K Nn mK - Amecamex.org.mx

mg pectin/g fruit
500
450
400
350
300
250
200
150
100
50
0
FSB1-2004
Food Science and Biotechnology in Developing Countries
0 10 20 30 40 50 60 70
Time of cooking
Fig. 3 Yield of pectin in mg extracted with citric acid.
0% citric aid
0.5 % citric acid
1 % citric acid
The fiber obtained after extracting the soluble pectin, was also rich in pectin which could
be extracted by treatment with citric acid. The results of the study on the optimization of
citric acid concentrations and the treatment times are presented in figure 3; the best
yield of 441 mg pectin was obtained at 0.5% citric acid with a cooking time of 60 min.
Table 2 depicts the characterization of different pectin obtained in this study. Similar
amounts of pectin were obtained after aqueous extraction in flabedo, albedo and
rind completes while the best solubilization of 23 % was achieved with citric acid
extraction in albedo. This different pectin had more than 50% galacturonic acid
indicating their purity and high molecular weights. The highest degree of methylation
was determinate for the pectin obtained with citric acid extraction. Acid-soluble pectin
with a high DM has been reported from citrus 6 .
5