TABLE 3.
Volatile compound | Possible source | Mean concentration in cheese (μg/g)a
|
||||
---|---|---|---|---|---|---|
Culture 1 | Culture 2 | Culture 3 | With KG | Without KG | ||
Alcohols | ||||||
4-Methyl-2-pentanol | Ketones | 0.06 (0.07) | 0.32 (0.32) | 0.11 (0.05) | 0.20 (0.27) | 0.13 (0.16) |
3-Methyl-1-butanol | Leu | 3.73 (3.44) | 3.01 (2.15) | 3.24 (2.60) | 3.30 (2.68) | 3.35 (2.63) |
2-Methyl-1-propanol | Val | 0.32 (0.59) | 0.06 (0.08) | 0.04 (0.05) | 0.23 (0.48) | 0.06 (0.07) |
1-Pentanol | Unknown | 0.06 (0.08) | 0.34 (0.40) | 0.05 (0.05) | 0.27A (0.33) | 0.03B (0.05) |
2-Heptanol | Unknown | 0.05 (0.06) | 0.01 (0.02) | 0.02 (0.03) | 0.03 (0.05) | 0.02 (0.04) |
1-Hexanol | Unknown | 0.44 (0.21) | 0.60 (0.78) | 0.16 (0.09) | 0.58 (0.58) | 0.23 (0.28) |
1-Octen-3-ol | Fatty acids | 0.11X (0.11) | 0.81Y (0.60) | 0.05X (0.03) | 0.43 (0.51) | 0.22 (0.48) |
1-Heptanol | Unknown | 0.01 (0.02) | 0.01 (0.02) | 0.02 (0.02) | 0.01 (0.02) | 0.02 (0.03) |
2-Ethyl-1-hexanol | Fatty acids | 0.36X (0.47) | 2.38Y (1.82) | 0.06X (0.04) | 1.27 (2.03) | 0.59 (0.53) |
2,3-Butanediol | Pyruvate | 0.14 (0.28) | 0.78 (1.55) | 0.04 (0.09) | 0.10 (0.23) | 0.55 (1.26) |
2-Phenethyl alcohol | Phe | 3.77 (2.83) | 3.22 (1.51) | 2.10 (0.22) | 3.03 (2.35) | 3.03 (1.36) |
Phenol | Tyr | 0.94 (0.72) | 1.46 (1.43) | 0.27 (0.15) | 0.54 (0.68) | 1.24 (1.17) |
Ketones | ||||||
2-Heptanone | Fatty acids | 0.41AB (0.31) | 0.52A (0.08) | 0.19B(0.04) | 0.30 (0.13) | 0.45 (0.28) |
3-Hydroxy-2-butanone | Pyruvate | 0.64X (0.22) | 1.41Y(0.71) | 0.61X (0.29) | 1.14A (0.67) | 0.64B (0.33) |
2-Nonanone | Fatty acids | 0.39 (0.30) | 0.82 (0.52) | 0.17 (0.22) | 0.37 (0.53) | 0.54 (0.34) |
4-Methyl-3-penten-2-one | Fatty acids | 1.03 (0.83) | 0.85 (0.43) | 0.47 (0.05) | 0.90 (0.69) | 0.66 (0.37) |
4-Hydroxy-4-methyl-2-pentanone | Fatty acids | 0.13 (0.17) | 0.50 (0.88) | 0.19 (0.04) | 0.45 (0.67) | 0.10 (0.11) |
2-Undecanone | Fatty acids | 0.01 (0.01) | 0.01 (0.02) | 0.03 (0.03) | 0.02 (0.02) | 0.01 (0.03) |
8-Nonen-2-one | Fatty acids | 0.01 (0.02) | ND | 0.01 (0.03) | ND | 0.02 (0.03) |
Acetophenone | Phe | 0.52 (0.85) | 1.36 (1.26) | 0.06 (0.02) | 0.60 (1.23) | 0.70 (0.76) |
Aldehydes | ||||||
Nonanal | Fatty acids | 0.44X (0.33) | 1.03Y (0.45) | 0.23X (0.13) | 0.52 (0.48) | 0.62 (0.49) |
Decanal | Unknown | 0.10 (0.15) | 0.43 (0.82) | 0.03 (0.05) | 0.08 (0.12) | 0.29 (0.67) |
Hexadecanal | Unknown | 0.42 (0.48) | 0.55 (0.31) | 0.22 (0.20) | 0.27 (0.23) | 0.52 (0.42) |
Octadecanal | Unknown | 1.45 (2.29) | 1.71 (1.99) | 0.06 (0.08) | 1.23 (1.72) | 0.91 (1.94) |
Benzaldehyde | Phe | 0.24X (0.14) | 0.94Y (0.52) | 0.06X (0.02) | 0.29 (0.21) | 0.54 (0.66) |
Fatty acids | ||||||
Acetic acid | Pyruvate | 1.47X (0.56) | 3.78Y (0.95) | 0.38Z (0.34) | 2.17 (1.78) | 1.59 (1.49) |
Butanoic acid | Fatty acids | 0.75 (0.91) | 1.48 (0.70) | 0.19 (0.17) | 0.73 (0.92) | 1.06 (1.07) |
Hexanoic acid | Fatty acids | 0.26 (0.33) | 0.32 (0.19) | 0.37 (0.07) | 0.34 (0.14) | 0.68 (0.95) |
2-Ethylhexanoic acid | Unknown | 0.20 (0.40) | 0.17 (0.23) | 0.11 (0.13) | 0.21 (0.22) | 0.11 (0.20) |
Octanoic acid | Fatty acids | 0.13 (0.21) | 0.45 (0.33) | 0.20 (0.15) | 0.35 (0.22) | 0.17 (0.28) |
3-Methyl butanoic acid | Leu | 0.49 (0.88) | 0.36 (0.45) | 0.11 (0.15) | 0.16 (0.21) | 0.48 (0.75) |
Pentanoic acid | Fatty acids | 0.14A (0.22) | 1.26B (1.08) | 0.05A (0.04) | 0.59 (0.87) | 0.38 (0.82) |
Sulfur | ||||||
Dimethyl sulfide | Met | 0.68AB (0.32) | 1.36A (0.68) | 0.37B (0.11) | 0.66 (0.68) | 0.94 (0.50) |
Treatments: culture 1, cheeses manufactured with Lactococcus lactis D11 alone; culture 2, cheeses manufactured with D11 plus L. casei 334e; culture 3, cheeses manufactured with D11 plus the L. casei HADH strain; with KG, cheeses manufactured with 2% KG added; without KG, cheeses manufactured without added KG. Values shown in the same row with different superscript letters are significantly different at P values of <0.05 (X, Y, Z) or <0.1 (A, B) from other values for the same treatment group (culture or KG). Values in parentheses denote ± standard errors (n = 3 for culture treatment and n = 2 for KG treatment). ND, not detected.