Someone recently asked about grape extract in soap. If the questioner meant grape seed extract, would the answer be different? Grape seed extract is a common extract found in health food stores along with essential oils. Grape extract is obviously wine or juice, but grape seed oil or extract are not at all the same as wine or grape juice. Would the answer be the same for grape seed extract as for grape extract (wine) regarding kashrus?
One does not have to be concerned for grape seed extract.
Grape seed extract is generally permitted, for the following reasons:
1) According to the Shulchan Aruch, once the grape seeds have been completely dried (over a 12 month period), there is no longer a concern for stam yeinam. Many authorities hold that the drying processes of today (the seeds are generally meticulously dried before extraction) have the same halachic status.
2) The Chasam Sofer writes that the change of seed to oil, so that the final product bears no resemblance at all to the original, is sufficient to permit the final product (based on a ruling of Rabbeinu Yonah).
3) The Chelkas Yaakov writes that the oil and the wine have no connection, and therefore the oil is permitted.
See Yoreh De’ah 123:14-17 and Pischei Teshuvah 20.