Figures (4)  Tables (2)

    • Figure 1. 

      The increase or decrease rates of phytochemical compounds (compared with fresh group) in MH-and HPP-processed NFC spine grape juice. (a) Anthocyanins, (b) Flavonols, (c) Flavan-3-ols, (d) Phenolic acids, (e) Stilbenes. # indicate compounds only detected in the MH group.

    • Figure 2. 

      Multivariate analysis based on metabolomics data. (a) Venn plot for MS1 feature quantities in MH, HPP, and fresh, (b) PCA score plot, (c) Heatmap, (d) OPLS-DA model.

    • Figure 3. 

      The putative annotated markers between MH- and HPP-processed NFC spine grape juice. The left are the box-plots, and the right are the chemical structures of individual biomarkers. (a) Malvidin-3-O-glucoside, (b) Malvidin-3,5-di-O-glucoside, (c) Quercetin-3-O-glucuronide, (d) Quercitrin-3-O-rhamnoside, (e) Ferulic acid, (f) Caffeic acid, (g) Catechin, (h) Procyanidin B1, (i) Procyanidin B2, (j) Glu-Val-Phe, (k) Leu-Leu-Tyr. Procyanidin B1, procyanidin B2 and Leu-Leu-Tyr only detected in the MH group.

    • Figure 4. 

      Changes of annotated markers during storage. (a) Malvidin-3-O-glucoside, (b) Malvidin-3,5-di-O-glucoside, (c) Quercetin-3-O-glucuronide, (d) Quercitrin-3-O-rhamnoside, (e) Ferulic acid, (f) Caffeic acid, (g) Catechin, (h) Procyanidin B1, (i) Procyanidin B2, (j) Glu-Val-Phe, (k) Leu-Leu-Tyr. The solid and dotted lines represent different grape varieties. Different letters indicated significant difference between storage day.

    • VarietyTCZQ
      Processing methodFreshMHHPPFreshMHHPP
      pH3.45 ± 0.02a3.45 ± 0.04a3.60 ± 0.03b3.71 ± 0.03b3.57 ± 0.04c3.84 ± 0.03a
      TSS (%)14.60 ± 0.10a14.43 ± 0.06a14.50 ± 0.10a14.27 ± 0.38a14.57 ± 0.15a14.27 ± 0.12a
      Glucose (g/L)71.59 ± 2.03a70.43 ± 4.76a68.14 ± 2.83a71.66 ± 1.69a68.85 ± 2.32a68.86 ± 1.71a
      Fructose (g/L)72.79 ± 2.36a71.07 ± 3.23a71.90 ± 2.56a74.17 ± 2.93a70.07 ± 2.53a70.21 ± 1.87a
      Tartaric acid (mg/L)4,822.08 ± 285.58a4,925.37 ± 380.44a2,810.97 ± 50.57b4,262.18 ± 141.90a4,446.3 ± 438.02a2,791.82 ± 231.73b
      Malic acid (mg/L)472.13 ± 20.71a456.06 ± 5.99a343.91 ± 30.30b668.52 ± 12.53a536.71 ± 31.26b498.85 ± 19.84c
      Critic acid (mg/L)128.07 ± 2.72a125.07 ± 2.29a126.05 ± 2.07a212.59 ± 2.76a217.04 ± 3.51a211.67 ± 2.04a
      TPC (mg/L)593.42 ± 29.22c983.12 ± 58.29a671.82 ± 14.00b611.68 ± 25.68c1031.53 ± 58.94a726.75 ± 24.23b
      TAC (mg/L)156.87 ± 4.91b299.77 ± 4.59a179.92 ± 6.01b115.74 ± 10.81b269.08 ± 6.63a134.40 ± 5.01b
      L25.64 ± 0.6c28.75 ± 0.66a26.59 ± 0.46b24.36 ± 0.21c29.27 ± 1.02a27.56 ± 0.61b
      a6.03 ± 0.23b9.57 ± 0.42a6.34 ± 0.75b3.98 ± 0.14c8.28 ± 0.18b4.24 ± 0.27b
      b−2.46 ± 0.17b−2.30 ± 0.14b−1.94 ± 0.08a−2.47 ± 0.09a−2.34 ± 0.13a−2.28 ± 0.13a

      Table 1. 

      The traditional index of MH- and HPP-processed NFC spine grape juice.

    • IDMetabolitesFormulaAdduct typeRt (min)Average m/zReference m/zppmp-valuelog2Fold changeBeing identified in targeted analysislog2Fold change (in storage)
      14109Malvidin-3,5-O-diglucosideC29H34O17[M+H]+3.798655.1869655.18690.000.0121.8√> 1.0
      10725Malvidin-3-O-glucosideC23H25O12[M]+5.766493.1338493.13350.570.0122.6√> 1.0
      10254Quercetin-3-O-glucuronideC21H18O13[M+H]+6.829479.0808479.082−2.540.002.2√< 1.0
      9283Quercitrin-3-O-rhamnosideC21H20O11[M+H]+7.707449.1088449.107792.150.001.2√> 1.0
      1216Caffeic acidC9H8O4[M+H]+3.373181.0494181.0495−0.610.002.0√> 1.0
      1560Ferulic acidC10H10O4[M+H]+4.708195.06523195.06434.760.001.3√< 1.0
      4046CatechinC15H14O6[M+H]+4.061291.086291.086−0.100.003.9√> 1.0
      12875Procyanidin B1C30H26O12[M+H]+3.530579.159579.14970.38−−√> 1.0
      12873Procyanidin B2C30H26O12[M+H]+4.515579.1506579.14970.16−−√> 1.0
      7503Glu-Val-PheC19H27N3O6[M+H]+5.265394.1969394.1971−0.610.0153.1×> 1.0
      7954Leu-Leu-TyrC21H33N3O5[M+H]+6.293408.2488408.2493−1.35−−×> 1.0
      Procyanidin B1, procyanidin B2 and Leu-Leu-Tyr only detected in the MH group.

      Table 2. 

      The putative annotated markers of MH- and HPP-processed NFC spine grape juice.