ORIGINAL
RESEARCH Influence of ripening on proteolysis and lipolysis of
Murcia al Vino cheese
KHALID BOUTOIAL, YANILKA ALC
ANTARA, SILVIA ROVIRA,
V
ICTOR GARC
IA, EDUARDO FERRANDINI and MAR
IA BEL
EN
L
OPEZ*
Food Science and Technology Department, Faculty of Veterinary, Campus Mare Nostrum (CMN), University of
Murcia, campus de Espinardo, 30071, Murcia, Spain
The aim of this study was to evaluate the influence of five different manufacturers and two ripening
periods on the proteolysis and lipolysis patterns of Murcia al Vino goat cheese. The manufacturers
significantly affected the water activity (a
w
), pH, dry matter and fat content, several nitrogen
fractions: water soluble nitrogen (WSN), trichloroacetic acid (12% w/v) soluble nitrogen (TCASN)
and phosphotungstic acid (5% w/v) soluble nitrogen (PTASN); also the free amino acid (FAA) and
free fatty acid (FFA) contents, with the exception of C
4:0
,C
16:0
and C
18:0
. Different ripening
periods significantly affected the dry matter content, WSN and PTASN and all FAA, except serine.
Keywords Murcia al Vino Cheese, Cheese ripening, Lipolysis, Proteolysis.
INTRODUCTION
The province of Murcia, which is located in
southeastern Spain, has traditionally produced
artisanal goat milk cheeses, recognized by two
different Protected Designations of Origin:
‘Murcia Cheese’ and ‘Murcia al Vino cheese’.
Murcia al Vino cheese is manufactured with
goat’s milk from the Murciano-Granadina
breed. This variety is a rather fatty and
washed curd, pressed, but uncooked, semi-hard
cheese with a cylindrical shape and a smooth,
light rind, which is immersed twice in red
wine. The cheese has a white, creamy and
elastic paste. Its taste is pleasantly acidic and
slightly salty. It has a light aroma, is compact
when cut and has small holes. Its rind is
smooth, light and of a garnet red-ginger color
due to its immersion in red wine. Its size and
ripening period differ between manufacturers
although there is a legislated weight of 2 kg
and 1 kg and a minimum ripening period of
45 days. Together, production reached
345 747 kg in 2009, with the United States
importing 62.73% of the total production of
Murcia al Vino cheese during the same year
(Annual report 2009).
Cheese ripening is a very complex process,
which results in the development of the particular
flavour and texture cheese characteristics. The
most important biochemical reactions in cheese
ripening are proteolysis, lipolysis and glycolysis,
which largely result from the activity of milk
coagulant enzymes, starter lactic acid bacteria
(LAB) and non-starter LAB, together with
secondary cultures and exogenous enzymes.
Proteolysis is the most complex of the biochemi-
cal events that take place during cheese ripening
and is also important in the development of
flavour and texture (Fox et al. 1993). Proteolysis
comprises two phases: primary proteolysis,
which includes the hydrolysis of caseins
produced by the action of residual indigenous
proteinases of the coagulant used in cheesemak-
ing and secondary proteolysis, which is charac-
terized by the hydrolysis of the polypeptides and
peptides produced during primary proteolysis, as
a consequence of the action of starter bacteria,
microorganisms or enzymes, which produce
peptides and free amino acids (FAA). FAA are
precursors of the secondary catabolic reactions
that are responsible for the production of the
greatest part of volatile aromas during cheese
ripening (Abell an et al. 2012).
Many authors have evaluated the degree of
proteolysis in cheese by analyzing the nitrogen
content of different fractions: WSN, the TCASN
(12% w/v) and the PTASN (5% w/v) (B€ utikofer
*Author for
correspondence. E-mail:
mbelen@um.es
© 2013 Society of
Dairy Technology
366 Vol 66, No 3 August 2013 International Journal of Dairy Technology
doi: 10.1111/1471-0307.12024