CAROTENOIDS 



In the case of French beans, the variation in the carotene concentra- 

 tion of the beans during maturation does not parallel that of the pods. 

 At early maturity the beans reach a value much higher than that of the 

 pods, this then drops considerably at full maturity ; the values for the 

 pods vary little until they become markedly overmature. In spite of 

 this, at all stages of development a pod contains larger amounts of 

 carotene than do the beans which it contains. ^^^ T^g carotene dis- 

 tribution in beans and peas is very similar to that of leaves ; for example, 



Table 6. — Carotene Content of some varieties or strains of Peas.* 



♦ From Heinze, P. H., Hayden, F. R., and Wade, B. L. (1947), 

 Plant Physiol, 22, 548. 



soya beans ' * * and Lima beans * * • contain 80-90 per cent, of the (3- 

 isomer. Although few data are available concerning xanthophylls in 

 beans and peas, it is likely that they are very similar to leaf xantho- 

 phylls. Nakamura and Sakan ^ " ^ report taraxanthin, a fucoxanthin- 

 like pigment {see p. 132), and an eloxanthin-likt pigment {see p. 57) as 

 well as lutein (xanthophyll) in soya bean oil. Confirmation of these 

 somewhat unexpected findings is required before they can be un- 

 reservedly accepted. Unpredictable oxidative changes may have taken 

 place during the preparation of the oil. The carotene content of a 

 number of seeds is recorded in Appendix I {see p. 294). 



44 



