The Recovery of Polyphenols from PVPP and Their Antioxidant Capacity
MBAA TQ vol. 45, no. 3, 2008, pp.
283-285 |
VIEW ARTICLE
Charles W. Bamforth and J. Caleb May. Department of Food Science &
Technology, University of California, Davis, CA 95616-8598.
Abstract
There was incomplete recovery of polyphenols during washing of
polyvinylpolypyrollidone (PVPP) that had been used to treat beer. A caustic
agent, at most, recovered 20% of the polyphenols (although commercial practices
generally involve the use of elevated temperatures, the agent was used at
ambient temperature). Repeated washing with deionized water recovered 42% of the
polyphenols, while refluxing with alcohol recovered almost 30% of the
polyphenols from the PVPP. Recovered polyphenols retained their antioxidant
potential. In a separate feature of this investigation, it was confirmed that
different products displayed differing antioxidant potentials depending on the
assay employed. However, in one assay (hydroxyl scavenging) beer fared better
than red wine, even though assays were not normalized for polyphenol content and
the levels of the latter in red wine were far higher.
Keywords: antioxidant, assay, polyphenols, PVPP, recovery
S�ntesis
La recuperaci�n de polifenoles en el lavado de polivinilpolipirolidona (PVPP)
despu�s del tratamiento de cerveza fue incompleta. Un agente alcalino recuper�,
a lo sumo, un 20% de los polifenoles a una temperatura de ambiente (aunque
normalmente se utilizan temperaturas m�s altas). Lavados repetidos con agua
desionizada recuper� 42% de los polifenoles del PVPP, mientras que el reflujo
con alcohol recuper� el 30%. Los polifenoles recuperados mantuvieron su
potencial antioxidante. Otra �rea investigada confirm� que diferentes productos
mostraron diferentes potenciales antioxidantes dependiendo del m�todo de
an�lisis utilizado. En un tipo de ensayo (�hydroxil scavenging�), cerveza
result� mejor que vino tinto (el ensayo no estuvo normalizado seg�n contenido de
polifenoles y los niveles de estos en el vino tinto eran m�s altos).
Palabras claves: antioxidantes, ensayo, polifenoles, PVPP, recuperaci�n
