Tackling the future challenges of Organic Animal Husbandry - vTI

RAHMANN G & GODINHO D (Ed.) (2012): Tackling the Future Challenges of Organic Animal Husbandry.
Proceedings of the 2 nd OAHC, Hamburg/Trenthorst, Germany, Sep 12-14, 2012
Table 1. Means of physico-chemical parameters during the ripening period depending on
the production system organic (Org) or conventional (Conv).
pH Dry extract Fat Fat acidity Ash
Month Org. Conv. Org. Conv. Org. Conv. Org. Conv. Org. Conv.
0 5,22 a 5,31 b 56,58 b 54,65 a 53,01 a 52,57 a 0,68 b 0,48 a 3,19 a 3,17 a
1 5,12 a 5,10 a 60,95 b 59,75 a 53,43 a 51,08 a 0,92 b 0,57 a 3,96 a 3,81 a
2 5,06 a 4,96 a 61,92 a 61,01 a 53,57 a 53,98 a 1,10 b 0,82 a 4,20 b 3,96 a
3 5,11 a 5,18 a 63,97 a 62,32 a 54,75 a 53,86 a 1,40 b 0,92 a 4,26 b 4,07 a
a Different type in the same row shows statistically significant differences for each parameter due to the production
system.
Freshly elaborated organic cheeses showed a significantly higher hardness (WBSF) (Table 2) related
to their lower dry extract, since the higher the moisture of the cheese, the lower the hardness,
fracturability, chewiness and gumminess (Pinho et al., 2004). As ripening progressed, the values for
WBSF increased due to the decrease in moisture, because water acts as a plasticiser in the protein
matrix, making it less elastic and more susceptible to fracture upon compression (Fox et al., 2000).
Water molecules are bound in the three-dimensional protein matrix and weaken the structure of the
network. Since moisture evolution was similar under both production techniques, and since in medium-matured
cheeses this effect predominates over others such as proteolysis, at the end of the
period considered the cheeses from both systems did not show statistically significant differences as
regards this parameter.
Table 2. Means of textural and colour parameters during the ripening period depending on
the production system organic (Org) or conventional (Conv).
L* a* b* WBSF
Month Org. Conv. Org. Conv. Org. Conv. Org. Conv.
0 93,03 a 93,57 a -0,77 a -0,67 a 16,30 b 13,23 a 4,15 b 3,59 a
1 86,39 a 89,22 b -0,77 a -0,74 a 23,97 b 19,26 a 4,43 b 3,17 a
2 86,78 a 89,71 b -0,98 a -0,93 a 23,32 b 18,65 a 3,82 b 3,11 a
3 87,41 a 89,64 b -0,88 a -1,06 a 22,34 b 18,54 a 4,41 a 4,32 a
a Different type in the same row shows statistically significant differences for each parameter due to the production
system.
Regarding instrumental colour, at the beginning of the ripening period, organic cheeses had a more
intense yellow colour. This observation could be related to the composition of the starting organic
origin of the cheese, which –as reported previously (Revilla et al., 2009), was more enriched in unsaturated
fats, which are characterized by a yellower colour. However, it could also be due to the
greater inclusion of green pasture in the diet of the organically raised sheep, which could afford
compounds such as carotenes or hitherto unknown elements (Priolo et al., 2003), leading the cheese
to become more yellow. The differences in the b* parameter increased during the ripening period,
and as from the first month of ripening the organic cheeses were also significantly darker, with a
lower L* value. Colour changes are due to the processes that occur during ripening, such as the loss
of moisture, proteolysis and lipolysis (Saldo et al., 2002), which seem to be more intense in organically
produced cheeses, as observed in the physico-chemical parameters.
References
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