Fatemeh Nazoori; Elaheh ZamaniBahramabadi; Hossein Rezaei
Abstract
Since processing may affect the quality and benefits of foods, a study was conducted to compare some properties of fresh, sun-dried (constant water content of 4%) and oven-roasted (130 °C for 25 min) pistachio nuts of two cultivars. Carotenoid, iron, copper, manganese, total saturated, total unsaturated, ...
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Since processing may affect the quality and benefits of foods, a study was conducted to compare some properties of fresh, sun-dried (constant water content of 4%) and oven-roasted (130 °C for 25 min) pistachio nuts of two cultivars. Carotenoid, iron, copper, manganese, total saturated, total unsaturated, palmitic, and linolenic fatty acids showed no statistical difference (P≤0.05) among the samples. Comparing the ‘Akbari’ cultivar, the ‘Ahmadaghaei’ cultivar had less anthocyanin and less palmitoleic acid. Drying and roasting reduced antioxidant activity, flavonoid content, and arachidonic acid while increasing kernel firmness, malondialdehyde, and hydrogen peroxide. Chlorophyll content was higher in dried and roasted than fresh status in both cultivars. Stearic acid had a stable content in ‘Ahmadaghaei’, but increased by drying and roasting in ‘Akbari.’ Oleic acid increased by drying and roasting in ‘Ahmadaghaei.’ In ‘Akbari,’ oleic acid first decreased by drying and then increased to the initial level by roasting. Linoleic acid decreased by drying and roasting in ‘Ahmadaghaei’. In ‘Akbari’, it revealed an increasing trend by drying, but again decreased to the initial content after roasting. In conclusion, the conditions in this experiment for drying and roasting the pistachios were not harmful and had some advantages, leading to better pistachios storage.
Fatemeh Nazoori; Elaheh ZamaniBahramabadi; Seyed Hossein Mirdehghan
Abstract
The efficiency of sulfur in controlling pistachio pests, especially psylla, has been documented in the available literature, but it is essential for pesticides not to affect the quality of the product. In this study, movento (0.5 L/1000 L), confidor (0.4 L/1000 L) and refinery micronized (R) and mineral ...
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The efficiency of sulfur in controlling pistachio pests, especially psylla, has been documented in the available literature, but it is essential for pesticides not to affect the quality of the product. In this study, movento (0.5 L/1000 L), confidor (0.4 L/1000 L) and refinery micronized (R) and mineral (M) sulfur (30 and 60 kg/1000 L in water) were sprayed twice on pistachio trees of the cultivar ‘Ahmadaghaei’ (in mid-May and 50 days thereafter). Pistachios were harvested in late September and were stored at 4 °C for 25 and 50 days to evaluate the effects of pesticides on the quality of hulls and kernels. The taste, aroma, appearance, respiration rate, firmness of hull and kernel, a* (red-green), b* (blue-yellow) and chroma of hull and kernel declined over time, while L* (lightness) and the hue angle of the hull and kernel increased. Ethylene production remained stable over time. Chemical pesticides stimulated hull firmness. Refined micronized sulfur at both concentrations caused higher L* and hue angle, but lower a*, b* and chroma in the hull and kernel (i.e. lighter and yellower in color). All sulfur treatments reduced the firmness of the hull and kernel, while also increasing the respiration rate. R30 preserved the taste and aroma after 50 days. R30 and M30 showed higher ethylene production. The R30 treatment had some positive effects on preserving the taste and aroma of pistachios overtime. Thus, it may be recommended as a reliable treatment, although the ability of sulfur in pest control could be offset by the side effects of sulfur on product quality.Abbreviations:R30: Refined micronized sulfur (30 kg/1000 L); R60: Refinery micronized sulfur (60 kg/1000 L); M30: Mineral sulfur (30 kg/1000 L); M60: Mineral sulfur (60 kg/1000 L)
Fatemeh Nazoori; Elaheh ZamaniBahramabadi; Seyed Hossein Mirdehghan; Mozhdeh Yousefi
Abstract
In recent years, sulfur has been shown to be effective in controlling pistachio psylla. In this study, the effect of sulfur foliar application as psylla pesticide on fresh fruit and kernel of three cultivars of pistachio was determined and compared with two commercial pesticides. Refinery micronized ...
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In recent years, sulfur has been shown to be effective in controlling pistachio psylla. In this study, the effect of sulfur foliar application as psylla pesticide on fresh fruit and kernel of three cultivars of pistachio was determined and compared with two commercial pesticides. Refinery micronized and mineral sulfur were applied at two concentrations of 30 and 60 kg/1000 L of water. The quality of fresh pistachio hulls and kernels were investigated. In ‘Fandoghi’ cultivar, all sulfur treatments reduced the kernel moisture. The firmness and water activity of hulls and kernels were significantly affected. All sulfur treatments decreased hull lightness in ‘Fandoghi’, while it increased in ‘Akbari’ and ‘Ahmadaghaei’ cultivars. Reduction of hull chroma was observed in some cases in all cultivars. Hue of hulls was not affected by the treatments. Lightness, chroma and hue values of the testa of kernels were not affected in ‘Fandoghi’ and ‘Akbari’. In ‘Ahmadaghaei’, refinery micronized sulfur increased the testa lightness and hue and decreased chroma probably because of the softer texture of hull in ‘Ahmadaghaei’ which breaks more easily during harvest practice. Sulfur treatments positively influenced appearance and general acceptance of ‘Ahmadaghaei’ fruits. The taste and aroma of pistachios were preserved in most of treatments. High concentration (60 kg/1000 L) of both sulfur types enhanced the ethylene production in ‘Ahmadaghaei’ which was almost same as the unripe fruit because sulfur treatments reduced the percentage of unripe fruit. In ‘Ahmadaghaei’, refinery micronized sulfur treatments increased the respiration rate.
Fatemeh Nazoori; Solmaz Poraziz; Seyed Hossein Mirdehghan; Majid Esmailizadeh; Elaheh ZamaniBahramabadi
Abstract
In the present study, effects of edible coatings using sodium alginate (SA) and sodium alginate in combination with ascorbic acid (AA) on the shelf-life extension of strawberries at 4±1°C was studied. A factorial experiment was performed based on a randomized complete block design with four ...
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In the present study, effects of edible coatings using sodium alginate (SA) and sodium alginate in combination with ascorbic acid (AA) on the shelf-life extension of strawberries at 4±1°C was studied. A factorial experiment was performed based on a randomized complete block design with four replications. The treatments included control (distilled water), SA (1%, 2%, 3% w/v), SA in combination with AA (1% w/v) and the storage periods (7 and 14 days). The results showed that lightness (L*), chroma, firmness, total acidity, vitamin C, phenols, and antioxidant activity decreased during storage, but coating improved them in the sold-stored strwberries. SA2%+AA1% coating was the best treatment in maintaining the fruit quality. Firmness, weight loss, fruit L*, fruit chroma, sepal L*, sepal chroma, total phenolics, and polyphenol oxidase activity were decreased by 15%, 1.95%, 16.7%, 2.66%, 10.23%, 16%, 19.47% and 2.5%, respectively for SA2%+AA1% samples at the end of the 14th day, which was lower than the untreated fruits. The results suggested that postharvest application of SA2%+AA1% has the potential to extend the storage life of strawberry fruits by reducing water loss and maintaining fruit quality.
