Pinho Olivia, Pintado Ana I E, Gomes Ana M P, Pintado M Manuela E, Malcata F Xavier, Ferreira Isabel M P L V O
REQUIMTE, Serviço de Bromatologia, Faculdade de Farmácia, Universidade do Porto, R Aníbal Cunha 164, 4050-047 Porto, Portugal.
J Food Prot. 2004 Dec;67(12):2779-85. doi: 10.4315/0362-028x-67.12.2779.
Changes in the microbiological, physicochemical, and biochemical characteristics of Terrincho cheese as represented by native microflora, pH, water activity, soluble nitrogen fractions, free amino acids, and biogenic amines (e.g., ethylamine, dimethylamine, tryptamine, phenylethylamine, putrescine, cadaverine, histamine, tyramine, cystamine, and spermine) during ripening were monitored. Terrincho is a traditional Portuguese cheese manufactured from raw ewe's milk. The main groups of microorganisms (lactococci, lactobacilli, enterococci, pseudomonads, staphylococci, coliforms, yeasts, and molds) were determined following conventional microbiological procedures. Free amino acids and biogenic amines were determined by reverse-phase high-performance liquid chromatography, following extraction from the cheese matrix and derivatization with dabsyl chloride. The total content of free amino acids ranged from 1,730 mg/kg of dry matter at the beginning of the ripening stage to 5,180 mg/kg of dry matter by day 60 of ripening; such an increase was highly correlated with the increase of water-soluble nitrogen in total nitrogen, 12% trichloroacetic acid-soluble nitrogen in total nitrogen, and 5% phosphotungstic acid-soluble nitrogen in total nitrogen throughout ripening. Histamine was consistently present at very low levels, whereas putrescine, cadaverine, and tryptamine were the dominant biogenic amines and increased in concentration during ripening. Ethylamine, tryptamine, phenylethylamine, and cystamine reached maxima by 30 days of ripening and decreased thereafter. Significant correlations between amino acid precursors and corresponding biogenic amines, as well as between biogenic amines and microbial viable numbers, were observed.
监测了特林乔奶酪在成熟过程中微生物学、物理化学和生物化学特性的变化，这些特性由本地微生物群落、pH值、水分活度、可溶性氮组分、游离氨基酸和生物胺（如乙胺、二甲胺、色胺、苯乙胺、腐胺、尸胺、组胺、酪胺、胱胺和精胺）来体现。特林乔是一种用生羊奶制成的传统葡萄牙奶酪。按照传统微生物学程序确定了主要微生物类别（乳酸球菌、乳酸杆菌、肠球菌、假单胞菌、葡萄球菌、大肠菌群、酵母和霉菌）。从奶酪基质中提取并经丹磺酰氯衍生化后，采用反相高效液相色谱法测定游离氨基酸和生物胺。游离氨基酸的总含量在成熟初期为每千克干物质1730毫克，到成熟第60天时增至每千克干物质5180毫克；这种增加与整个成熟过程中总氮中水溶性氮、总氮中12%三氯乙酸可溶性氮以及总氮中5%磷钨酸可溶性氮的增加高度相关。组胺始终以极低水平存在，而腐胺、尸胺和色胺是主要的生物胺，在成熟过程中浓度增加。乙胺、色胺、苯乙胺和胱胺在成熟30天时达到最大值，此后下降。观察到氨基酸前体与相应生物胺之间以及生物胺与微生物活菌数之间存在显著相关性。
