The effects of Malay herbs on the storage stability of chilled ‘keropok lekor’ / Azni A. Aziz

‘Keropok Lekor’ is a famous traditional cuisine especially in the East Coast of
Malaysia. The primary ingredients are fish, flour, sugar and salt. This study was
conducted on ‘Keropok Lekor’ to observe the storage stability for 12 days at chilled
temperature (4°C) after adding mixed local herbs. The formulation without any
incorporation was used as control. The other formulations were incorporation with
dry mix Malay herbs, incorporation with wet mix Malay herbs and another one is
incorporation with BHA/BHT as a comparison between synthetic and natural plant
antioxidant. Analysis that was carried out is chemical analysis which evaluated
through measurement of primary (Peroxide Value) and secondary (Thiobarbituric
Acid Value) oxidation products. Microbiological determinations included the Total
Plate Count and Mould and Yeast Count. Sensory evaluation tests were also carried
out. Dry and wet mix herbs of P. hydropiper and C. asiatica resulted in significant
(P< 0.05) inhibition of lipid peroxidation as compared to control sample. At initial,
the Thiobarbituric Acid Value obtained was not significantly different than to
‘Keropok Lekor’ that was added with BHA/BHT. Total plate count showed a high
count for all the samples. But, the treated samples were significantly lower (P<0.05)
than control until day 9 of storage. Mould and Yeast Count however showed a lower
count than Total Plate Count whereby control was significantly higher (P<0.05) than
the other treated samples throughout the storage time. The highest overall
acceptability in sensory evaluation was the ‘Keropok Lekor’ incorporated with wet
herbs. In conclusion, the best antioxidative and antimicrobial effects were obtained
from the ‘Keropok Lekor incorporated with BHA/BHT. But the incorporation of
‘Keropok Lekor’ with natural herbs also effectively reduced the lipid peroxidation
which shows antioxidative effect up to 9 days of storage. Study showed that not
much antimicrobial effect was observed for the treated samples.