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Food Chemistry 2018 Journal of Food, Nutrition and Population Health
ISSN: 2577-0586 Page 72
July 23-24, 2018
Rome, Italy
3rd Edition of International Conference on
Agriculture &
Food Chemistry
Kimchi is a group of Korean traditional fermented vegetables,
which includes Pa (green onion) kimchi made of green onion.
The green onion that is known as one of the main ingredients
used for the preparation of various types of kimchi and contains
anti-bacterial sulfur-compounds resulting in delay of the growth
of harmful bacteria, serves as the main material of Pa kimchi.
Lactic acid bacteria (LAB), other important components of
kimchi fermentation, contribute to the bio preservation of kimchi
but may produce biogenic amines (BA) during the fermentation,
posing potential safety risks. This study was conducted to
evaluate BA related risks by measuring BA content in Pa kimchi
samples and assessing bacterial contribution to the BA content.
Total BA content of the samples did not reach the recommended
safety limit 1,000 mg/kg for food. On the contrary, relatively high
levels of vasoactive (histamine and tyramine) and putrefactive
(putrescine and cadaverine) amines were detected in less ripened
Pa kimchi samples, reaching the toxic thresholds of respective
BA. Meanwhile, of the 99 LAB strains isolated from Pa kimchi
samples, 16 strains significantly produced BA in independent in
vitro assays, 14 and two strains were identified as L. brevis and L.
sakei, respectively, through 16s rRNA sequencing. Therefore, it was
assumed that L. brevis could be responsible for BA formation in
Pa kimchi. In addition, there appeared to be negative correlations
between BA content (viz., vasoactive and putrefactive amines)
and acidity (an indicator of kimchi ripening) of Pa kimchi samples.
The results suggest that BA-related risks decrease as Pa kimchi
ripening progresses. The relationship between the successive
change of microbial communities and BA in kimchi needs to be
further investigated to reduce BA formation.
Biography
Jae-Hyung Mah completed his PhD from Korea University, South Korea and
Postdoctoral studies from University of Wisconsin-Madison and Washington
State University, USA. He is a Professor of Food and Biotechnology at Korea
University, South Korea. He published about 50 papers in reputed journals and
has been serving as an Editor-In-Chief, Editorial BoardMember and Referee for
several peer-reviewed journals in Food Science and Technology. His research-
es focus on the analyses of hazardous chemicals and microorganisms in
fermented foods, development of novel protective and preservative strategies
such as application of genetically designed starter culture to food fermenta-
tion and mathematical model studies on inactivation kinetics of food borne
pathogenic and spoilage microorganisms exposed to chemical, physical and
biological intervention treatments.
Biogenic amines in Pakimchi, a Korean kimchi made of green
onion
Jae Hyung Mah, Jun-Hee Lee, Jae Hoan Lee and Young Hun Jin
Korea University, South Korea
Jae Hyung Mah et al., J Food Nutr Popul Health 2018, Volume 2
DOI: 10.21767/2577-0586-C2-006