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Abstract
Emphasis on quality factors in horticultural products has led investigators into studies on pigments because of their obvious effect on eye appeal. The anthocyanin patterns in nearly all commercial crops have been reported (Harborne, 1964, 1967; Geissman, 1962) but this does not mean that the information can be used directly. Pigment patterns are likely to vary in different cultivars and it is the responsibility of the investigator to check the pigment identities in his particular material. This paper is concerned with minimum criteria for publishable identification of an anthocyanin pigment.
Abstract
Quality measurement in all foods has been extremely important in the past and certainly will be no less so in the future. The trend towards a better nutritional delivery system, combined with a reduction in overall calories in our diet, will make fruits and vegetables even more important (5). Improved nutritional content will have to be accompanied by good sensory appeal because food that isn't eaten is of little importance in our diet Sensory appeal will have to be quantified, so it behooves the scientists in related areas to develop and interpret sophisticated tools to measure sensory appeal as an aid to the plant breeders.
Abstract
Instrumentation for color measurement is relatively well developed in terms of a convenient and accurate tool for the plant breeder. This paper discusses the development of a color solid and the meaning of a color reading in terms of the Judd-Hunter solid. Carrots are used as a specific example with references to squash, sweetpotatoes and red fruit juices. Color measurement can be used to predict the appearance of a fruit or vegetable which in turn can be used to predict the consumer acceptance in terms of appearance for the product. These methods are fairly accurate and are limited only by the ingenuity of the operator to present the sample to the instrument. The readings will reflect the visual impact from all factors which affect the color. It is unlikely that a color reading can be used to follow the development or degradation of a single pigment unless the system under study has only one predominant pigment. Such cases are relatively uncommon with fruits and vegetables.
Abstract
The introduction of colored mutants and their development into commercial varieties of red pears has attracted considerable attention since the fruit has a very attractive appearance (4,6). Dayton (1) reported that Starkcrimson, a mutation from Clapps Favorite, differed from all other red sports in having approximately 50% of cells in the outer hypodermal layer colored with anthocyanin. The Eureka variety had approximately 10% of epidermal cells colored. All other red sports had anthocyanin only in the second histogenic layer. The epidermis was colorless, together with one or two cell layers below this. Starkcrimson and, for example, Max-Red Bartlett, a sport of Bartlett, probably developed from different gene mutations. It was of interest to determine whether the anthocyanin pigments were identical in the two varieties.
Abstract
The anthocyanin pigments in ‘Durham’ fruits are cyanidin-3-glucoside (Cn-3-G), cyanidin-3-sophoroside (Cn-3-GG), cyanidin-3-rutinoside (Cn-3-RG), and cyanidin-3-glucosylrutinoside (Cn-3-GRG). The pigments in ‘Heritage’ fruits are Cn-3-G and Cn-3-GG. ‘Durham’ fruits are an excellent source of “marker” pigments.
Abstract
Anthocyanin content is one of the limiting factors in the production of cranberry juice cocktail, yet the press cake contains approximately 40% of the pigment of the berries. The pigment can be recovered by extracting the pomace with methanol containing 0.03% HCl. Other solvents are less effective. A single extraction from whole ground pomace at a 5:1 solvent:pomace ratio will extract approximately 50% of the pigment. A multiple extraction will remove over 90%. Grinding the pomace reduces the time of extraction from several hours to less than ½ hr. The methanol in the pigment solution can be removed by distillation under vacuum and the resulting aqueous solution absorbed on an Amberlite C G-50 resin. The resin absorbs the anthocyanin and many of the impurities can be rinsed off the column with water. The pigments can be eluted with 0.0001% HCl in ethanol and concentrated to provide a concentrate for addition back to the juice.
Abstract
Five anthocyanin 3-biosides are commonly known (4). Recently, a new one, cyanidin-3-arabinoglucoside, was added to the list (7). This short communication reports the isolation and identification of a 7th 3-bioside, pelargonidin-3-rhamnogalactoside, from the fruits of dogwood, also known as cornelian cherries (6).
Abstract
The effectiveness of gamma radiation as an enhancer of anthocyanin and flavonol pigment synthesis in cranberries was determined. Three different maturities of cranberries, based on their degree of coloration, and radiation levels of 150 and 300 krad were employed. The changes in the anthocyanin and flavonol pigments were measured quantitatively at regular intervals during storage. Radiation had a beneficial effect on the pigmentation of full-red cranberries and resulted in a significant increase in the anthocyanin and flavonol pigment contents. Effects on the less colored berries were not as great and in some cases flavonoid synthesis was reduced. The radiation induced changes were strictly quantitative in nature and there were no qualitative changes in the anthocyanins and flavonols. The visual effects of radiation on cranberries were minor softening and a stimulation of pigment production in the endocarp area of the fruit, resulting in internal coloration of the fruit. It was concluded that gamma radiation has an effect on the biosynthesis of the pigments involved and that the maturity stage of the cranberries was the controlling factor in determining the degree of response to radiation treatment. A possible mode of action of radiation on flavonoid synthesis was postulated.
Abstract
The anthocyanin pigments in Cotoneaster divaricata Rehd. & Wils. berries are Pg- and Cy-3-galactoside. The pigments in Berberis thunbergii DC berries are Pg- and Cy-3-glucoside.
Abstract
A standard method is proposed for the quantitative determination and reporting of cranberry pigments.