In some fruits

Carotenoids from fruits and vegetables can exist as protein-carotenoid complexes (as in the case of green leaf vegetables), crystals (as in carrots or tomatoes), or in oil solution (as in mango and papaya) (West and Castenmiller 1998). Carotenoids commonly found in human blood are lutein, zeaxanthin, (3-cryptoxantliin, lycopene, 13-carotene, and a-carotene. The content of some carotenoids in some fruits and vegetables is shown in Table 7.3. 

Table 7.3. The content of some carotenoids in some fruits and vegetables...

Table III. Dietary Required Amino Acids (mg/100 g Fresh Fruit) in Some Fruits...

Berger, R.G., Drawer , F., Kollmannsberger, H., Nitz, S. (1985) Natural occirrrence of unde-caenes in some fruits and vegetables. J. Food Sci. 50 1655-1656, 1667. 

There is no doubt that caffeic acid is the cinnamate that occurs most extensively, and the various caffeoylquinic acids (CQA) and dicaffeoylquinic acids (diCQA) are the most ubiquitous conjugates. Usually the 5-isomers dominates, but in some fruit and brassicas the 3-isomer is prevalent. Because of the quantity commonly consumed, coffee... 

T Philip, T-S Chen. Development of a method for the quantitative estimation of provitamin A carotenoids in some fruits. J Food Sci 53 1703-1706, 1988. 

In natural tissues, carotenoids generally occur as complex mixtures of many substances in orange juice, for instance, more than 50 carotenoids were identified. A survey of the carotenoid content in some fruits and vegetables is given in Refs. 19 and 20. Differences due to variety, site, and maturity must be considered. 

Sterols, which are very abundant in some fruits, can be removed by precipitating them in different solvents. The unsaponifiable matter is dissolved in a minimum volume of methanol, petroleum ether, or acetone. The precipitation is completed overnight at — 20°C following centrifugation, the sterol-free supernatant is used for analysis (5). 

Phosphoric acid is the only inorganic acid to be widely used in food preparations as an acidulant. It does, however, occur naturally in the form of phosphates in some fruits, for example, limes and grapes. In the soft drinks industry its use is confined almost entirely to cola-flavoured carbonated beverages, where its... 

Benzoic acid occurs naturally in some fruits and vegetables, notably in cranberries, where it occurs in amounts of the order of 0.08% m/m (Fellows Esselen, 1955). It is also found in some resins, chiefly in gum benzoin (from Styrax ben-zoia), and in coal tar. Commercially available benzoic acid is produced by chemical synthesis. 

Off-flavors and atypical odors have been developed in some fruits, particularly tangerines and limes. 

Haight, G.P. (1951) Solubility of methyl bromide in water and in some fruit juices. Ind. Eng. Chem. 43, 1827-1828. 

Sugar alcohols occur in some fruits and are produced industrially as food ingredients. 

Table 6-6 Anthocyanidins Occurring in Some Fruits and Vegetables...

Capillary gas chromatographic investigation of diastereoisomeric derivatives revealed that in some fruits, such as passion fruits (9) and blackberries (17), secondary alcohols and their esters are contained in almost optically pure form. On the other hand corn (Zea mays) contains aliphatic secondary alcohols as mixtures of enantiomers the ratios depend upon the chain lengths of the alcohols. Heptan-2-ol is present mainly as (R)-enantiomer with increasing chain length the proportion of (S)-enantiomer increases. A similar distribution has been determined in coconut (Figure 4). 

Sorbitol or D-Glucitol is a white odorless nontoxic powder, with a sweet taste. It contains 0.5 mol of water of crystallization and melts at 97—98°C. Anhydrous sorbitol melts at 110°C. It is very hygroscopic, slightly soluble in methanol and ethanol, and insoluble in ether and most nonpolar solvents [119], The occurrence of sorbitol in nature is not widespread, but it is found in some fruits [120]. 

Table 7.2 shows volume changes in some fruit products and water-sucrose solutions. It can be observed that highly concentrated sucrose solutions do not show expansion. 

It has for some time been evident that fruit softening can not in all cases be attributed solely to the action of endo-D-galacturonanase (EDG). In some fruits, including muskmelon (3,26), plum ( ), and strawberry (20-22), softening occurs in the apparent absence of this enzyme. Apple fruit contain exo-D-galacturonanase... 

Nunes, G. S., Alonso, R. M., Ribeiro, M. L., and Barceld, D., Determination of aldicarb, aldicarb sulfoxide, and aldicarb sulfone in some fruits and vegetables using high-performance liquid chromatography-atmospheric pressure chemical ionization mass spectrometry, J. Chromatogr. A, 888, 113-120, 2000. 

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