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  • Author or Editor: E.P. Maness x
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Abstract

Since the techniques of column, paper, thin layer, and gas chromatography are playing a rapidly increasing role in horticultural laboratories and in the interests of horticulturists, two papers on chromatography technique are presented in this issue. W. E. Ballinger and Eleanor P. Maness of North Carolina State University offer an improvement in paper chromatography which has enabled them to materially increase laboratory productivity in the separation of anthocyanins from blueberries. M. Allen Stevens of Campbell Research Institute briefly, but concisely, surveys the principles of gas chromatography and illustrates several horticultural research potentials with this new medium.

Open Access

Abstract

Fruit anthocyanins (ACY) of eight Prunus spp. representing two subgenera (subg.) and three sections (sect.) were analyzed using high-performance liquid chromatography (HPLC). Fruit of P. angustifolia Marsh., P. hortulana Bailey, and P. maritima Marsh. all North American members of subg. Prunus sect. Prunocerasus, were qualitatively identical in ACY composition, containing cyanidin-3-glucoside and cyanidin-3-rutinoside. Fruit of P. cerasifera Ehrh. and P. spinosa L., both Eurasian members of subg. Prunus sect. Prunus, contained small amounts of peonidin-3-gIuco-side and peonidin-3-rutinoside, in addition to the 3-glucoside and 3-rutinoside of cyanidin. Fruit of P. besseyi Bailey and P. pumila L. (subg. Lithocerasus sect. Microcerasus) contained cyanidin-3-glucoside and cyanidin-3-rutinoside. Fruit of P. pumila also contained trace amounts of peonidin-3-rutinoside. Fruit of P. japonica Thunb., a Chinese member of subg. Lithocerasus sect. Microcerasus, showed a complex ACY profile distinct from P. besseyi and P. pumila.

Open Access

Abstract

Eight lines (2 cultivars and 6 selections) of Euvitis grapes in 1982 were stored for 4, 6, 7, and 8 weeks at 0° ± 0.5°C without sulfur dioxide (SO2) generators and for 4, 8, 12, 16, and 20 weeks with SO2 generators in 5.7-liter telescoping, corrugated cardboard shipping containers with polyethylene liners. Grapes stored without SO2 were of poorer appearance after 4 weeks than those stored with SO2 after 8 weeks. After 16 weeks of storage with SO2, 4 of the 8 lines still had appearance ratings similar to those before storage. Overall, good flavor was maintained over 7 weeks without SO2 and over 12 weeks with SO2. During 8 weeks of storage without SO2, 6 of the 8 lines developed 23% to 60% decay. In contrast, 6 of the 8 lines stored with SO2 for 16 weeks developed 3% or less decay. SO2 injury (percentage by number) ranged from 0% to 59% but was judged to be objectionable in flavor or appearance in only 2 instances. All lines stored well for 12 weeks with SO2. Of the 8 lines, ‘Suffolk Red’ was judged to be outstanding. After 20 weeks of storage with SO2, ratings of its appearance and flavor were equal to those before storage; decay was only 3.5%.

Open Access

Abstract

Anthocyanins of ripe fruits of 13 species of Vaccinium (12 species of the Cyanococcus and 1 species of the Polycodium sub-genera) collected in the eastern United States and grown together near Castle Hayne, North Carolina were hydrolyzed to yield aglycones and sugars. TLC separation and identification of these hydrolysates indicated that anthocyanins of the 12 species of the sub-genus Cyanococcus (true blueberries; Camp) contained 5 aglycones (> means “in greater quantity than”) (delphinidin > cyanidin > malvidin > petunidin > peonidin) and 2 sugars (galactose > arabinose). Anthocyanins of Polycodium representative V. stamineum (deerberries) differed from those of representatives of Cyanococcus in that they yielded only large amounts of the aglycone cyanidin and trace amounts of peonidin. Hydrolysis of anthocyanins of fruits of V. stamineum and 7 species of Cyanococcus yielded glucose. Thus, species of Cyanococcus appeared to have a similar anthocyanin content. Anthocyanin contents of Polycodium (V. stamineum) were different than those of Cyanococcus but generally the same as those reported for cranberries (V. macrocarpon, sub-genus Oxycoccus). Reports in the literature indicate that anthocyanins of other sub-genera of Vaccinium contain xylose (V. myrtillis; bilberry; cyanidin-3-xylosylglycoside) and rhamnose (V. vitis-idaea; cowberry; delphinidin-3-glycoside, 5-glycoside, and 3-rhamno-glycoside). Thus, as indicated from this initial study, fruits of the genus Vaccinium appear to vary in anthocyanin content with sub-generic classification.

Open Access

Abstract

HPLC analysis of seven blueberry species, V. ashei Read (2n = 6x = 72), V. constablaei Gray (2n = 6x = 72), V. corymbosum L. (2n = 2X = 24 and 2n = 4X = 48), V. elliotti Chap. (2n = 2X = 24), V. pallidum Ait. (2n = 2X 24 and 2n = 4X = 48), V. simulatum Small (2n = 4X = 48), and V. tenellum Ait. (2n = 2X = 24), identified the 3-monoarabinosides, 3-monogalactosides, and 3-monoglucosides of cyanidin, delphinidin, malvidin, peonidin, and petunidin in each species. Differences in relative percent of individual anthocyanins in some instances were useful in distinguishing among both species and ploidy levels. Differences in percent aglycones were also useful in distinguishing among species. Evidence presented does not support grouping V. elliotti, V. simulatum, and V. constablaei into a single “highbush” species (i.e., V. corymbosum). Percent cyanidin-3-galactoside appeared useful in distinguishing ploidy levels in V. pallidum and between 4X V. pallidum and the “palloid” phase of V. constablaei (6X).

Open Access

Abstract

The relationship of holding temperature and stage of ripeness to decay development of blueberries (Vaccinium corymbosum L) was determined comparing 6 sets of 5 ripeness classes (light-sorted; 740-800 nm) stored at 1.1°, 10.0°, and 22.2°C. On each of 6 dates, 1 set (3 temperatures × 5 ripenesses × 4 replications) was removed from storage and sorted for decay. Regardless of cultivar or stage of ripeness, all blueberries stored at 22.2° decayed rapidly (within 5 days). Only when the blueberries were held at 1.1° did the time and expense of light-sorting appear economically justifiable; i.e., overripe berries (% soluble solids (SS)/% acid (Ac) ratio = 30) required about 12 days while just-ripe blue fruits (SS/Ac = 10) required about 32 days to develop 20% decay. Estimates of maximum degree of ripeness (SS/Ac) for fresh marketing (< 20% decay at retail) were made: Trans-Atlantic (up to 20,) transcontinental (up to 27), and local (⋜ 1200 km) (up to 30). Fruit riper than SS/Ac = 30 should be processed within 24 hours.

Open Access

Abstract

The anthocyanin (Acy) content of 12 Euvitis × Vitis rotundifolia hybrids, 3 V. vinifera L., one V. × labruscana, and one V. rotundifolia Michx. clone were analyzed by high performance liquid chromatography (HPLC) techniques. All intersubgeneric hybrids contained mono- and diglucoside Acy, and all but one produced acylated Acy. A total of 40 pigments was separated, with ‘Concord’ having the most at 31. An additional unidentified pigment was detected in ‘Noble’. Sufficient variation was present in the hybrids for selection of genotypes that would improve color of wines. Relative Acy content (percentage of total) in the hybrids ranged from 2.3% to 44.3% for malvidins, 0.7% to 30.3% for petunidins, 0.8% to 69.2% for peonidins, 0.0% to 17.2% for cyanidins, and 0.5% to 52.3% for delphinidins. Relative content of acylated Acy forms in the hybrids ranged from 0.0% to 51.1%. Total Euvitis-type pigmentation (monoglucoside plus acylated Acy) in the hybrids ranged from 19.5% to 55.0%.

Open Access

Supersweet corn with the shrunken-2 gene (sh2) has shown good quality after frozen storage. A study was undertaken to further evaluate the quality of supersweet corn (cv Florida Staysweet) unblanched or blanched then frozen. Samples were evaluated every 4 months for 12 months for peroxidase activity. sugar composition, water soluble polysaccharides and organoleptic qualities. Peroxidese activity changed in unblanched corn at each sampling date, which was consistently higher than in blanched corn. Sucrose and total sugars declined during storage. Sucrose was highest in blenched samples and reducing sugars were highest in unblanched samples. WSP content was low in all samples, but lower in blenched compared to unblanched samples. Taste panelists discerned differences between blanched and unblanched corn at 8 months when blanched samples were rated as more yellow than unblanched. However, no differences were found for taste between blanched and unblanched samples for taste at 12 months. These results indicate that sh2 sweetcorn maintained good eating quality for 12 months of frozen storage with or without blanching.

Free access

Abstract

The 3-monoarabinosides and 3-monogalactosides of delphinidin (Dp), petunidin (Pt), malvidin (Mv), and peonidin (Pn) as well as small amounts of the 3-monoglucosides of Dp, Pt, Mv, Pn, and cyanidin (Cy) were isolated from ripe blueberry fruit, variety ‘Croatan’. Small amounts of the 3-monogalactoside of Cy were present also. None of these 14 anthocyanins (Acy) were acylated. The major Acy were (in descending order): Mv-3-galactose, Dp-3-galactose, Dp-3-arabinose, Pt-3-galactose, Pt-3-arabinose and Mv-3-arabinose.

Open Access

Abstract

Fruit, stems, tendrils, leaves, and leaf petioles of4Noble’ muscadine grape (Vitis rotundifolia Michx.) were analyzed using high performance liquid chromatography (HPLC) techniques. All five of the known 3,5-diglucoside forms of delphinidin (Dp), cyanidin (Cy), petunidin (Pt), peonidin (Pn), and malvidin (Mv) present in fruit of muscadine grape were detected in all sampled tissues except leaves, which contained only Dp, Cy, and Pt in detectable quantities. A sixth unknown pigment was detected in the fruit, and Dp 3-monoglucoside was detected in the leaves. Correlations were calculated to explore pigment relationships between fruit and vegetative tissues. Use of tendrils was best for predicting fruit Cy (r = 0.60), Mv (r = 0.57), Pn (r = 0.66), and Pt (r = 0.87). Use of stem tissue was best for predicting fruit Dp (r = 0.66). Prediction equations are given, and prediction of Cy could be improved by using both tendril and leaf measurements in a multiple regression (r = 0.80).

Open Access