Influence of Ripeness and Drying Process on the Polyphenols and Tocopherols of Pistacia vera L.

Abstract

This paper highlights, for the first time, the changes in the phenolics fraction (anthocyanins, flavonoids and stilbenes) and tocopherols of unpeeled Pistacia vera L. var. bianca with ripening, and the effect of the sun-drying process. The total polyphenol levels in pistachios, measured as mg of Gallic Acid Equivalent (GAE), were: 201 ± 10.1, 349 ± 18.3 and 184.7 ± 6.2 mg GAE/100 g DM in unripe, ripe and dried ripe samples, respectively. Most phenolics in ripe pistachios were found to be anthocyanins. They increased with ripening, while the sun drying process caused a susbtantial loss. Flavonoids found in all pistachio samples were daidzein, genistein, daidzin, quercetin, eriodictyol, luteolin, genistin and naringenin, which decreased both with ripening and drying. Before the drying process both unripe and ripe pistachios showed a higher content of trans-resveratrol than dried ripe samples. γ-Tocopherol was the major vitamin E isomer found in pistachios. The total content (of α- and γ-tocopherols) decreased, both during ripening and during the drying process. These results suggested that unpeeled pistachios can be considered an important source of phenolics, particularly of anthocyanins. Moreover, in order to preserve these healthy characteristics, new and more efficient drying processes should be adopted.

Tree nut phytochemicals: composition, antioxidant capacity, bioactivity, impact factors. A systematic review of almonds, Brazils, cashews, hazelnuts, macadamias, pecans, pine nuts, pistachios and walnuts

“…Monagas et al (15) reported the catechin content and Del Rio et al (38) reported monomeric and oligomeric flavan-3-ols, flavonols, dihydrochalcones and phenolic acids in hazelnut skins. Although these studies did not report polyphenol content in terms of whole hazelnuts, monomeric and oligomeric (5) 2052 (28,80,86,92) 2713·49 (10 -12,18,28) 493·90 (1) 233·52 (70,169,170,175) ND Pine nuts 206 26 (5) ND 0·03 (11,12) 1 (11,13,18,43) § 190·75 (70,169,170,175,189,190) ND Pistachios 703 22 832 (5,50,87) 1·27 (191) 136·45 (10 -12,18,40,42,43,191) 252·71 (1) 189·43 (70,88,169 -171,175,192) 803·22 (40,43,48,49) Walnuts 1602 21 (5) 39·11 (44,51,60,193,194) 0·54 (11,12,…”

“…, Grippi et al (49) and Ballistreri et al (40) have reported on the stilbene content of pistachios but these data have yet to be submitted or included in the PE database. Other tree nuts may contain stilbenes, but a systematic analysis of their abundance is lacking.…”

Effect of postharvest storage temperatures on the quality parameters of pistachio nuts

“…However, the low production is compensated for by the very high quality (Bellomo & Fallico 2007). The Italian pistachio, which comes from Bronte (Southern Italy) and represents approximately 80% of the Italian production with just one variety (Bianca), shows, at ripeness, a red-violet skin while retaining a green nutmeat (Ballistreri et al 2009). Usually, it is picked fully ripe and sold as a green product.…”

Antepfıstığı (Pistacia vera L.) ve İnsan Sağlığı Üzerine Etkileri

“…Ballistreri ve ark. [43], E vitamini bakımından antepfıstığında en fazla ɣ-tokoferol tespit etmişlerdir. Ayrıca olgunluk ve kurutma aşaması sırasında toplam ɣ ile α tokoferollerin azaldığını ve ɣ-tokoferolün antioksidan aktivitesinin α-tokoferole göre daha yüksek olduğunu bildirmişlerdir.…”