Quality stability of clear pomegranate juice treated with cyclodextrin.

Protective effect of cyclodextrin (CD) on some quality characteristics of clear pomegranate juice (CPJ) was investigated. CPJ with no CD addition (Control) and CPJ samples, subjected to different type (ß-CD and Hydroxy propyl (HP-ß-CD) and concentration (0.5, 1% and 2%) combinations of CD, were stored at 25 °C for 3 months. The changes in color characteristics (polymeric color and total color difference - ΔE), total phenolic content (TPC) and antioxidant activity (AA) of all PJ samples monitored at 1 month intervals. Although overall color change of the PJ samples was hardly perceived visually, none of the treatments were successful to protect the initial color of clear PJ technically (P > 0.05). Among the CD treatments, HP-ß-CD with a concentration of 0.5% was found effective to prevent TPC and AA losses of PJ (P < 0.05). On the other hand, ß-CD addition did not cause any improvement in protecting color, TPC and AA of clear PJ during storage, compared to control juice.

Ultrasound-assisted dilute acid hydrolysis of tea processing waste for production of fermentable sugar.

Lignocellulosic materials that are the most abundant plant biomass in the world have the potential to become sustainable sources of the produced value added products. Tea processing waste (TPW) is a good lignocellulosic source to produce the value added products from fermentable sugars (FSs). Therefore, the present study is undertaken to produce FSs by using ultrasound-assisted dilute acid (UADA) and dilute acid (DA) hydrolysis of TPW followed by enzymatic hydrolysis. UADA hydrolysis of TPW was optimized by response surface methodology (RSM) at maximum power (900 W) for 2 h. The optimum conditions were determined as 50°C, 1:6 (w/v) solid:liquid ratio, and 1% (w/v) DA concentration, which yielded 20.34 g/L FS concentration. Furthermore, its DA hydrolysis was also optimized by using RSM for comparison and the optimized conditions were found as 120°C, 1:8 solid:liquid ratio, and 1% acid concentration, which produced 25.3 g/L FS yield. Even though the produced sugars with UADA hydrolysis are slightly less, but it can provide significant cost saving due to the lower temperature requirement and less liquid consumption. Besides, enzymatic hydrolysis applied after pretreatments of TPW were very more economic than the conventional enzymatic hydrolysis in the literature due to shorter time requiring. In conclusion, ultrasound-assisted is a promising technology that can be successfully applied for hydrolysis of biomass and can be an alternative to the other hydrolysis procedures and also TPW can be considered as suitable carbon source for the production of value-added products like biofuels, organic acids, and polysaccharides. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:393-403, 2016.

Determination of D-pinitol in carob syrup.

Carob syrup is a traditional product native to the Mediterranean region, containing a high concentration of sugar, phenolic compounds and minerals. d-pinitol is a bioactive component extracted from legumes and has some beneficial effects on human metabolism. In this research, the d-pinitol content and sugar profile of 10 different carob syrup samples purchased from Turkish markets were determined. Mean d-pinitol, sucrose, glucose and fructose contents of samples were found to be 84.63 ± 10.73, 385.90 ± 45.07, 152.44 ± 21.72 and 162.03 ± 21.45 g/kg dry weight, respectively. Carob syrup has a considerable amount of d-pinitol compared with the other d-pinitol-including legumes. Consequently, this study showed that carob syrup may be a suitable source of d-pinitol for medical use and d-pinitol may be an indicator for the detection of any adulteration in carob syrup.

Ethanol production from carob extract by using Saccharomyces cerevisiae.

Carob has been widely grown in the Mediterranean region for a long time. It has been regarded as only a forest tree and has been neglected for other economical benefits. However, in recent years, this fruit has gained attention for several applications. As petroleum has become depleted, renewable energy production has started to gain attention all over the world; including the production of ethanol from underutilized agricultural products such as carob. In this project, the optimum extraction conditions were determined for the carob fruit by using the response surface design method. The obtained extract was utilized for production of ethanol by using suspended Saccharomyces cerevisiae fermentation. The effect of various fermentation parameters such as pH, media content and inoculum size were evaluated for ethanol fermentation in carob extract. Also, in order to determine economically appropriate nitrogen sources, four different nitrogen sources were evaluated. The optimum extraction condition for carob extract was determined to be 80 degrees C, 2h in 1:4 dilution rate (fruit: water ratio) according to the result of response surface analysis (115.3g/L). When the fermentation with pH at 5.5 was applied, the final ethanol concentration and production rates were 42.6g/L and 3.37 g/L/h, respectively, which were higher than using an uncontrolled pH. Among inoculum sizes of 1%, 3%, and 5%, 3% was determined as the best inoculum size. The maximum production rate and final ethanol concentration were 3.48 g/L/h and 44.51%, respectively, with an alternative nitrogen source of meat-bone meal. Overall, this study suggested that carob extract can be utilized for production of ethanol in order to meet the demands of renewable energy.