Extraction Conditions and Green Index of Green Pigments from Discolored Garlic

녹변된 마늘의 색소 추출 조건과 Green Index

  • Published : 2005.08.31


Extraction conditions, spectrometric, and sensory properties of pigment extracts from green discolored garlic (GDG) were studied for development of green index to evaluate degree of green discoloration of garlic. GDG pigments were extracted using polar solvents, such as methanol, ethanol, and water. Methanol with 1% HCl resulted in highest extraction of green pigments. Extraction of pigments was affected by temperature, and extracted pigments were partially destroyed at high temperatures. Optimum conditions for extraction of green pigments were $20^{\circ}C$ for 30 min. Because green pigments are unstable at room temperature, and no method has been reported to evaluate degree of green discoloration of garlic, color chart was designed by mixing varying amounts of control and GDG. High correlation was observed between sensory scores and "a" value of color chart samples (y=-3.465x - 11.676) with $R^2$ of 0.993. Green index (GI) was developed based on linear regression equation between sensory scores and "a" values. Sensory panel recognized green discoloration of garlic at $GI{\geq}3.0$. GI developed in this study could be utilized to evaluate degree of green discoloration of garlic during cold storage and distribution of garlic.


  1. Bea RN, Lee SK. Factors affecting greening and its control methods in chopped garlic, J. Korean Soc. Hort. Sci. 31: 358-360 (1990)
  2. Song JC, Park HJ. Physical, Functional, Textural and Rheological Properties of Food, Ulsan University, Kyungnam. pp. 805-806 (1995)
  3. Kwon TW, Kim BS, Park NH, Park MH. Inhibition of discoloration in chopped garlic. Korean patent 1990-0008827 (1990)
  4. Imai S, Akita K, Tomorake M, Sauad H. Blue pigment formation from onion and garlic. p. 94. In: IFT Annual Conference (1996)
  5. Cho JS, Ku KH, Kim WJ. Effects of heating, pH, salts and organic acids on color changes of ground garlic. Korean J. Food Sci. Technol. 31: 399-405 (1999)
  6. Kim SJ, Rhim JW, Lee LS, Lee JS. Extraction and characteristics of purple sweet potato pigment. Korean J. Food Sci. Technol. 28: 345-350 (1996)
  7. Kim DM, Kim KH. On the development of flesh greening of the stored garlic. Korean J. Food. Sci. Technol. 22: 50-55 (1990)
  8. Bea RN Lee SK. Factors affecting browning and its control methods in chopped garlic. J. Korean Soc. Hort. Sci. 31: 213-218 (1990)
  9. Kim KO, Lee YC. Sensory Evaluation of Food, Hakyeunsa. pp. 186-188 (1989)
  10. Joslyn MA, Sano T. The formation and decomposition of green pigment in crushed garlic tissue. J. Food Sci. 21: 10-13 (1956)
  11. Lee YC, Hwang JB. Inhibition of flesh greening of the stored garlic. Korean patent 0296548 (2001)
  12. Park MH, Kim HK, Park NH, Jo KS, Kim BS, Park HW, Kwon DJ, Lee DS. Long period preservation and development of product in spicy foods. KFRI report (1990)
  13. Park JY, Kim BS, Park NH, Park MH, Kim SS. Long period preservation of chopped garlic. Korean patent 1995-0012617 (1995)
  14. Mahony MO. Sensory evaluation of food (statistical methods and procedures). Marcel Dekker Inc., New York. pp. 153-156 (1985)
  15. Baek YH, Jang TJ, Shin JK, Kim KH, Kim MO. Method of production of chopped garlic in inhibited greening and browning. Korean patent 1996-0040190 (1996)