This study gives an overview on the nutritional value, bioactive compounds and antioxidant activity (ABTS and FRAP) of Bronte’s pistachio (Pistacia vera, L., cv. Bianca) from Sicily (Italy). Bronte’s pistachios are rich in fat, protein, dietary fiber, trace elements (Fe, Zn, Cu, Mn) and minerals (Ca, P, K, Mg, Na). Lipids mainly consist of MUFA (33.8 g/100g), primarily oleic acid (32.4 g/ 100g); PUFA is mostly represented by linoleic acid (7.49 g/100g). Bronte’s pistachios are also a valuable source of bioactive compounds such as total polyphenols (501.5 mg/100g), lutein (1.26 mg/100g), β-carotene (0.18 mg/100g), γ-tocopherol (19.2 mg/100g) and phytosterols (134.4 mg/100g). Among phytosterols, the main is β-sitosterol (86% of total content), followed by Δ5-avenasterol (6.3%). Phytic acid content is 1763 mg/100g; Ins(1,2,4,5,6)P5 and Ins(1,2,3,4,5,)P5 have been detected too (31 mg/100g and 10 mg/100g, respectively). The antioxidant activity was determined both in hydrophilic and lipophilic fraction of pistachios, showing >80% of the total antioxidant activity in the hydrophilic, predominately due to phenolic compounds.
In the Mediterranean area an intense food trade has taken place for centuries. Pistachios (Pistacia vera, L.) represent an example of the food exchanged in this area, so for a long time pistachios have become an integral part of the Mediterranean food pattern. Nowadays the consumers’ interest in pistachios is focusing on the high content of dietary fibre, minerals and trace elements, monounsaturated fatty acids and valuable bioactive compounds. During the last decades nuts have attracted the attention for their potential health benefits; strong relationships between nut/nut oil-containing diet and protection against cardiovascular diseases [
Most of the Italian pistachio area is concentrated in few territories in the eastern Sicily on the slopes of the Etna volcano, Bronte representing the main production area. The Bronte’s pistachio is mainly used for the bagged meat and confectionery industry and to produce pistachio cream, sprinkles and ice-cream. In recent years Bronte’s pistachio has also received the attribution of Protected Designation of Origin (PDO) by the European Union (EU 21-2010), a quality label referred to zone of production (Bronte, Adrano and Biancavilla). The aim of the present study was to evaluate the content of proteins, lipids, carbohydrates, minerals (Ca, P, K, Mg, Na), trace elements (Fe, Zn, Cu, Mn) and dietary fiber of Bronte’s pistachios (Pistacia vera, L., cv. Bianca). Moreover, the content of bioactive compounds such as total polyphenols, carotenoids, tocopherols, phytosterols, phytic acid and the antioxidant activity was determined to evaluate the nutritional value of Bronte’s pistachio.
Italian Pistachios (Pistacia vera, L., cv. Bianca) from Bronte (Sicily, Italy) were obtained from the “Consortium for Bronte Pistachio Protection (PDO)”, according to the corresponding product specification, e.g. cultivation altitude, crop management (hand-harvesting, sun-drying process). A total of 9 kg of pistachios grown in six farms of the Bronte’s area were delivered to laboratory raw and unshelled, packed in vacuum sealed storage bags. Equal amounts of pistachio nuts were randomly grouped into six batches and stored in refrigerator at +4˚C until analysis. Each batch was analyzed in triplicate.
Moisture, protein, lipid and ash were determined according to AOAC methods [
Samples were analyzed for mineral (Ca, Mg, Na, K, P) and trace element (Fe, Zn, Cu, Mn) contents by ICP-OES (Optima 3200XL―Perkin-Elmer) after liquid ashing (4 mL HNO3 + 1 mL H2O2) of the samples in a microwave digestion system (Milestone, 1200 Mega). Standard Reference Materials: Cabbage (IAEA-359, International Atomic Energy Agency Reference Materials Group) and Haricots vert (BCR 383, Community Bureau of Reference, Brussels) were analyzed as a check on the accuracy of the analysis.
Total dietary fiber and fractions, soluble and insoluble, were determined by method of Prosky et al. [
Phytic acid and inositolphosphates content were determined by HPLC following the method of Schlemmer et al. [
Fatty acids were methylated according to the method by Slover and Lanza [
Total polyphenols content was determined following the Folin-Ciocalteau method [
The lipophilic bioactive compounds were determined in the oil fraction of pistachios. Whole, unshelled pistachios were grounded in a water cooler mixer to a fine powder in order to obtain a homogeneous representative sample. A cold solvent extraction method of pistachio oil was performed to preserve bioactive molecules from degradation [
Carotenoid (violaxanthin, lutein and its isomers, β-carotene) content in pistachio oil was quantified by HPLC/ PAD according to the method by Pilar Cano [
The pistachio oil was analyzed by LC/MS-MS (AGILENT 1200 series quaternary pump coupled with an AGILENT 6410 triple quadrupole mass spectrometer) for tocopherols (T) and tocotrioenols (T3): α-tocopherol, α-tocotrienol, β-tocopherol, β-tocotrienol, γ-tocopherol, γ-tocotrienol, δ-tocopherol and δ-tocotrienol content was determined without saponification [
Phytosterols were extracted from pistachio oil after saponification, as reported in literature methods [
Antioxidant activity of Bronte’s pistachio was assessed both on hydrophilic and lipophilic fractions. The hydrophilic fraction was extracted from fine grounded pistachios by CH3OH/H2O (1/1), the residue was utilized for the extraction of the lipophilic fraction, carried out by acetone [
ABTS assay: the antioxidant activity was evaluated by ABTS method as described by Re et al. [
FRAP (Ferric reducing antioxidant power) assay: the method was applied only to the hydrophilic extract. The antioxidant activity was expressed as mmol Fe2+ equivalents/kg [
All experimental data are presented as the Mean ± Standard Deviation of the six analysed pistachio’s batches. The linearity of responses of the antioxidant activity analysie was determined using Pearson’s correlation coefficient (r).
The overall nutrient composition, total dietary fiber and its fractions, minerals and trace-elements, fatty acids content of Bronte’s pistachio are reported in
The average protein content detected in Bronte’s pistachio in this study was fairly high compared with other
Bronte Pistachio | ||
---|---|---|
Proximate | ||
Moisture | g/100g | 5.34 ± 0.4 |
Ash | g/100g | 3.06 ± 0.08 |
Protein | g/100g | 24.5 ± 0.4 |
Lipid | g/100g | 49.0 ± 1.2 |
Carbohydrates | g/100g | 2.8* |
Dietary fiber | g/100g | 15.3 ± 0.32 |
Soluble | g/100g | 2.2 ± 0.14 |
Insoluble | g/100g | 12.3 ± 0.21 |
Minerals | ||
Ca | mg/100g | 114 ± 12 |
P | mg/100g | 416 ± 25 |
K | mg/100g | 962 ± 33 |
Mg | mg/100g | 121 ± 7.5 |
Na | mg/100g | tr |
Trace Elements | ||
Fe | mg/100g | 4.5 ± 0.28 |
Zn | mg/100g | 2.1 ± 0.12 |
Cu | mg/100g | 1.2 ± 0.05 |
Mn | mg/100g | 0.3 ± 0.02 |
Fatty acids | ||
SFA | ||
C14:0 | g/100g | 0.044 ± 0.004 |
C16:0 | g/100g | 4.36 ± 0.09 |
C18:0 | g/100g | 0.92 ± 0.10 |
C20:0 | g/100g | 0.08 ± 0.004 |
C22:0 | g/100g | 0.04 ± 0.004 |
Total | 5.44 | |
MUFA | ||
C16:1 | g/100g | 0.41 ± 0.002 |
C18:1 n-9 | g/100g | 32.45 ± 0.76 |
C18:1 n-11 | g/100g | 0.78 ± 0.03 |
C20:1 | g/100g | 0.16 ± 0.02 |
Total | 33.80 | |
PUFA | ||
C18:2 | g/100g | 7.49 ± 0.75 |
C18:3 | g/100g | 0.18 ± 0.05 |
Total | 7.67 |
*Each value is the Mean +/− SD of the six analysed batches.
nuts like walnut or hazelnut [
The main bioactive phytochemicals content in Bronte’s pistachio is reported in
mg/100g | |
---|---|
IP6 | 1763 ± 243 |
I(1,2,4,5,6)P5 | 31 ± 16 |
I(1,2,3,4,5)P5 | 10 ± 6 |
Each value is the Mean +/− SD of the six analysed batches.
Bronte Pistachio | ||
---|---|---|
Proximate | ||
Total polyphenols | mg/100g GA | 501.5 ± 64.3 |
Carotenoids | ||
Lutein | mg/100g | 1.26 ± 0.17 |
β-carotene | mg/100g | 0.18 ± 0.05 |
Violaxanhin | mg/100g | 0.04 ± 0.01 |
Neolutein a | mg/100g | 0.02 ± 0.01 |
Neolutein b | mg/100g | 0.01 ± 0.00 |
Tocols | ||
α-tocopherol | mg/100g | 0.77 ± 0.12 |
α-tocotrienol | mg/100g | 0.13 ± 0.02 |
γ-tocopherol | mg/100g | 19.19 ± 5.31 |
γ-tocotrienol | mg/100g | 2.60 ± 0.48 |
δ-tocopherol | mg/100g | 0.43 ± 0.09 |
δ-tocotrienol | mg/100g | 0.13 ± 0.03 |
β-tocopherol | mg/100g | 0.04 ± 0.01 |
β-tocotrienol | mg/100g | 0.03 ± 0.01 |
Sterols | ||
Campesterol | mg/100g | 7.44 ± 0.16 |
Stigmasterol | mg/100g | 2.08 ± 0.33 |
β-sitosterol | mg/100g | 116.4 ± 9.14 |
Δ5-avenasterol | mg/100g | 8.52 ± 0.76 |
Total sterols | mg/100g | 134.44 ± 7.47 |
EData were the Mean +/− SD of the six analysed batches. GA, gallic acid. Carbohydrates = calculated by difference. To convert percentages of total fatty acids in % of edible portion the conversion 0.956 was applied.
mg/100g of lutein in the oil extract. The USDA database [
Tocopherols and tocotrienols (α-T, β-T, γ-T, δ-T; α-T3, β-T3, γ-T3, δ-T3) content in Bronte’s pistachio is reported in
mmol trolox/kg). Pellegrini [
Pistachios are a worth component of a healthy dietary pattern providing high protein, unsaturated fat, dietary fiber, micronutrients and a variety of bioactive compounds like sterols, tocopherols and lutein. Fat content, although high in Bronte’s pistachios (about 15 g per 30 g serving), is most of unsaturated type (41.47 g/100g, mono-plus poly-unsaturated). Among PUFA linoleic acid, an ω-6 essential fatty acid is well represented; the last Italian consumption survey [
The authors wish to thank Ulrich Schlemmer, PhD, for analysis of phytic acid and inositolpentaphospahtes. This work was supported by the Italian Ministry for Agricultural, Food and Forestry Politics (MiPAAF), Special Project BIOVITA.
LauraD’Evoli,MassimoLucarini,PaoloGabrielli,AlteroAguzzi,GinevraLombardi-Boccia, (2015) Nutritional Value of Italian Pistachios from Bronte ( Pistacia vera, L.), Their Nutrients, Bioactive Compounds and Antioxidant Activity. Food and Nutrition Sciences,06,1267-1276. doi: 10.4236/fns.2015.614132