|
KMID : 0903520040470040409
|
|
Journal of the Korean Society of Agricultural Chemistry and Biotechnology
2004 Volume.47 No. 4 p.409 ~ p.413
|
|
|
Quality Changes of a Fully Ripe Korean Native Pumpkin, Yangsan, during Long-term Storage, and High Temperature and Pressure Treatment
|
|
Youn Sun-Joo
Jeong Byeong-Ryong
Kang Sun-Chul
|
|
|
Abstract
|
|
|
|
We have studied quality changes of fully ripe fruit of Korean native pumpkin ‘Yangsan’ regarding the following parameters: pH, sugar content, weight, water content, contents of crude protein and amino acids during 60 days storage at room temperature. As the results, there was no changes in sugar contents according to the storage period, but pH was changing to a little acidic direction with slight decrease in weight and water content. Contents of total crude proteins and comprising amino acids were increased during the storage period. The main contents of amino acids of the Korean native pumpkin, Yangsan, were glutamic acid (15.5%), aspartic acid (10.1%), lysine (8.7%), valine (7.5%), leucine (7.1%) and alanine (6.6%), which were not highly influenced during storage period. Additionally we have investigated the content of free amino acids and color changes during processing of Yangsan under high temperature at 121oC and high pressure at 1 kg/cm2. In fully ripe fruits, a total of 29 kinds of free amino acids were detected including 8 kinds of essential amino acids (histidine, isoleucine, leucine, lysine, phenylalanine, methionine, threonine and valine). More than 35% of total free amino acids were aspartic acid (20.3%) and asparagine (15.4%); ornithine, citrullin, and arginine, which are related to Ornithine cycle, were also detected in fully ripe fruits. But when treated with high temperature and high pressure, glutamic acid and arginine were decreased rapidly whereas ammonium chloride was relatively increased. Moreover “b” value as yellow color indicator was decreased from 17.45 to 9.14 while treated for 60 minutes with high temperature and pressure, caused by the degradation of β-carotene and other yellowish pigments in Yangsan.
|
|
|
KEYWORD
|
|
|
Korean native pumpkin, quality changes, free amino acids, essential amino acids, ornithine cycle
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|
|