A novel antioxidant source: evaluation of in vitro bioaccessibility,antioxidant activity and polyphenol profile of phenolic extract from black radish peel wastes (Raphanus sativus L. var. niger) during simulated gastrointestinal digestion

The aim of this study was to evaluate the potency of polyphenolic extract from black radish (Raphanus sativus L. var. niger) root peel waste (PEBRRP) as an antioxidant food additive. PEBRRP was found a powerful antioxidant extract, in which had 172.9 ± 11.5, 462.72 ± 3.05, and 796.51 ± 10.4 mg TE per g dw of total antioxidant capacity (TAC) by CUPRAC, DPPH, and FRAP assays, respectively. The total phenolic content (TPC) and total flavonoid content (TFC) of PEBRRP were found as 305.51 ± 5.2 mg GAE per g dw and 171.58 ± 6.2 mg CAE per g dw, respectively. The ferulic acid (28.02 ± 4.5 mg per g dw) and epicatechin (19.82 ± 3.6 mg per g dw) were identified as the main polyphenols in undigested PEBRRP. The bioaccessibility of total phenolic and total flavonoid compounds of PEBRRP was found approximately 5%, and the antioxidant capacity of bioaccessible PEBRPP fraction was determined 6% in CUPRAC, 36% in DPPH and 47% in FRAP methods.     

Maintenance of safety and quality of refrigerated ready-to-cook seasoned ground beef product (meatball) by combining gamma irradiation with modified atmosphere packaging

Abstract: Meatballs were prepared by mixing ground beef and spices and inoculated with E. coli O157:H7, L. monocytogenes, and S. enteritidis before packaged in modified atmosphere (3% O₂+ 50% CO₂+ 47% N₂) or aerobic conditions. The packaged samples were irradiated at 0.75, 1.5, and 3 kGy doses and stored at 4 °C for 21 d. Survival of the pathogens, total plate count, lipid oxidation, color change, and sensory quality were analyzed during storage. Irradiation at 3 kGy inactivated all the inoculated (approximately 10⁶ CFU/g) S. enteritidis and L. monocytogenes cells in the samples. The inoculated (approximately 10⁶ CFU/g) E. coli O157:H7 cells were totally inactivated by 1.5 kGy irradiation. D¹⁰‐values for E. coli O157:H7, S. enteritidis, and L. monocytogenes were 0.24, 0.43, and 0.41 kGy in MAP and 0.22, 0.39, and 0.39 kGy in aerobic packages, respectively. Irradiation at 1.5 and 3 kGy resulted in 0.13 and 0.36 mg MDA/kg increase in 2‐thiobarbituric acid‐reactive substances (TBARS) reaching 1.02 and 1.49 MDA/kg, respectively, on day 1. Irradiation also caused significant loss of color and sensory quality in aerobic packages. However, MAP effectively inhibited the irradiation‐induced quality degradations during 21‐d storage. Thus, combining irradiation (3 kGy) and MAP (3% O₂+ 50% CO₂+ 47% N₂) controlled the safety risk due to the potential pathogens and maintained qualities of meatballs during 21‐d refrigerated storage. Practical Application: Combined use of gamma irradiation and modified atmosphere packaging (MAP) can maintain quality and safety of seasoned ground beef (meatball). Seasoned ground beef can be irradiated at 3 kGy and packaged in MAP with 3% O₂+ 50% CO₂+ 47% N₂ gas mixture in a high barrier packaging materials. These treatments can significantly decrease risk due to potential pathogens including E. coli O157:H7, L. monocytogenes, and S. enteritidis in the product. The MAP would reduce the undesirable effects of irradiation on quality, and extend the shelf life of the product for up to 21 d at 3 °C.     

Biochemical Characterization of Arbequina Extra Virgin Olive Oil Produced in Turkey

Varieties of the olive cultivar Arbequina have recently been cultivated in Turkey. The objective of the study is to characterize and evaluate extra‐virgin olive oils (EVOO) produced from Arbequina grown in the Aegean and Mediterranean regions of Turkey. Major and minor components such as carotenoids, squalene, phenolics and tocopherols were studied to assess their effects on product quality and health benefits. The samples, identified as ArbqI and ArbqA, were from the Izmir and Adana provinces, respectively. Samples were analyzed by GC‐FID to determine fatty acid composition, sterol composition, TAG profile and squalene content. Individual phenolic fractions were analyzed by LC–MS/MS and tocopherol isomers were determined by HPLC. According to the results obtained from this study; Total phenolic content (TPC) of the samples were 454.68 and 50.86 mg Gallic acid/kg oil for ArbqI and ArbqA, respectively. Hydroxytyrosol and tyrosol were determined to be the main phenols. The major tocopherol isomer found in ArbqI and ArbqA was α‐tocopherol with levels of 179.55 and 202.5 mg/kg oil, respectively. β‐Carotene levels in both samples were similar at 0.2 mg/kg. Findings of this study were compared with the literature on Arbequina olive oil produced in different countries. It was determined that Arbequina olive oil of high quality can be produced in Turkey, especially in the Aegean region.     

Use of Bacillus indicus HU36 as a probiotic culture in set‐type,recombined nonfat yoghurt production and its effects on quality

Viability of a probiotic and carotenoid‐producing bacterium, Bacillus indicus HU36 in vegetative form, along with the yoghurt cultures in set‐type, recombined nonfat yoghurt and its effects on quality were determined during the storage at 4 °C. The number of B. indicus HU36 cells in yoghurt remained about 5 log cfu/mL after 14 days, but decreased to 3.5 log after 21 days. The bacterium resulted in increased yellowness, but did not affect the rheological properties of the yoghurt. Sensorial properties of the yoghurt were acceptable compared to a commercial probiotic yoghurt. B. indicus HU36 can thus be used as a probiotic culture in yoghurt production.     

Antioxidant activity and total phenolic,organic acid and sugar content in commercial pomegranate juices

Pomegranate fruit and pomegranate juices (PJs) have taken great attention for their health benefits in the last years. The purpose of this study is to analyse the antioxidant activities, along with the organic acid and sugar contents of pomegranate juices sold in the Turkish markets. In the present study, we evaluated total phenolics (TPs), free radical scavenging capacity by 2,2-diphenyl-1-picrylhydrazyl (DPPH), and ferric reducing capacity of seven commercial PJs. Organic acid and sugar contents of juices were determined by capillary zone electrophoresis. The results showed that commercial pomegranate juices had markedly high total phenolic contents and antioxidant capacity. Fructose (F) and glucose (G) were found as the major sugars. The major acids were citric and malic. From the F/G ratio, organic acid profiles, TPs, and antioxidant capacity values, a possible adulteration was detected in one of the juices.     

Review of Methods to Determine Antioxidant Capacities

Antioxidant capacity is related with compounds capable of protecting a biological system against the potentially harmful effect of processes or reactions involving reactive oxygen and nitrogen species (ROS and RNS). These protective effects of antioxidants have received increasing attention within biological, medical, nutritional, and agrochemical fields and resulted in the requirement of simple, convenient, and reliable antioxidant capacity determination methods. Many methods which differ from each other in terms of reaction mechanisms, oxidant and target/probe species, reaction conditions, and expression of results have been developed and tested in the literature. In this review, the methods most widely used for the determination of antioxidant capacity are evaluated, presenting the general principals, recent applications, and their strengths and limitations. Analysis conditions, substrate, and antioxidant concentration should simulate real food or biological systems as much as possible when selecting the antioxidant capacity method. The total antioxidant capacity value should include methods applicable to both lipophilic and hydrophilic antioxidants, with regards the similarity and differences of both hydrogen atom transfer and electron transfer mechanism. The methods including various ROS/RNS also have to be designed to comprehensively evaluate the antioxidant capacity of a sample.     

Production of human milk fat substitute with medium-chain fatty acids by lipase-catalyzed acidolysis: Optimization by response surface methodology

The aim of this study was to synthesize human milk fat substitute (HMFS) enriched with medium-chain fatty acids (MCFAs) by Lipozyme^® RM IM-catalyzed acidolysis. The reaction substrates (tripalmitin, hazelnut oil fatty acids and Neobee^® fatty acids) were specially chosen to mimic human milk fats and to enrich HMFS with MCFAs. Substrate molar ratio, reaction temperature and enzyme content were used to model and to optimize the reaction conditions via response surface methodology. The experiment was carried out at the optimal condition generated from the model yielded structured lipids with caprylic acid (12.8 g/100 g), capric acid (10.6 g/100 g) and palmitic acid (30 g/100 g). These values were found similar to the values predicted by the model (15.9 g/100 g, 14.1 g/100 g and 33.3 g/100 g). It can be concluded that the potential use of the structured lipids (SLs) produced in infant formulas provide energy source delivering a reduced calorie value for newborn, term and preterm infants.     

Optimisation of enzymatic synthesis of diacylglycerols in binary medium systems containing ionic liquids

Two different approaches, namely the n-hexane/ionic liquid (IL) system and the binary IL system, were optimised as a reaction medium for selective production of diacylglycerols (DGs) by lipase-catalysed glycerolysis of triolein. ILs used are [BMIM]·[BF₄], [BMIM].[PF₆], [OMIM]·[PF₆], [TOMA]·[TFA], [TOMA]·[Tf₂N], and Ammoeng 120. The effect of mixing n-hexane with IL in different ratios and at different temperatures was found to depend on the polarity of the IL used. In general, the addition of n-hexane resulted in improvement of triacylglycerol (TG) conversion and DG yield. The enhancement of mass transfer due to the decrease of viscosity is a major reason. The binary IL systems were evaluated with the aim of increasing DG yield and TG conversion while decreasing monoacylglycerol (MG) content. The reaction conditions of glycerolysis in the binary IL system consisting of [TOMA]·[Tf₂N]/Ammoeng 102 were optimised by response surface methodology (RSM). Optimal conditions were recommended as temperature between 55–60 °C, glycerol/oil amount between 1.8–2 mmol/2 mmol, [TOMA]·[Tf₂N] concentration less than 10%, reaction time 24 h, and lipase amount 15 wt.% based on oil mass. Under these conditions, the glycerolysis reaction resulted in reasonably high DG yield (∼70%) and TG conversion (∼90%).