Necati Barış Tuncel

Infrared stabilization of rice bran and its effects on γ‐oryzanol content, tocopherols and fatty acid composition

BACKGROUND Rice bran is a nutritionally valuable by-product of paddy milling. In this study an experimental infrared (IR) stabilization system was developed to prevent rice bran rancidity. The free fatty acid content of raw and IR-stabilized rice bran samples was monitored every 15 days during 6 months of storage. In addition, energy consumption was determined. RESULTS The free fatty acid content of rice bran stabilized at 600 W IR power for 5 min remained below 5% for 165 days. No significant change in γ-oryzanol content or fatty acid composition but a significant decrease in tocopherol content was observed in stabilized rice bran compared with raw bran. IR stabilization was found to be comparable to extrusion with regard to energy consumption. CONCLUSION IR stabilization was effective in preventing hydrolytic rancidity of rice bran. By optimizing the operational parameters of IR stabilization, this by-product has the potential for use in the food industry in various ways as a value-added commodity.

Time and temperature dependent microbiological and mycotoxin (ochratoxin-A) levels in boza

This study describes the examination of microbiological tests and the determination of OTA in boza temperature and time dependently. Prior to the analysis, physicochemical properties of the boza samples such as moisture, total acidity as lactic acid, pH, protein amount and viscosity were investigated. The incidence of total aerobic bacteria (TAB), lactic acid bacteria (LAB), coliforms, E.coli, Salmonella, S. aureus, B. cereus, yeast and moulds were examined. E.coli, Salmonella, S. aureus and B. cereus were not found in all boza samples. Initially, Aspergillus fumigatus; Acremonium sp.; Geotrichum candidum and Geotrichum capitatum were identified in the samples. Certain extraction techniques such as direct injection, liquid-liquid and solid phase (SP) were tried for the OTA analysis. The most available way was found to be direct injection among them and the recovery was 70.56%+/-9.80 (13.89 RSD). OTA amounts were determined in all boza samples utilizing an isocratic HPLC analysis with an ODS column. OTA was detected in only one sample as 3.58 microg/kg and this amount is above the limits of European Commission Regulations. Time and temperature-dependent changes were investigated and insignificant variation was observed.

Effect of black mulberry (Morus nigra) extract treatment on cognitive impairment and oxidative stress status of d-galactose-induced aging mice

Abstract Context: Morus nigra L. (Moraceae) has various uses in traditional medicine. However, the effect of M. nigra on cognitive impairment has not been investigated yet. Objective: The objective of this study is to determine the phenolic acid content and DNA damage protection potential of M. nigra leaf extract and to investigate the extract effect on cognitive impairment and oxidative stress in aging mice. Materials and methods: Phenolic acid content was determined by quantitative chromatographic analysis. DNA damage protection potential was evaluated on pBR322 plasmid DNA. Thirty-two Balb-C mice were randomly divided into four groups (control, d-galactose, d-galactose + M. nigra 50, and d-galactose + M. nigra 100). Mice were administered d-galactose (100 mg/kg, subcutaneous) and M. nigra (50 or 100 mg/kg, orally) daily for 8 weeks. Behavioral responses were evaluated with Morris water maze. Activities of antioxidant enzymes and levels of malondialdehyde (MDA) were assayed in serum, brain, and liver. Results: In extract, vanillic (632.093 μg/g) and chlorogenic acids (555.0 μg/g) were determined. The extract between 0.02 and 0.05 mg/mL effectively protected all DNA bands against the hazardous effect of UV and H2O2. Morus nigra significantly improved learning dysfunctions (p < 0.01), increased memory retention (p < 0.01), reduced MDA levels (p < 0.05), and elevated SOD, GPx, and CAT activities (p < 0.05) compared with the d-galactose group. Discussion and conclusion: These results show that M. nigra has the potential in improving cognitive deficits in mice and that M. nigra may be useful to suppress aging, partially due to its scavenging activity of free radicals and high antioxidant capacity.

Utilization of lentil, pea, and faba bean hulls in Turkish noodle production

Turkish noodles (erişte) were substituted with green lentil (Lens culinaris), red lentil (L. culinaris), faba bean (Vicia faba), and pea (Pisum sativum) hulls at the level of 2.5, 5, and 10% and the effects of the substitution on proximate composition, mineral composition, colour, cooking properties, thiamine and riboflavin contents, texture and sensory properties of the noodles were investigated. Crude ash, dietary fibre, Ca and Mg contents of the noodles significantly increased with pulse hull substitution regardless of the hull type compared to control. Lightness or brightness (L*) values of the noodles showed a general decreasing trend with increasing pulse hull substitution excluding pea hull. L* value of the pea hull substituted noodles was higher than that of the control. Water absorption and swelling volume of the noodles remarkably increased with pea hull substitution. Thiamine and riboflavin contents of the control noodles and the noodles substituted with the noted hull types up to 10% were very close to each other. Noodles substituted with faba bean hull at the level of 10% showed the highest hardness, gumminess, and chewiness values. Pea hull substitution up to 10% did not significantly affected the sensory (appearance, texture and overall acceptability) scores of the panellists.

Pirinç ve Pirinç Yan Ürünlerinin Glutensiz Tahıl Ürünlerinde Kullanımı

Dunya uzerinde her toplumun beslenme aliskanligi farklilik gostermesine ragmen tahil urunleri tum bu beslenme tiplerinin en temel kaynagini olusturmaktadir. Tahil urunleri insanlar icin onemli bir besin kaynagi olmakla beraber bazi hastaliklarin olusumunda da kritik bir rol oynamaktadir. Gluten proteini iceren tahillarin tuketilmesiyle sindirim sisteminde bu proteinden kaynaklanan reaksiyonlar meydana gelmekte ve bagirsakta emilimin zorlasmasina bagli olarak gida intoleranslari olusmaktadir. Bu gida intoleranslarindan biri de colyak hastaligidir. Colyak hastaligi, yapisinda gluten bulunan gidalarin tuketilmesiyle ortaya cikan bir emilim bozuklugudur. Hastaliga neden olan temel faktor gluten proteininin gliadin alt fraksiyonudur. Basta bugday olmak uzere gliadin homologu prolaminleri iceren arpa, cavdar ve tritikale gibi urunlerin tuketilmesi colyak hastaligina neden olmaktadir. Hasta olan kisilerde bagirsaklardaki villuslarin deforme olmasi nedeniyle vucudun ihtiyaci olan vitamin ve minerallerin emilimi de zorlasmaktadir. Colyak hastaliginin tek tedavi yolu hayat boyu glutensiz bir diyet uygulanmasidir. Bu nedenle colyak hastalarinin diyetleri icin ekmek basta olmak uzere biskuvi, makarna, cerez tipi urunler gibi bircok firincilik urunu gelistirilmektedir. Hastalik icin uretilen firincilik urunlerinde gluten proteininin eksikligi nedeniyle istenen tat ve gorunusu saglamak zorlasmaktadir. Glutensiz firin urunlerinin kabul edilebilir bir kalitede olmasini saglamak amaciyla gluten iceren bugday unu yerine yapisinda gluten proteinini bulundurmayan pirinc unu, pirinc kepegi, kahverengi pirinc unu kullanilmaktadir. Son yillarda gluten icermeyen gidalarda pirinc ve pirinc yan urunlerinin kullanimi, cesitli un karisimlari, nisastalar (misir nisastasi, pirinc nisastasi, patates nisastasi) ve hidrokolloidlerin (guar gam, ksantan gam, hidroksi propil metil seluloz) kombinasyonlari ile hazirlanan formulasyonlarin kullanimi uzerine arastirmalar yapilmaktadir. Bu derlemede colyak hastaligi, pirinc ve pirinc yan urunlerinin fonksiyonel ozellikleri ve glutensiz urunlerde kullanimi uzerine yapilan arastirmalar uzerinde durulmustur.

Quality properties, mass transfer characteristics and energy consumption during shortwave infrared radiation drying of tomato

The influence of infrared radiation intensity (1,830, 2,640 and 3,165 W/m2) and air velocity (1.0, 1.5 and 2.0 m/s) on product quality, drying behaviour of tomato and energy consumption were investigated. Five analytical models were used to investigate mass transfer characteristics during infrared drying of tomato slices. The drying time and specific energy consumption varied between 141 and 246 min, and 10.04 and 15.13 MJ/kg water, respectively, and were significantly influenced by infrared radiation intensity and air velocity. Effective moisture diffusivity ranged from 3.89×10-7 to 6.67×10-7 m2/s and was significantly affected by the process variables. Vitamin C content decreased, while lycopene content increased during drying. Total colour change varied between 7.92 and 10.87 for all drying conditions. The logarithmic model gave the best predictions for the drying characteristics of tomato slices for all treatments. Some drying conditions had quite similar results with respect to the operational and qu...