In this article:

The article reports on experiments that have shown a properly prepared extract of vine ash is suitable for dipping sultana, and is almost as satisfactory in regards to quality and drying rate as a potash solution of the same density.

Vine Ash in Dipping Sultanas

1940, Journal of the Council for Scientific and Industrial Research, vol 13, pages 181 – 182

csiro 1940-1

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