Thompson Seedless grapes

Exploratory studies indicate that 64 mature Valencia oranges per sample, when picked in a consistent manner with 16 fruits from each of 4 randomized normal trees, suffice to give fair (10%) agreement between replicates such a sample ordinarily weighs from 18 to 24 pounds. Very cursory tests with Thompson seedless grapes demonstrate... 

Spanos, G.A. and Wrolstad, R.E., Influence of processing and storage on the phenolic composition of Thompson seedless grape juice, J. Agric. Food Chem., 38, 1565, 1990. 

Table III. Response of Thompson Seedless Grapes to KGA3 Sprays...

Figure 14. Thompson Seedless grapes 76 days after being sprayed on June 11 with KGAS...

Thompson Seedless treated at Davis Grapes only 62 32 8... 

Sweet-Wine Grapes Trousseau, Sultana, Palamino (Palomino), Thomson s Seedling (Thompson Seedless), Muscat of Alexandria,... 

Post-Prohibition. The repeal of Prohibition found eastern viticulture, what there was left of it, in deep depression. Unlike California, it was not helped by the huge grape deal directed at home winemakers and it had lost much of the fresh fruit market to Thompson Seedless, Flame Tokay, and Emperor from the Central Valley, short on flavor but long on shipability. 

Figure 4. Change in carotenoid contents during maturation of three varieties of grapes (A) Concord grapes (B) Thompson seedless and (C) Chilean red.

In this investigation we processed pears, apples and Thompson seedless grapes into juice and juice concentrate and tracked the compositional changes through processing and storage. The quality... 

Figures 1, 2, and 3 outline the unit operations for the different processing trials. SO2 addition is commonly used in commercial processing of Thompson seedless grapes into concentrates. We were particularly interested in its influence on composition and quality and did parallel trials with and without addition of 70 ppm S02 ...

Thompson Seedless Grapes) fs02 Addition, 70 ppm J Tno SO2 Addition)... 

Figure 1. Unit operations for processing Thompson Seedless white grape juice samples. (Reproduced from ref. 4. Copyright 1989 American Chemical Society.)...

Figure 9. Effect of processing and storage on the phenolics of Thompson Seedless grape juice. Unit operations code P, pressed juice E, enzyme clarification Ft, filtered B, bottled single-strength juice C, concentrate and CS, stored concentrate.

Good quality dried raisins (dried Thompson seedless grapes), dried flge and fresh figs (Callmyrna variety) were obtained from processors In the Fresno, California area and from local markets for comparison. Authentic chemical compounds for comparison were obtained from reliable commercial sources or synthesized by known methods. 

Low temperature strongly retards apparent cytokinin biosynthesis in corn roots (Atkin et al. 1973). Temperature affects the cytokinin content of the root exudate of Thompson Seedless grape vines in both a qualitative and quantitative manner. So-called Fraction 2 cytokinins are present in exudate of vines grown at 20° C but not in vines grown at 30° C (Skene and Kerridge 1967). 

Adsorption isotherms of potatoes were of sigmoid shape and were affected by drying method, temperature, and addition of sugar [85]. The freeze-dried product absorbed more water vapor than the vacuum-dried materials. The sorption isotherm prepared from fresh and freeze-dried Thompson seedless grapes indicated a hysteresis loop at both the upper and lower moisture level [86]. The isotherm sun-dried grapes were slightly lower than that of vacuum-dried grapes. 

Fig. C-15. Drying grapes in the California sun. Clusters of Thompson Seedless grapes are spread on paper trays laid down between the rows of vines. Two to three weeks of drying reduces about 4 1/2 lb 2 kg) of grapes to 1 lb (0.45 kg) of raisins. (Courtesy, California Raisin Advisory Board, Fresno, Calif.)...

Canned grapes— Almost all canned grapes are the Thompson Seedless or other seedless varieties. These grapes are mixed with peaches, pears, and pineapple as fruit cocktail or fruit salad. 

Many varieties of grapes are produced in California, but only four principal varieties have been found suitable for drying into raisins. These four varieties are the Thompson Seedless, Muscat, Sultana, and Zante Currant, and they are either sun-dried or mechanically dehydrated. 

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