Ilkay Koca

Ondokuz Mayıs University · Department of Food Engineering

Artemisia L., belonging to the Anthemideae family, encompasses over 500 species. These plants, which can grow as perennial and biennial herbs or small shrubs, are found in Asia, Europe, and North America. Species of Artemisia exhibit anti inflammatory, antitumor, antispasmodic, antimicrobial, insecticidal, antimalarial, and antioxidant activities....

In recent years, red‐fleshed apple has attracted a lot of attention due to its pleasant appearance, taste, and being a valuable source of anthocyanins. Generally, different types of this apple are known as ornamental apple plants that are rarely found in various regions around the world like New Zealand, Kazakhstan, Kyrgyzstan, Australia, China, an...

Bioactive compounds are substances obtained from natural sources such as plants, microorganisms, animals, and marine organisms, and they exhibit various beneficial health effects, including antihypertensive, anticancer, and anti-inflammatory properties. Traditional extraction methods typically involve the use of toxic and environmentally harmful or...

Chestnut (Castanea spp.), throughout history, is a tree species of interest both as a food source and for its positive effects on health. Chestnut trees are significant in ecological, economic, and cultural terms. They have spread across various regions of Europe, America, and Asia. In recent years, the area occupied by chestnut trees worldwide has...

Kefiran is an exopolysaccharide with multiple hydroxyl groups produced by lactic acid bacteria found in kefir grains. More than half of the dry kefir grain weight consists of kefiran. This edible biopolymer, which has approximately equal amounts of D-glucose and D-galactose in its structure, is water-soluble. Kefiran can be obtained by extraction f...

Orchids, one of the largest families of flowering plants, are cultivated for various purposes, including ornamental use, medicinal products, and food. In Turkey, the tubers of naturally occurring orchid species such as Ophrys, Orchis, Himantoglossum, Serapias, Anacamptis, Compreria, Barlia, Dactylorhiza, Aceras, and Neotinea are utilized in the pro...

In the last two decades, ionic liquids (ILs) that have garnered significant interest in the field of green chemistry have been gradually replaced by deep eutectic solvents (DESs) as more environmentally friendly alternatives. DESs are liquid systems composed of two or more safe components that form a eutectic mixture. Despite their attractive advan...

Natural deep eutectic solvents (NADESs) are a sustainable and green solution for the recovery of food ingredients such as pigments. In this work, the extraction conditions to obtain the maximum anthocyanins from blackberry fruit were investigated using NADES composed of choline chloride-acetic acid (CHAC) as the green solvent. The central composite...

Pigments/colorants including betalains, anthocyanins, carotenoids, and curcuminoids are widely used in food, pharmaceutical, and cosmetic sectors. The increasing interest in natural pigments is related to their biological properties and safety. Deep eutectic solvents (DES) emerged as sustainable and promising solvents for the extraction of bioactiv...

Date plum (Diospyros lotus L.) fruits are a good source of bioactive compounds and antioxidants. Drying can increase the shelf life of the fruit and its applications in the food development industry. Optimizing the drying conditions can help to produce prime-quality dried date plum fruits and conserve nutrients including phytochemicals. This study...

Black rosehip (Rosa pimpinellifolia L.) fruit is a rich source of anthocyanins and has been promoted for several bioactive properties. Drying this fruit can increase its shelf life and enhance its applications in functional food products. This study aimed to optimize the microwave drying process of black rosehip fruit. The process was optimized bas...

Deep eutectic solvents (DESs) are the next generation of green solvents that are considered for their stability and biocompatibility. This study used 10 different DESs synthesized from choline chloride, alcohols, organic acids and sugars. Red beet betalains were extracted using three conventional solvents and DESs. Characterization experiments of D...

The wild Foxtail lily (Eremurus spectabilis) is a valuable vegetable consumed in different forms as food and employed as a remedy for preventive and curative purposes. In the present study, the physicochemical and antioxidant properties and the volatile compounds of the leaves and stem parts of wild Foxtail lily were determined. The moisture conten...

Sumac (Rhus coriaria) is a flowering plant that is widely consumed for its promoting health benefits and used in food preparations as a spice in the Mediterranean region. It is a high shrub or small tree with imparipinnate leaves, villus and red fruits with one-seeded drupe, and small greenish-white flowers. The nutraceutical and pharmaceutical pot...

Cornelian cherry (Cornus mas L.) is a rich source of (poly)phenols such as phenolic acids, flavonoids, and anthocyanins that are known for their bioactivity. This study aimed to enhance the industrial applications of this cherry's pulp as a potential functional food ingredient. Foam-mat drying was used to produce cherry powder from cherry pulp. The...

ABSTRACT Red beet (Beta vulgaris L.) is a biennial plant belonging to the goosefoot (Amaranthaceae) family. It is a vegetable whose tubers and leaves are used throughout the world. Its cultivation areas extend to Europe, America and India. In Turkey, it is produced mostly in the Aegean and Marmara regions, and in small amounts in the Mediterranean...

ABSTRACT One of the most important quality criteria affecting the preferability of foods is color. For this reason, coloring agents are used in the food industry to obtain the desired color or to increase the existing color. However, given the side effects and toxicity issues of some synthetic colorants, consumers worldwide are showing increasing i...

In recent years, the increasing awareness of environmental degradation has led to the momentum in "green extraction" research within scientific and industrial fields. These studies signify an important area for the development of eco-friendly extraction techniques and the discovery of new solvents. In this context, deep eutectic solvents (DES) have...

Betalains are water-soluble pigments used as natural colorants in the food industry. Betalains, which have antioxidant, hepatoprotective, anticarcinogenic, antibacterial, and anti-inflammatory activities as well as coloring potential, are also considered natural nutritional supplements and food additives in the food industry. Nowadays, due to their...

In recent years, new practices and technologies that increase efficiency and quality have been developed to reduce waste and improve the quality of processed foods. Laser-based technologies have shown significant potential in improving the quality and safety of foods. Laser beams has a versatile use in the metal, ceramics, glass and food industries...

In recent years, medicinal plants have begun to attract worldwide attention. One of these plants, the genus Cyclopia (family Fabaceae), is a shrub that grows in the Cape Fynbos region of South Africa. Some Cyclopia species such as Cyclopia subternata, Cyclopia intermedia, Cyclopia sessiliflora are used in the production of honeybush tea. Cyclopia f...

Many applications have been developed as alternatives to traditional production in food processing. The common purpose of these applications is to protect and increase the quality of the products. Microfluidization is a new technique that has been used in foods since the early 1980s. Microfluidization, which is widely used in the pharmaceutical and...

Edible flowers have had an important place in human nutrition since ancient times. Nowadays, globalization and consumer awareness and increasing interest in healthy natural foods have made edible flowers popular again. Many different types of flowers have been used as both food and medicine in alternative medicine in different cultures. Nowadays, i...

Mangiferin, mango meyvesinin kabuk, sap, yaprak, kabuk ve çekirdeklerinde bulunan bir ksantondur. Geleneksel tıpta farklı kültürler, kardiyovasküler hastalık, diyabet, çeşitli enfeksiyonlar ve kanser dahil olmak üzere bir dizi hastalığın tedavisinde mangiferin açısından zengin bitkilerinden yararlanmaktadırlar. Çin, Küba ve Doğu Asya'da magniferin...

Garlic, onions, and leeks are vegetables that belong to the Allium family and are widely consumed all over the world. Leeks are grown in temperate regions of the world, including Europe, Asia, North America, and Africa. Turkey has an important place in terms of the production amount of leek and other Allium vegetables (garlic, onion, etc.). Along w...

Drying is one of the oldest food preservation methods. By reducing the water activity through drying, microbial and enzyme activation is limited, thus extending the shelf life of foods. Until today, many methods have been tried in drying fruits and vegetables. Very few of these are used to dry products in liquid form. Freezing, spraying, and foa...

In this study, the quality and antioxidant properties of three plum cultivars wildly grown in Turkey including Blackthorn (Prunus spinosa), Karaca (Prunus domestica var. karaca) and Üryani (Prunus domestica var. uryani) were investigated. For the outer shell, the lowest L*, a* and b* values were found in blackthorn (15.47, 2.59 and 1.77, respective...

The gülfatma flower (Alcea apterocarpa Fenzl Boiss) is used as remedy to treat many diseases since centuries. In this study, biosolvents such as glycerol, 1,3-butanediol, and ethyl alcohol were used extract and optimize anthocyanin s from gülfatma flower by applying the central composite of response surface methodology (RSM) considering temperature...

The tamarillo or tree tomato fruit (Solanum betaceum Cav.) is one of the most consumed fruits in the tropical countries. This fruit contains a numerous health benefits for human consumption. However, this fruit is perishable and its compositions are degraded under different heat conditions. Therefore, this study is sought to evaluate the mathematic...

Black rosehip (Rosa pimpinellifolia L.) is the purplish or black edible fruit of the plant, which is in the form of a bush, belonging to the Rosaceae family. This fruit, which is less common in Turkey than other rosehip species, is an industrial pigment design due to its high anthocyanin content. Due to the high amount of vitamin C contains, phenol...

Black rosehip (Rosa pimpinellifolia) is a fruit that grows naturally in Turkey and is not well known among the public. This fruit is rich in bioactive compounds such as anthocyanin and vitamin C. This study was carried out to determine the changes in bioactive properties during convective drying of black rosehip fruit. For this purpose, fruits were...

Date plum (Diospyrus lotus L.) is an edible fruit from the Ebenaceae family, rich in nutrients, and having tremendous medicinal properties. This paper attempted to show the influence of different parameters of convective drying such as temperature (50, 60, 70, and 80°C) and air velocity (0.5, 1.0, and 1.5 m/s) on the shrinkage and microstructure, r...

Autumn olive berries (AOBs) are a good source of natural antioxidants and compounds associated with protective effects on health. The current study investigated the possible impacts of the convective drying process on textural, morphological, phenolic compounds, and antioxidant properties of AOBs. Four drying temperatures (50, 60, 70, and 80 °C) in...

Bitter melon (Momordica charantia) is a rich source of phytochemicals including phenolic compounds with diverse health-promoting benefits and potential food industry application due to their antioxidant potential. Bitter melon leaves have been limitedly investigated in comparison to bitter melon fruits. The current work explores the use of green ex...

In the present study, we investigated and compared the effect of microwaves and freeze-drying methods on the dehydration and rehydration kinetics in the phenolic, anthocyanin, aroma profiles, and antioxidant properties of tree tomato fruit (Solanum betaceum). The tree tomatoes were dried using microwaves at 350 W, 500 W, and 650 W, and then freeze-...

Rosmarinic acid is the ester, of caffeic acid and 3,4-dihydroxyphenyllactic acid. It was isolated and purified from rosemary for the first time. Rosmarinic acid is one of the active ingredients of the plants belonging to the Laminaceae and Boraginaceae families, such as rosemary (Rosmarinus officinalis L.), basil (Ocimum basilicum), thyme (Origanum...

The appearance and color of foods are among the features that affect the consumer's preference. Color loss may occur in many stages, such as processing, storage, distribution, and marketing of foods, and colorants are used to mask the colorloss and increase its attractiveness. The most important of these colorants are betalains. Betalains are water...

Kynurenic acid is a substance detected in urine for the first time in 1853 by Liebig. It is found in human blood and peripheral organs of the body. The concentration of kynurenic acid in the body increases in some diseases (such as schizophrenia, Alzheimer’s disease, meningitis, autoimmune diseases and inflammation), while it decreases in others (s...

The processing of maize generates a considerable amount of maize husks which might have biological activities since most of the waste or by‐products are rich sources of bioactive compounds. Nonetheless, no study has investigated the phenolic compounds of maize husk extracts and the feasibility of encapsulating the phenolic compounds of maize husk....

West African countries have made impressive progress in fighting against malnutrition and hunger and ensuring food quality and varying food choices. This paper aimed for the first time to evaluate the determinants of diet choice by the populations of West Africa, especially those of Benin, Togo, and Nigeria. The data collected from 473 people relat...

Borage is used traditionally in folk medicine for centuries and is reputed in many ancient civilizations. This paper examined the effectiveness of natural deep eutectic solvent (NADES) based on choline chloride and glycerol (CHGLY) for the extraction of phenolic compounds from borage. The results showed that NADES was significantly more efficient t...

The aluminium (Al) can cause health problems to human being at overdose. The black tea is among the most common beverages in the world but may contain higher amount of Al. This study was conducted to determine Al content in black tea produced in Rize, Tabzon and Giresun/ Turkey and amount of Al transferred into tea infusions. Tea infusions were pre...

Molokhia, Corchorus olitorius , is a popular leafy vegetable, known in many world regions as a good source of nutritional and medicinal properties. Due to its short shelf life and the limited harvesting time, processing such as drying techniques permit to preserve and provide it throughout the year. In the present study, it was attempted to reveal...

Sumac (Rhus coriaria L.) is a traditional spice worldwide prized for its taste, odor, color, and promising bioactive compounds. The acidic natural deep eutectic solvents (NADESs) constituted of choline chloride with lactic acid (CHLA), acetic acid (CHAC), and tartaric acid (CHTA), and an addition of 20% water in the NADESs were tested for their eff...

This article provides the socio-cultural, health benefits and descriptive overview of common traditional fermented food products in Benin Republic. A wide range of indigenous fermented foods locally named Tchoukoutou, Tchakpalo, Gowé, Agbelima, Mawè, Ogi, Lafoun, Afitin, Iru, Sonru, Lanhouin, Gari and Dèguè is produced in Benin Republic. These food...

Scopoletin is a phytochemical of coumarins distributed in some plants. The aim of this study was the evaluation of scopoletin content and antioxidant activity of nettle, mallow, purslane, knot-grass, dill and coriander encountered in Black Sea regions. Analyses were conducted on the leaves and stems of these plants, except knot-grass. The lowest sc...

The aim of this study was to investigate and optimize lycopene extraction from autumn olive berries (AOBs). First, the best solvent mixture (hexane:acetone:methanol) was selected using Simplex-Lattice Design (SLD). After that, the conditions of extraction (temperature 20-60 °C, fruit-solvent ratio 1:10-1:70, and time 5-45 min) were optimized using...

Kinkeliba (C. micranthum) is a tropical plant widely used for its tremendous phytochemicals and biological activities. In the present study, three green carboxylic acid-based natural deep eutectic solvents (NADESs) were used to assess the extraction of phenolic compounds in terms of total phenolic content (TPC), total flavonoid content (TFC), indiv...

Natural deep eutectic solvents (NaDESs) are new green solvents used for the extraction of phenolic compounds. In this work, an efficient and greener strategy for extracting blackberry anthocyanins using NADESs was investigated. Sixteen NADESs constituted of choline chloride-urea, choline chloride-sugars, choline chloride-organic acids, choline chlo...

Pine resin has been used as a traditional health-promoting medicinal food in Turkey and some countries for centuries. In the present study, the antioxidant potential and the monoterpene profile of 13 pine resin samples purchased from herbalists in different provinces of Turkey were investigated. According to the analysis results, there were differe...

Vitus labrusca L. is a fragrant grape variety that is widely grown in our country and the world. In addition to being consumed as a table grape, it is also consumed by processing into different products such as wine, vinegar, and molasses. This fruit and its residues, revealed after processing into the product, are rich in phenolic compounds. The r...

Borage flower (Echium amoenum), an annual herb native to the Mediterranean region, is an excellent source of anthocyanins and is widely used in various forms due to its biological activities. In the present study, a choline chloride and glycerol (CHGLY)-based natural deep eutectic solvent (NADES) was applied in order to extract the anthocyanins fro...

This study was aimed to be produced rosehip vinegar production from rosehip fruit, which has a limited usage, for the first time, and to monitor in detail the changes in bioactive compounds and volatile compounds, which affected on aroma property of it, during the rosehip vinegar production. Thus, it was aimed to contribute to the modernization of...

Autumn olive fruits were osmo-dehydrated in sucrose solution at 70 ◦C under vacuum and atmospheric pressure. The mass transfer kinetics data were applied to the models of Azuara, Crank, Page, and Peleg. The Peleg model was the best-fitted model to predict the water loss and solid gain of both treatments. The vacuum application decreased the effecti...

Black rosehip (Rosa pimpinellifolia L.) is an edible fruit belonging to the large Rosaceae family. Processing this and similar fruits that have low water into vinegar generates added values. Besides, vinegar consumption has beneficial effects on human health. This study aimed to produce vinegar with enormous functional properties from the black ros...

Gum arabic, also known as acacia gum, is a natural gum that consists of solidified soda from various types of acacia trees. Initially, gum arabic was collected from Acacia nilotica, now called "gum arabic tree", mainly Acacia senegal and Vachellia seyal. It is a biopolymer composed of arabinogalactan, arabinose and galactose monosaccharides.

Lycopene is a red coloring carotenoid found in many fruits and vegetables. It is an important nutrient in the human diet due to its functional properties. In the present work, 9 lycopene sources, including Juliet tomato (JT), Cherry tomato (CT), Tomato (TO), Red Persimmon (RP), Grapefruit (GF), Watermelon (WM), Rosehip (RH), Yew fruit (YF) and Autu...

Chestnut flowers were obtained from different cultivars in and around Samsun city (Turkey). Teas were prepared by the infusion of 2 g of chestnut flowers in 100 ml of hot water (≈ 95°C). At different time duration (5, 15, 30, 45, and 60 min), an aliquot of tea samples were taken for analysis. Sensorial analysis was realized by 12 panelists evaluati...

Medicinal plants refer to plants or plant products used by humans in the treatment of diseases. Medicinal natural products are widely used in Sudan and are also commonly consumed in Africa and worldwide. The large numbers of the indigenous populations refer to the traditional medicinal plants for primary health care. The utility of these plants is...

Rosehip fruits are considered as functional foods and their teas are recommended as a great antioxidant source. In the present study, we aimed to evaluate the antioxidant properties of the teas of R. canina and R. pimpinellifolia obtained at different solid to liquid ratios. The infusions were prepared by mixing 1.5, 2 and 2.5 g of dried fruit with...

Rosehip species are used for different purposes and are valuable industrial food products. The physical, chemical, and antioxidant characteristics of dog rose (yellow and red ripening stages) and black rosehips were investigated in the present study. The greatest fruit length was detected for red rosehip, while the greatest width and highest flesh...

Gülhatmi (Alcea apterocarpa (Fenzl) Boiss) is a medicinal plant with attractive flowers whose color is one of the characteristic criteria to distinguish the species. In the present study, the physico-chemical and antioxidant properties of shade-dried white, pale pink, purple, red and black Gülhatmi flowers collected from Samsun province (Turkey), w...

Guava (Psidium guajava) is a small tree in the myrtle family (Myrtaceae), found in the tropical and subtropical regions. It gives an oval yellowish to greenish fruits with reddish pulp. Due to its appealing tastes (sweet, sour), it can be eaten fresh or processed as juice, jam, jelly or other common tropical fruits recipe.This precious fruit is lar...

The usages of plants play key roles in people’s daily life since they can be associated with culture, tradition, heritage, economy and health. In this study, the total phenolic content (TPC) and antioxidant activity of eight plants collected from Benin Republic including Hibiscus sabdariffa, Hibiscus acetosella, Caesalpinia pulcherrima, Manihot esc...

Tree tomato (Solanum betaceum), also called Tamarillo, is a small oval purple or purple yellowish fruit. It is commonly used as a dessert or an ingredient in some tropical cuisines. Generally, the tree tomato is popular in tropical and subtropical regions especially in Rwanda, Kenya, Equator, Peru, New Zealand, Australia, etc. Recently, this fruit...

Marshmallow is an annual or perennial medicinal plant distributed throughout the World, especially in Western Palearctic North Africa Mediterranean Europe, France, Britain the Balkans, Southwest and Central Asia as well as Southern Russia Marshmallow is not only used as food ingredients but also as a preventive and curative remedy for the treatment...

Cornsilk is maize waste containing phenolic compounds. In this study, freeze-drying, spray-drying, and microwave-drying techniques were evaluated for the encapsulation of cornsilk's phenolic compounds using maltodextrin as wall material. The results of antioxidant properties showed that freeze-drying was more efficient than microwave-drying and spr...

Autumn olive is a rich source of carotenoids, phenolic acids and flavonoids and is used for the prevention of many diseases. The effects of drying conditions on the functional properties of autumn olive were investigated for the first time. The optimum drying conditions were 81°C and 1 m.s‐1 to have the maximum experimental values of 6378.98 mg GAE...

Autumn olive fruits are a rich source of nutrients and functional compounds, making them functional foods against many diseases and cancers. To increase the consumption, its processing, and its transformation into new products would help spread them to the consumer’s table. In this study, after giving an overview of the physicochemical characterist...

Medicinal plants have been used for medical objectives since ancient times due to their beneficial properties, and their uses continue to this day. The Cornelian cherry fruit (Cornus mas L.) is considered to be one of those medicinal plants with important nutritional and therapeutic properties. It has been also used for different medical purposes i...

Rosa pimpinellifolia, commonly known as the burnet rose, has shown huge functional properties and industrial potential. In this present study, the convective drying process was optimized to enhance the quality, antioxidant activity, and phenolic compounds. The influence of drying conditions on the drying and rehydration kinetics and mathematical mo...

Dog rose (Rosa canina L.) is a rosehip used for domestic and industrial purposes. It has great antioxidant compounds such as lycopene and phenolic compounds. In the present study, technological processing was investigated to formulate a functional tea with great nutraceutical compounds. The drying conditions were optimized to have maximum antioxida...

In this work, optimum ohmic heating assisted hydrodistillation (OAHD) conditions for extraction of cinnamon (CEO) and bay leaf (BEO) essential oil were determined by response surface methodology (RSM). OAHD were compared with conventional hydrodistillation (HD). Hydrodistillation time (30–120 min), mass of sample (20–40 g) and voltage gradient (7.5...

Rosa pimpinellifolia L. fruits (RPF) have great industrial potential due to the high presence of anthocyanins. In this work, microwave-assisted aqueous two-phase extraction (MA-ATPE) was applied to simultaneous extraction and purification of anthocyanins from RPF with ethanol/ammonium sulfate aqueous two-phase system (ATPS). MA-ATPE process was opt...

Fruits are important for the daily diet as they contribute to the daily intake of macro and micro-nutrients such as fruits carbohydrates, fibers, potassium, folate, vitamins, proteins, carotenoids and polyphenols. The fruits contain phytochemicals which act as antioxidants as well as bio-functional components. Tropical fruits are well known for the...

The gluten-free food market is increasing day by day due to health problems or consumer preferences. However, studies show that gluten-free bakery products are nutritionally inadequate and/or expensive, in general. In the study, it was aimed to develop a gluten-free bakery product based on cornbread by using anchovy, which is a cheap and quality pr...