Published online by Cambridge University Press: 27 March 2009
1. The average electrode potentials of laboratory silages of various types have been measured.
2. The electrode potentials of ordinary and molassed silages tended to assume values of the order of –0·05 to –0·10 V. from about the third day; the pH of these silages lay in the range pH 4·0 to 5·5.
3. In a number of instances secondary increases of electrode potential were observed, frequently in association with secondary deterioration.
4. The electrode potential of silage prepared with hydrochloric acid and of pH 3·4 remained steady around +0·18 V.; the potential of silage prepared with formic acid and of pH 3·9 was about + 0·35 V. initially but declined towards + 0·23 V. at 35 days.
5. Curves for the ‘pure’ carotene content of laboratory silages displayed minima during the early stages of fermentation except in the case of formic acid silage.