The pistachio is regarded as a relevant source of biologically active components that, compared to other nuts, possess a healthier nutritional profile with low-fat content composed mainly of monounsaturated fatty acids, a high source of vegetable protein and dietary fibre, remarkable content of minerals, especially potassium, and an excellent source of vitamins, such as vitamins C and E. A rich composition in terms of phytochemicals, such as tocopherols, carotenoids, and, importantly, phenolic compounds, makes pistachio a powerful food to explore its involvement in the prevention of prevalent pathologies.
1. Nutritional Value of Pistachios
The pistachio is a low-water (3–6%) and nutritionally rich nut mainly because of its high fat (48–63%) and protein concentration (18–22%), together with the dietary fibre (8–12%;
Table 1)
[14,15][1][2]. In fact, the daily intake of nuts recommended (1.5 oz equivalent to 42.5 g; 4) in the form of pistachios is approximately 15% of the Dietary Reference Intake (DRI) for proteins, 11–18% of DRI for male and female respectively for dietary fibre, and 24% of DRI for fat. Lipids, although present in great amounts, have an equilibrated content of mono- (56–77%) and polyunsaturated (14–33%;
Table 1) fatty acids, that may help to reduce LDL-cholesterol and hence the coronary heart disease risk
[2,16,17][3][4][5].
Table 1. Composition (g/100 g) in nutrients of dry roasted nuts. Source: USDA National Nutrient Database for Standard Reference (2020). MUFA: monousaturated fatty acids; SFA: saturated fatty acids; PUFA: polyunsaturated fatty acids.
g/100 g |
Pistachio |
Walnut |
Almond |
Hazelnut |
[23][9] (
Table 2).
Table 2.
Total phenolic content and antioxidant activities of different varieties of pistachios.
Type of Pistachio |
Status of Pistacho |
TPP |
Antioxidant Assay |
Value of Antioxidant Capacity |
References |
Water |
1.85 |
Larnaka (Spanish cultivar) |
Natural | 4.39 |
2.41 |
2.52 |
4900 mg/Kg fw |
ORAC |
330 mmol of TE/Kg |
[ | 24 | ] | [10] |
Energy (Kcal) |
572 |
643 |
598 |
646 |
|
|
|
DPPH |
35 mmol of TE/Kg |
|
Lipids |
45.82 |
60.71 |
52.54 |
62.40 |
Kastel (Spanish cultivar) |
Natural |
1600 mg/Kg fw |
ORAC |
89 mmol of TE/Kg |
[24] | [10] |
SFA |
5.64 |
5.36 |
4.10 |
4.51 |
|
|
|
DPPH |
13 mmol of TE/Kg |
|
PUFA |
13.35 |
44.18 |
12.96 |
8.46 |
Kerman (Spanish cultivar) |
Natural |
1900 mg/Kg fw |
ORAC |
61 mmol of TE/Kg |
[24] | [10] |
MUFA |
24.53 |
8.37 |
33.08 |
46.61 |
|
|
|
DPPH |
10 mmol of TE/Kg |
|
C16:0 |
8.0–13.0 |
6.0–8.0 |
4.0–13.0 |
4.0–9.0 |
Uzun (Turkish cultivar) |
Natural |
26.2 mg/100 g fw |
DPPH |
8.05 μmol of TE/g |
[27] | [11] |
C18:0 |
0.5–2.0 |
1.0–3.0 |
|
Roasted | 2.0–10.0 |
1.0–4.0 |
32.4–42.4 mg/100 g fw |
DPPH |
C16:1 |
0.5–1.0 |
0.1–0.2 |
0.2–0.6 |
0.1–0.3 |
C18:1 |
45.0–70.0 |
13.0–21.0 |
48.0–80.0 |
66.0–85.0 |
C18:2 |
16.0–37.0 |
54.0–65.0 |
15.0–34.0 |
5.7–25.0 |
C18:3 |
0.1–0.4 |
13.0–14.0 |
N.D. |
0.0–0.2 |
Proteins |
21.05 |
14.29 |
20.96 |
15.03 |
Carbohydrates |
28.28 |
17.86 |
21.01 |
17.60 |
Fiber |
10.30 |
7.10 |
10.90 |
9.40 |
Sugars |
7.74 |
3.57 |
4.86 |
4.89 |
Dry roasted pistachios have a lower fat content (45.82 g/100 g) than other nuts (
Table 1), mainly monounsaturated fatty acid (24.53 g) followed by polyunsaturated fatty acid (13.35 g) and saturated fatty acid (5.64 g). Of the fatty acids, oleic is the main monounsaturated fatty acid (MUFA) in pistachios followed by linoleic acid (C18:2), which represents more than half of the total fatty acid content (<60 g) (
Table 1). Pistachio shows a similar lipid profile to almonds and hazelnuts while walnut fat is headed by linoleic acid (54.0–65.0 g/100 g) followed by oleic (C18:2) and linolenic (C18:3) acids with similar contents. Pistachios are also a worthy source of vegetable protein (about 21%) as almonds (21%), and higher than other nuts, such as hazelnuts and/or walnuts. The amount of total carbohydrates is low to moderate (28%), but pistachios are rich in dietary fibre, mainly insoluble fibre (about 10% versus less than 1% of soluble fibre).
Pistachio also contains a remarkable content of minerals, such as magnesium, calcium, potassium, and phosphorus, and is documented as an important dietary source of potassium (1025 mg/100 g versus ~700 mg of almond and hazelnut or 450 mg of walnut per 100 g dry roasted nuts). Pistachios are rich in vitamins, especially vitamins C (5.60 mg/100 g) and E (mainly as γ-tocopherol) (2.17 g/100 g). Others, such as vitamin A, vitamin B (except B12), vitamin K, and folate, are existent in pistachios, which could contribute to their respective Recommended Dietary Allowance (RDA).
2. Antioxidant Phenolic Composition of Pistachios
Nutrient databases, like the Phenol-Explorer and the flavonoid and proanthocyanidin databases (USDA)
[21,22][6][7] report the content of polyphenol of many foods. Furthermore, the concentration of various families of phenolic components in nuts, including pistachio, as well as their antioxidant capacity and evidence for healthy effects have been recently
summar
evieweized
[1,23][8][9].
Walnuts, pecans, and pistachios are the kinds of nuts with the higher phenolic amounts, on the contrary almonds, peanuts, and hazelnut present lower levels (e.g.,
[1,23][8][9]. A variety-dependent content of total polar phenolics (TPP) is found in pistachios, ranging from 1600 mg/kg for the Kastel cultivars to more than three times more, 4900 mg/kg for Larnaka. As reported, polar phenolic components can be grouped into different families. Flavanols being the most abundant phenolics found (about 90% of total, from 1500 mg/kg to 4500 mg/kg), whereas the Kastel and Larnaka cultivars showed the lowest and highest concentrations, respectively
[24][10]. Other families, e.g., anthocyanins (from 54 to 218 mg/kg), flavonols (from 76 to 130 mg/kg), flavanones (from 12 to 71 mg/kg), and gallotannins (from 4 to 46 mg/kg), are also measured. These findings are similar to those reported by Alasalvar & Bolling
[1][8] or Chang et al.
9.76–11.5 μmol of TE/g |
[ |
27 |
] |
[ |
11 |
] |
Ohadi (Turkish cultivar) |
Natural |
9.23–10.55 mg/Kg GAE |
DPPH |
4.34–5.56 mmol TE/Kg |
[28] | [12] |
|
|
|
ABTS |
4.11–5.95 mmol TE/Kg |
[28] | [12] |
|
Roasted |
10.35–11.23 mg/Kg GAE |
DPPH |
3.53–6.32 mmol TE/Kg |
[28] | [12] |
|
|
|
ABTS |
5.80–7.35 mmol TE/Kg |
[28] | [12] |
Uzum (Turkish cultivar) |
Natural |
9.19–11.46 mg/Kg GAE |
DPPH |
7.16–13.58 mmol Trolox/Kg |
[28] | [12] |
|
|
|
ABTS |
15.69–28.28 mmol Trolox/Kg |
[28] | [12] |
|
Roasted |
10.46–12.73 mg/Kg GAE |
DPPH |
13.5–18.00 mmol Trolox/Kg |
[28] | [12] |
|
|
|
ABTS |
26.81–35.86 mmol Trolox/Kg |
[28] | [12] |