Chapter 6B
Peptides
M. Victoria Moreno-Arribas, Mar ́ıaAngeles Pozo-Bay ́ on, ́
and M. Carmen Polo
Contents
6B.1 Introduction...................... ........................................ 191
6B.2 Analytical Methods................ ........................................ 192
6B.2.1 Spectrophotometric Methods. ........................................ 192
6B.2.2 SamplePreparationforPeptideAnalysis............................... 192
6B.2.3 SeparationbyChromatographicTechniques ............................ 196
6B.2.4 Separation by Electrophoretic Techniques........................ ...... 198
6B.2.5 Detection Methods......... ........................................ 199
6B.2.6 Determination of Amino Acid Composition and Sequence in Peptides ...... 200
6B.3 OriginandPeptideCharacterization .......................................... 200
6B.4 PropertiesofWinePeptides ................................................. 208
6B.5 Conclusions .............................................................. 209
References ............................................................... 209
6B.1 Introduction
Peptides form a heterogeneous group of compounds, due to the wide range of
structures (amino acid composition andsequence) in which these compounds may
appear. Generally speaking, the term oligopeptides, or low-molecular-weight pep-
tides, refers to peptides with 10 or fewer residues of amino acids, while polypeptides
is used for peptides with moreamino acid residues. Although the point of transition
from polypeptide to protein is not well defined, proteins are normally considered to
have at least 100 residues (Mr>10,000) and this criterion will be followed within
the chapter.
In wines, peptides are the least known nitrogen compounds, in spite of the fact
that they are involved in diverse properties such as tensioactivity (Gonz ́alez-Llano
et al. 2004), sensorial activity (Desportes et al. 2001) and antihypertensive activity
(Pozo-Bay ́on et al. 2005), among others. Also they can act as nutrients for yeasts
M.V. Moreno-Arribas (B)
Instituto de Fermentaciones Industriales, CSIC. Juan de la Cierva 3, 28006 Madrid, Spain
e-mail: [email protected]
M.V. Moreno-Arribas, M.C. Polo (eds.),Wine Chemistry and Biochemistry,
DOI 10.1007/978-0-387-74118-58,©CSpringer Science+Business Media, LLC 2009
191