The content of extractives of Norway spruce (Picea abies (L.) Karst.), silver fir (Abies alba Mill.) and Scots pine (Pinus sylvestris L.) twigs was investigated in distillates (spirits) and Soxhlet extracts of twigs. The effect of two growth periods on the amount of extractives was examined. For distillation, we used apple raw spirit, and for Soxhlet extraction methanol, differently concentrated ethanol and raw spirit. The crude extracts were purified with diethyl ether to separate the nonpolar fraction from the polar one. The amount of total extractives was measured gravimetrically in the samples. UV-Vis spectrophotometric analysis measured the content of total phenols colorimetrically. The content of vitamins, i.e. retinol, ascorbic acid and tocopherol, was determined by high-performance liquid chromatography (HPLC). The results showed that the twigs of all the studied tree species contain more total extractives and phenols in the autumn than in the spring. Spruce twigs contained the most extractives and firs the least. The quantities of extractives were significantly lower in the distillates than in the extracts. HPLC analysis showed that the vitamins in the conifer twigs are more present in the spring. Most ascorbic acid contained spruce and pine samples. Retinol was highest in firs in autumn and pine in spring. We did not detect tocopherol in any sample. We have shown that by using conifer twigs in spirits, part of the tree tissue extractives is pre-distilled into potable spirits.
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