INVESTIGATION OF PHYSICOCHEMICAL PROPERTIES, ANTIOXIDANT ACTIVITY AND COLOR STABILITY OF PULP, PEEL AND PUREE OF TWO DRAGON FRUIT VARIETIES (hylocereus SPP.)

1. WELLCOME
TO MY
PRESENTATION

2. Presented By
Mst. ShafinaSabnam
Student No: 1905449
Session:July-December 2020
DEPARTMENT OFAGRICULTURALCHEMISTRY
HAJEE MOHAMMAD DANESH SCIENCE AND TECHNOLOGYUNIVERSITY
DINAJPUR-5200

3. SUPERVISOR
Prof. Dr. Bikash Chandra Sarkar
Chairman
Department ofAgricultural
Chemistry
CO-SUPERVISOR
Prof. Dr. Md. Abdul Hakim
Department ofAgricultural
Chemistry

4. THESIS TITLE
INVESTIGATION OF PHYSICOCHEMICAL
PROPERTIES, ANTIOXIDANTACTIVITY AND COLOR
STABILITY OF PULP, PEELAND PUREE OF TWO
DRAGON FRUIT VARIETIES (hylocereus SPP.)

5. Outlines
 Research Background
 Objectives
 Methodology
 Results
 Conclusion

6. Research Background
 Dragon fruit (Hylocereus spp.) is a promising tropical fruit which can be
cultivated in different tropical and subtropical parts of the world such as
SoutheastAsia
 Dragon fruit is increasingly gaining interest in many countries, including
Bangladesh
 Its popularity is increasing due to its essential nutrients such as vitamins,
minerals, complex carbohydrates, dietary fibers and antioxidants
 But Currently, there is limited literature on dragon fruit properties, its
processed products and constituents as well as potential utilization

7. Cont’d
 Besides being consumed fresh, dragon fruit can also be processed
 Dragon fruit and its products may be used as ingredients for
innovative food products that respond to consumers’interest
 They are widely used in various food products such as sweets,
yogurts, ice creams, pastries, jams, jellies and wines
 A high increase in dragon fruit processing results in high amounts
of waste materials such as peels and seeds

8. Cont’d
 Therefore, the knowledge related to the characterization of dragon
fruit is necessary to improve quality of dragon fruit and its co-
products
 Knowledge regarding the quality of dragon fruit is essential for
the efficient handling of fruit production for equipment design,
processing conditions and quality control
 In this thesis, the experimental work provides a comprehensive
insight into the characteristics (e.g. physicochemical,
antioxidative, microbiological properties) of the whole fruit, peel,
pulp and puree of white & red-flesh dragon fruit

9. Objectives
To study the effects of Physicochemical properties, color
stability of pulp and peel of two dragon fruit varieties
(Hylocereus spp.)
To investigate the effects of antioxidative properties of
white-flesh and red-flesh dragon fruit (Hylocereus
spp.)pulp and purees

10. Methodology
A schematic layout of the experimental set-up of this chapter
is presented in below Figure

11. Cont’d
Experimental Site
 The Research work was performed in the laboratory of the
Department of Agricultural-chemistry, Hajee Mohammad Danesh
Science and Technology University, Dinajpur & in the laboratory of
Bangladesh Agricultural Research Institute.
 Test fruit: White-flesh dragon fruit & Red-flesh dragon fruit
 Number of test sample: White-flesh dragon fruit 15 pcs & Red-
flesh dragon fruit 15 pcs
 Experimental period: 15th June to 15th October, 2020.
 Experimental Design: One-way analysis of variance (ANOVA).

12. Fig: Peeling Red Dragonfruit
Fig: Cutting Red Dragonfruit Fig: Cutting White Dragonfruit
Fig: Peeling Fig: Weighing Fig: Cutting
Fig: Puree of Red Dragonfruit
Fig: Red & White Dragonfruit
Fig: Peeling White Dragonfruit Fig: Puree of White Dragonfruit

13. Cont’d
 The experimental data for the properties of the whole fruit, peel, pulp
(flesh without seeds) and puree (flesh containing seeds) of the two
species of dragon fruit are discussed separately
 The dimension and weight of the whole dragon fruit were measured. The
weight proportion of peel, pulp and seed was also estimated based on the
whole fruit
 The physicochemical properties such as dry matter, pH, vitamin C
content, total betacyanin content and colour parameters of dragon fruit
peel were determined
 A whole set of nutritional properties (e.g. protein, fat, ash, carbohydrates
and total dietary fibre contents), total plate count, antioxidative properties

14. Cont’d
 Two species of dragon fruit, i.e. white-flesh with red-peel (H. undatus)
and red-flesh with red-peel (H. polyrhizus) originating from Thailand,
were obtained from BAU & BARI, Bangladesh
 Fruit was washed under running tap water and hand-peeled
 To obtain the homogeneous dragon fruit pulp (without seeds), the dragon
fruit flesh was cut into pieces and extracted by using a juice extractor
 In contrast, small pieces of the dragon fruit flesh were homogenized in a
food blender (BL 9170 Fritel, Belgium) for 30 sec, and then passed
through a 38-mesh sieve and a 32-mesh sieve
 The dragon fruit samples were then stored at -18 °C until further
characterization

15. RESULTS AND
DISCUSSION

16. Physical Properties of the Dragon Fruit
Parameter BAU Dragon fruit-1 (White-flesh) BARI Dragon fruit-1 (Red-flesh)
Fruit dimension (cm)
Length 9.42 ± 1.2 a 10 ± 0.9 b
Diameter 6.86 ± 1.7 a 7.22 ± 1.6 b
Fruit weight (g/fruit)
Peel 76.7 ± 3.2 a 86.8 ± 1.0 b
Pulp 224.72 ± 8.8 a 224.56 ± 2.7 b
Seed 32.78 ± 1.0 a 34.64 ± 0.4 b
Whole fruit 346 ± 13.0 a 379.8 ± 4.1 b
Fruit proportion (%,w/w)
Peel 24.51 ± 0.7 a 25.27 ± 0.9 a
Pulp 67.61 ± 0.7 a 64.71 ± 0.8 a
Seed 9.85 ± 0.8 a 10.17 ± 0.9 a
Values are given as mean ± SD (N=30) and the superscripts within
each row indicate significant differences (p < 0.05)

17. Analytical Procedure
Parameter Methods of Determination
pH Electrochemical methods & milivoltmeter
(pH meter)
Dry matter Wet basis (%)
Protein Kjeldahl method (AOAC)
Ash Dry ashing method
Crude fat Soxhlet method
Carbohydrates Molisch”s test method
Total dietary fibre Enzymatic- Gravimetric Method (AOAC)
Vitamin C Ultraviolet (UV) Spectrophotometry
Betacyanin Quantitive Determination
Colour parameter Colorimetry
Total plate count (104 CFU/g) Total viable count (TVC)
Total phenolic (mg GA/100 g) UV spectrophotometer
FRAP index ET-based method
DPPH (ìg GA/g) The HPLC method

18. Physicochemical Properties of the
Dragon Fruit Peel
Parameter BAU Dragon fruit-1 (White-flesh) BARI Dragon fruit-1 (Red-flesh)
pH 4.70 ± 0.005 a 4.69 ± 0.004 a
Dry matter (g/100 g) 9.21 ± 0.24 a 7.55 ± 0.28 b
Vitamin C (mg/100 g) 4.09 ± 0.17 a 13.1 ± 0.09 b
Betacyanin (mg/100 g) 10.50 ± 0.24 a 21.08 ± 0.32 b
Colour parameter
L* (lightness) 30.06 ± 0.28 a 29.58 ± 0.23 a
a* (redness) 17.49 ± 0.54 a 17.14 ± 0.72 a
b* (yellowness) -2.51 ± 0.12 a -0.97 ± 0.16 b
Values are given as mean ± SD (N=3) and the contents are based on fresh weight basis. The
superscripts within each row indicate significant differences (p < 0.05)

19. Characteristics of the Dragon
Fruit Pulp
Parameter BAU Dragon fruit-1 (White-flesh) BARI Dragon fruit-1 (Red-flesh)
pH 4.67 ± 0.006 a 4.50 ± 0.003 b
Density (g/cm3) 1.10 ± 0.02 a 0.99 ± 0.02 a
Dry matter (g/100 g) 8.93 ± 0.24 a 9.01 ± 0.17 a
Protein (g/100 g) 0.20 ± 0.02 a 0.28 ± 0.004 b
Ash (g/100 g) 0.96 ± 0.01 a 1.18 ± 0.01 b
Crude fat (g/100 g) 0.50 ± 0.02 a 0.45 ± 0.02 a
Carbohydrates (g/100 g) 9.54 ± 0.07 a 8.45 ± 0.07 b
Total dietary fibre (g/100 g) 0.55 ± 0.03 a 0.97 ± 0.06 b
Vitamin C (mg/100 g) 5.50 ± 0.32 a 10.85 ± 0.53 b
Betacyanin (mg/100 g) Not detected 16.53 ± 0.17

20. Cont’d
Parameter BAU Dragon fruit-1 (White-flesh) BARI Dragon fruit-1 (Red-flesh)
Colour parameter
L* (lightness) 39.09 ± 0.77 a 26.25 ± 0.65 b
a* (redness) -0.54 ± 0.06 a 10.15 ± 0.68 b
b* (yellowness) -3.55 ± 0.13 a -1.93 ± 0.42 b
Total plate count (104 CFU/g) 2.99 ± 0.15 a 3.31 ± 0.18 b
Total phenolic (mg GA/100 g) 11.21 ± 0.13 a 15.33 ± 0.49 b
FRAP index 0.3467 ± 0.0058 a 0.5533 ± 0.0057 b
DPPH (ìg GA/g) 17.56 ± 0.56 a 22.65 ± 0.67 b
Values are given as mean ± SD (N=3) and the contents are based on fresh weight basis.
The superscripts within each row indicate significant differences (p < 0.05)

21. Characteristics of the Dragon Fruit Puree
Parameter BAU Dragon fruit-1 (White-flesh) BARI Dragon fruit-1 (Red-flesh)
Yield of flesh (%) 20.06 ± 0.66 a 36.95 ± 0.74 b
Yield of juice (%) 80.20 ± 0.64 a 64.05 ± 0.71 b
Yield of seed (%) 1.05 ± 0.01 a 0.96 ± 0.03 a
pH 4.55 ± 0.001 a 4.62 ± 0.001 b
Density (g/cm3) 1.02 ± 0.05 a 0.98 ± 0.06 a
Dry matter (g/100 g) 15.56 ± 0.09 a 16.98 ± 0.13 a
Protein (g/100 g) 0.63 ± 0.04 a 0.83 ± 0.05 b
Ash (g/100 g) 1.25 ± 0.001 a 1.55 ± 0.001 b
Crude fat (g/100 g) 0.62 ± 0.03 a 0.57 ± 0.03 a
Carbohydrates (g/100 g) 12.06 ± 0.04 a 13.11 ± 0.05 b
Total dietary fibre (g/100 g) 0.97 ± 0.01 a 2.16 ± 0.09 b
Vitamin C (mg/100 g) 8.22 ± 0.21 a 16.03 ± 0.56 b
Betacyanin (mg/100 g) Not detected 14.82 ± 0.19

22. Cont’d
Parameter BAU Dragon fruit-1 (White-flesh) BARI Dragon fruit-1 (Red-flesh)
Colour parameter
L* (lightness) 39.48 ± 0.67 a 26.15 ± 0.29 b
a* (redness) 0.38 ± 0.08 a 9.13 ± 0.71 b
b* (yellowness) 0.14 ± 0.11 a -2.45 ± 0.10 b
Total plate count (104 CFU/g) 2.16 ± 0.12 a 3.50 ± 0.27 b
Total phenolic (mg GA/100 g) 17.95 ± 0.31 a 35.02 ± 0.67 b
FRAP index 0.3900 ± 0.0079 a 0.5827 ± 0.0063 b
DPPH (ìg GA/g) 30.43 ± 0.07 a 63.53 ± 0.89 b
Values are given as mean ± SD (N=3) and the contents are based on fresh weight basis.
The superscripts within each row indicate significant differences (p < 0.05)

23. Conclusion
 The work provides further insight into the important characteristics
of the different fractions (the whole, peel, pulp and puree) of the
two species of dragon fruit
 By-products left over are of great interest because they may
contain some beneficial components
 The dragon fruit could possibly be applied as a promising source of
natural food coloring
 The antioxidative properties of the red-flesh dragon fruit were
around twice the amount compared to the white-flesh dragon fruit

24. Cont’d
 However, the taste of Red Dragon Fruit is the BEST! Its sweetness is
double of White-fleshed Dragon Fruit, and it has no sour taste
 It's rich in antioxidants like flavonoids, phenolic acid, and betacyanin
 It's naturally fat-free and high in fiber which may help lower blood
sugar
 It contains prebiotics, which are foods that feed the healthy bacteria
called probiotics in gut
 It can strengthen immune system

25. Cont’d
 It is an established fact that deep red fruits and vegetables
contain more antioxidants
 That's why, red dragon fruit has higher amount of
antioxidants than white one
 This makes it a great food for healthy eyes, blood, and skin
 Accordingly, the results are very important for the study of
the quality of dragon fruit & red dragon fruit is
recommended for cultivate in Bangladesh

26. Acknowledgement