Apple Juice Composition: Sugar, Nonvolatile Acid, and Phenolic Profiles

1988 ◽  
Vol 71 (4) ◽  
pp. 789-794 ◽  
Author(s):  
Hyoung S Lee ◽  
Ronald E Wrolstad

Abstract Apples from Michigan, Washington, Argentina, Mexico, and New Zealand were processed into juice; the 8 samples included Golden Delicious, Jonathan, Granny Smith, and Mcintosh varieties. Liquid chromatography was used for quantitation of sugars (glucose, fructose, sucrose, and sorbitol), nonvolatile acids (malic, quinic, citric, shikimic, and fumaric), and phenolics (chlorogenic acid and hydroxymethylfurfural [HMF]). Other determinations included pH, °Brix, and L-malic acid. A number of compositional indices for these authentic juices, e.g., chlorogenic acid content, total malic - L-malic difference, and the HMF: chlorogenic ratio, were at variance with recommended standards. The phenolic profile was shown to be particularly influenced by gelatin fining, with peak areas decreasing by as much as 50%. The L-malic: total malic ratio serves as a better index for presence of synthetic malic acid than does the difference between the 2 determinations. No apparent differences in chemical composition could be attributed to geographic origin.

1983 ◽  
Vol 66 (6) ◽  
pp. 1517-1520 ◽  
Author(s):  
Randall H Evans ◽  
Anton W Van Soestbergen ◽  
Karen A Ristow

Abstract An organic acid profile provides valuable information regarding authenticity of apple juice. The presence of D-malic acid is a clear indication of adulteration because this isomer does not occur naturally. Fumaric and citric acid levels above trace amounts are also inconsistent with pure apple juice; therefore, measurement of these organic acids may also be used as an authenticity check. Citric acid, total malic acid, and fumaric acid were determined in a single scan by liquid chromatography (LC) for 30 known pure apple juice samples. The L-isomer of malic acid was measured by an enzyme-specific method, and the D-isomer was calculated as the difference between total malic acid and L-malic acid.


2021 ◽  
Vol 38 ◽  
pp. 00051
Author(s):  
Evgeniya Karpova ◽  
Sayfiddin Kh. Davlatov ◽  
Alexander Chernonosov

For the first time, the phenolic profile of poorly studied Siberian species of the genus Myricaria Desv. Myricaria longifolia (Willd.) Ehrenb. was investigated by HPLC and LC-MS/MS in comparison with that of wide-ranging species M. bracteata Royle. 65 quantitative parameters of the phenolic profiles were processed by ANOVA and principal component analysis (PCA). The results suggest that the distinction between the species is mainly determined by the variance in total flavonoids and free quercetin in the leaves. Free gallic and ferulic acids, hyperoside and total phenolics in aqueous ethanol extract, as well as kaempferol and rhamnazin in the hydrolyzed extract contributed to the difference between the species. The significant differences justify the positions of these species in two individual series of the genus Myricaria established before. The statistical analysis of the biochemical data allowed us to identify both the characters that determined the distinction between species, and indicators of heterogeneity of the species that varies abnormally (the concentrations of isorhamnetin and rhamnazin, and their ratio).


2007 ◽  
Vol 90 (5) ◽  
pp. 1346-1353 ◽  
Author(s):  
Diego L García-González ◽  
María Viera-Macías ◽  
Ramón Aparicio-Ruiz ◽  
Maria T Morales ◽  
Ramón Aparicio

Abstract The difference between theoretical and empirical triglyceride content is a powerful tool to detect the presence of any vegetable oil in olive oil. The current drawback of the method is the separation between equivalent carbon number ECN42 compounds, which affects the reliability of the method and, hence, its cutoff limit. The determination of the triglyceride profile by liquid chromatography using propionitrile as the mobile phase has recently been proposed to improve their quantification, together with a mathematical algorithm whose binary response determines the presence or absence of hazelnut oil. Twenty-one laboratories from 9 countries participated in an interlaboratory study to evaluate the performance characteristics of the whole analytical method. Participants analyzed 12 samples in duplicate, split into 3 intercomparison studies. Statistically significant differences due to the experimental conditions were found in some laboratories, which were detected as outliers by use of Cochran's and Grubbs' tests. The relative standard deviations (RSD) for repeatability and reproducibility were determined following the AOAC Guidelines for Collaborative Studies. The analytical properties of the method were determined by means of the sensitivity (0.86), selectivity (0.94), and reliability (72) for a cutoff limit of 8 (probability 94).


1992 ◽  
Vol 262 (2) ◽  
pp. G351-G358
Author(s):  
R. Zhang ◽  
S. Barnes ◽  
R. B. Diasio

Mechanisms responsible for the difference in the relative amounts of taurine- and glycine-conjugated bile acid N-acyl amidates (Tau/Gly ratio) are not fully understood. In the present study, the stability of taurine- and glycine-conjugated bile acid N-acyl amidates during intestinal transit and absorption was examined to investigate the contribution of intestinal deconjugation to the Tau/Gly ratio in rat bile. Radiolabeled chenodeoxycholic acid (CDC) and its N-acyl amidates with glycine (CDC-Gly) or taurine (CDC-Tau) were introduced into the lumen of the upper small intestine in the biliary fistula rats, and radioactive metabolites in bile, blood, urine, and tissues were identified and quantitated by high-performance liquid chromatography. Results indicated that 1) extensive deconjugation of CDC-Gly occurs during intestinal absorption; 2) CDC-Tau is recovered in bile largely intact; and 3) newly synthesized CDC-Tau and CDC-Gly are formed in a ratio of less than 2:1 after administration of [14C]-CDC. In summary, the present study demonstrates that resistance of taurine-conjugated bile acid N-acyl amidates to hydrolysis in the intestine, rather than a difference in synthesis of taurine- and glycine-conjugated N-acyl amidates in liver, may account for the high Tau/Gly ratio in rat bile.


2014 ◽  
Vol 86 (2) ◽  
pp. 881-888 ◽  
Author(s):  
MARIANA PIANA ◽  
ALINE A. BOLIGON ◽  
THIELE F. DE BRUM ◽  
MARINA ZADRA ◽  
BIANCA V. BELKE ◽  
...  

The antioxidant capacity of the crude extract and fractions ofTabernaemontana catharinensis fruits and branches, was evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and the content of polyphenols, flavonoids, alkaloids and condensed tannins were determined by the spectrophotometric method. The ethyl acetate fraction of the fruits and the n-butanol fraction of the branches showed IC50 of 181.82 µg/mL and 78.19 µg/mL, respectively. All fractions were analyzed by high performance liquid chromatography (HPLC), in the branches were quantified chlorogenic acid in the chloroform (8.96 mg/g), ethyl acetate (4.31 mg/g) and n-butanol (3.33 mg/g) fractions; caffeic acid in the ethyl acetate (5.24 mg/g) and n-butanol (1.81 mg/g); gallic acid (0.52 mg/g) in the n-butanol. In the fruits, chlorogenic acid in the chloroform (1.67 mg/g); rutin in the ethyl acetate (3.45 mg/g) and n-butanol (8.98 mg/g) fractions. The present study showed that these quantified compounds can contribute to antioxidant capacity which was higher in the branches than in the fruits.


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