In this study, seeds from the safflower variety called ''Dinçer'' were roasted and microwaved before oil extraction by cold pressing. Some physico-chemical analyses (moisture, ash, oil content and color) were performed in safflower meals. Physico-chemical properties (refractive index, viscosity, turbidity, specific gravity, color, free acidity, peroxide value, iodine number), nutritional components (total phenolics, antioxidant capacity, tocopherol content), sterol composition and fatty acid composition of produced oils were also determined. Volatile components of the oils were detected by solid-phase microextraction/ gas chromatography-mass spectrometry technique. Quantitative descriptive analysis was accomplished with trained panelists by 11 definition terms. Cold pressing yielded less oil than solvent extraction, but oil quality was superior and a refining process was not required. There was no significant difference between samples for fatty acid composition and some physico-chemical parameters. Whereas, microwave treatment caused a decrease in oil turbidity, free acidity, a-tocopherol and some sterol contents and an enhancement in total phenolic content, antioxidant capacity and peroxide value. Moreover, microwave treatment led to an increased nutty aroma in the oil. In contrast, isot pepper aroma was decreased by microwave treatment. This study provides very important information about the safflower oils for the first time in the literature.

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The yeast Kluyveromyces marxianus produces a range of volatile molecules with applications as fragrances or flavours. The purpose of this study was to establish how nutritional conditions influence the production of these metabolites. Four strains were grown on synthetic media, using a variety of carbon and nitrogen sources and volatile metabolites analysed using gas chromatography-mass spectrometry (GC-MS). The nitrogen source had pronounced effects on metabolite production: levels of the fusel alcohols 2-phenylethanol and isoamyl alcohol were highest when yeast extract was the nitrogen source, and ammonium had a strong repressing effect on production of 2-phenylethyl acetate. In contrast, the nitrogen source did not affect production of isoamyl acetate or ethyl acetate, indicating that more than one alcohol acetyl transferase activity is present in K. marxianus. Production of all acetate esters was low when cells were growing on lactose (as opposed to glucose or fructose), with a lower intracellular pool of acetyl CoA being one explanation for this observation. Bioinformatic and phylogenetic analysis of the known yeast alcohol acetyl transferases ATF1 and ATF2 suggests that the ancestral protein Atf2p may not be involved in synthesis of volatile acetate esters in K. marxianus, and raises interesting questions as to what other genes encode this activity in non-Saccharomyces yeasts. Identification of all the genes involved in ester synthesis will be important for development of the K. marxianus platform for flavour and fragrance production.

The objective of this study was to investigate and compare the effects of UV light and heat treatment on vitamins A, B(2), C, and E in cow and goat milk. Vitamins were analyzed by reverse-phase high-pressure liquid chromatography. Ultraviolet and pasteurization treatments caused loss in vitamin C in milk. Pasteurization did not have any significant effect on vitamin B(2). However, UV light treatment decreased the amount of vitamin B(2) after several passes of milk through the UV system. In addition, UV light treatment decreased the amount of vitamins A and E. Vitamins C and E are more sensitive to UV light. UV light sensitivities of vitamins were C>E>A>B(2). These results show that UV light treatment decreases the vitamin content in milk. Also, the number of passes through the UV system and the initial amount of vitamins in milk are important factors affecting vitamin levels.

In this study, roasted and unroasted (control) tomato seeds were cold pressed and the seeds, oils, and seed presscakes (meals) were analyzed. Some physicochemical properties, total phenolic content and antioxidant capacity, thermal properties, mineral contents, fatty acids, sterols and tocopherols compositions, volatile compounds and sensory evaluation of the tomato seed oils were determined. The tomato seeds contained 3.3 % of ash, 17.3 % of oil and 27.2 % of protein. The cold press oil recovery rate was 7.2 and 10.28 % for control and roasted seeds, respectively. There were eight sensory terms defining the oils together with 34 different aromatic compounds quantified. The volatile compounds furfural, hexanal, benzaldehyde and 2‐isobutylthiazole were found with the highest frequency in the samples. Roasted, green and tomato were defined as characteristic sensory terms for tomato seeds oils. Fifteen different minerals, melting and crystallization temperatures and enthalpies of the oil samples were also quantified. This study provides important data for the tomato seed oils, and proves that pre‐roasted tomato seed oils are high quality, nutritious and aromatics oils with higher levels of consumer acceptability.

In this study, cold press‐produced capia pepperseed oil samples were characterized. Pre‐roasting and enzyme treatment against control group (no pre‐treatment) were applied to the seeds prior to cold pressing, and the oil yield, meal, and oil quality parameters were examined. The physico‐chemical parameters (refractive index, viscosity, turbidity, specific gravity, color, free acidity, peroxide and iodine values, antioxidant capacity, total phenolic content, and energy value), components composition (fatty acid, sterol, and tocopherol), thermal parameters (melting and crystallization temperatures and enthalpies), volatile aromatics composition, sensory properties (Flavor Profile Analysis), and consumer perception (hedonic test) of the oil samples were accomplished. It was found that cold pressing is low in efficiency, and oil sensory quality and consumer acceptability levels were also low. Although pre‐roasted seeds yielded a little more oil and had better sensory quality, it was determined that these oils need at least a deodorization or a physical refining for acceptable sensory quality. Practical applications: The results of this study indicated that capia pepperseeds obtained as waste during vegetable processing can be used as an alternative source for cold pressed oils and a raw material for animal feed. Moreover, these seed oils have economical impact due to their essential fatty acid (linoleic acid, 71.13%), sterol, and tocopherol content. Based on the sensory findings, full or partial refining is recommended in order to increase the sensory quality of the pepperseed oil. The capia pepperseeds pretreated by roasting and enzyme applications were extracted by a cold‐pressing technique. It was shown that both treatments caused a decrease in antioxidant capacity, total phenol content, viscosity, and turbidity but an increase in oil yield and iodine number of the oils.

Bioflavours are called natural flavour and/or fragrance compounds which are produced using metabolic pathway of the microorganism and/or plant cells or their enzyme systems with bioengineering approaches. The aim of this study was to investigate bioflavour production from tomato and red pepper pomaces by Kluyveromyces marxianus and Debaryomyces hansenii. Obtained specific growth rates of K. marxianus and D. hansenii in tomato pomace were 0.081/h and 0.177/h, respectively. The bioflavour profile differed between the yeasts. Both yeasts can produce esters and alcohols such as phenyl ethyl alcohol, isoamyl alcohol, isoamyl acetate, phenyl ethyl acetate and isovaleric acid. "Tarhana" and "rose" were descriptive flavour terms for tomato and pepper pomaces fermented by K. marxianus, respectively. Tomato pomace fermented by D. hansenii had the most intense "green bean" flavour while "fermented vegetable" and "storage/yeast" were defined as characteristic flavour terms for pepper pomaces fermented by D. hansenii.

Ezine cheese is a white pickled cheese ripened in tinplate containers for at least 8 mo. A mixture of milk from goat, sheep, and cow is used to make Ezine cheese. Ezine cheese has geographical indication status. The purposes of this study were to determine and compare the changes in basic composition, aroma, and sensory characteristics, and proteolytic activity of Ezine cheese stored in tinplate containers and plastic vacuum packages during storage. Aroma-active compounds were determined by thermal desorption gas chromatography olfactometry. To evaluate the proteolytic activity, casein and nitrogen fractions were determined. The results indicated that compounds identified at high intensities were dimethyl sulfide, ethyl butyrate, hexanal, ethyl pentanoate, (Z)-4-heptenal, 1-octen-3-one, acetic acid, butyric acid, and p-cresol. Characteristic descriptive terms were cooked, whey, creamy, animal-like, sour, and salty. The level of proteolysis increased in Ezine cheese during storage. Ezine cheese can be ripened in small-size packaging after 3 mo of storage. Approximately 6 mo is sufficient to produce the characteristic properties of Ezine cheese.