2010 Annual Report
The goal of this project is to evaluate the usefulness of regionally gown feedstock which contributes directly to Objectives 2 and 3 of the in-house project. A fermentation residue of a sugarcane-ethanol plant was the initial substrate tested for fungal protein production for aquaculture feed applications. The potential of producing a protein-rich fungus as an aquaculture feed ingredient on vinasse generated during sugar-based ethanol fermentation was studied. The results showed prolific fungal growth on vinasse with nutrient supplementation. The molasses-vinasse generated the highest specific fungal biomass yield. Organic and inorganic materials were significantly reduced. Thus, the treated effluent could be recycled as process water or used for land applications.
The fungal biomass was found to have 45.5% crude protein with significantly high amino acids. Feasibility of fungal cultivation on crude glycerine, a byproduct from biodiesel production, was confirmed in a laboratory study. The highest specific fungal biomass yield was obtained from the crude glycerine sample. The effluent after fungal fermentation of crude glycerine showed significant reduction in organic matter. Preliminary data on front-end processed banagrass juice demonstrated its potential as a substrate for fungal biomass production. Nearly 25-35% of the moisture found in the freshly harvested material was removed in the form of a high organic, nutritious liquid.
Since the shelf life of fresh kava juice kept at 4°C was less than 3 days, a pasteurization process was required to prolong the shelf life of juice to 5-7 days at refrigerated temperature. Pasteurization of kava juice using a continuous flow microwave heater showed the adequate lethal effect to the juice without major deterioration of food quality. It was found that the countable amount of E. coli K-12 was decreased at the treatment time of 30 seconds. One more recirculation process to double the treatment time would meet the commercial pasteurization requirement.
The effects of transport cost on the comparative advantage of Hawaii and its competitors were studied. While many believe that it might not be possible to attain 100% food self-sufficiency, there are certainly merits to taking advantage of the recent transport cost increase to replace some of our imports by local production both on food security and environmental sustainability perspectives. The overall result suggests that there was a case for (i) Hawaii to shift its attention to producing more lower-valued fruits and vegetables, in addition to producing for niche markets, most especially when transportation costs are expected to increase in the long run; and (ii) Oahu to consider producing more fruits and vegetables than what it is currently producing to decrease its dependency on other islands and the U.S. mainland. Whether these are feasible and worthwhile ventures will certainly depend on their economic viability.
This project is monitored via progress reporting, meetings, site visits, and telephone and email communications.