Red and white grape musts were enriched with 7-hydroxymatairesinol (HMR), which is the main lignan contained in spruce knots. Lignan enrichment was achieved by adding a spruce knot ethanol extract. Enriched musts were stored for 12 months and during storage must samples were periodically analyzed for HMR and alpha-conidendrin content, antioxidant activity, total polyphenols, and anti-mutagenicity. The data were statistically evaluated in order to determine the influence of grape type, quantity of added lignan extracts, addition of sugar, method of preservation and storage time on the quantity of lignans added, antioxidant activity, total polyphenols, and anti-mutagenicity. Lignan content was significantly influenced by the addition of lignan extracts. After storage, lignan content had changed only moderately and the added lignans were stable in the stored musts. Total polyphenol content and antioxidant activity of grape musts were significantly increased by the type of must grape and by thermomaceration. Thermomacerated red musts exhibited higher anti-mutagenicity compared to thermomacerated white musts, independent of lignan addition.