Ensiling is a promising low-cost preservation approach that allows for a year-round supply
of kelp feedstock for biofuel production via anaerobic digestion. In this study, farm-grown kelps of
known age were ensiled with and without the addition of lactic acid bacterial (LAB) inoculant for
a duration of up to one year in order to test long-term storage suitability. The study looked at the
impacts of different bacterial inoculums on the chemical and microbial composition over the duration
of storage. Significant fluctuations in the pH were observed during ensiling, leading to some cases of
secondary fermentation and a loss of volatile components; however, over 12 months, the total mass
loss was <2% on average. Biochemical compositional changes occurred in the silage over a period
of 12 months, but protein, lipid and carbohydrate content remained suitable for biogas production.
Microbial analysis showed variability in the bacterial distribution between the ensiled samples that
was coincident with pH variability. Despite this variability, the bacterial communities underwent a
succession with a selection for ensilage bacteria and drop in spoilage organisms. This shift supports
the viability of this ensiled material for future usage. The impact of ensiling on bioenergy production
through anaerobic digestion is explored in the second part of this two-part paper.