TABLE 3

Concentrations of volatile free fatty acids and volatile components identified in the four sourdoughs propagated under firm and liquid conditions for different times

Acid or componentaConcnb
MAIMAVLMAVFMBIMBVLMBVFMCIMCVLMCVFAIAVLAVF
VFFA
    Acetic acid514cd446d774bc863b824b1040a459d643c1178a283e953ab847b
    2-Methyl-propionic acid0.27bc0.40b0.33b0.20c0.40b0.38b0.20c0.36b0.52a0.08d0.51a0.31b
    Caproic acid2.37a0.96c2.82a2.56a1.38b2.69a2.03a1.86ab3.13a0.71c0.98c0.90c
VOC
    Acetaldehyde1.6E6c3.5E6b2.4E6bc1.8E6c4.7E6a4.8E6a3.5E6b6.1E6a4.7E6a1.7E6c3.0Eb5.7E6a
    Octanal3.7E5bc5.9E5b3.6E5bc5.6E5b6.9E5b4.0E5b2.9E5c7.1E5b5.4E5b5.0E5b1.2E6a4.1E5b
    Nonanal1.4E6c2.0E5b2.1E6b2.0E5b2.7E5b2.0E5b1.2E5c3.4E6ab2.2E5b2.5E5b4.0E5a2.3E5b
    Decanal1.2E5c4.3E5ab3.5E5b4.2E5ab5.0E5a5.1E5a2.1E5c4.9E5a5.1E5a3.8E5b4.9E5a3.7E5b
    2-Butenal (Z)3.6E4c5.0E4b3.6E4c4.3E4b5.2Ea4.5E4b4.5E4b4.6E4b3.8E4b3.1E4bc4.2E4b2.5E4c
    2-Pentenal4.4E5ab2.4E5bc3.7E5b3.0E5b2.6E5bc2.8E5b5.0E5a3.2E5b4.3E5ab4.1E5ab2.4E5bc2.0E5c
    3-Methyl-butanal1.7E5c6.0E5b1.4E5c1.5E5c2.1E6a1.0E6ab4.9E5bc2.0E6a1.3E6ab1.5E5c7.0E5b3.2E5bc
    Benzeneacetaldehyde2.9E5c1.5E6b1.0E5c2.6E5c4.1E6a7.7E5bc1.9E5c2.9E6ab9.3E5bc2.0E5c6.5E5bc1.9E5c
    Ethanol9.7E7b2.1E8a3.5E7c2.2E8a3.7E8a3.3E8a2.7E8a3.8E8a3.8E8a1.6E8a1.8E8a3.3E8a
    1-Butanol7.8E5b1.2E6ab9.3E5b9.6E5b1.7E6a1.7E6a8.3E5bc1.7E6a1.6E6a6.8E5c7.9E5b6.8E5c
    2-Butanol5.1E5a1.4E5a8.6E4b8.4E5a0.0E0c0.0E0c7.9E5a8.8E3bc2.6E4bc1.5E5a2.0E2c2.0E2c
    2-Methyl-1-propanol4.9E5c4.5E6b2.4E5c2.8E5c1.3E7a6.0E6b1.4E6bc9.8E6ab4.9E6b6.1E5bc3.6E6b4.5E6b
    3-Methyl-1-butanol7.1E6c8.3E7b3.2E6c2.3E6c2.1E8a1.1E8a1.8E7ab1.6E8a8.7E7b4.2E6c8.5E7b4.4E7ab
    2-Methyl-1-butanol1.4E6bc1.7E7ab7.7E5c6.6E5c4.0E7a2.3E7ab4.6E6b3.6E7a1.9E7ab4.5E5c9.8E6b4.1E6b
    3-Octanone1.1E5b1.3E5ab8.7E4bc1.0E5b1.1E5b8.1E4bc6.5E4c1.3E5ab9.7E4b1.0E5b1.8E5a7.5E4bc
    3-Methyl-2-butanone1.3E5b1.3E5b7.4E4bc1.5E5ab1.8E5a1.1E5b1.1E5b1.4E5b9.9E4bc1.2E5b1.3E5b5.6E4c
    Methyl acetate3.1E5bc7.0E5b6.3E5b3.7E5bc4.3E5b1.5E6a5.7E5b5.2E5b1.4E6a2.8E5c7.3E5b1.4E6a
    Methyl benzoate3.9E4b6.6E3c1.0E4bc8.8E4a1.5E4bc1.7E4bc3.1E4b1.6E4bc2.1E4bc4.2E4b5.5E3c9.1E3c
    Ethyl acetate9.6E7d1.8E8c1.1E8b1.6E8c2.9E8a3.1E8a1.1E8d2.8E8b2.3E8ab1.2E8d1.7E8c2.1E8b
    Propyl acetate1.2E5c9.0E5b1.4E5c3.8E5bc3.6E6a2.6E6a2.9E5bc3.0E6a1.2E6a1.4E5c8.8E5b1.4E6a
    2-Methyl-propyl acetate4.5E4c1.8E6a3.3E4c6.3E4c5.8E6a3.8E6a1.8E5b4.3E6a1.6E6a5.3E4c1.4E6a2.0E6a
    3-Methyl-butyl acetate4.5E5c2.5E7a2.9E5c3.1E5c5.3E7a4.0E7a1.9E6b4.2E7a2.0E7a2.5E5c3.0E7a1.3E7a
    2-Methyl-butyl acetate1.1E5bc4.3E6b8.6E4c9.7E4c1.3E7a9.2E6ab4.6E5bc9.7E6ab4.3E6b3.9E4c2.6E6b1.1E6b
    3-Methyl-butyl hexanoate3.1E3bc2.2E4b2.0E2c3.5E3bc7.9E4a3.4E4b0.0E0c7.6E4a2.6E4b9.4E2c6.5E3bc2.9E3bc
    2-Phenyl-ethyl acetate1.3E5d5.4E5bc3.9E3g9.4E4e1.3E6a2.0E5c3.7E4f7.3E5b3.7E5c7.5E4ef1.6E5d9.0E4e
    Carbon disulfide1.0E4cd1.6E4c2.8E4b3.0E4b1.1E4cd2.7E4b2.9E4b8.7E3d2.8E4b3.4E4b1.9E4c6.5E4a
    Dimethyl-trisulfide4.4E3c3.2E3cd4.8E3c7.6E3b4.8E3c9.1E3a7.6E3b4.8E3c8.1E3ab4.7E3c2.1E3d9.9E3a
    3-Methyl-furan2.0E5ab3.0E4d1.8E5b2.1E5ab5.3E3e2.6E4d1.6E5b5.1E3e8.8E4c2.4E5a1.9E4d4.9E4cd
    2-Hexyl-furan2.1E5b4.3E5a2.5E5b2.6E5b4.5E5a1.9E5b2.0E5b3.0E5b2.1E5b1.9E5bc4.7E5a1.4E5c
    Diethyl-ether4.8E3c4.5E4ab2.2E4b5.9E3c5.6E4a6.0E4a3.8E4ab6.1E4a6.7E4a1.6E4bc5.5E4a6.5E4a
    Decane3.1E5cd9.6E5b2.3E5d4.6E5c8.1E5b3.0E5d2.3E5d4.2E5c3.4E5cd7.7E5b1.1E6a2.5E5d
    Nonadiene11.3E5b6.3E4d1.0E5bc1.6E5b4.6E4e1.2E5bc1.3E5b4.6E4e8.2E4c1.8E5ab1.4E5b3.0E5a
    Nonadiene21.5E5b6.5E4d1.2E5c1.7E5bc5.0E4d1.4E5b1.5E5b5.3E4d1.0E5c2.0E5ab1.4E5b3.1E5a
    Ethyl,3-methyl-benzene1.5E5b8.3E4c9.5E4c2.2E5a8.7E4c1.6E5b1.4E5b1.1E5bc1.1E5bc1.6E5b8.8E4c1.1E5bc
    1-Methyl,2-ethyl-benzene2.1E5ab1.1E5b1.1E5b3.5E5a9.9E4c1.7E5b2.0E5ab1.3E5b1.4E5b2.2E5ab1.2E5b2.1E5ab
    1,2,3-Trimethyl-benzene2.1E5b1.3E5d1.4E5cd2.9E5a1.4E5cd2.3E5b2.1E5b1.8E5bc1.6E5c2.2E5b1.3E5d1.6E5c
    1,3,5-Trimethyl-benzene7.4E5b4.1E5c4.5E5c1.2E6a3.7E5c7.2E5b7.3E5b4.9E5c5.5E5bc8.1E5b4.6E5c5.8E5bc
    1,2,4-Trimethyl-benzene2.9E5b1.7E5bc1.9E5bc4.5E5a1.5E5c2.6E5b2.8E5b1.9E5bc2.3E5b3.0E5b2.0E5b2.2E5b
    Naphtalene7.2E5c8.1E5bc9.4E5bc7.4E5c1.1E6b1.0E6b6.0E5c1.4E6a1.5E6a1.1E6b1.3E6ab1.5E6a
    Alpha-pinene6.3E4d1.0E5b7.2E4c8.0E4c9.6E4bc6.6E4d7.1E4c1.5E5a7.6E4c7.5E4c1.6E5a6.6E4d
    Camphene7.1E4e7.6E4e1.1E5cd8.0E4e8.7E4e1.3E5cd7.4E4e1.0E5d1.1E5d4.0E5a1.9E5c2.8E5b
    Beta-pinene5.4E4cd8.0E4c4.7E4d8.6E4c1.2E5ab1.3E5a7.8E4c1.0E5b1.2E5ab5.7E4cd8.3E4c4.1E4d
    Beta-myrcene3.2E5a1.9E5c2.5E5b3.3E5a2.4E5b3.2E5a3.2E5a2.4E5b3.0E5a2.2E5b1.7E5c2.4E5b
    Delta-carene2.8E4c4.4E4b6.3E4ab3.1E4bc4.8E4b7.1E4a2.6E4c7.5E4a5.6E4ab2.9E4c3.4E4bc4.2E4b
    p-Cymene3.1E5c2.9E5d5.1E5a3.1E5c3.0E5d4.4E5b2.6E5d3.6E5c4.9E5b2.9E5d4.6E5b5.3E5a
    1(1-methyl-1-ethenyl)-4-methyl-benzene6.1E4c5.5E4cd8.8E4a5.8E4cd6.5E4c7.6E4b5.0E4d8.5E4ab7.9E4b4.9E4d9.0E4a9.3E4a
  • a Compounds that, based on the literature (4447), may have an impact on the aroma of sourdough baked goods are in boldface.

  • b VFFA are reported in ppm and VOC in arbitrary units of area. Only VOC that showed variation (P ≤ 0.05) between samples are reported. The ingredients and technological parameters used for daily sourdough backslopping are reported in Table 1. Times were as follows: 1 (I) and 28 (V) days. The data are the means of three independent experiments, and values in the same row followed by different lowercase letters (a to g) differ significantly (P ≤ 0.05).