Page Banner

United States Department of Agriculture

Agricultural Research Service

Related Topics

Research Project: UHM-COLLABORATIVE EFFORT FOR EVALUATING REGIONALLY BASED FEEDSTOCK AND CO-PRODUCTS FOR AQUACULTURE AND LIVESTOCK

Location: Tropical Crop and Commodity Protection Research

2010 Annual Report


1a.Objectives (from AD-416)
The goal of this agreement is to carryout a collaborative research effort among PBARC, The College of Agriculture, Forestry and Natural Resource Management (CAFNRM) at the University of Hawaii at Hilo (UHH), and the College of Tropical Agriculture and Human Resources (CTAHR) at the University of Hawaii at Manoa (UHM) that addresses important agriculture problems in Hawaii. The specific problem to address is determined through consultation and agreement among the agriculture college deans of CAFNRM and CTAHR and the director of PBARC. The main objective of this SCA is to evaluate the usefulness of regionally grown feedstock for aquaculture and livestock.


1b.Approach (from AD-416)
In 2002, congress provided a set amount of funds to PBARC with the mandate that the funds should be split three ways among CAFNRM, CTAHR, and PBARC. The intent is to develop a mutually beneficial collaborative research effort that is formulated by the deans and the director of PBARC. The deans of CAFNRM and CTAHR, and the director of PBARC met and agreed to develop a research effort to evaluate the usefulness of regionally grown feedstock and co-products for aquaculture and livestock. Each institute would focus on research areas in which they have strengths and which would move the institutions closer to achieving the stated objective. To carryout the research plan, each dean will put out a call for proposals to their respective colleges for grant proposals to address the objective over a five year period. The proposals will be reviewed and selected by the deans and the director of PBARC, and any advisors that they may choose. To ensure that the research is focused on the objective and to assess progress, the investigators of the selected grants, the deans, and the director will meet annually to evaluate the work. Following the annual meeting, changes in the research personnel or focus may take place if needed. PBARC will have a research effort towards this objective but it will not have a call for proposals since the funds originally allocated to PBARC became part of their base budget. To maintain a degree of flexibility, the deans may use a small part of the funds to support other projects that may not be directly related to the main objective.


3.Progress 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.


Last Modified: 4/21/2014
Footer Content Back to Top of Page