Ismail Tontul

Necmettin Erbakan Üniversitesi · Department of Food Engineering

Background: Spray-drying is one of the highly utilized techniques to increase the shelf-life of food products. However, there are problems during spray-drying of sugar-rich fruit and vegetable juices due to the low glass transition temperature of sugars present in these products (Bhandari, Datta, & Howes, 1997). The sugars transform into a sticky f...

Alpha-linolenic acid (ALA) is an omega-3 fatty acid naturally occurring in plant oils. Omega-3 fatty acids have many beneficial effects. However, these fatty acids are sensitive to environmental factors such as heat, oxygen, metal ions, and humidity. Thus, these oils are microencapsulated by different methods. There are several methods for oil enca...

Saccharomyces cerevisiae var. boulardii have probiotic properties which are beneficial for human health. It has been commonly used as a drug against gastrointestinal disorders. S. boulardii has been used in some food formulations in recent years, due to its probiotic properties. However, it is not sufficiently stable for food processing and gastroi...

The objective of this study was to determine volatile compounds in green tea powders produced from a clone of two different teas (Camellia sinensis (L.) O. Kuntze) grown under different shade levels and harvested in two consecutive shooting periods. Both hydrodistillation and solid phase microextraction (SPME) methods were comparatively performed t...

Flaxseed oil, sensitive to oxidation, was systematically microencapsulated with six triple wall materials combinations [carbohydrate (maltodextrine and two different modified starches (N-Lok® and HiCap® 100)); protein (sodium caseinate, whey protein concentrate); and Arabic gum] for the highest microencapsulation efficiency and oxidation stability....

The fruit of sea-buckthorn (Hippophae rhamnoides L.) is a rich source of nutrients and phytochemicals. This study determined the chemical composition and antioxidant activity of sea-buckthorn grown in Issyk-Kul region, Kyrgyz Republic, during maturation from August to November. Three different assays [ferric reducing antioxidant power (FRAP), DPPH...

The study aimed to produce instant dried baker's yeast (BY) by conventional or infrared‐assisted refractance window drying (RWD or InfraRWD, respectively) and compare their bakery performance with commercial BY. According to the findings of the study, the total yeast count was higher than 9.60 log cfu/g in all dried BY samples, and the lowest viabi...

The growing globally interest in healthy nutrition has resulted in a significant progress in the development of specialised and novel dairy powders. Refractance window has received increasing attention as a novel food-processing technology that is used at laboratory and industrial scale for food dehydration. This study was conducted determine the e...

Carob is used as a source of sugar in many product formulations due to its naturally high sugar content. In addition, carob naturally contains a high content of D-pinitol. D-pinitol is an important food ingredient since it regulates glucose metabolism in the body and can be used in the diets of Type 2 diabetic patients. In this study, spreadable cr...

In this study, leather production was carried out using two different varieties of hawthorn (Crataegus orientalis var orientalis). Drying was carried out by two different methods (convective drying and vacuum drying) at three different temperatures (50, 60 and 70 °C). Color properties, moisture content, total phenolic content, total flavonoid conte...

In the present study, response surface methodology employed to optimize aqueous extraction conditions of oil bodies from pomegranate seeds. Additional studies conducted to increase the extraction yield and purification of oil bodies. The optimum conditions for the isolation were particle size lower than 1.6 mm, hydration duration of 48 hr, homogeni...

The preference for plant-based foods has been increased in recent years. Animal milk alternatives, named as plant-based milk, are produced from different oilseeds, nuts and cereals by a series of processing steps. These plant-based milk have different advantages over animal milk such as being lactose and cholesterol-free and having a high content o...

Cereal bars were coated with three different biopolymers to prevent the changes during storage. The edible coating using sodium alginate (SA), carboxymethyl cellulose (CMC) and whey protein isolate (WPI) had little effect on chemical properties of the bars. The moisture content of coated bars was found to be significantly higher than that of contro...

BACKGROUND In the present study, the usability of saponin rich extracts (soapwort and horse chestnut) was evaluated as a foaming agent for foam mat drying of pomegranate juice. RESULTS According to the foaming and stabilization studies, the optimum conditions were determined as 0.4% of soapwort extract, 0.03% of carboxymethyl cellulose (CMC) as a...

Membrane processing has gained much interest for clarification because of its many advantages. Ultrafiltration and microfiltration are the membrane processes that can be used for clarification. These processes provide high clarity in fruit juices and wines with minor effects on the quality of the juice. However, concentration polarization and membr...

BACKGROUND Determining plant tolerance to water stress is necessary in irrigation scheduling, deciding of supplementary irrigation, planning and operation and more importantly rational use of water resources. In this study, irrigation regime effects on oregano growth, water use, yield and quality parameters were investigated by using reduced irriga...

Functional and textural properties of fruit bars are susceptible to environmental conditions such as temperature, humidity and oxygen. This study aimed to prevent these changes by the edible coating of fruit bars using sodium alginate (SA), carboxymethyl cellulose (CMC) and whey protein isolate (WPI) during storage at two different temperatures. Th...

Grape pomace is a by-product that contains high amounts of phytochemicals such as phenolic acids, flavonoids, and anthocyanins. For the efficient extraction of these compounds, extraction optimization was done in the present study. Glycerol concentration, a cheap, non-toxic and abundant green solvent, and liquid–solid ratio were evaluated as the in...

The increase in consumers' demands for safer and healthier food has led to the development of many new products in food technology. For this reason, micro- or nanoencapsulation has become an important area in order to protect food components with functional properties against environmental conditions and to provide controlled release in recent year...

Dried products are widely used from the past because of their long shelf life, rich nutrient content and availability. Solar or shade drying methods have become the most widely used drying technique from past to date, due to no equipment requirement, cost and simplicity. However, this drying method has some disadvantages such as long drying time, c...

Drying is one of the oldest technique used for preservation of foods. Among different drying techniques, spray drying is one of the most highly used technique for liquid foods. In addition to its use as a preservation method, it also used for encapsulation of bioactive food components. As a heat involved technique, losses in heat sensitive bioactiv...

Fruit leathers are commonly produced with several fruits for consuming out of harvesting seasons. It is rich in nutritional and bioactive compounds. However, the bioactive compounds are sensitive to processing and storage conditions. Therefore, the chemical properties of the pomegranate leather produced by refractance window drying during storage a...

Encapsulation is a technology applied to cover an active material with various materials. In the food industry, encapsulation techniques are applied to protect sensitive components against environmental factors, increase bioavailability of nutrients, controlled release and mask flavor and odor. Nanocapsules are obtained when the size of the obtaine...

This study aims to investigate the effects of microwave, combined microwave/hot air treatment and hot air-only roasting on the formation of heat-induced contaminants of carob powders. Moisture content, water activity and pH values of the product decreased with the increasing roasting time and microwave power, while browning index (BI) and ultraviol...

Cornelian cherry is a wild fruit contains considerable amounts of bioactive compounds such as ascorbic acid, anthocyanins, and phenolics. It has many different health beneficial effects due to these bioactive compounds. In the present study, convective drying and refractance window drying was employed in cornelian cherry pulp drying under different...

Flavoured olive oil gained has importance in terms of its sensorial properties and oxidative stability in recent years. However, the water activity level of the flavouring agent can be important for oxidative stability. Therefore, the aim of this study was to determine the effect of the water activity of rosemary, which was used as a flavouring age...

The present study aimed to determine the effect of refractance window (RW) drying comparatively with freeze drying on some physical properties and microbiological properties of yoghurt powder. Physical properties of yoghurt powders obtained by RW drying were generally better than those of yoghurt powders obtained by freeze drying except for colour...

The present study aimed to optimize extraction and spray‐drying conditions used to produce rosehip tea powder from a blend of rosehip fruit and hibiscus. The optimum conditions of the extraction and spray drying processes were investigated using response surface methodology. The responses of the optimization were the ascorbic acid (AA) and total mo...

Kefir microencapsulation was optimised using Box–Behnken's response surface methodology. Product yield, moisture, water activity, bulk density, hygroscopicity, colour, wettability, solubility, particle size, pH, titratable acidity and microstructure were analysed. The viable counts of lactobacilli, lactococci and yeasts in the kefir microcapsules w...

Pestil (a kind of fruit leather) is a traditional Turkish product generally made from mulberry, grape, and apricot. It is a good alternative for unhealthy candies made from corn syrup and artificial colorant. However, in the traditional processing of pestil, fruit juice (which has 10–14°Bx) and other ingredients (honey, milk, etc.) are boiled in th...

In the present study, the effect of Refractance Window (RW) drying on the functional properties of chickpea protein isolates was investigated and compared to freeze drying at different pH levels. The functional properties investigated were protein solubility, water and oil holding capacity, emulsifying properties, foaming properties, flocculation a...

The present study examines the effects of various formulations (traditional and hydrocolloid) and drying techniques [hot air drying at 50, 60 or 70 °C, microwave-assisted hot air drying (90 or 180 W) at 50, 60 or 70 °C and refractance window drying 90, 95 and 98 °C), in order to develop new methods for pomegranate pestil production. Water activity,...

Abstract The leaves of harvested tea [Camellia sinensis (L.) O. Kuntze] can be processed into different products such as black tea, green tea and oolong tea. Black tea is the mostly consumed worldwide among these products. Black tea production is achieved by a series of processing steps namely withering, rolling, fermentation, drying, sieving and...

Flowered verticillasters of Sideritis lycia Boiss. & Heldr. and Sideritis libanotica Labill. subsp. linearis (Benth.) Bornm. are used as herbal tea. In the present study, these plants were tried to be cultivated and phenolic composition and antioxidant activity of the wild and cultivated plants were compared. Total phenolics, flavonoids and antioxi...

In the present study, black mulberry juice was concentrated using thermal evaporation and osmotic distillation after clarification and pasteurization. The main quality parameters of the concentrates were comparatively investigated after reconstitution with different storage times and temperatures. The parameters investigated were: color, turbidity,...

In the present study, the effectiveness of different vegetable proteins (pea protein isolate, soy protein isolate and zein from maize) at two different ratios (1% and 5%) on product yield and physical properties of spray-dried pulpy tomato juice was investigated. Additionally, these proteins were compared with whey protein concentrate which has a s...

Emulsification step of flaxseed oil microencapsulation was optimized using the Box-Behnken design of the response surface methodology in wall material concentration, oil loading and ultrasonic emulsification time. The optimization was performed to optimize the microencapsulation efficiency (MEE) and product yield (PY). Bulk density, particle size a...

This study aimed to determine the physicochemical properties of the green tea powders produced from 2 different Turkish tea [Camellia sinensis (L.) O.Kuntze] clones (Derepazarı 7 and Fener) grown under different shade levels and harvested during 2 consecutive shooting periods. Moisture, ash, crude fiber, and total phenolic contents of the green tea...

Salvia tomentosa is one of the common medicinal plants and consumed as herbal tea in some Mediterranean countries. It has been extensively collected from natural habitat and this regardless collection has being caused extinction of the plants recently. Therefore, present study was undertaken to cultivate S. tomentosa and compare phenolic compositio...

In the present study, the main quality parameters such as moisture content, extract yields, total essential oils, phenolic content and composition, and antioxidant activity of wild and cultivated Salvia fruticosa were elaborately investigated in six-month storage period for two consecutive years. The cultivated samples had higher total phenolic con...