Table 4.
Experimental factors for the two-level fractional factorial experimental (one-half).
| Factor | Description | Low Level | High Level |
|---|---|---|---|
| A | pH a | 3.00 | 3.80 |
| B | Ethanol (%) b | 13.5 | 14.8 |
| C | Sugar (g/L) c | 0.16 | 8.00 |
| D | Temperature (°C) | 10 | 20 |
| E | Agitation | No | Yes |
a Wine samples were measured for pH by using a Mettler Toledo T50 Autotitrator (Port Melbourne, VIC, Australia). b The ethanol concentration was determined with the Anton Paar Alcolyzer Wine ME and DMA 4500M (North Ryde, NSW, Australia). c The sugar content were determined via Chemwell® 2910 Automated EIA and Chemistry Analyser (Awareness Technology, Palm City, FL, USA) with the Megazyme K-FRUGL test kits (Chicago, Illinois, USA).