Chemical preservation of partially dried potato pulp

Mechanically dehydrated potato pulp containing up to 50% dry matter was stored, without visible deterioration, for up to 25 weeks after treatment with at least 0·3% of propionic acid. Wetter pulps required more acid for satisfactory preservation. Thorough mixing was important if maximum storage periods were to be achieved. Ammonia was less satisfactory as a preservative. No visible deterioration occurred while ammonia vapour was present, but bacterial growth was still found even after the addition of about 0·7% ammonia to pulp containing 40–45% dry matter.