Strawberries from juice

The anthocyanin stabilities of grape-marc, elderberry, and black currant extracts were lower in all sucrose (100 g/L)-added systems as compared to the controls at pH values of 3, 4, and 5, whereas the brown index did not change with the addition of sugar. On the contrary, a protective effect of 20% sucrose added to frozen crowberries and strawberries was reported and the stabilities of anthocyanin juices from aronia were higher in syrups than in diluted extracts. Roselles pre-... 

Other assays have been used to evaluate the antioxidant activity against H202 of several plant-based products, namely, fruit juices from different cultivars of berries (Wang and Jiao 2000), fractions rich in phenolics isolated from the aqueous by-products obtained during the milling of oil palm fruits (Balasundram and others 2005), cherry laurel fruit and its concentrated juice (Liyana-Pathirana and others 2006), and strawberries and blackberries treated with methyl jasmonate, allyl isothiocyanate, essential oil of Melaleuca alternifolia, and ethanol (Chanjirakul and others 2007). 

Red cabbage as a colorant source has been studied for many years. As of 1990 at least one firm has introduced San Red RC, the first commercially available food color derived from red cabbage. The color can be used alone or in combination with other colors to create strawberry, cherry, raspberry, and blueberry tones. By way of proprietary technology, the new dye is claimed to be free of flavor and odor defects, which in the past have been associated with red cabbage. The dye is pH dependent. The color tones move toward blue-red as the pH value increases. San Red RC ranks between cochineal and grape juice in percent or color retention. 

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).

In 1998, PDP collected samples of apple juice, cantaloupe, grape juice, green beans, orange juice, pears, spinach, strawberries, sweet potatoes, tomatoes, winter squash, com symp, milk, and soybeans. A total of 8500 samples were collected. Most of these were from fmits and vegetables (7017) with lower numbers of samples collected for whole milk (595), soybeans (590) and com symp (298). The majority of samples (84 percent) was of domestic origin. Overall, 45 percent of the samples contained no detectable residue while 26 percent contained one residue and 29 percent contained more than one residue. Residues exceeding the tolerance level were detected on 0.15 percent of the samples. In another 3.7 percent of the samples, residues of pesticides were detected on commodities for which no tolerances of the pesticides were established (USDA, 2000). 

It has been known for decades that heat is one of the most destructive factors of anthocyanins in berry fruit juices (Jackman et al., 1987a). With strawberry preserves, it was shown as early as 1953 that the half-life time was 1 h at 100°C, 240 h at 38°C and 1300 h at 20°C. In a storage experiment with concentrates and dry powder of elderberry extracts, the stability increased 6-9 times when the temperature was reduced from 20°C to 4°C (Zajac et al., 1992). Anthocyanin degradation in anthocyanin solutions increased from 30% to 60% after 60 days when storage temperatures were increased from 10°C to 23°C (Cabrita et al., 2000). High-temperature short-time processing is recommended for maximum anthocyanin retention of foods containing anthocyanins (Jackman and Smith, 1996). 

Other fruit spirits are distilled from fresh or frozen fruits or their juices (blueberries, raspberries, strawberries, currants, apricots, peaches and others) while adding alcohol. Pomaceous fruit spirits are made from fresh fermented apples or other pomaceous fruits, from the whole fmit or its juices without the addition of sugar-containing substances, sugar or alcohol of another kind with a minimum alcohol content of approx. 38% by vol. 

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). 

Cltrlo sold—Acidum eUricum (U. S., Br.)—-f Aq—19 l + 18—is best considered in ibis place, although its constitution is different from that of tartaric acid. It exists in the juices of many fruits—lemon, strawberry, etc. 

Fruit Juice concentrates vary widely in price because of differences in raw product cost and processing yield. For example, wholesale 1978 prices for Pacific Northwest produced concentrates varied from 6.25 per gallon for apple and pear to 35> T5, and 110 per gallon for strawberry, blackberry, and black raspberry concentrates, respectively (. ). The readily available, low priced concentrates are obvious potential adulterants for more expensive concentrates and methods are needed for their detection. 

Ethyl butanoate 6 12 2 116.16 H3C-(CH2)2-C00C2H5 0.879 121 2915 60 [105-25-4] 26 apple, banana, pear, strawberry, juice from citrus bruit... 

Ethyl hexanoate CsH j02 144.21 H3C-(CH2)4-C00C2H5 0.871 168 2915 90 [123-66-0] 60 pineapple, strawberry, guava, clove, rum, juice from citrus fruit... 

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