2009_Book_FoodChemistry

816 18 Fruits and Fruit Products
Table 18.4. Proximate composition of shell-nut fruit (as % of fresh edible portion)
Fruit Mois- N-Com- Lipids Available Ash Dietary
ture pounds carbo- fiber
(N × 5.3) hydrates
Cashewnut 4.0 16 42.2 30.5 2.9 2.9
Peanut 5.0 25.3 47.5 7.5 2.2 11.7
Hazelnut 5.2 12.0 66.0 10.5 2.5 8.2
Pistachio 5.9 17.6 53.5 11.6 2.7 10.6
Almond 5.7 20.5 56.0 5.4 2.7 13.5
Walnut 4.4 15.0 64.4 10.6 2.0 6.1
Fig. 18.2. Enzyme patterns of some strawberry species (Fragaria sp.) and(Fragaria ananas) obtained by PAGE
disc gel electrophoresis. Large pore concentrating gel pH 6.7, small pore separating gel, pH 8.9. 1 Peroxidase:
incubation with o-toluidine/H 2 O 2 at pH 7. 2 Esterase: incubation with α-naphthylacetate at pH 7, the released
α-naphthol is diazotized and then coupled with p-chloroaniline. 3 Malate-dehydrogenase: incubation with malate,
nitro-blue-tetrazolium chloride and NAD at pH 7.5. (according to Drawert et al., 1974)
Table 18.5. Free amino acids in fruits (as % of total free amino acids)
Fruit Asp Asn Glu Gln Ser Thr Pro Ala Abu b His Arg Pip c
Apple (juice) 21 17 15 10 3 2 7 5
Pear (juice) 10 9 10 11 2 14 9 3
Grapes 3 13 6 31 9 6 27
Currant 7 17 24 5 8 17 12
black
Orange a 7–115 20–188 6–93 3–63 4–37 8–79 3–26 4–73 0–23
Grapefruit a 34–99 8–90 310 10 4–27 76 20–45
Lemon a 19–60 6–35 12–28 1–31 4–20 25–106
Banana 5–10 15 10–15 5–10 10–15 5–10
a Values in mg/100ml juice.
b γ-Aminobutyric acid.
c Pipecolinic acid.