Oya Berkay Karaca

Influence of fat replacers on chemical composition, proteolysis, texture profiles, meltability and sensory properties of low-fat Kashar cheese

Changes in chemical composition, proteolysis, lipolysis, texture, melting and sensory properties of low-fat Kashar cheese made with three different fat replacers (Simplesse D-100, Avicel Plus CM 2159 or beta-glucan) were investigated throughout ripening. The low-fat cheeses made with fat replacers were compared with full- and low-fat counterparts as controls. Reduction of fat caused increases in moisture and protein contents and decreases in moisture-in-non fat substance and yield values in low-fat cheeses. The use of fat replacers in the manufacture of low-fat Kashar cheese increased water binding capacity and improved overall quality of the cheeses. Use of fat replacer in low-fat cheese making has enhanced cheese proteolysis. All samples underwent lipolysis during ripening and low-fat cheeses with fat replacers had higher level of total free fatty acid than full- or low-fat control cheeses. Texture attributes and meltability significantly increased with addition of fat replacers. Sensory scores showed that the full-fat cheese was awarded best in all stages of ripening and low-fat variant of Kashar cheeses have inferior quality. However, fat replacers except beta-glucan improved the appearance, texture and flavour attributes of low-fat cheeses. When the fat replacers are compared, the low-fat cheese with Avicel Plus CM 2159 was highly acceptable and had sensory attributes closest to full-fat Kashar cheese.

The Current Approaches and Challenges of Biopreservation

Abstract Due to changes in life styles the food market has globalized. In recent years, people demand functional, minimally processed, and prepared products. These products require longer and more complex food chain, because of which the risk of microbiological contamination increased. Consumer demand for higher quality and naturalness of food requires strict government guarantees of food safety. Therefore, new protection technology is continuously being researched. Biopreservation is one of the alternative food preservation technologies that improves product shelf life, hygienic quality, and minimize the impact on sensory and nutritional properties of perishable food products. Lactic acid bacteria (LAB), bacteriophages with antimicrobial properties, and lysozyme with antibiofilm properties are widely used. Bacteriocins are synthesized peptide or proteins. They usually show antimicrobial effects against antagonistic effect of close relative strains to bacteriocin producers. Bacteriophages are virus isolated bacteria. Phages are also active on fresh-cut produce. Lysozyme is a naturally occurring enzyme found in bodily secretions and used extensively as a feed additive in the livestock industry to prevent late blowing in the cheese industry. In this chapter, we will try to explain the current applications of biopreservation which are investigations about the resistance mechanism, new or improved antimicrobial effect, and security.

Effects of Proteolytic and Lipolytic Enzyme Supplementations on Lipolysis and Proteolysis Characteristics of White Cheeses

Effects of proteolytic (Neutrase, Bacillus subtilis-originate, 0.20 (P1) and 0.40 g 100 L−1 (P2)) and lipolytic (Piccantase A, Mucor miehei-originated, 0.05 (L1) and 0.10 g 100 L−1 (L2)) enzyme supplementations to cheese milk on lipolysis and proteolysis characteristics of 90-day ripened cheese samples were investigated in this study. While enzyme supplementation did not have significant effects on titratable acidity, fat and protease-peptone nitrogen ratios of cheese samples, dry matter, salt, protein, water soluble nitrogen, 12% trichloroacetic acid soluble nitrogen ratio (TCA-SN), 5% phosphotungstic acid soluble nitrogen (PTA-SN), casein nitrogen ratios, penetrometer value, total free fatty acids (TFFA) and total free amino acids (TFAA) were significantly influenced by enzyme supplementations. Individual free amino acids (15 of them) were also determined. Free amino acid contents of enzyme-supplemented cheeses were higher than the control cheese and the values increased in all cheese samples with the progress of ripening (p < 0.05). The highest amino acids in all periods of ripening were identified as glutamic acid, lysine, proline and aspartic acid. The major (Ca, P, Na, K, Mg) and minor (Zn, Fe, Cu, Mn) mineral levels of cheeses decreased with the progress of ripening and the effects of enzyme supplementations on these attributes (except for magnesium and manganese) were found to be significant (p < 0.01). As to conclude, enzyme supplementations increased proteolysis and lipolysis and accelerated ripening and thus reduced ripening durations. Especially the enzyme ratios in P1 and L1 cheeses were found to be suitable for reducing the ripening period in White cheese without any adverse effects.

Functional food ingredients and nutraceuticals, milk proteins as nutraceuticals nanoScience and food industry

In today’s world, food materials contribute to the healthy life of consumers. Bioactive compounds exist naturally in certain foods and are nutritionally important, have physiological benefits, and might help to reduce the risk of many diseases, including cardiovascular disease and cancer. Nanotechnology can be applied by two different approaches: one is the top-down approach, whereby small particles are produced through different size reduction (mechanical) processes, and the other approach is the bottom-up approach in which the nanoparticle is produced by the self-assembly of smaller molecules such as lipids and proteins (chemical processes). Nanotechnology can be applied in the production, processing, safety, and packaging of food and contribute to improve the properties of bioactive compounds, such as solubility, delivery properties, prolonged residence time in the gastrointestinal tract, and efficient absorption through cells by reducing particle size. Application of omega 3 and omega 6 fatty acids, beta carotene, probiotics, prebiotics, vitamins, and minerals as bioactive compounds are used in food nanotechnology. Milk proteins have been used in the production of the nanocarrier. This section will describe functional food ingredients and milk proteins as nutraceuticals, and their usage in nanotechnologic applications.