Strawberries juice

Bakker, J. and Bridle, R, Strawberry juice color — The effect of sulfur-dioxide and EDTA on the stability of anthocyanins, J. Sci. Food Agric., 60, All, 1992. 

Total anthocyanins Strawberry juice 96.1-100.5% Odriozola-Serrano and others 2008a... 

Odriozola-Serrano I, Soliva-Fortuny R, Gimeno-Ano V and Martin-Belloso O. 2008a. Kinetic study of anthocyanins, vitamin C, and antioxidant capacity in strawberry juices treated by high-intensity pulsed electric fields. J Agric Food Chem 56 8387-8393. 

Torreggiani, D., Fomi, E., Guercilena, I., Maestrelli, A., Bertolo, G., Archer, G.P., Kennedy, C.J., Bone, S., Blond, G., Contreras-Lopez, E., and Champion, D. 1999a. Modification of glass transition temperature through carbohydrates additions Effect upon colour and anthocyanin pigment stability in frozen strawberry juices. Food Res. Int. 32, 441 146. 

Figure FI. 3.4 shows HPLC chromatograms for anthocyanidins generated from acid hydrolysis of concord grape and strawberry juices. Extraneous peaks may be present because of incomplete hydrolysis, and degradation and polymerization of the labile aglycons even more of a problem. For acylated anthocyanins, higher yields of anthocyanidins will be achieved if the sample is first saponified (see Basic Protocol 3) and then subjected to acid hydrolysis (see Basic Protocol 2).

Schieberle, P. and Hofmann, T. 1997. Evaluation Of the character impact odorants in fresh strawberry juice by quantitative measurements and sensory... 

Finally, the addition of cheaper juices to more expensive ones can usually be detected and measured using techniques appropriate to the likely components. For example, the addition of elderberry to strawberry juice can readily be detected by examining the anthocyanins present using HPLC and comparing them with standards. 

Although a combination of product quality and cost considerations will dictate the methods used for bulk processing of fruit juices, there are instances where the flavour components present in the juice at e vulnerable to any form of heating din ing concentration. Strawberry juice is perhaps the best example of this, being one of the most heat sensitive of fruits, and it works well with alternative processes for concentration such as freeze-concentration and hyperfiltration. 

While the shortcakes are cooling, combine all the strawberry ingredients in a large mixing bowl. Let stand for about 30 minutes, until the strawberry juices come out. (You may need to drain the mixture before placing it on the shortcakes.)... 

Silk Soymilk products (silksoymilk.com)—include blueberry, raspberry, cherry, and strawberry juice/puree in nutrient-fortified soy milk yogurt with six active cultures... 

Rwabahizi, S. and Wrolstad, R.E. 1988. Effects of mold contamination and ultrafiltration on the color stability of strawberry juice and concentrate. J. Food Sci. 53(3) 857—861, 872. 

The concentrations and OAV of odorants detected in strawberry juice are given in Table 6.41. To confirm that these compounds are actually the key aroma compounds, they were dissolved in a model juice matrix of pH 3.5 [75]. Sensory evaluations showed that the intensities of the fruity, sweet and green odour notes of the model were nearly as high as those of the natural juice. Only the fresh strawberry note was somewhat lower in the model. 

Rodrigo, D., Loey, A. van., and Hendrickx, M. 2007. Combined thermal and high pressure color degradation of tomato puree and strawberry juice. Journal of Food Engineering 79 553-560. 

White grape juice Pineapple juice Strawberry juice Lemon juice Orange juice Raspberry juice Vegetables, fresh or frozen Sweet corn (fresh)... 

Torreggiani, D., Fomi, E., Guercilena, I. et al. 1999. Modification of glass transition temperature through carbohydrates additions Effect upon color and anthocyanin pigment stability in frozen strawberry juices. Food Research International 32 441-446. 

The first step in this investigation was to isolate the pigment from strawberry juice by the method described by Sondheimer and Kertesz (11). This method involved the saturation of the juice with salt and extraction with 1-butanol, then concentration of the butanol extract under vacuum and in a nitrogen atmosphere. The anthocyanin concentrate was then taken up with hydrochloric acid in anhydrous methanol, precipitated with ether, dissolved in 0.01% hydrochloric acid, and saturated with picric acid. The anthocyanin picrate crystallized out of this solution upon storage at 0° C. as lustrous reddish bronze prisms which were further purified by recrystallization. 

For this reason the basic coloring material, wherever extracted pigment was used, was the water-soluble portion of the ether-precipitated concentrate of the 1-butanol extract of strawberry juice (St B). This material has not been further purified by picration and crystallization. It contains essentially all the anthocyanin coloring pigments in strawberries free from the natural sugars. It was found, however, that the reactions of the water-soluble portion and the recrystallized material were not significantly different. 

The natural strawberry material was prepared from a good commercial grade of frozen Blakemore strawberry juice. Its history showed that it had never been pasteurized, was pressed on stainless steel equipment, and had not been otherwise abused. The frozen juice was slowly thawed and the early free-run juice was collected at a soluble solids content of 22% (St J). 

The color of some of this concentrated strawberry juice was destroyed by autoclaving at 121° C. (250° F.) for 1 hour. This material (St JD) was brown colored, slightly turbid, and identical with the concentrate (St J), except for the damage done by the heat treatment. 

Some of the concentrate was diluted back to single-strength strawberry juice and saturated at room temperature with sucrose. This mixture (St S) closely simulates the composition of a finished strawberry preserve. 

The nitrogen content of all the materials added to the strawberry juice was reported by a consulting analytical laboratory to contain a trace or no nitrogen as determined by the Dumas method. 

St B. Water-soluble portion of the ether-precipitated butanol-extracted pigment of strawberry juice. 

St J. A representative sample of commercial strawberry juice, concentrated by freezing. 

St S. Single-strength strawberry juice made up to 67% solids with sucrose. 

Figure 1. Change in Spectra of Buffered Solution of Strawberry Juice Pigment Concentrate with Change in pH at Constant Concentration...

The importance of maintaining constant buffer salt concentration is graphically illustrated in Figure 4, which shows an increase in rate of pigment loss when increments of sodium citrate were added to strawberry juice (St J). However, this detrimental effect was not observed when sodium citrate was added to extracted pig-... 

Figure 3. Effect of Change in pH on Rate of Color Loss in Buffered Solutions of Strawberry Juice Concentrate...

Figure 4. Effect of Sodium Citrate on Rate of Color Loss in Frozen and Thawed Strawberry Juice...

Table I. Effect of Ascorbic Acid in Presence of Iron and Copper on Rate of Color Loss in Strawberry Juice (St J)...

Table I shows the relationship between rate of pigment loss in single-strength strawberry juice and the metallic ion content with and without ascorbic acid.

The source of the carbohydrate that might enter into such a reaction need not necessarily be an added one. Indeed, there is evidence that the source material is already present in the strawberry juice itself. Figure 8 shows the effect of the addition of concentrated strawberry juice and heat-damaged strawberry juice upon pigment loss. The juice must contain an agent or agents, which are increased upon... 

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