Thiamine Dilauryl Sulfate Research Articles

Growth Inhibition of Film-Forming Yeasts During Production of Ume-Zuke (Pickled Japanese Apricots) by an Antimicrobial Fraction Extracted from Paprika Seeds.

Paprika extract (50 to 100 μg/ml) obtained by suspending ground paprika seeds in water, adding ethanol (50%, v/v), and then filtering the suspension, inhibited the growth of film-forming yeasts (Kloeckera, Pichia, Debaryomyces, and Candida species) isolated during the production of ume-zuke, a processed food product made by salting Japanese apricots (Prunus mume). The antimicrobial activity of the extract towards Pichia anomala was influenced by the initial number of yeast cells, as well as the temperature, pH, and sodium chloride concentration of the culture medium (ume vinegar). The inhibitory effect was cumulatively enhanced, although not synergistically, when the paprika seed extract was used in combination with either SO2, sorbic acid, thiamine dilauryl sulfate, or acetic acid. The antimicrobial activity of the extract was not influenced by the vinegar components. The extract proved to be very effective as a preservative to prevent the contamination and spoilage of ume-zuke by film-forming yeasts.

On the Useful Effect of Lauryl-compounds as the Sake Preservatives

Antimicrobial effects of nine kinds of lauryl-compounds on the growth of Hiochi bacteria in sake were investigated as following: sodium lauryl sulfate, thiamine dilauryl sulfate, laurylamine, sodium lauryl benzenesulfonate, methyl laurate, ethyl laurate, lauryl chloride, sodium laurate, p-hydroxybenzoic acid lauryl ester.1. Both laurylamine and ethyl laurate, which had the strongest antihiochi activity among the nine drugs, inhibited the growth of Hiochi bacteria at the concentration 4 to 6ppm in diluted sake (alc. 14%) and had 40 to 50 times as strong antimicrobial activity as salicylic acid.2. Laurylamine had the highest solubility in sake among the nine drugs, and no increase in turbidity of the sake by addition of laurylamine (10ppm) could be detected.3. From the result of sensory test, laurylamine did not show any bad influence on the qualities of sake at the concentration 3 to 4ppm. On the other hand, ethyl laurate showed a different flavor in sake at the same concentration. It was concluded, thus, that the laurylamine seemed to be one of the most favorable preservatives for sake among the nine drugs.