Publications by authors named "Huseyin Erten"

Şalgam is a traditional drink produced via the lactic-acid fermentation of vegetables (black carrot and turnip), sourdough, and bulgur flour; with rock salt also added. During storage, an additional yeast-mediated fermentation can occur, causing changes in organoleptic properties, as evidenced by the microbe-mediated release of gases. Here, we characterise şalgam as a microbial habitat, identify the yeasts that cause spoilage, and characterise yeast-induced changes of the şalgam.

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Water kefir (WK) is a nondairy probiotic beverage produced using water kefir grains that are highly adaptable to diverse food substrates. Fruit and vegetables have been used more in beverage production in recent years due to their plentiful nutritional qualities. In this context, the aim of this study is to develop fruit-vegetable juice-based beverages fermented with WK grains in order to produce novel, non-dairy, probiotic water kefir-like beverages (W-KLBs) with improved sensory and nutritional properties.

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Executive Summary: Microbes are all pervasive in their distribution and influence on the functioning and well-being of humans, life in general and the planet. Microbially-based technologies contribute hugely to the supply of important goods and services we depend upon, such as the provision of food, medicines and clean water. They also offer mechanisms and strategies to mitigate and solve a wide range of problems and crises facing humanity at all levels, including those encapsulated in the sustainable development goals (SDGs) formulated by the United Nations.

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Article Synopsis
  • - The study aimed to create a new type of cheese, called "Ewiss cheese" (EC), using sheep milk while employing traditional Swiss cheese technology, producing two variations with raw milk (RM) and pasteurized milk (PM).
  • - Microbiological analyses showed no significant differences in lactic acid bacteria between the RM-EC and PM-EC, with both types having mainly mesophilic LAB cocci initially, but shifting to LAB rods after 9 months of ripening.
  • - The resulting cheeses had different textural properties and compositions—RM-EC had higher protein and lactic acid content, while PM-EC had more propionic acid, and both emitted 46 diverse volatile compounds.
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The dipeptide γ-glutamylcysteine (γ-GC), the first intermediate of glutathione (GSH) synthesis, is considered as a promising drug to reduce or prevent plethora of age-related disorders such as Alzheimer and Parkinson diseases. The unusual γ-linkage between the two constitutive amino acids, namely cysteine and glutamate, renders its chemical synthesis particularly challenging. Herein, we report on the metabolic engineering of the non-conventional yeast Yarrowia lipolytica for efficient γ-GC synthesis.

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This work was carried out with the aim to investigate the microbiological, physicochemical, and sensory properties of an innovative yoghurt produced from ewe's milk. Experimental yoghurt productions were performed with a commercial freeze-dried starter preparation and a natural milk starter culture (NMSC) of and . The two yoghurts did not differ for colour parameters, showing an average value of lightness, redness, and yellowness of 94.

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Fresh fruits and vegetables are susceptible to a large variety of spoilage agents before and after harvest. Among these, fungi are mostly responsible for the microbiological deteriorations that lead to economically significant losses of fresh produce. Today, synthetic fungicides represent the first approach for controlling postharvest spoilage in fruits and vegetables worldwide.

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In this study, the effect of five different Torulaspora delbrueckii strains in combination with an ale type Saccharomyces cerevisiae on physical, chemical, microbiological, aroma composition, and sensory profiles of beer were examined. The ethyl alcohol content of produced beers ranged from 5.46% (v/v) to 5.

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Yeasts are an important group of microorganisms and contribute to the fermentation of a broad range of foods and beverages spontaneously or as a starter culture. Rapid and reliable microbial species identification is essential to evaluate biodiversity in fermented foods and beverages. Nowadays, high-throughput omics technologies and bioinformatics tools produce large-scale molecular-level data in many fields.

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This research aimed to analyze variations in chemical properties, microbiological characteristics and generated volatile organic compounds (VOCs) profile during sourdough fermentation. Sourdoughs were collected from different cities in Turkey at two different times and lactic acid bacteria (LAB) in the samples were identified with culture-independent and culture-dependent molecular methods. According to culture-dependent methodology, thirteen LAB species were identified.

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Non-Saccharomyces yeasts have been suggested for use in wine production for lowering alcohol content. In this study, 23 non-Saccharomyces yeasts were investigated in laboratory-scale trials using previously frozen grape must. Both aerated and standard fermentation conditions were investigated and the fermentations were co-inoculated with a commercial Saccharomyces cerevisiae reference yeast strain.

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NaCl is utilized in Şalgam at 1-2% (w/w). The aim of this study was to reduce the NaCl content by addition of different concentrations of KCl and CaCl during production and evaluate their effects on quality. An innovation in production process was also employed, specifically dough extraction and use of the resulting liquid as a starter inoculum.

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Tarhana is produced at batch systems in which the microbiota has changed accordingly to the microbial load from ingredients. In order to stabilize the microbiota, the effects of backslopping carried out under different temperature regimes (25 and 30 °C), pH (3.70 and 4.

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Oleaginous microorganisms, such as , accumulate lipids that can have interesting applications in food biotechnology or the synthesis of biodiesel. yeast can have many advantages such as wide substrate range usage and robustness to extreme conditions, while under several culture conditions it can produce high lipid productivity. Based on this assumption, in this study, 12 different strains were used to investigate microbial lipid production using a glucose-based medium under nitrogen-limited conditions in shake-flask cultivations.

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Fermented chickpea liquid is used as a leavening agent in chickpea bread production. In the present study, traditional chickpea liquid starter and dough samples were collected from bakeries in Turkey and microbiologically investigated. Culture-independent analysis for microbiota diversity, performed by MiSeq Illumina, identified Clostridium perfringens as major group in all samples, while Weissella spp.

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Epiphytic yeasts were isolated from different cultivars of apples and lemons and identified by a combination of PCR-RFLP of 5.8S rRNA region and sequencing of D1/D2 domain of the 26S rRNA gene. Among 69 isolates, Aureobasidium pullulans GE17 and Meyerozyma guilliermondii KL3 strains showed the greatest antagonistic activity against two significant apple and lemon postharvest pathogens, Penicillium expansum DSM62841 (blue mold) and Penicillium digitatum DSM2750 (green mold), after preliminary screening.

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In the present study, a total of eight sourdough samples were collected from three different bakeries at two different times in Turkey. Also, laboratory-scale sourdough production was conducted by daily back-slopping for 7 days. Microbiological and chemical properties of the sourdoughs were investigated.

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Exopolysaccharide producing starter cultures enable manufacturing "clean labeled" foods with improved textural and nutritional properties. The structural and technological analyses were performed on the ropy exopolysaccharides of six The incubation temperature, time and pH affected the exopolysaccharide production and high exopolysaccharide was produced in the presence of sucrose and maltose. The viscosity of exopolysaccharide was high at acidic conditions except PFC311E that showed viscous at neutral pH.

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Citric acid (CA) productivity by Yarrowia lipolytica dependents on strain type, carbon source, carbon to nitrogen (C/N) molar ratio as well as physicochemical conditions (pH, temperature, oxygen transfer rate, etc.). In the current study, 10 different Y.

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Shalgam, a traditional red, cloudy and sour soft beverage, is produced by lactic acid fermentation of black carrot, sourdough, salt, bulgur flour, turnip and adequate water. The present study was designed to characterize the volatile compounds of shalgam obtained from different methods. The aroma compounds of shalgams produced by traditional and direct methods, and addition of Lactic acid bateria (LAB) cultures were examined.

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In this study, the yeast microbiota of naturally fermented black olives made from cv. Gemlik, grown in three different districts of the Çukurova region of Turkey, were investigated. Fermentations were conducted for 180 days in three different brines, including NaCl 10% w/v, NaCl 8% w/v and NaCl 8% w/v added with glucose 0.

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The present paper describes the behaviour of Lachancea thermotolerans and Saccharomyces cerevisiae in pure, co-cultured and sequential fermentations in cv. Emir grape must. Faster fermentation rates were observed in wine made with a pure culture of S.

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The antimicrobial action of chitosan against wine related microorganisms, including Lactobacillus plantarum, Saccharomyces cerevisiae, Oeonococcus oeni, Lactobacillus hilgardii, Brettanomyces bruxellensis, Hanseniaspora uvarum and Zygosaccharomyces bailii was examined in laboratory media. In order to assess the potential applicability of chitosan as a microbial control agent for wine, the effect of chitosan, applied individually and/or in combination with sulphur dioxide (SO2), on the growth of microorganisms involved in various stages of winemaking and on the fermentative performance of S. cerevisiae was investigated.

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Background: Shalgam is a traditional Turkish lactic acid fermented beverage. This study examined the microbial, chemical and sensory characteristics of shalgams produced by various methods.

Results: Different production methods using traditional method (dough fermentation and carrot fermentation), direct method (without dough fermentation) and with the addition of starter cultures were applied to produce shalgams.

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Isoamyl acetate is a natural flavour ester, widely used as a source of banana flavour by the food industry. Williopsis saturnus var. saturnus is a yeast which can produce isoamyl acetate by esterification of amyl alcohols with acetyl coenzyme A via fermentation.

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