Abstract:
Jackfruit (Artocarpus heterophyllus Lam) is in
high demand by Asians. It is large and difficult to peel,
therefore, consumers prefer to buy jackfruit as a ready to cook
product. Jackfruit is highly perishable. It ripens faster during
the shelf life, and soon become unfit for cooking. Development
of volatile compounds which contribute to flavour and aroma
takes place during the ripening process. The aim of this study
was to investigate the effect of application of 1% alginate-based
and agar-based edible coatings on retention of volatile
compounds developed in pre-cut jackfruit during a shelf life of
5 days under refrigerated conditions (6+10C). The alginate
coating was developed by dissolving alginate and glycerol in
distilled water. CaCl2 was used as a cross-linking agent in the
alginate-based coating. The agar coating was also developed by
dissolving agar and glycerol in water. Jackfruit of initial brix
6.23 + 0.39 were selected for the study. Volatile compounds were
detected by SPME-GC-MS technique on a DB-225MS column
in uncoated, alginate coated and agar coated jackfruit on the
2nd day and 5th day of the shelf life. Esters, benzenic
derivatives, pyridine derivatives, volatile alkanes, volatile
alkenes, terpenes, aldehydes, ketones and alcohols were detected
during the analysis. Compounds which were detected only from
alginate coated samples were 1,2-dichlorobenzene, dimethyl(4-
bromo-phenoxy)pentadecyloxy silane, 1,4-dihydro-1,4-
methanonaphthalene, 4-(1-methyl-2-pyrrolyl)-2,6-
diphenylpyridine, vanillin, trans-octahydro-1H-inden-1-one,
and dimethyl-silanediol. These can be attributed as volatile
compounds related to alginate. Compounds like 2,5-bis(1,1-
dimethylethyl)phenol, tetradecanal, hexadecanal and transdodec-
5-enal were only detected from agar coated samples.
These can be attributed as volatile compounds related to agar.
Volatile compounds like 6-methyl-2-heptanone, naphthalene,
tridecane, tetradecane, pentadecane and hexadecane were lost
from the uncoated jackfruit sample during the shelf life and
these compounds could be preserved in pre-cut jackfruit by the
applied alginate and agar coatings.
