Studies on Pomerac Syzygium malaccense

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Studies on Pomerac (Syzygium malaccense)

• Candied Fruit Slices

Gail S. H. Baccus-Taylor, Purdey D. Frederick and
John O. Akingbala Food Science Technology Unit
Department of Chemical Engineering, Faculty of
Engineering University of the West Indies St.
Augustine, Trinidad and Tobago
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INTRODUCTION

• Pomerac, botanically identified as Syzygium
  malaccense
• Origin in Malaysia known in Caribbean for over
  100 years tree often used as windbreak (Barbeau,
  1995).
• Fruit has mild-sweet taste pink - red colour
  short 8-day shelf life at 28ºC (Basanta, 1998).

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INTRODUCTION

• High perishability due to thin skin, easily
  damaged if improperly handled

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OBJECTIVE OF RESEARCH

• To produce osmo-dehydrated (candied) pomerac
  slices and to evaluate their storage properties.

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Why use Pomerac ?

• 2 varieties in Trinidad 1) Rookmin, 2) La
  Pastora Special
• Considered an under-utilized, minor or
  lesser-known fruit possesses great market
  potential as fresh, or as processed (value-added)
  products.
• Processed pomeracs reduce wastage improve
  economic return to producer allow for variety
  and preservation for later consumption when fresh
  fruits unavailable.

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Why use Pomerac ?

• Candying of slices simple, inexpensive procedure
  relatively inexpensive equipment.
• Candied pomerac can be utilized in bakery, ice
  cream and confectionery industries.
• Inadequate documentation on local post-harvest
  processing of pomerac

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Materials Methods
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PHYSICO-CHEMICAL ANALYSES

• Colour (fresh fruit candied slices) - Minolta
  Chroma Meter measured weekly during 4-wk storage
  (5C)
• Texture (fresh fruit candied slices) digital
  penetrometer
• pH (fresh fruit candied slices)
• Ascorbic acid (fresh fruit) Ranganna (1977)
• Aw (fresh fruit candied slices) - water
  activity meter

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Proximate Analyses

• Moisture fruit pulp seed
• Ash Fat fruit pulp
• Crude protein, Crude fibre TSS Fruit pulp
  seed

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MICROBIAL ANALYSES

• During 4 week-storage (5C)
• Enumeration of Yeasts Aerobic bacteria
• Detection of Moulds

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SENSORY EVALUATION

• Use of 10 semi-trained panellists to evaluate
  appearance, colour, taste, texture
  acceptability of products
• Use of 5-point Hedonic scale

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STATISTICAL ANALYSIS

• Analysis of sensory evaluation data-Statistical
  Package Minitab, Version 11.21 for Windows
• Differences in means established using ANOVA
• Means, where different, separated at p

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RESULTS DISCUSSION
Table 1. Chemical Composition of Pomerac Fruit
(pulp) and Seeds (g kg-1)
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Table 2. Moisture, Ascorbic Acid Content (g kg-1)
and Texture (mm) of Candied Fruit Slices
Data followed by similar letters are not
different (p 0.05)
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Table 3. Colour of Pomerac and Candied Pomerac
Slices
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Table 4. Yeast Count in Stored Candied Pomerac
Slices
Note - denotes absent
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Table 5. Detection of Moulds in Candied Pomerac
Slices During Storage
Note denotes present - denotes absent
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Table 6. Enumeration of Aerobic Bacteria in
Candied Pomerac Slices
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Table 7. Mean 1,2 Sensory Scores of Candied
Pomerac Slices (3cm)

• Means of ten replicates
• Means with the same letters in a column are not
  different (p 05)

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60ºBrix
50ºBrix
pH
3
0
1
2
3
4
5
Storage Duration (Weeks)
Fig. 1 pH of Stored Candied Pomerac Slices
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Candied Pomerac Slices
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CONCLUSIONS

• Slices of pomerac fruit , 2-3mm-thick, candied by
  dehydrating overnight in 50 and 60B solutions,
  then dried at 40C or 50C, until aw of 0.65
  attained.
• Candied pomerac slices sensorially acceptable.
• Upon storage, pH of candied fruit slices
  decreased probably due to activity of aerobes,
  yeasts and moulds.
• Yeasts moulds appeared in product at Week 2
  storage, probably due to contamination or
  resuscitation.

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CONCLUSIONS

• Mould inhibitor adequate packaging material can
  be used to increase shelf life of candied pomerac
  slices.
• Since over 50 of fruit lost as by- product
  during production of pomerac candy since seeds
  (high in oil) forms significant portion of waste,
  it is desirable to investigate uses for these by-
  products, minimising potential environmental
  problems.

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