Effect of different storage temperatures and periods on biogenic amines formation in ras cheese

الملخص EN

Biogenic amines are formed in dairy products during storage and / or ripening process, as a result of degradation of proteins by proteolysis.

The resulted free amino acids act as precursors for their formation.

Therefore, the effect of storage temperatures (7, 22 and 32°C) and periods (7, 30, then every 15 days for 120 days) on the levels of biogenic amines in Ras cheese were studied.

The overall results indicated that the levels of biogenic amines increased with the increasing temperatures and ripening periods.

Also, the results pointed out that the increasing values of biogenic amines formed during ripening of Ras cheese varied at different storage temperatures.

Histamine increased slowly from 1.73 mg / 100 g at zero time to reach 32.57, 76.70 and 175.30 mg / 100 g at 7°C, 22°C and 32°C, respectively, by the end of storage (120 days).

Regarding tyramine, gradual increase was monitored from 0.03 mg / 100 g to reach 1.69, 3.26 and 10.95 mg / 100 g at the same storage temperatures, respectively, by the end of storage periods.

Tryptamine increased gradually from 0.45 mg / 100 g to reach 5.12, 7.66 and 15.47 mg / 100 g at the specified temperatures, respectively, by the end of storage periods.

Cadaverine increased gradually from 1.47 mg / 100 g to reach 7.05, 17.22 and 44.18 mg / 100 g at the same storage temperatures, respectively, by the end of storage periods.

Putrescine was found to increase slowly from 0.58 mg / 100 g to reach 3.91, 11.27 and 24.59 mg / 100 g at the specified temperatures, respectively, by the end of storage periods.

Histamine levels in Ras cheese reached the maximum permissible limits during ripening after 120, 60 and 30 days at 7°C, 22°C and 32°C, respectively, according to FDA guidelines (≤20 mg / 100 g).

Whereas, according to EC, Canadian and Australian and New Zealand guidelines (≤10 mg / 100 g), histamine contents in Ras cheese reached the unallowable limits after 90, 45 and 30 days at 7, 22 and 32°C, respectively.

The results also revealed that histamine reached toxic dose (75-200 mg / 100 g) after 105 days of storage at 22°C and after 75 days during storage at 32°C.

Also, the tyramine reached toxic dose (10-80 mg / 100 g) after 105 days during storage at 32°C.

The public health significance of biogenic amines and the sanitary measures recommended to produce safe cheese were discussed.