Pressurised water extraction of polyphenols from pomegranate peels

Pomegranate peels are one of the most valuable by-products of the food industry in terms of polyphenols which are conventionally extracted from plant materials by organic solvents, especially with methanol. Pressurised water extraction was investigated for the extraction of polyphenols from pomegranate peels. The most important factors affecting the extraction results were found to be particle size, temperature, and static time. The results indicated that pressurised water extraction was as effective as conventional methanol extraction for the recovery of polyphenols from pomegranate peels. Total phenolic contents of pomegranate peels obtained by pressurised water extraction at optimised conditions and conventional solid–liquid methanol extraction were determined as 264.3 and 258.2 mg/g tannic acid equivalents, respectively. Hydrolyzable tannins were the predominant polyphenols of pomegranate peels corresponding to 262.7 mg/g tannic acid equivalents. Punicalagin content of pomegranate peels by pressurised water extraction was found to be 116.6 mg/g on dry matter basis.     

Effects of UV-C Light Processing on Some Quality Characteristics of Grape Juices

White and red grape juices (GJs) were subjected to ultraviolet C (UV-C) light as a non-thermal preservation technology using a coiled tube UV-C reactor with nine lamps. The effects of UV-C light on microbial (total aerobic count and yeast and mould count) and some chemical quality characteristics (total phenolics, antioxidant capacity, anthocyanin and polymeric colour, etc.) of white and red GJs were investigated. The results were compared with control (untreated) and heat-treated juice samples. Single-pass UV-C treatment (12.6 J/mL) of white and red GJs resulted in 3.51 and 3.59 log reductions in total aerobic count and, 2.71 and 2.89 log reductions in yeast and mould counts, respectively. The microbial loads of both GJs were completely eliminated after two passes through the reactor (25.2 J/mL). After UV-C and heat treatments, there were no significant changes in antioxidant capacity, total phenolics, titratable acidity, soluble solids and pH of white and red GJs (P?>?0.05). The losses in monomeric anthocyanins were 6.1% and 8.7% after UV-C treatment of 12.6 and 25.2 J/mL doses, respectively. However, anthocyanin level of red GJ was significantly affected by the heat treatment with an 11.8% loss (P?<?0.05). The percent polymeric colour of the red GJ with heat treatment was significantly higher compared to the colour with the UV-C treatment.     

Comparison of total antioxidant capacity and phenolic composition of some apple juices with combined HPLC–CUPRAC assay

It was aimed in this study to identify and quantify various constituents (particularly phenolics) of apple juice and to quantitatively compare the total antioxidant capacities of juices obtained from apple varieties grown in Turkey.     

Adaptive control of let-off system in weaving

In this study, semi-positive let-off system in a conventional weaving loom was controlled using conventional, PID (Proportional Integral Derivative) and fuzzy logic based control systems. To do this, servomotor was installed into the let-off unit of the loom using PID controller, additionally fuzzy logic based let-off control was realised. Experimentally obtained warp tension values for each control methods were compared. According to the results, maximal tension values for the conventional, PID and fuzzy logic controlled systems were found to be 53, 45 and 35 cN, respectively. As a result, it is determined that the least warp tension interval and mean warp tension value are in let-off system controlled by fuzzy logic.     

HPLC-DAD Analysis to Identify the Phenolic Profile of Rhododendron Honeys Collected from Different Regions in Turkey

In this study, phenolic compounds of Rhododendron honey (also known as mad honey) samples collected from the Black Sea Region were identified using high performance liquid chromatography-diode array detector system. The major phenolic substances in Rhododendron honeys were found to be chlorogenic and coumaric acids with the amounts of 0.11–191.54 mg/kg and 0–82.83 mg/kg, respectively. Gallic and ferulic acids were detected in the most honey samples. Additionally, significant correlations were determined between the phenolic substances. The present study showed that Rhododendron honeys contained higher quantities of phenolic acids than flavonoids. Chlorogenic and coumaric acids were the dominant phenolic substances detected in honey samples.     

Moisture Dependent Physical Properties of Dry Sweet Corn Kernels

Physical properties of sweet corn kernels have been evaluated as a function of kernel moisture content, varying from 9.12 to 17.06% (db). In the moisture range, kernel length, width, thickness, and geometric mean diameter increased linearly from 9.87 to11.09 mm, 7.41 to 9.25 mm, 3.25 to 4.37 mm, and 6.18 to 7.62 mm, respectively, with increase in moisture content from 9.12–17.06%. The sphericity index, kernel volume, kernel surface area, and thousand seed weight increased linearly from 62.6 to 68.8, 93.8 to 194.3 mm³, 120.1 to 182.9 mm², and 220 to 268 gr, respectively. Apparent density and bulk density decreased linearly from 1.315 to 1.232 g/cm³ and 0.765 to 0.698 g/cm³, respectively, while bulk porosity increased from 41.8 to 43.3%. The highest static coefficient of friction was found on the plywood surface. The static coefficient of friction increased from 0.680 to 0.891, 0.605 to 0.741, and 0.530 to 0.644 for plywood, galvanized iron, and aluminum surfaces, respectively. The angle of repose increased linearly from 30.2 to 35.2° with the increase of moisture content.     

Effects of structural parameters on compressibility and soiling properties of machine woven carpets

Compressibility performance of the machine woven carpet after a static or dynamic loading expresses the texture deformation tendency of the carpet. This study is an experimental attempt to investigate the effects of pile height and pile density on compressibility and soiling property by dynamic loading, prolonged heavy static loading, compression recovery and artificial soiling tests. In this study, a total of 12 carpet samples with three different pile heights and four different pile densities were tested. As a result of this study, it was seen that higher pile density provides a lower thickness loss and so a lower level of texture deformation. On the other hand, pile height has a preventing effect for texture deformation for static loading and compression recovery tests whereas there is no considerable effect on dynamic loading test. There is no considerable difference between the soiling properties of the samples.