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- Author or Editor: W. A. Sistrunk x
Abstract
The effects of bruising and chilling on color, hardcore, and carbohydrate composition in ‘Centennial’ and ‘Georgia Jet’ sweet potato roots (Ipomoea batatas (L.) Lam.) were observed after baking and boiling. ‘Centennial’ was better in color than ‘Georgia Jet’ by both cooking methods. There was a general increase in discoloration as storage was extended to 10 days. Baked roots were better in color than boiled by both Hunter Color Difference Meter and sensory scores. The incidence of hardcore was higher in ‘Georgia Jet’, and the amount increased with storage time at 2°C. Bruising did not influence hardcore, but bruised lots had more discoloration and received lower color scores. ‘Centennial’ was higher than ‘Georgia Jet’ in all carbohydrates except cellulose. All carbohydrates decreased during 10-day storage except sugars and water-soluble pectin. Cooking by baking converted more starch to sugar than boiling. Significant interactions occurred among cultivar, storage temperature, storage time, and cooking method that influenced the interpretation of the results.
Abstract
A processing study was conducted on 2 cultivars, 3 extraction temperatures, 3 storage temperatures and 3 storage times to assess differences in quality of juice of muscadine grape (Vitis rotundifolia Michx.) The 2 cultivars responded differently to all other variables in color changes. ‘Carlos’, a bronze-skinned grape was higher in acidity and lower in pH and total phenols than ‘Noble’, a black-skinned cultivar. Higher extraction temperatures leached out more acids, total phenols, and color. Color and overall quality changes were rapid at 32°C storage, making the juice unacceptable at 7 months storage. Greater changes in quality occurred when juice was extracted at 60° than at 24° or 80°.
Abstract
Two cultivars of spinach, blanched at 4 temperatures and for 4 lengths of time, were canned and analyzed during a 15-month storage period. ‘Bounty’, a savoyed-leaf type, had better color and texture than ‘Viroflay’, a smooth-leaf type, but was higher in oxalates, nitrate-N and nitrite-N. A blanch time of 12 minutes produced better color than a 4-minute blanch time. However, longer blanching leached out more solutes including total N, oxalates, nitrate-N and nitrite-N. Color, texture, total N, oxalates nitrate-N, and nitrite-N decreased as temperature of blanch increased from 71 to 89°C. During storage, canned spinach lost greenness and became darker as measured by the Hunter ‘a’ and ‘L’ respectively. However, the improved color from the 71 and 77°C blanch did not disappear during storage. There was a decrease in nitrate-N but an increase in nitrite-N during 15 months storage, especially in ‘Viroflay’.
Abstract
‘Elite’ (Vigna unguiculata (L.) Walp.), has been released by the Arkansas Agricultural Experiment Station, to meet the needs of gardeners and commercial processors for a well adapted cream type.
Abstract
Three cultivars of strawberries (Fragaria × ananassa Duch. cvs. Cardinal, A-5344, and Earlibelle) were harvested once-over by machine in 1975 and 1976 and separated into green and ripe fruit. Preserves and jam were manufactured from different combinations of sliced, ripe fruits, puree from ripe and from green fruit, then stored at 2°, 24° and 35°C for 0, 4 and 9 months. There were differences among cultivars and treatments in color attributes and sensory quality but both preserves and jams were highly acceptable from all cultivars and treatments. The greatest change in color and sensory quality was caused by storage at 35° for 4 and 9 months. Green fruit did not affect storage stability and development of browning. As much as half immature, green fruit can be used in the manufacture of preserves and jams without affecting quality in highly-colored cultivars.
Abstract
Hardcore was apparent in cooked sweet potatoes (Ipomoea batatas Lam.) which had been chilled and transferred to nonchilling temperatures prior to cooking. The severity increased with duration of chilling at 2°C. Hardcore was not observed in roots boiled immediately after chilling, although these roots were firmer than those not chilled. Enhanced levels of pectic substances, soluble in sodium hexametaphosphate, were associated with hardcore tissue, while starch, protopectin, and hemicellulose were related to enhanced firmness of continuously chilled roots. No differences in pectinmethylesterase activity were observed between storage treatments. Reduced levels of alpha amylase activity in continuously chilled roots probably accounted for the enhanced levels of starch after the roots were processed. From data on U.V. absorption, phenolic levels, and electrolyte leakage, we believe that hardcore develops when phenolics or related substances, and possibly cations, bind with cell wall materials.
Abstract
A single foliar spray of 25 or 28 ppm 5-chloro,2-thenyl, tri-n-butyl-phosphoniumchloride (CTBP) when the first flowers opened increased yields of 2 cultivars planted in late summer and 2 of 4 cultivars planted in late spring, 1970. Yield increases were due to more pods. In general, CTBP treatments that increased yields did not influence seed and fiber development, shear press values, and color of 4-sieve and 5-sieve pods that were canned. Also, Ca, Mg, P, and K levels of 4-sieve, deseeded 5-sieve, and seeds from 5-sieve pods were not influenced by CTBP treatments.
Abstract
Brown-end discoloration (BED) of broken snap beans (Phaseolus vulgaris L.) occurs whenever pods are held for several hours before processing. Increases in phenylalanine ammonia lyase (PAL), catecholase, and peroxidase activities as well as total phenolic content coincided with the development of BED. The intensity of BED and catecholase activity declined with increasing incubation temperatures (40 to 70°C). Perosidase activity did not decline until after 60° and PAL activity was stable through 70°. We therefore believe that catecholase oxidation of phenolic substances are directly associated with BED of snap beans.
Abstract
A 2-year study was conducted on the effects of cultivar, irrigation, ethephon (1976 and 1977) and harvest date (1977) on yield distribution and quality attributes of canned tomatoes. The Arkansas selections 74-41 and 74-42 produced higher yields of canning ripe tomatoes than either ‘Chico III’ or ‘Roma VF’ in 1976, while 74-41 and ‘UC-134’ yielded higher than ‘Chico III’ and ‘Roma VF’ in 1977. Ethephon increased the yield of canning ripe fruit in 1976 but not in 1977 when rainfall was higher. Selections 74-41 and 74-42 were highest in % drained weight retention in 1976 and % drained weight retention, viscosity and USDA color scores in 1977 when compared with other cultivars tested. Percent soluble and total solids changed with cultivar, year, harvest date, and irrigation. There was an increase in viscosity, % soluble and total solids, and shearpress values at higher density levels in selection 74-41 as compared to little or no change in ‘Roma VF’. Viscosity was also affected by irrigation and treatment with ethephon.
Abstract
A study was conducted on 2 cultivars of mechanically harvested strawberries (Fragaria × ananassa Duch.) to determine the effects of chemical treatments and heat on stability of color in frozen fruit for jam. Treatment with NaHSO3, citric acid or SnCl2 improved color of the jam when compared to the control, as demonstrated by Color Difference Meter (CDM) values and sensory ratings. The CDM color functions were higher on jam made from frozen puree than from frozen whole fruit, yet panel scores were significantly higher on jam from whole fruit. The jam made from frozen puree browned more during storage than that made from whole fruit. There were significant differences in color between cultivars and storage temperatures, but differences among treatments were larger. Treatment with NaHSO3, citric acid or SnCl2 offer possibilities for stabilizing color in jam.