95 DAFI) before and after compression at

0.6 mm deformation 43

27 Some of the compressed mango samples at different

deformations and maturities 43

28 Mango samples at 95 DAFI that were compressed until

rupture 44

29 Mango samples harvested at 95 DAFI and compressed to

0.6 mm deformation at table ripe stage 45 30 Mango samples harvested at 95 DAFI and compressed to

0.9 and 1.3 mm deformation at table ripe stage 46 31 Mango sample (105 DAFI) deformed to 1.3 mm at table

ripe stage 46

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32 Mango samples (115 DAFI) compressed at different

deformations at table ripe stage 47

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LIST OF APPENDIX TABLES AND FIGURES

Appendix Table

Title Page

1 Stress, Stiffness and Deformation of 95 DAFI mango

samples (0.6 mm Deformation) 59

samples (Rupture) 62

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17 Results of Sensory Analysis performed on 10 respondents 75 18 Stiffness (N/m) of mango samples applied with

compression of 0.6 mm deformation at different maturity

stages 76

19 Stiffness (N/m) of mango samples applied with compression of 0.9 mm deformation at different maturity

stages 77

20 Stiffness (N/m) of mango samples applied with compression of 1.3 mm deformation at different maturity

stages 78

21 Stiffness (N/m) of mango samples ruptured at different

maturity stages 79

22 Total Soluble Solids (TSS) measurement of mango samples tested upon harvest and 10 days after harvest at

different maturity stages 80

23 Titratable Acidity (TA) measurement of mango samples tested upon harvest and 10 days after harvest at different

maturity stages 81

24 pH measurement of mango samples tested upon harvest

and 10 days after harvest at different maturity stages 82 25 Sample Force-deformation curve for mangoes

compressed until rupture 83

26 Sample Force-deformation curve for mangoes

compressed until 1.3 mm 84

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27 Sample Force-deformation curve for mangoes

compressed until 0.9 mm 85

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ABSTRACT

Renmar James P. Dacones, College of Engineering and Agro-Industrial Technology, University of the Philippines Los Baños, 2009. Establishment of a Physical Basis of Mango Maturity using a Universal Testing Machine.

Adviser: Dr. Kevin F. Yaptenco

A study to develop a method or basis for an objective measurement of mango maturity was conducted using ‘Carabao’ mangoes ranging from maturities of 95 –125 days of flower induction (DAFI). It aimed to determine some of the mechanical characteristics of the fruit like force-deformation curve, and fracture force/load at different number of days after flower induction; deformation where there is no damage occurred. Mango samples were subjected to compressions at different deformations (0.6 mm, 0.9 mm and 1.3 mm) using the Instron Universal Testing Machine model 4411 at the Rheological Properties Laboratory (ABPROD).

The chemical characteristics namely: Total Soluble Solids (TSS), Titratable Acidity (TA) and pH were determined at the PHTRC in UPLB. The sensory characteristics of the fruits were also determined by ten respondents.

Results showed that the highest value of stiffness was observed at 105 DAFI with 0.031 N/m and the lowest value was 0.025 N/m at 125 DAFI. The values of the chemical properties at the green stages show no significant differences from each other. The sensory tests show the highest evaluations at 115 DAFI and lowest evaluations at 95 DAFI. The values of the chemical and sensory analysis show that the optimum eating condition of the mangoes is at 115 DAFI and the worst eating condition is at 95 DAFI. There was no damage incurred in any of the deformations that the fruits were subjected in.

This study recommends that stiffness can be used as a maturity index for mango fruits. But the trend of the stiffness increases from 95 DAFI to 105 DAFI then decreases at 115 DAFI. So the values of stiffness at 95 and 115 DAFI can be the same. But the results verified if the measurement of stiffness is accompanied by other non-destructive maturity indices like visual characteristics of the fruit and by floatation method.