Influence of extraction solvents on the polyphenol contents, compositions, and antioxidant capacities of fig (Ficus carica L.) seeds.

Fig seeds are considered to be significantly responsible for the bioactive compounds of fig. In this study, the effects of six different solvents (100% acetone, 100% methanol, 100% ethanol, 50% (v/v) aqueous acetone, 50% (v/v) aqueous methanol and 50% (v/v) aqueous ethanol) with changing polarities on the polyphenol contents and antioxidant capacities of fig seed extracts were investigated. Total polyphenol contents (TPCs), total flavonoid contents (TFCs), antioxidant capacities (DPPH and FRAP assays) and polyphenol compositions of the extracts were evaluated. The results indicated that fig seeds extracted by 50% (v/v) aqueous methanol exhibited the highest TPC (714 mg GAE/kg DM), TFC (312 mg (+)-CE/kg DM), DPPH (41.6%) and FRAP (8504 mg FeSO4/kg DM) values. Also, same extract had the maximum values of chlorogenic acid (131.9 mg/kg DM), (-)-epicatechin (166.4 mg/kg DM) and rutin (50.7 mg/kg DM) (p<0.05). The extractability of syringic acid was determined to be highest with 50% aqueous methanol (8.03 mg/kg DM) and 50% aqueous ethanol (8.13 mg/kg DM) (p>0.05). The psoralen extractability was highest in 50% aqueous acetone (53.0 mg/kg DM) and 50% aqueous ethanol (54.0 mg/kg DM) (p>0.05). High correlations among TPCs, TFCs, antioxidant capacities and individual polyphenols of fig seed extracts were also observed.

Kinetics of colour and texture changes of button mushrooms (Agaricus bisporus) coated with chitosan during storage at low temperature.

Kinetics of color and texture changes in coated button mushrooms were investigated as a function of coating agent's rate (1%, 2% and 3% w/v chitosan). The inner and outer surface colours of mushrooms in terms of CIELAB parameters L*, a*, b*, C*, ° h, ∆E, and Browning Index (BI), and their textural properties in terms of firmness were evaluated. The color values on both sides of the mushrooms except for L* values increased and their firmness decreased with the coating treatment. The color changes of the inner and outer surface of mushrooms and their texture changes followed zero-order reaction models with higher R2 (0.9987-0.9999) and lower RMSE (4.8448 x 10-5-1.6690) and χ2 values (3.9120 x 10-9-4.6425). The 2% chitosan solution was determined to be the most effective coating agent among the coating agents used to extend the post-harvest shelf life by optimally preserving the color parameters of the mushrooms together with their texture properties.

Kinetic modelling of vitamin C losses in fresh citrus juices under different storage conditions.

The degradation kinetics of vitamin C in different citrus juice types (tangerine, grapefruit, orange and lime) were investigated during four hours storage at temperatures of 4 and 25°C under different storage conditions in terms of light and oxygen presence. The loss of vitamin C at each sample followed the first-order kinetic model. During storage, predicted half-life of vitamin C ranged from 137.586 to 467.486 min for tangerine; 105.444 to 203.100 min for grapefruit; 365.702 to 1044.668 min for orange and 540.076 to 722.016 min for lime juices. These results indicated that the highest and lowest retentions of vitamin C were observed in orange and grapefruit juices respectively during storage. Additionally, storage time, light penetration and oxygen presence were the most effective factors on vitamin C degradation while the storage temperature revealed no significant effect on the vitamin C content.

Physical characterization of Arabica ground coffee with different roasting degrees.

Roasting is a determinative operation on the final quality of coffee. Roasting process causes physical, chemical and sensory changes on coffee. In this study roasting degree effect on physical properties of Arabica fine ground coffee was examined. The bulk properties, particle property, reconstitution properties, moisture content, water activities and color properties were investigated in different roasting degrees of coffee. The results showed that the physical characteristics of coffee samples were influenced by the degree of roast. To have longer shelf life, lower cost and better physical attributes of Arabica fine ground coffee, the roasting process should be kept at a lower degree. At the same time the requests and expectations of customer should also be considered.