Biogenic amines content of the Egyptian domiati cheese in relation to chemical composition and ripening indices

Market Domiati cheese samples representing Baramili and Istamboli types were analysed for the presence and quantity of biogenic amines (BAs).The total BAs content as an average ±SE was 27.36±9.16 mg/100g of Baramilicheese  including tyramine (13.03 mg/100g) , cadaverine (8.01 mg/100g) , putrescine (3.35 mg/100g) and histamine (2.81 mg/100g) with the percentages of 47.62 , 29.28 , 12.24 and 10.27 from the total BAs respectively .Tyramine (4.88 mg/100g) was the most prevalent amine in Istambolicheese  representing 57.68% of the total BAs detected (8.46 mg/100 g) .This was followed by quantites of 1.69 , 1.38 and 0.44 mg/100g for histamine , cadaverine and putrescine in order with the corresponding percentages  of 19.98 , 16.31 and 5.20 from the total .The BAs spermidine and spermine were detected in both cheese  types in quantities less than 0.10 mg/100g .All cheese  Samples were analysed for acidity , pH , moisture , fat , salt , protein , soluble nitrogen (SN) , formol ripening index (FRI) and Shilovichripening index (SRI) .The statistical analysis revealed that histamine (Him) , tyramine (Tym) , putrescine (Put) and cadaverine (Cad) as well as total BAs (TBAs) positively correlated with protein content and negatively correlated with SN / TN content .Tym had the maximum r values of +0.776 (P≤0.01) and -0.729 (P≤0.05) respectively. A highly significant correlations were recorded between spermidine (Spd) and spermine (Spm) from one side and acidily and pH from the other side . Tym , the most prevalent amine in cheese  and the TBAs negatively correlated with SN / TN , FRI , SRI , acidity , moisture and fat content one dry matter basis . Finally Him ,Tym , Spd and Spm negatively correlated (P≥0.05) with salt / moisture , whereas the rest of BAs showed insignificant positive correlation in this respect .