Digitized by Kansas State University Libraries

Raw product value of vegetables for processing in the Northwest used to be established by a competitive market involving proprietary processors and growers. Due to the relocation of proprietary processors to the Midwest, this competitive market has eroded forcing cooperative processors to seek other means to set raw product values. In the absence of a competitive market for raw product, cooperatives must rely on an average of last year's prices paid by processors in a given region to value raw product. This method of lagged averages may be resulting in misallocated contracted acreage to grower-members of cooperatives, and inappropriate production levels of the processed good given market conditions. Therefore, the principal objective of this research is to develop and evaluate alternative methods of forecasting raw product value. Since the market for processed vegetables at the retail level is competitive, one alternative method employed was to use a forecast of supply and determinants of demand affecting retail price to forecast raw product value. These explanatory variables were regressed against raw product values of various crops obtained from a northwest processing and marketing cooperative. The raw product values were expressed as net returns/acre to the crops under investigation. The estimated equations, which had adjusted R²'s ranging from .267 to .851, were used to forecast raw product value. A second forecasting method investigated in this study was an exponential smoothing model. Raw product value forecasts were generated over two different time horizons, identified by the cooperatives' accounting procedures. The two alternative forecasting methods were compared to each other, and to the method currently in use by the cooperative, with the aim of determining the most accurate forecasting technique. Results showed that both the econometric and smoothing approaches fit the data better over the estimation period than did a naive lagged price estimate resembling the present method in use by the cooperative. The econometric method also fit the data better than did the smoothing approach. The econometric model provided poor forecasts for the longer forecast horizon, but proved to be effective in the shorter. The smoothing technique forecasted more effectively in the longer forecast horizon as compared with the shorter. These results suggest the importance of the forecast horizon in determining the more appropriate forecasting technique. Both forecasting techniques proposed in this study produced forecasts which were more accurate than the cooperative's present method at least half of the time. This suggests that viable alternatives to the present method of establishing raw product value exist for agricultural cooperatives. / Graduation date: 1986

This investigation was concerned with the reduction of waste in raw vegetables and fruits between the times of harvest and consumption. Reduction of spoilage in produce was attempted by means of chemical and. physical agents as well as a combination of both. The first phase of the work consisted of an evaluation of a number of chemical compounds with respect to their effectiveness in reducing post-harvest spoilage. The second part dealt with an evaluation of several transparent films applied to raw produce as wrappers and their effect on the keeping quality of the plant material until consumed. Finally combinations of surface disinfection and overwrapping were evaluated for effectiveness against raw produce spoilage. 1. Disinfection Approximately 26 compounds were tested as aqueous dips using 3 concentrations of each on 7 major vegetables and 2 fruits. The following types of compounds were studied. 1. Quaternary ammonium compounds (chlorides, bromides and pyridinium derivatives) 2. Chlorine liberators (organic and inorganic) 3. Phenols (simple and poly-phenols) 4. Quinones and hydroquinones 5. Salts of fatty acids 6. SO₂ liberators 7. Benzoates The chemical treatments were evaluated for each produce by comparison with untreated controls using duplicate tests with triplicate samples for each chemical and concentration. Promising treatments were found for all but one produce (strawberries). The treatments showing promise for each of Pascal celery and Emperor grapes were further tested on a larger scale uaing commercial size units of produce as test samples and long term cold storage. Three chemical treatments for each product were judged satisfactory enough to warrant further testing by means of field trials. The chemicals found most promising for celery were Onyxide, Cetab and Decco while Roccal, Dowicide C and Phygon were selected for grapes. A field test of the three above mentioned treatments for Pascal celery was completed. One thousand bunches per chemical were tested under commercial conditions of dipping and storing. An equal number of untreated bunches was also tested. Half-lots of each treatment were evaluated on each bunch for 11 subjective characteristics and standard mold and bacterial counts of each crate of celery were made after 8 and 14 weeks of storage. On the basis of a statistical analysis of the results, 0.1% Decco of pH=5 can be recommended for the reduction of general rot development in cold storage Pascal celery. Onyxide and Cetab significantly reduce the development of mold but commercial application cannot be recommended because the amount of visible stalk injury was significantly increased over that shown by corresponding untreated or Decco treated celery. 2. Prepackaging The following films were compared for their merit in prolonging the salable life of raw produce. Pliofilm 75FF, Pliofilm 75N2, Pliofilm 75P6A, Cellophane 300LSAT, Cellophane 300MSAT-86, Lumarith P-912, Dupont Acetate 100CA48, Polythene and Kodapak II-130. Wrapping techniques were also evaluated using the followng variations; Complete seals, tent-flap closures, single hole punctures, multiple punctures and windo bags. The following products were studied: celery, tomatoes, carrots, lettuce, cauliflower, chopped salad mix, spinach, strawberries, raspberries, blackberries, and boysenberries. Harvested produce was packaged both before and after the removal of field heat. Behavior of the pre-packaged products in both 33°F storage and subsequent 8O°F storage was studied. Cold storage was extended as long as 120 days while subsequent holding at room temperature varied widely from produce to produce. Observations were made at regular intervals for each product. Several hundred uniform samples were evaluated for most products using duplicates of each treatment for every observation period. Evaluation of most samples included weightloss, C0₂ (and sometimes O₂) of the container atmosphere, mold and decay development, flavor, color, odor, wilting and shriveling. The following conclusions were drawn: All films and wrapping methods affect produce quality. For each produce, treatments could be singled out which were superior to unwrapped controls. However any particular film and type of seal found to be superior for one produce was often not acceptable for another fruit or vegetable. Among the factors found to be critical for the proper choice of treatment were type of produce, produce temperature when packed, length of storage, and temperature of storage. A. Cold Storage For most products, the partially sealed, low permeability MSAT containers and the completely sealed Polythene wraps scored highst for overall product quality. These treatments prevented the accumulation of undesirable CO₂ while at the same time protecting the produce against weightloss and consequent wilting. For some produce, especially berries, wilting was not apparent even in high permeability films such as acetates. B. Warm Storage For produce with high respiration rates (spinach, and berries) only acetate films were acceptable as wraps. The partially sealed low permeability films maintained good quality in warm storage but the high humidity within the package was conducive to micro-organism activity. Thus, in many cases samples disinfected prior to packaging in those films improved the warm storage quality. Disinfection also improved the quality of tomatoes and chopped salad mix in acetate wraps. Of the high permeability films, no significant difference was found among the Dupont acetate, Lumarith and Kodapak II. The type of seal also did not affect the characteristics of these wraps. The low permeability films differed principally in the amount of CO₂, retained by the container during storage. The Pliofilms retained the highest C0₂, levels followed by LSAT and then MSAT Cellophane. The sealed polyethylene, the single puncture and tent flap MSAT wraps exhibited similarity, especially with respect to C0₂ accumulation. The multiple puncture low permeability wraps showed characteristics between acetates and the last mentioned group. Correlation between CO₂ accumulation and off-flavor formation could be determined for most products. Higher CO₂ levels were tolerated at short storage intervals without off- flavor formation by most products but the rate of change in CO₂ tolerance varied from produce to produce. Correlation between % weightioss and degree of wilting could also be expressed as a function of the pre-packaging treatments used. Storage infection was eliminated by all films independent of the type of seal used. It should be emphasized that only a study of the resuits and relationships discussed under each product can serve as a basis for future work and commercial application of the methods presented in this work. / Graduation date: 1950

Thesis (M.S.)--University of Delaware, 2009. / Principal faculty advisor: John C. Bernard, Dept. of Food & Resource Economics. Includes bibliographical references.

Thesis--Auburn University, 2008. / Abstract. Includes bibliographic references (p.57-67).

Thesis (Ph. D.)--University of Pretoria, 2001. / "June 2001." Includes bibliographical references (p. 164-181). Adobe Acrobat Reader needed to open files.

This publication is issued by The University of Arizona Agricultural Extension Service and Agricultural Experiment Station in cooperation with the Arizona Crop and Livestock Reporting Service of the United States Department of Agriculture, Agricultural Marketing Service, Crop Reporting Board. / This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.

The principal objectives of this study are to identify the production factors that influence cocoa productivity at the smallholder's level and to examine resource allocation and technical efficiency in cocoa production. Cross-sectional data collected from 260 cocoa smallholders were used for the study. Both the average production function estimated by the Ordinary Least Squares techniques and the frontier production function estimated by the Linear Programming methodology were employed in the analysis. The results indicated that the input factors which had a significant impact on the production of cocoa were land size, labour, living capital, farm implements and fertilisers. Among the management proxies, only farmer's age, extension contact, farmer's education and the practice of keeping farm records and accounts were important. The data presented in this study 1end support to the hypothesis that the cocoa smallholders were highly inefficient allocatively. Inputs comprising land, fertilisers, and farm implements were underused while labour and living capital were overused. Technical inefficiencies were also present in the study area. The study revealed that a large proportion of the farmers have output levels below their potential. Output could be increased between 18 to 52 per cent if all the least efficient farmers attained those levels of technical efficiency that were achieved by the best farmers in the sample. The variations in technical efficiency in this area were explained by differences in land size, farmer's educational level, their age and the practice of keeping farm records and accounts. This study emphasises the need that increasing efforts must be directed at the least efficient farmers through better and effective management practices and better organization of farm activity without major new investments, at least in the short-run.

No description available.

Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1977. / Bibliography: leaves 335-341. / xxvii, 341 leaves ill