The malolactic fermentation requires monitoring just like the primary fermentation. This is done to asses the progress of the fermentation so the winemaker knows if any difficulty is occurring, and to insure that wine quality is being maintained. The monitoring focuses on analyzing the disappearance of malic acid in the wine as it gets converted to lactic acid.

A few different methods are available to analyze malic acid but most require some expensive equipment and are out of the range of the amateur winemaker. The analysis of choice for small producers is paper chromatography. Chromatography kits are available to buy and are very easy for the amateur winemaker to use. A special type of paper comes with the kit. The winemaker adds a couple drops of the wine to be analyzed near the bottom of the paper along with drops from acid standards for malic, lactic, and tartaric acids. The paper is then placed in a jar with the chromatography reagent. Over several hours the reagent will travel up the paper. The paper is removed and left to dry once the reagent nears the top. Several spots will appear where the acids present traveled along with the reagent up the length of the paper. Each type of acid will migrate a certain distance from the bottom, and the winemaker judges whether any spots corresponding to the distance that the malic acid standard travels also appear where the wine samples were placed on the paper. Once the malic acid spots for the wine samples no longer appear when the analysis is performed, the malolactic fermentation is considered complete. This analysis should be performed once or twice a week while the malolactic fermentation is occurring. More specific directions on running the analysis will be included with the kits. Precaution is required with this analysis as the reagent is considered a hazardous chemical. The test should be performed in a well ventilated area, as breathing the reagent fumes is not recommended.

Sensory evaluation should be performed on the wine during the malolactic fermentation in addition to the analysis of malic acid. The main concern the winemaker looks for when tasting the wine is the development of spoilage characters, particularly volatile acid development, as spoilage bacteria capable of performing a malolactic fermentation will usually produce excess amounts of this wine flaw.