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This study was carried out to characterize antioxidant activity, total phenolic content, and the phenolic and flavonoids profile of postbiotic of Pediococcus acidilactici and to evaluate the effects of postbiotics (10% and 50%) alone and in combination with chitosan coating (1%) on the microbial and chemical quality of chicken breast fillets during storage at 4 °C. Antioxidant activity and total phenolic content of the postbiotics were found to be 1291.02 ± 1.5 mg/L TEAC and 2336.11 ± 2.36 mg/L GAE, respectively. The most abundant phenolic was vanillic acid, followed by t-caffeic, gallic, and caftaric acids. The postbiotic-chitosan (50% + 1%) combination decreased L. monocytogenes and S. Typhimurium counts by 1.5 and 2.1 log10 CFU/g, respectively, compared to the control (P 0.05). Postbiotic treatment did not significantly change the pH values and color properties of the breast fillets (P > 0.05). Postbiotic-chitosan combinations extended the shelf-life by up to 12 days compared to the control. In conclusion, the postbiotic-chitosan combination can be used to preserve and improve the microbial quality of chicken meat products.

Peptides responsible for bitter taste may form, as a result of the hydrolysis of protein-rich foods. The perception of bitterness is formed by the stimulation of bitter taste receptors and the interpretation of the signal sent to the brain through the nervous system. Dairy products are often characterized by bitter peptides. In studies conducted, it has been stated that the bitter peptides identified in cheese are generally originated from αs1- and β-casein. The bitter taste intensity of protein hydrolysates varies depending on the hydrophobicity of the peptide, the number of hydrophobic amino acids and its the chain length. While accelerating ripening in cheeses, methods including aminopeptidase, carboxypeptidase and adjunct cultures with starter culture have been used recently to prevent the formation of bitter taste defects. In this review; the formation and perception mechanism of bitter peptides has been explained and current studies on bitter removal methods have been presented.

Four different types of yoghurt were manufactured using purple basil which was added to milk as water extract or powder forms at levels of 1.0 % and 0.4 % (w/w). Physicochemical and rheological properties, antioxidant capacity, color and total phenolic contents of yoghurt samples were measured during 21 days of storage. None of changes were observed for titratable acidity, pH and hardness parameters of yoghurt samples; however, some changes were observed during storage. The contents for total phenolic compounds and antioxidant activity [2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid diammonium salt (ABTS+*) and 2,2-Diphenyl-1-picrylhydrazyl (DPPH*) values] were dramatically higher in powder-added yoghurt samples than those of its water extract counterparts, while the lowest total phenolics and ABTS+* were observed in control sample during storage. The values for storage and loss modulus were higher in water extract-added samples than powder-added counterparts. In conclusion, no significant effect of the addition of powder or water extract of basil was observed on gross chemical characteristics of yoghurt, while use of basil powder positively contributed to antioxidant activity and changed the rheological behavior of yoghurt gel.

Adjunct cultures including lactobacilli play important role in cheese proteolysis and bioactivity including Angiotensin Converting Enzyme (ACE)-inhibition and antioxidant activity. Four species of lactobacilli was used in the manufacture of model cheese and these were salted at different levels and the resultant cheeses were ripened at different time and temperature to understand the effect of salting and ripening conditions. The effects of the use of various of lactobacilli (Lactobacillus casei, Lb. helveticus, Lb. delbrueckii ssp. bulgaricus and Lb. plantarum), salt concentrations (1, 2, 3, 4 and 5%), ripening times (1, 30, 60, 90 and 120 days) and temperatures (5, 10, 15 and 20 degrees C) were investigated. The experiments were designed to determine the optimal salt concentration, ripening times and temperatures for optimal proteolysis, the highest levels of ACE-inhibition and antioxidant activity. The highest level of proteolysis and ACE-inhibiting activity in the model cheese was observed when ripening temperatures were between 8 and 16 degrees C, salt concentration at 2.5-3.0% and with a ripening period of about 60 days. The use of each lactobacilli contributed to the proteolysis in different manner; for example, ACE-inhibiting activity and antioxidant activity in the model cheese.

International audience; Bouhezza is an Algerian traditional cheese made using different types of milk (goat, sheep and cow), ripened in a goat-skin or sheep-skin bag called Chekoua or Djeld of Bouhezza. The objective of the study was the characterization of Bouhezza cheese through ten cheese preparation trials using goat raw milk. The chemical and microbiological composition and proteolysis were monitored on ripened samples. The physicochemical characteristics showed that Bouhezza is acidic with a pH value of 3.95 and 2.36% for titratable acidity as lactic acid, 13.20% for protein and 12.74% for fat. At the end of ripening, Bouhezza was classified to be a ripened, soft and mid-fat cheese. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of Bouhezza samples showed low proteolysis after 30days of ripening. Microbiological results showed a high content of lactic acid bacteria (LAB), 8 to 9 log cfu/ g, an absence of pathogenic bacteria, and a low level of contamination flora. This makes the cheese a healthy product and of an acceptable hygienic quality. Four proteolytic lactic acid bacteria were identified by 16S ribosomal deoxyribonucleic acid (rDNA) sequencing: two strains of Enterococcus faecalis, one E. faecium, and one Lactobacillus paracasei ssp. paracasei. Reversed phase-high performance liquid chromatography (RP-HPLC) of the soluble fraction at pH 4.4 showed changes occurred during ripening. This work highlights, characterizes, and improves the knowledge of cheese Bouhezza made with raw goat's milk. This product is rich in nutrients, such as proteins and minerals, that are useful to the consumer.

Full Text Article, Changes in sugars, organic acids and volatile compounds (VC) of red pepper flakes (RPF), traditional (TRI), and industrial (INI) isot peppers were evaluated during one year storage at the room condition. The changes in the flavor components were significantly affected by the production methods and storage time. Glucose content decreased gradually along storage and reduced by about 21.23, 47.22 and 56.65% for TRI, INI and RPF, respectively. However, fructose decreased significantly only in RPF (11.29%). Citric and succinic acids exhibited slight changes, but malic acid showed an increasing trend, especially in RPF (4-fold). Most of the VC in all samples decreased or disappeared after storage. The major quantitative losses in these compounds were found in TRI during the first 3 months as 81.76%. The storage was found to be caused deterioration flavor properties in red pepper spices and revealed the importance of appropriate storage conditions.

Bouhezza is an Algerian cheese, which is ripened in a goat-skin bag, called Chekoua. The aim of the study was to determine the protein profiles and aromatics, which contribute to sensory properties of Bouhezza cheese. The chemical composition, proteolysis, and volatile profile have been carried out in cheese made from raw goat milk. The results showed that, the dry matter ranged from 23.07 to 51.95%, the fat-in-dry matter ranged from 10.58 to 31.77%, and the protein ranged from 28.27 to 42.09%. Water-soluble and 12% trichloroacetic acid-soluble nitrogen fractions decreased at the beginning of the ripening process and then they increased until the end of ripening. The reverse phase-high-performance liquid chromatography peptide profiles of the cheese showed the modifications occurred during the ripening process. The volatile compounds showed a diversity of odorous components which contribute to give to the cheese its particular organoleptic. There were 109 compounds identified in Bouhezza cheese. C...

The effects of partial substitution of goat's milk for sheep's milk, scalding and dry salting on the proteolysis of Urfa cheese were monitored for 240 days. For this reason, the contents of total nitrogen, water‐soluble nitrogen (WSN), and trichloroacetic acid‐soluble nitrogen (TCA‐SN) were explored as well as the chemical compositions of samples during ripening. Also, RP‐HPLC of pH 4.6‐soluble, 70% ethanol‐insoluble (EtOH‐i), and urea‐PAGE of pH 4.6‐insoluble nitrogen fractions of samples was determined. The results showed that the effects of partial substitution of goat's milk for sheep's milk on WSN and TCA‐SN were significant from sixth to eighth month of the ripening, respectively. Even though the effects of the milk type, dry salting, and scalding on the peptide profile were significant at the beginning of maturation, the peptide profile of cheeses was almost similar at the end of the storage. Furthermore, the proteolysis of Urfa cheese was limited due to dry salting during the ripening. PRACTICAL APPLICATIONS: The maturation of cheese is a complex biochemical process involving the hydrolysis of fat, breakdown of protein, and metabolism of lactose. Though the biochemical reactions during cheese ripening are not precisely understood, proteolysis is one of the most significant biochemical processes during maturation. It is known that the amino acids resulting from proteolysis are the precursors of flavor components in cheese. Milk itself is a significant source of proteolytic enzymes. And also, the curd scalding temperature and salt content of cheese affect the proteolytic activity during cheese ripening. However, limited proteolysis may be occurred during the cheese maturation due to dry salting and scalding process. Therefore, studies should focus on overcoming this problem. This study can help to overcome the limited proteolysis in the production of cheese. Also, results from the study may contribute to the industrial production of Urfa cheese.

The effect of aromatic herbs on the RP-HPLC peptide profile, angiotensin I-converting enzyme-inhibitory (ACE-i) activity, antioxidant capacity and volatile compounds in artisanal cheeses was investigated. Three representative artisanal cheeses (white brined, beaten and Kashkaval cheeses) were produced using aromatic herbs (Mentha longifolia, Origanum vulgare, Thymus longicaulis, Alium sativum, Petroselinum crispum, Capsicum annuum). Compared with control group, herbal cheeses (except white cheese with garlic and parsley) revealed a significant increase in antioxidant activity. The highest ACE-i activity was noticed in 60 days of ripening with a mean value of 98.72% in goat beaten cheese and 97.78% in Kashkaval cheese enriched with peppers. One hundred and one volatile compounds, mainly acids, esters and alcohols, were identified in significantly higher amounts in cheeses made with herbs and contributed to the development of the overall aroma perception.

The angiotensin-converting enzyme (ACE)-inhibitory activities, peptide profiles and organic acid contents in kefir produced by kefir grains plus lactic acid bacteria as adjunct cultures were determined. All the kefir samples showed almost similar peptide profiles as detected by RP-HPLC, but quantitative differences were observed during storage. The ACE-inhibitory activities of different lactic cultures did not exhibit a linear tendency during storage period. After 7 days of storage, there was a significant increase in ACE-inhibitory activity of the sample fermented with Lactobacillus helveticus. However, a kefir sample containing Streptococcus thermophilus, Lactobacillus acidophilus and Bifidobacterium animalis subsp. lactis exhibited a higher ACE-inhibitory activity (92.23%) compared to the other samples.

A mixed commercial starter culture containing Lactococcus lactis subps lactis and Lactococcus lactis subsp cremoris (Cheese A, control) was combined with three adjunct cultures including Lactobacillus casei (Cheese B), Lactobacillus plantarum (Cheese C) and Lactobacillus bulgaricus (Cheese D) in the manufacture of white brined cheese using goat's milk. Use of adjunct culture was not significantly affected pH and gross chemical composition except for nitrogenous compounds; however, use of adjunct cultures in cheese manufacture showed a potential increase in ACE-inhibitory and antioxidant activity parallel to the increase in water-soluble nitrogenous compounds until the 60th day of ripening. The highest antioxidant and ACE-inhibitory activity was detected in cheese D (62.55%) and cheese B (51.95%), respectively. All cheese samples showed almost similar peptide profile; however, quantitative differences were observed. In conclusion, use of adjunct cultures in white-brined goat-milk cheese manufacturing contribute to increase in ACE-inhibitory activity and antioxidant activity.

PubMedID: 26119429 Iranian White cheese was manufactured from ultrafiltered cows' milk using different concentrations of salt consisting of 1, 2·5, 4% and salt free. Chemical composition, proteolysis, counts for lactic acid bacteria and sensory evaluation were examined during 90 d of ripening. It was found that the use of different salt concentrations significantly influenced all chemical composition, proteolysis, total number of lactic acid bacteria and sensory characteristics of the cheeses. Increasing the salt concentrations caused a proportional decrease in proteolysis determined by both urea-PAGE of caseins and RP-HPLC of peptides. With increased salt concentration, total number of lactic acid bacteria decreased. Cheeses with 1 and 2·5% salt were suitable and acceptable in odour and flavour that may be due to the proportional level of proteolysis products. In conclusion, reducing salt concentration from 4 to 2·5 and 1% had no ineligible effect on the quality and acceptability of the cheese. © 2015 Proprietors of Journal of Dairy Research.

The effects of ripening temperature and adjunct cultures (Lactobacillus helveticus and Lactobacillus casei) on the volatile compounds and sensory and textural properties of white-brined cheese were investigated. Three batches of cheese were produced: cheese A was inoculated with only cheese starter culture (Lactococcus lactis subsp. lactis plus Lactococcus lactis subsp. cremoris), cheese B was inoculated with cheese starter culture plus Lactobacillus helveticus and cheese C was inoculated with cheese starter culture plus Lactobacillus casei. Cheeses were ripened at 6 or 12 °C and analyzed at 30-day intervals up to 120 days of ripening. The use of adjunct culture and ripening temperature significantly influenced the pH and proteolysis of cheeses (P < 0.05). Acids, ketones and alcohols were found at high levels in all three cheeses. Volatiles were significantly influenced by the use of the adjunct cultures, ageing and to some extent ripening temperature (P < 0.05). Textural parameters of the cheeses were significantly affected by the adjunct culture during ripening (P < 0.05). The sensory scores of the cheese samples decreased during the ripening period. An age-related bitterness was detected by the panellists in 90 or 120-day-old cheeses with added adjunct cultures. In conclusion, the use of adjunct culture and ripening at 12 °C enhanced the volatile composition and changed the texture profiles of the cheeses.

Four different types of mould-ripened Civil cheese were manufactured. A defined (nontoxigenic) strain of a Penicillium roqueforti (SC 509) was used as the secondary starter with and without addition of the whey cheese (Lor); in parallel, secondary starter-free counterparts were manufactured. Chemical composition, microbiology and proteolysis were studied during the ripening. The incorporation of whey cheese in the manufacture of mould-ripened Civil cheese altered the gross composition and adversely affected proteolysis in the cheeses. The inoculated P. roqueforti moulds appeared to grow slowly on those cheeses, and little proteolysis was evident in all cheese treatments during the first 90 days of ripening. However, sharp increases in the soluble nitrogen fractions were observed in all cheeses after 90 days. Microbiological analysis showed that the microbial counts in the cheeses were at high levels at the beginning of ripening, while their counts decreased approximately 1–2 log cfu/g towards the end of ripening.

The objective of the study was to determine the effects of exopolysaccharide (EPS)-producing or non-EPS-producing starters on proteolysis, physical and microstructural characteristics of full-fat or low-fat Tulum cheeses during ripening. For this purpose, Tulum cheese was manufactured using full- or low-fat milk with EPS-producing and non-EPS-producing starter cultures. Chemical composition, proteolysis, texture profiles and microstructure of the cheeses were studied during 90 days of ripening. Urea-PAGE of water-insoluble and RP-HPLC peptide profiles of water-soluble fractions of the cheeses showed that the use of starters resulted in different degradation patterns in all cheeses during ripening. Although ß-casein exhibited similar degradation patterns in all cheeses, small differences are present in ?s1-casein degradation during ripening. Reducing fat in Tulum cheese changed the RP-HPLC peptide profile of the cheeses. The use of EPS-producing cultures improved the textural characteristics and changed the microstructure and proteolysis of low-fat Tulum cheese. © 2013 Institute of Food Science and Technology.

Free fatty acids profiles of 11 different cheese varieties sold in Turkey were determined to assess the development of lipolysis. Results obtained showed that the concentrations of short chain fatty acids (C4 and C6 free fatty acids) were close in all cheeses (P > 0.05), except for Canak cheese. However, significant differences were noted among the samples for other free fatty acids including C8 to C18:2 (P < 0.05). Palmitic (C16) and oleic (C18:1) acids were the most abundant free fatty acids in all cheese samples. Principal component analysis was applied to simplify interpretation of the data and distinguish the variety of the cheeses on the plot. Canak cheese gave a dramatically different free fatty acid profile from the other cheeses, probably because of the fact that ripening of this variety is achieved in the earthenware pots for about 1 year. Van Otlu (ripened with special herbs) and Civil (ripened by spontaneously molding on its surface) cheeses differed from the others by ANOVA and principal comp...

Milk from two different breeds (Gokceada and Turkish Saanen) and three different starter culture systems (starter-free, mesophilic and thermophilic cultures) were used in the manufacture of Gokceada goat cheeses. Milk from the two breeds differed in dry matter, protein, fat and ash contents. These differences were reflected on the yield and chemical composition of the cheese. The pH values and soluble nitrogen fractions (in water, 12% trichloroacetic acid, and 5% phosphotungstic acid) were significantly influenced by the starter culture systems, but not the types of milk. The degradation of αs-caseins and its degradation products sharply increased after 60 days of ripening, especially in the cheese made using mesophilic starters. Greater changes were observed in RP-HPLC peptide profiles of the cheeses made using mesophilic starter cultures during ripening; however, the breed has minor effect on peptide profile. In conclusions, cheeses made using mesophilic starter culture exhibited different proteolysis patterns during ripening and the milk from Gokceada breed increased the gross composition parameters and cheese yield.

Due to practical and hygienic uses in storage and marketing, cheese maker preference for the use of vacuum packaging instead of the brining method has increased significantly in recent years. The objective of the paper was to study and compare the chemistry, biochemistry, and microstructure of Mihalic cheeses ripened in vacuum packaging or under brine over 360 days. Proteolysis in Mihalic cheese was quite low (e.g., pH 4.6 soluble nitrogen was lower than 15%, as a percentage of the total nitrogen, and αs1-casein was slower in comparison to other brined cheeses) due to its high salt-in-moisture and low moisture contents. Urea-PAGE patterns of the pH 4.6 insoluble fractions of the cheeses showed different degradation patterns of αs1-casein in cheeses of different ages. However, β-casein was relatively resistant to hydrolysis. Packaging the cheese in polyethylene bags significantly increased the levels of pH 4.6 soluble nitrogen, 12% trichloroacetic acid-soluble nitrogen, and free amino acids compared to the cheeses ripened in brine. The total concentrations of free amino acids (FAA) in cheeses increased after 120 days of ripening, and Glu, Val, Leu, Lys, and Phe were the most abundant FAA in the cheeses. Higher levels of these AAs were found in the cheeses ripened in polyethylene bags. The peptide profiles by reversed-phase high-performance liquid chromatography of 70% (v/v) ethanol-soluble and ethanol-insoluble fractions of the pH 4.6 soluble fraction of the cheeses revealed that slight differences were found in the levels of some peptides between cheeses. Majority of the volatile compounds were present at higher concentrations in vacuum-packaged cheeses than in those ripened in brines. The images obtained by scanning electron microscopy of the cheeses ripened in polyethylene bags were clearly different (the protein matrix was more compact) from those of brine-ripened cheeses. The cheese ripened in vacuum packaging was completely different in terms of chemical composition, proteolysis, volatile composition, and microstructure. It was concluded that the vacuum packaging may be useful to maintain the chemical and biochemical qualities of Mihalic cheese, and it is also an easy practice during ripening.

a b s t r a c t In Turkey and the near countries in Middle East and Balkans many cheeses and fermented milk products are manufactured with milk from small ruminants. Some of these products are called with different names and have modified manufacturing procedures, but all of them are important for the consumers due to the type of milk used. Products made with goat's or sheep's milk have some different and interesting characteristics especially, taste, aroma, appearance and chemical constituents, compared to the counterparts made with cow's milk. In Turkey, although some cheeses and fermented milk products were origi- nally produced using milk only from small ruminants, nowadays cow's milk is mixed with this milk due to the limited production of the first. The significant decrease in the pro- duction of goats or sheep is probably due to migration of population from rural area to urban, non-cooperating in farms, low yields in production and milking, unproductive pas- tures, increasing prices in feeds and labor and some problems for agricultural policies and managements. However, the consumers' demands for dairy products of high nutritional and health value, has increased the popularity of dairy products from small ruminants. This paper discusses the characteristics and technology procedures of some dairy products made using small ruminants' milk including different types of cheese and yogurt, butter, ice cream, ayran, kefir and drinking milk. Also, a short statistical data on goat and sheep production and the utilization status of their milk products are discussed.

The effect of pasteurization of cheese milk and cooking temperature of the curd on proteolysis of Malatya cheese was examined during ripening. The cheeses that were characterized by the scalding of curd in hot whey were manufactured from raw or pasteurized milk and the curds were scalded in hot whey at 60, 70, 80 or 90 °C. Differences in the levels of pH 4.6-soluble nitrogen between cheeses were significant (P < 0.05) after 30 days of ripening. Urea-polyacryl-amide gel electrophoresis of the pH 4.6-insoluble fractions showed that both αs1- and β-caseins were not extensively degraded, especially after 30 days of ripening, but β-casein was less degraded than αs1-casein. Analysis of peptide profiles of the pH 4.6-soluble fractions by RP-HPLC showed significant differences in the concentrations of some peptides between the cheeses. Principal component analysis distinguished the cheeses made from raw or pasteurized milk based on their peptide profiles. The results suggest that the pasteurization of cheese milk had a greater effect on peptide profiles of cheese than scalding temperature of the curd.

In this study, a possible use of ß-glucan hydrocolloidal composite as a fat replacer in the manufacture of non-fat yogurts was investigated. The yogurts with added ß-glucan composite were compared with non-fat yogurt without addition of ß-glucan composite and the samples were analysed for physical, chemical and sensory attributes after 1, 7 or 15 d of storage. Fat and protein contents of the experimental yogurts were identical, while ash content differed. Addition of ß-glucan composite did not show a significant change of pH, titratable acidity, acetaldehyde, volatile fatty acids and tyrosine contents at any storage time. Titratable acidity and tyrosine content increased significantly throughout storage. Gel firmness and water-holding capacity in the yogurts were not influenced by addition of ß-glucan composite, but these variables decreased with storage time. Addition of ß-glucan composite and storage time caused a decrease in whey separation. Viscosity values in the yogurts increased by addition of ß-glucan composite and storage time. Sensory results indicated a preference for control yogurts; however, use of low levels of ß-glucan composite in the production of non-fat yogurt gave satisfactory sensory scores. Yogurts containing 0.25% or 0.50% ß-glucan hydrocolloidal composite were acceptable by expert panels and had scores similar to the control yogurt. © 2007 Elsevier Ltd. All rights reserved. Firat University Scientific Research Projects Management Unit This work was supported by a grant from the Cukurova University Academic Research Projects Unit (Project No. ZF.2005. BAP.16). The authors wish to thank Professor G.E. Inglett and Dr. G. Konuklar (Cereal Products & Food Science Research Unit, NCAUR, ARS, USDA, Peoria, IL, USA) for supplying ß -glucan hydrocolloidal composite used in the manufacture of low-fat yogurt.

Summary The performance and relative contribution of four single strains of lactococci (UC317, NCDO763, HP or SK11) as starters for cheese-making and ripening properties of Beyaz cheeses were compared. Gross composition, secondary proteolysis (water-soluble, 12% trichloroacetic acid-soluble, 5% phosphotungstic acid-soluble nitrogen fractions and total free amino acid contents), lipolysis (acid degree values, ADV) and cheese grading were monitored during 90 days of ripening. Chemical composition of whey samples obtained during cheese-making were found to be quite similar; however, whey samples obtained from NCDO763 or HP cheeses had the highest and the lowest pH values, respectively (P 0.05). The highest concentrations of soluble nitrogen and total free amino acid contents were observed in the cheeses made with NCDO763. The cheeses made with different strains of lactococci showed marked differences in cheese proteolysis during ripening.

The objective of the present study was to investigate the influence of container material (plastic or goat-skin bag) on the growth of lactic acid bacteria in Tulum cheese during 9 months of ripening. The lactic acid bacteria in Tulum cheeses were periodically counted on MRS and M17 agars throughout ripening. Results showed that the highest counts of lactic acid bacteria on MRS or M17 were observed at the beginning of ripening and their counts decreased during later stages of ripening. The cheese samples ripened in plastic bags exhibited higher numbers of LAB on MRS and M-17 agars than those ripened in goat-skin bags. A total of 112 strains of lactic acid bacteria were isolated from Tulum cheeses ripened in plastic or goat-skin bags during ripening. The lactic acid bacteria present in the cheese were classified by Microbial Identification System (MIS) based on a comparison of the fatty acid methyl ester profiles. Different species including Enteroccocus, Lactobacillus, Streptococcus, Lactococcus and Pediococcus genera were found in unripened cheese. As ripening proceeded, the species Streptococcus and Lactococcus disappeared and the percentages of the species Enterococcus was unchanged in both containers. There were slight differences between the cheeses ripened in plastic or goat-skin bags in terms of the profiles of lactic acid bacteria isolated. Some species including L. brevis, L. mesenteroides subsp. dextranicum, P. damnosus and E. mundtii were isolated only in the cheeses ripened in plastic bags; however, L. coryniformis and L. malafermentans were isolated only in the cheeses ripened in goat-skin bags at 6 or 9 months of ripening. Also the numbers of E. faecalis isolates were higher in the cheeses ripened in plastic containers than cheeses ripened goat-skin bags at the 6 or 9 months of ripening. The results showed that Lactobacillus and Enterococcus were the predominant species in matured Tulum cheeses in both ripening containers. It seemed possible to produce Tulum cheese with similar characteristics from both the containers used.

Mould-ripened civil is a traditional cheese produced mainly in eastern Turkey. The cheese is produced with a mixture of civil and whey curd cheeses (lor). This mixture is pressed into goat skins or plastic bags and is ripened for more than three months. Naturally occurring moulds grow on the surface and inside of the cheese during ripening. In this research, 140 Penicillium roqueforti strains were isolated from 41 samples of mould-ripened civil cheese collected from Erzurum and around towns in eastern Turkey. All strains were capable of mycotoxin production and were analysed using an HPLC method. It was established that all the strains (albeit at very low levels) produced roquefortine C, penicillic acid, mycophenolic acid and patulin. The amounts of toxins were in the ranges 0.4-47.0, 0.2-43.6, 0.1-23.1 and 0.1-2.3 mg kg(-1), respectively. Patulin levels of the samples were lower than the others. The lowest level and highest total mycotoxin levels were determined as 1.2 and 70.1 mg kg(-1) respectively. The results of this preliminary study may help in the choice of secondary cultures for mould-ripened civil cheese and other mould-ripened cheeses.

PubMedID: 16162519 Turkish White-brined cheese was manufactured using Lactococcus strains (Lactococcus lactis ssp. lactis NCDO763 plus L. lactis ssp. cremoris SK11 and L. lactis ssp. lactis UC317 plus L. lactis ssp. cremoris HP) or without a starter culture, and ripened for 90 d. It was found that the use of starters significantly influenced the physical, chemical, biochemical, and sensory properties of the cheeses. Chemical composition, pH, and sensory properties of cheeses made with starter were not affected by the different starter bacteria. The levels of soluble nitrogen fractions and urea-PAGE of the pH 4.6-insoluble fractions were found to be significantly different at various stages of ripening. Urea-PAGE patterns of the pH 4.6-insoluble fractions of the cheeses showed that considerable degradation of ?s1-casein occurred and that ß-casein was more resistant to hydrolysis. The use of a starter culture significantly influenced the levels of 12% trichloroacetic acid-soluble nitrogen, 5% phosphotungstic acid-soluble nitrogen, free amino acids, total free fatty acids, and the peptide profiles (reverse phase-HPLC) of 70% (vol/vol) ethanol-soluble and insoluble fractions of the pH 4.6-soluble fraction of the cheeses. The levels of peptides in the cheeses increased during the ripening period. Principal component and hierarchical cluster analyses of electrophoretic and chromatographic results indicated that the cheeses were significantly different in terms of their peptide profiles and they were grouped based on the use and type of starter and stage of ripening. Levels of free amino acid in the cheeses differed; Leu, Glu, Phe, Lys, and Val were the most abundant amino acids. Nitrogen fractions, total free amino acids, total free fatty acids, and the levels of peptides resolved by reverse phase-HPLC increased during ripening. No significant differences were found between the sensory properties of cheeses made using a starter, but the cheese made without starter received lower scores than the cheeses made using a starter. It was found that the cheese made with strains NCDO763 plus SK11 had the best quality during ripening. It was concluded that the use of different starter bacteria caused significant differences in the quality of the cheese, and that each starter culture contributed to proteolysis to a different degree. © American Dairy Science Association, 2005. This research was funded in part by Scientific Research Project Units of Cukurova University (Adana, Turkey) .

Turkish White cheese is a brined (or a pickled) cheese variety with a soft or semi-hard texture and a salty, acid taste. Some aspects of this cheese are reviewed: e.g., milk supply, use of starters and enzymes, manufacturing technology, chemical composition and microflora, chemical and biochemical changes during ripening in brine. Several characteristics of Turkish White cheese are compared to other White brined cheese varieties such as Feta and Domiati. The findings of this review suggest that future research on Turkish White cheese should characterise the changes in microflora, biochemistry and texture during ripening. Previous studies tended to focus on the chemical composition of Turkish White cheese, and little attention was directed towards the detailed characterisation of nitrogen fractions, flavour compounds, rheological and microbiological properties and their effects on the quality of the end-product.

The effects of use of adjunct cultures (Lactobacillus helveticusandLb. casei) and ripening temperatures (6 or 12 °C) on proteolysis and angiotensin-I converting enzyme (ACE)-inhibitory activity in white-brined cheeses were investigated during 120 d ripening. Proteolysis was monitored by urea-polyacrylamide gel electrophoresis (urea-PAGE) and reversed phase-HPLC (RP-HPLC) of water-insoluble and -soluble fractions of the cheeses, respectively. Urea-PAGE patterns of the samples revealed that the intensities of the bands representing casein fractions decreased in the experimental cheeses, being more pronounced in the cheeses made with adjunct cultures. Similarly, peptide profiles and the concentrations of individual and total free amino acids were influenced by both the adjunct cultures and ripening temperatures. The ACE-inhibitory activity of the water-soluble extracts of the cheeses were higher in the cheeses made using adjunct cultures (especiallyLb. helveticus) and ripened at 12 °C. The ACE-inhibitory activity did not decrease during ripening. The contribution ofLb. helveticusto the development of proteolysis and ACE-inhibitory peptide activities were higher than that ofLb. casei. To conclude, the use ofLb. helveticusas adjunct culture in white-brined cheese and ripening at 12 °C would be recommended to obtain white-brined cheese with high ACE-I-inhibitory peptides activity and higher levels of preoteolysis.

Many consumers are interested in the relationship between food quality and nutritional value when choosing to buy food. Dairy foods include a wide variety of foods such as liquid milk, fermented milks, cheese, cream, butter, and ice cream. Consuming milk and dairy products improves the overall nutritional quality of the diet. The chemical composition of dairy foods influences their nutritive value. Dairy foods provide substantial amounts of essential nutrients including fat, protein, lactose, calcium, potassium, phosphorus, magnesium, some vitamins (e.g., A, B1, B2, B12, and D), bioactive peptides, and lipids. Nutritional quality assessment is the key for protecting the high nutritional value of milk from farm to marketplace. This chapter deals with evaluating modifications and changes in nutritional components of milk and milk products in the course of processing, including recent processing techniques for minimal nutrient losses. © 2014, Springer Science+Business Media New York.

Moldy Civil is a mold-ripened variety of cheese produced mainly in eastern Turkey. This cheese is produced with Civil cheese and whey curd cheese (Lor). Civil cheese has had a geographical presence since 2009 and is manufactured with skim milk. In the production of Moldy Civil cheese, Civil cheese or a mixture of Civil and Lor cheese is pressed into goat skins or plastic bags and ripened for 3 months or longer. During the ripening period, natural contaminating molds grow on the surface of and inside the cheese. In this study, 186 mold strains were isolated from 41 samples of Moldy Civil cheese, and 165 of these strains were identified as Penicillium roqueforti. Identification and mycotoxicologic analyses were conducted using morphotypic and molecular methods. PCR amplicons of the ITS1-5.8S-ITS4 region were subjected to sequence analysis. This research is the first using molecular methods on Moldy Civil cheese. Mycotoxicologic analyses were conducted using thin-layer chromatography, and random amplified polymorphic DNA genotypes were determined using the ari1 primer. Of 165 isolates, only 28 produced no penicillic acid, P. roqueforti toxin, or roquefortine.

The C18 unsaturated fatty acid (UFA) selectivity of three immobilized lipases, namely, Lipozyme TL IM from Thermomyces lanuginosa, Lipozyme RM IM from Rhizomucor miehei, and Novozym 435 from Candida antarctica, was determined in acidolysis conducted in hexane. Tripalmitin with a mixture of equimolar quantities of C18 UFAs was used as the substrate. Significantly different incorporation rates were observed for C18 UFAs used (p < 0.05). The highest incorporation was obtained for all three C18 UFAs with Novozym 435 followed by Lipozyme RM IM and Lipozyme TL IM catalyzed acidolysis under default conditions (substrate mole ratio 1:1; temperature 50 A degrees C; reaction time 6 h; enzyme dosage 10%). Incorporation of the equimolar quantities of C18 UFAs was in the order C18:3 > C18:2 > C18:1 which also reflects C18 UFAs preferences of the lipases. The effects of operating variables on incorporation or UFA selectivity of lipases were also investigated. Among the experimental parameters including the mole ratio of fatty acid to triolein, temperature, enzyme dosage, and time on incorporation, the effect of the substrate mole ratio on UFA selectivity was greater than those of the others.

In this study, the influence of rennet concentration on chemical composition, proteolysis and sensory properties of Halloumi cheese was evaluated during ripening. Halloumi cheese was manufactured from raw cow's milk using four levels of rennet (0.2, 0.25, 0.3 or 0.4 g rennet/kg cheese milk) and was ripened for 60 days at 4C. Proteolysis in the cheese was measured by determining soluble nitrogen fractions both in water and in 12% trichloroacetic acid as well as by patterns of urea–polyacrylamide gel electrophoresis. Cheese grading was performed by an expert panel throughout the ripening period. The chemical composition of the cheese was significantly influenced by the level of rennet, which could be related to the differences in moisture contents of the cheese. The levels of water- or 12% trichloroacetic acid-soluble nitrogen fractions and degradations of αs1- or β-caseins were quite low during the cheese maturation. No relation was found between rennet concentrations and casein degradation in the cheese during ripening. Results indicated that the different concentrations of rennet did not significantly influence the proteolytic profiles and sensory scores of Halloumi cheese; that is, an amount of rennet between 0.2 and 0.4 g rennet/kg cheese milk resulted in a similar quality of Halloumi cheese. PRACTICAL APPLICATIONS Halloumi cheese was manufactured from raw cow's milk using different concentrations of rennet and was ripened for 60 days. The chemical composition of the cheese was influenced by different concentrations of rennet; however, ripening indices (proteolysis) and sensory attributes were identical in all samples. It is concluded that different concentrations of rennet (0.2–0.4 g rennet/kg cheese milk) have no significant influence on the ripening characteristics of Halloumi.

Tulum cheeses were manufactured from raw ewe's milk and ripened in goat's skin bags (tulums) or plastic containers to understand the effect of ripening container on the chemical composition, biochemistry, microbiology, and volatile composition of Tulum cheeses during 150 d of ripening. Chemical compositions of the cheeses ripened in tulums were significantly different and the moisture contents decreased rapidly in those cheeses because of the porous structure of the tulum. Higher microbial counts were detected in the cheeses ripened in plastic than in cheeses ripened in tulums. Differences in nitrogenous compounds and total free AA of the cheeses were not significant. Total concentrations of free AA in cheeses increased with age and Glu, Ala, Val, Leu, and Phe were the most abundant AA in the cheeses. Urea-PAGE of pH 4.6-insoluble fractions of the cheeses during ripening showed similar degradation patterns in all cheeses. Peptide profiles by reversed-phase HPLC of pH 4.6- and ethanol-soluble or ethanol-insoluble fractions of the cheeses revealed only minor differences in the concentrations of some peptides among the cheeses; however, age-related changes in peptide concentrations were significantly different among the cheeses. Cheeses were analyzed at 90 d of ripening for volatile compounds by solid-phase microextraction gas chromatography-mass spectrometry. One hundred volatile components were identified, including 11 acids, 16 esters, 12 methyl ketones, 7 aldehydes, 22 alcohols, 7 sulfur compounds, 6 terpenes, and 19 miscellaneous compounds. The main components were short-chain fatty acids, 2-butanone, diacetyl, and primary alcohols. Quantitative differences in several volatile compounds were evident among the cheeses. Cheeses ripened in tulums or plastic had similar aroma patterns, but the concentrations of some components were different.

The chemical and microbial qualities, including fungal flora, of 30 samples of Kuflu cheese randomly purchased from different markets in Turkey were investigated. The gross composition of the cheese samples ranged between 37.65-53.65% moisture, 6.21-40.09% fat-in-dry matter, 4.70-10.07% salt-in-moisture and 26.18-44.85% protein. The mean pH value of the cheeses was 6.29+/-0.28 and pH values ranged from 5.52 to 7.22. Variations between the samples in terms of their gross composition suggested a lack of quality standards in cheesemilk, cheesemaking procedure and ripening conditions. The levels of main microbial groups including total mesophilic and coliform bacteria, yeasts and moulds and the presence of some potentially pathogenic microorganisms (E. coli, Salmonella spp. and Staphylococcus aureus) were determined. The high numbers of all microbial groups and presence of potentially pathogenic organisms in the cheese samples suggested that the production and maturation of Kuflu cheese should be improved by better hygiene. Moulds at the cheese surface were isolated and identified. A total of 24 different mould species were detected and the genus most frequently isolated was Penicillium spp. which represented 70.25% of total isolates. Penicillium commune, P. roqueforti and P. verrucosum were the most abundant species in the cheeses sampled. The other dominant fungal groups were Geotrichum candidum, Penicillium expansum and P. chrysogenum. Other genera isolated from the cheese were Acremonium, Alternaria, Aspergillus, Cladosporium, Geotrichum, Mucor, Rhizopus and Trichoderma. The potentially toxigenic species, including some Penicillum spp. and Aspergillus flavus, were also detected.

The influence of different levels of inulin on the quality of fat-free yogurt production was investigated. Inulin was added to milk containing 0.1% of milk fat to give inulin levels of 1, 2 and 3%. The experimental yogurts were compared with control yogurt produced from whole milk. The total solids content of milk was standardized to 14% by adding skim milk powder to the experimental yogurt. The chemical composition, pH, titratable acidity, whey separation, consistency, acetaldehyde and volatile fatty acidity contents were determined in the experimental yogurts after 1, 7 and 15 days. Sensory properties of the yogurts were evaluated during storage. The addition of inulin at more than 1% increased whey separation and consistency. Acetaldehyde, pH and titratable acidity were not influenced by addition of inulin. Tyrosine and volatile fatty acidity levels were negatively affected by inulin addition. With respect to the organoleptic quality of yogurt, inulin addition caused a decrease in organoleptic scores: the control yogurt had the highest score, and the lowest score was obtained in yogurt samples containing 3% of inulin. Overall, the yogurt containing 1% of inulin was similar in quality characteristics to control yogurt made with whole milk. © 2005 Society of Dairy Technology.