Abstract:

In this experiment, the major nutrients and soluble protein contents in red kidney beans from the United Kingdom
and Shanxi province, China were analyzed. The extraction, functional properties and subunit composition of albumin in
red kidney beans from the two geographic origins were studied. The results showed that the major nutritional composition
of British red kidney beans was significantly different from that of those from Shanxi, and albumin was the most abundant
soluble protein in both samples, accounting for 74.08% and 66.50% of the total amount of soluble proteins, respectively,
which also contained 10.08% and 13.05% globulin, 7.23% and 7.24% gluten, and 6.79% and 6.12% prolamin, respectively.
Material-to-liquid ratio had an extremely significant impact (P < 0.01) on the extraction rate of albumin from British red
kidney beans and a significant impact (P < 0.05) on the extraction rate of albumin from Shanxi red kidney beans. Extraction
temperature and time were also significant factors for the extraction of albumin from British rather than Shanxi red kidney
beans (P < 0.05). Protein Isoelectric point for both samples was pH 4.7. Electrophoresis analysis showed that the distribution
of albumin in these two samples was substantially the same in the range of 19.0–44.0 kD, although differences in the range
of 44.0–97.4 kD were observed.

Key words: British red kidney bean, Shanxi small red kidney bean, nutrients, protein extraction, functional properties, electrophoresis