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Four assumptions-- 1. That there is an effective and potential demand for processed fruit products in the Western State of Nigeria. 2. That current supply of raw materials in the Western State of Nigeria is more than sufficient to meet the increased demand which the short-term addition or expansion (or both) of market opportunities as provided by processors will stimulate. 3. That farmers could be better-off economically by widening their margin. 4. That while a processing unit may have many objectives, like survival, large size, power and status, the overriding motive of the unit is to try to maximize profit. -- were made in conducting this study which is an attempt to understand the impact a particular processing firm in the Western State of Nigeria has made on farmers in its surrounding, and a postulate of the role such firms could play in the improvement and expansion of fruit crop production, especially in the context of the stage of development Nigeria is today. With orange and pineapple as fruits of emphasis, the field work, done in Nigeria, took 59 days (July 20, 1970, to September 17, 1970); 45 days spent in interviewing farmers, 12 days in watching processing activities of 'Blaize'--the fruit processor; and 2 days taken off in-between. Three major issues examined are 1. The system of farming practiced by the producers--farmers producing for Blaize--particularly the farming changes (if any) induced by the addition or expansion (or both) of market opportunities as provided by the processor--'Blaize'. 2. The organization, activities and program of the processor-buyer (Blaize) as they relate to the purchase of orange and pineapple from Abeokuta area. 3. The kind of relationship which has been established between the processor firm (Blaize) and farmers who supply to it. Findings are: 1. The area of land planted to orange and pineapple in Abeokuta has been increasing over the years. 2. Farmers are responsive to price incentives; and are willing to increase their productivity to take advantage of profit opportunities, but they tend to guard against a long-term curtailment of food production. 3. Farmers earn their most cash-income from farming. 4. Nonfarm activities of the present farmers provide an increasingly smaller resource potential for production increase. 5. Capital, labor, good roads and transport are major constraints on farmers' production in Abeokuta area. 6. Abeokuta farmers diversify, but they grow more crops for domestic market than for export. 7. Land-use in Abeokuta features 9.2 percent devoted to ara-ables, 16.3 percent to tree crops, about 11.6 percent and 15.4 percent devoted to orange and pineapple, respectively; and 60 percent still residual. Average land-size per farm family is 32.7 acres, all scattered on an average of 8.6 plots. 8. Fruit growers in Abeokuta area are market oriented. 9. People in age brackets (26-37) and (37-46), as compared with other age brackets, have the largest amount of land, are more numerous, and are more market oriented. Areas of possible further investigation are: 1. Analysis of consumer demand. 2. The difficulties which may be faced by the expansion of processed fruit products when such will be meant for exports. 3. Promotional measures, and the utilization of by-products of processing plants. 4. Analysis of the existing marketing channels and services. 5. Capacity assessment of any given processor-plant. 6. The determination of the most suitable location of any proposed plant. / Graduation date: 1973

Sensory evaluation and instrumental methods were applied to the evaluation of strawberry juice concentrate (68°Brix) stored at 20°C which had been produced both commercially (C-SJC) and in a pilot plant (SJC). Sensory evaluation included taste and aroma ratings by intensity scaling and time-intensity of taste, and visual colorimetry by matching Munsell color chips. Instrumental analyses included tristimulus colorimetry (i.e. Hunter colorimeter), spectrophotometric colorimetry for pigment analyses, titrametric analyses for acidity (pH and titratable acidity) and free α-amino acids (formol number), and headspace gas analyses for CO₂ and O₂. During six days storage of C-SJC, a decrease in concentration of anthocyanins and increase in polyphenolics (tannin) was associated with an increase in astringency. Free α-amino acids were observed to decrease, while CO₂ was released. These changes were associated with an increase in musty/moldy and pungent aromas. Free sugars and titratable acidity did not change. The pilot plant SJC was processed from blanched and unblanched fruit to evaluate the relative importance of oxidase activity (i.e. polyphenoloxidase) prior to pasteurization. The blanching treatment increased the astringency and sourness in unstored SJC. These affects were associated with an increase in concentration of polyphenolics (tannin). During storage, the blanch treatment decreased the rate of anthocyanin loss and decreased the release rate of CO₂, yet degradation rates were still high. The 0₂ concentration in headspace did not change significantly during storage indicating that polyphenoloxidase (PPO) activity during storage was low. The musty/moldy and pungent aromas increased similarly to C-SJC. A chemical mechanism accounting for these changes is proposed where products from the oxidative degradation of ascorbic acid contribute directly or indirectly to the degradation of anthocyanins to yield browning. Further, high initial concentrations and subsequent decreases during C-SJC storage of free α-amino acids indicate that Strecker degradation is a participating mechanism. Associations of browning with the development of off-flavors suggest this chemical mechanism forms odor-active volatile compounds. / Graduation date: 1989

Methodology for characterization of the phenolic profile of apple, pear and grape juice was developed. It utilized High Performance Liquid Chromatography (HPLC) for separation of individual phenolic compounds and Diode Array Detection for recording the Ultra-violet (UV) spectrum of chromatographic peaks. The high resolution achieved and the ability of recording more than one wavelength simultaneously, allowed for quantitation of phenolic acids (cinnamics and benzoics), flavonol and dihydrochalcone glycosides, arbutin and hydroxymethylfurfural (HMF) with minimum sample preparation. Quantitation of procyanidins, however, required preliminary isolation and analysis in a separate run. Procyanidin isolation based on Sephadex IH-20 resulted in high recoveries and degree of reproducibility. The methodology was applied to study the influence of variety, post-harvest storage, SO₂, initial high temperature short time (HTST) heat treatment, enzymatic clarification, fining, bottling, concentration and storage on the phenolic composition of apple, pear and grape juice. Processing with SO₂ inhibited extensive phenolic oxidation during pulping and resulted in increased phenolic yields. Initial HIST treatment protected phenolics extracted in the juioe from degradation during processing. Cinnamic hydrolysis occurred during enzymatic clarification. The hydrolytic activity was removed with fining or bottling. There was no appcirent reduction of phenolics with fining. Procyanidins were sensitive to the heat applied during bottling and concentration. Storage of juice concentrates for nine months at 25°C resulted in formation of HMF, considerable degradation of cinnamics and dihydrochaloones and total loss of procyanidins and flavonols. The effect of diffusion extraction at different teirperatures on the phenolic composition of apple juice from different varieties was also studied. Up to a three-fold increase in cinnamics and a five-fold increase in dihydrochalcone glycosides were measured in diffusion extracted juice relative to juice extracted with conventional pressing. The increase in procyanidins and flavonols was even higher. / Graduation date: 1989

The purpose of the present study was to investigate the effect of a number of physical and chemical attributes upon muskmelon texture as described by sensory evaluation. Measurements of turgor pressure, percent moisture, total sugars, alcohol-insoluble-solids, three pectic fractions, total pectic materials, starch and cellulose were performed on 50 melons. The melons were purchased at random from a retail market in Corvallis, Oregon, over a five-week period during July and August, 1966. Subjective evaluation of textural quality was provided by a five-membered panel employing a pre-tested ballot. On five-point scales, judges rated resistance to cutting, resistance to biting, resistance to crushing, crispness, fibrousness and sweetness. Simple and multiple correlation analyses were performed to elucidate relationships between the objective and subjective observations. Considerable variation was found among melons for most of the attributes. Variation was largest in the case of water-soluble pectic substances and cellulose and least for alcohol-insoluble-solids. According to the results of this study, melon texture is determined to a great extent by the type and amount of cell wall constituents. Significant multiple correlations were found between cell wall constituents, cellulose and protopectin, and sensory panel scores for resistance to cutting, resistance to biting, resistance to crushing and crispness. Fruit maturity, as inferred from starch and protopectin content, also exerted an effect upon texture. Significant multiple correlations were found between starch and protopectin and panel scores for resistance to cutting, resistance to crushing and crispness. Although not specifically related to texture, a significant and positive simple correlation was found between total sugars and sweetness. Similarly, significant negative correlations were found between starch and total sugars and starch and sweetness. Turgor pressure, percent moisture, alcohol-insoluble-solids, total sugar, water-soluble pectic substances, pectates-pectinates and total pectic materials were found not to be reliable indicators of muskmelon texture. Although turgor pressure did not exhibit a significant relationship to any textural aspects, a trend was observed in the data. As a result of this observation and difficulty encountered in measuring turgor pressure, further work with this variable is recommended. Proximate composition of the melons analyzed compared favorably with published data. This observation lends confidence to the methods and analyses employed. Large standard deviations calculated for some of the attributes measured emphasize the extent of variation among melons, the difficulty in assessing texture in an objective manner and the problem encountered in marketing and purchasing the fresh fruit. / Graduation date: 1968

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