## 2 Materials and Methods
### Analysis of Berry Monoterpene Profiles  
The extractions of free and glycosylated monoterpenes from grapes were performed following the methods of [PERSON] et al. [22] and [PERSON] et al. [27] Briefly, 100 frozen grapes were randomly selected for each treatment in triplicate, immediately deseeded, destemmed, and powdered using an analytical mill (IKA, A 11, Staufen, Germany) with liquid nitrogen. After 4 h of maceration at 4 \({}^{\circ}\)C, the powdered tissue suspensions were centrifuged at 8000\(\times\)\(g\) for 15 min at 4 \({}^{\circ}\)C to obtain clear juice. Then, 5 mL clear juice mixed with 10 \(\upmu\)L 4-methyl-2-pentanol (as an internal standard) and 1 g NaCl were placed in a 20-mL vial for the analysis of free monoterpenes.  
To extract the glycosylated monoterpenes from the grapes, Cleanert PEP-SPE cartridges (200 mg/6 mL, Agela, Beijing, China) were activated successively with 10 mL methanol and 10 mL distilled water, after which 2 mL grape juice was passed through each cartridge. Then, the cartridges were washed with 5 mL pure water to remove low-molecular weight polar substances, followed by 5 mL dichloromethane to elute substances that might interfere with free aromatic compounds. Subsequently, the glycosylated monoterpenes were eluted with 20 mL methanol at a flow rate of 2 mL/min to ensure complete elution. The resulting methanol eluates were evaporated to dryness under a vacuum, and the residues rinsed with citric acid solution. Finally, the glycosylated fractions were liberated by enzymatic hydrolysis with 100 \(\upmu\)L AR 2000 enzyme (Rapidase, Seclin, France) for 16 h at 40 \({}^{\circ}\)C. The mixed solution after enzymatic hydrolysis (5 mL) was also used for the free-form monoterpene analysis using headspace solid-phase microextraction (HS-SPME)/GC-MS as described below.  
The modified HS-SPME was used for the monoterpene component analysis from grape extracts [22; 23]. Briefly, 5 mL of grape extract, 1.0 g of NaCl and 10 \(\upmu\)L of 4-methyl-2-pentanol (Aldrich, Milwaukee, WI, USA) were added to a 20-mL sample vial, and the sample bottle's polytetrafluoroethylene cap was immediately tightened. Then, the samples were equilibrated for 30 min at 40 \({}^{\circ}\)C and placed on a stirring platform with a heated magnet. A 50/30 \(\upmu\)SPME fiber (DVB/CAR/PDMS, Supelco, Bellefonte, PA, USA) was pre-activated at 250 \({}^{\circ}\)C and then inserted into the headspace of the sample vial to adsorb volatiles for 30 min at 40 \({}^{\circ}\)C under 500 rpm agitation conditions. Subsequently, the fiber was quickly inserted into the GC injection port for 8 min to desorb aroma volatiles. The aroma volatiles were analyzed using Agilent 6890 GC (Agilent Technologies, Santa Clara, CA, USA) and Agilent 5975 MS (Agilent Technologies) instrumentation fitted with a 60 m \(\times\) 0.25 mm HP-INNOWAX (J & W Scientific, Folsom, CA, USA) capillary column (0.25-\(\upmu\)m film thickness) with a flow rate of 1 mL/min helium (carrier gas). The operating temperatures of the MS inlet, ion source, and interface were 250 \({}^{\circ}\)C, 230 \({}^{\circ}\)C, and 280 \({}^{\circ}\)C, respectively. The temperature program of the column oven was as follows: hold at 50 \({}^{\circ}\)C for 1 min, increase to 220 \({}^{\circ}\)C at a rate of 3 \({}^{\circ}\)C/min, and then hold at 220 \({}^{\circ}\)C for 5 min. The C6-C24 series of n-alkane was used to calculate the retention indices under the same chromatographic conditions. Monoterpene profile identifications were based on comparisons of the retention indices with those of authentic standards and of mass spectra with those in the standard NIST 11 library. The quantifications of volatiles with reference standards were determined using the peak area ratio of the standard to internal standard vs. the reference standard concentration, and those without an available standard were determined using the standard with a similar carbon structure or atoms.