Effect of a Bacterial Inoculant on the Fermentation of High Moisture Shelled and Ear Corn

Abstract
The effect of DM percent and bacterial inoculation of fermentation of shelled corn and ear corn was determined. Shelled corn at 76, 68, and 67% DM and ear corn at 79, 71, and 64% DM were treated with no inoculant (control), dry inoculant, or reconstituted inoculant at ensiling. Both inoculants contained Lactobacillus plantarum, L. brevis, and Pediococcus acidilactici. In addition, the dry inoculant contained a protease, amylase, and gumase, whereas the reconstituted inoculant contained amylase, gumase, and hemicellulase. Calculated inoculant application rate was 53 million cfu for dry and 264 cfu for reconstituted per kg of ensiled corn. Ground, treated shelled corn and ear corn (2.27 kg) were ensiled in plastic bags for 0, 1, 2, 3, 7, 14, 21, or 28 d. A significant interaction between DM and inoculation occurred on all days of fermentation except d 0. Lower DM corn (68 and 67% shelled corn, 71 and 64% ear corn) and fermented more and had higher concentrations of lactic acid, acetic acid, NH3 N, and lower pH than higher DM corn (76% shelled corn and 79% ear corn). Ethanol concentrations was affected by DM during the first 2 wk of fermentation with lower DM corn of both types producing more than their respective higher DM corn type. Both dry and reconstitued inoculated corn had lower pH and more lactic acid than control corn on d 28 of fermentation; however, no differences in lactic acid concentrations were detected until d 7 of fermentation. Inoculation also tended to reduce ethanol production. Shelled corn had a higher concentration of lactic acid concentrations were detected until d 7 of fermentation. Inoculation also tended to reduce ethanol production. Shelled corn had a higher concentration of lactic acid (d 2 and 3) and higher pH (d 1 and 2) during early phases of fermentation than ear corn, but overall pattern and end products of fermentation were similar for the two corn types.