CHANGES OF SOME PROPERTIES OF KIWIFRUIT STARCH DURING POSTHARVEST RIPENING

Citation
S. Matsumoto et al., CHANGES OF SOME PROPERTIES OF KIWIFRUIT STARCH DURING POSTHARVEST RIPENING, J JPN SOC F, 40(4), 1993, pp. 262-267
Citations number
NO
Categorie Soggetti
Food Science & Tenology
Journal title
JOURNAL OF THE JAPANESE SOCIETY FOR FOOD SCIENCE AND TECHNOLOGY-NIPPON SHOKUHIN KAGAKU KOGAKU KAISHI
ISSN journal
1341027X → ACNP
Volume
40
Issue
4
Year of publication
1993
Pages
262 - 267
Database
ISI
SICI code
1341-027X(1993)40:4<262:COSPOK>2.0.ZU;2-I
Abstract
The starch was prepared from kiwifruit during post-harvest ripening. ( 1) Scanning electron microscopies showed a gradual disintegration of t issues and a decomposition of a surface of the starch. (2) Photopasteg ram of kiwifruit starch showed that the initial temperature of gelatin ization dropped by ripening, from 66-degrees-C to 64-degrees-C after 6 days storage, and to 62-degrees-C after 12 days storage. Decrease of transmittance was not observed prior to the drop of initial temperatur e of the gelatinization. (3)Kiwifruit starch showed B-pattern on X-ray diffractometry and the pattern did not change during ripening. (4) Ki wifruit starch was debranched by isoamylase and fractionated to three fractions (F-I, F-II and F-III) by gel-filtration on Sephadex G-75. By measuring of lambdamax, it was suggested that F-I was originated from amylose, and F-II and F-III was originated from amylopectin. Amylose (F-1) content increased during ripening from 8.1% to 13.0% after 6 day s storage and 19.1% after 12 days storage. It was estimated that the i ncrease was caused by decomposition of amylopectin. The degree of poly merization of F-II and F-III were in the range of 34 approximately 36 and 14 approximately 16, respectively, throughout the ripening.