2.1. Pine Needle Fermentation

Pine needles used in this experiment were collected from Pinus densiflora, a native to Bonghwa, Gyeongbuk, Korea. The collected needles were washed, air-dried, and stored at 4 °C until fermentation. The pine needles were analyzed for their nutrient composition using AOAC procedures [18] (Table 1). For fermentation, the pine needles were chopped to 1 cm in size and mixed with water and sugar in a ratio of 1:1:0.6 on weight basis and then spontaneously fermented in an earthen pot (120 L) with the covered lid at room temperature for 6 months. The pine needles were then removed, and the remaining solution was aged in the same pot at room temperature for another 6 months. After aging, this solution was termed as a fermented pine needle extract (FPNE). The FPNE was then transferred to a stainless-steel beverage tank and stored at 4–8 °C until further use.

The nutrient composition of pine needles ¹.

¹ The results are presented as mean ± standard deviation. Percentages (%) are expressed as dry matter basis.