ISSN:
1750-3841
Quelle:
Blackwell Publishing Journal Backfiles 1879-2005
Thema:
Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
,
Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
Notizen:
SUMMARY— Although considerable work has been done on the sediment sometimes formed in clarified apple juice upon storage, the sediment itself has not been completely characterized as to its chemical composition and the precursors involved. The fact that the sediment yielded phloroglucinol and protocatechuic acid upon alkali fusion and amino acids upon acid hydrolysis indicated that the sediment was a polymeric phenolic-protein complex. The variable nitrogen, mineral and ash contents of different sediments and the variable amino acid composition of the protein fraction in conjunction with the behavior of the sediments on Sephadex gel columns indicated the heterogeneous nature of this material. Poly-amide thin-layer chromatography and calorimetric analyses have shown that leucoanthocyanidins and catechins are the main precursors of the polymeric phenolic component. Chlorogenic acid appears to play an insignificant role in sediment formation. The amino acid composition was determined by the use of an amino acid analyzer and the mineral content was estimated, quantitatively, by means of an atomic absorption spectrophotometer.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1111/j.1365-2621.1968.tb01361.x
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