Lactic acid bacteria are important in fermented meat, dairy, vegetable, fruit and cereal industry for their starter and
probiotic properties. The market ratio of functional foods produced with probiotic strains of lactic acid bacteria have
been considerably developed in recent years due to demand towards on natural and healthy products of consumers.
Accordingly, 26 isolates previously isolated from different foods and having probiotics characteristics were examined
for their industrial and probiotic properties together with 6 standard type cultures comparatively. Acid production
abilities of relevant isolates were found between 1.07-2.47% and averagely 1.81%, where the pH values were found
between 3.30-4.41 and averagely 3.85. The hydrophobicity values were in between 0 and 50.82%. L. plantarum and
P. pentosaceus isolates were found more tolerant due to their resistance to high salt and bile and for growing in 3.5
and 9.6 pH. All of the isolates showed sufficient resistance to gastric water, alcohol, heavy metals, antibiotics and
H2O2 as well as had antimicrobial activity, β-galactosidase activity and proteolytic activity for to be assigned a starter
culture.
In this study, the effect of oven drying on the physico-chemical properties of dried pears during storage was
determined. The pear of Ankara cultivar was used in experiments. Pears were cut into cubes (9x9x9 mm) or
rectangles (9x12x13 mm). After treated with sodium metabisulfite, pear samples were oven-dried. Moisture, water
activity, colour (Hunter L, a, b value, croma value and hue angle), phenolic composition and aromatic compounds as
physico-chemical properties of dried samples were determined during 0, 1, 3 and 6 months of storage.
In this study, the quality properties of breads which were produced by the addition of different fruit and vegetable
flours (chickpea, soybean, pinto bean, lentil, carob and pea) were determined. In the first part of the study, different
fruit and vegetable flours were added to bread formulation by replacement of wheat flour (20% by weight). Moisture
content, water activity, color values (CIE L*, a* and b*) and dimensions of baked breads were determined. In addition,
color, odor, flavor, porosity and overall acceptance of breads were evaluated by semi-trained panelists. According to
results of sensory evaluation panel, the highest sensory scores were obtained from breads with pinto bean flour. For
this reason, in the second part of the study, the effect of different amounts of pinto bean flour addition (5%, 10%, 15%,
20% and 25%) on the physical and quality properties of breads were studied. As a result, the highest sensory scores
were obtained from breads containing 10% pinto bean flour.
Key Words:Bread, Fruit and vegetable flour, Pinto bean flour, Quality properties, Sensory evaluation
5
Beyaz Peynirde Nisini Tolere Eden Laktik Asit Bakteri Miktarı ve Çeşitliliği
Amount and Diversity of Lactic Acid Bacteria Tolerating Nisin at White-brined Cheese
Pages 36-40
Ömer Şimşek , Burcu Kördikanlıoğlu, Gizem Yazıcı, Halil İbrahim Kaya
The aim of this study is the isolation of LAB tolerating nisin and identification within 16S rDNA sequencing ultimately.
The microbiological quality of cheeses obtained from various Denizli local bazaars were found lower than the samples
packaged and sold with commercial brands. The LAB counts grown in M17 and MRS were 8.38 and 7.29 log cfu/g,
respectively. When 500 IU/mL nisin was inoculated to the M17 and MRS, the LAB counts in cheese samples were
averagely 4.99 and 2.92 log cfu/g respectively. The 23 collected LAB tolerating nisin was found 97% similar within;
Lactobacillus plantarum (4), Lactobacillus casei (3), Lactobacillus paracasei (3), Enterococcus faceium (3),
Lactobacillus rhamnosus (2) and Lactobacillus fermentum (2). In conclusion, lactic cultures existed in white-brined
cheese flora was affected from nisin significantly and potential lactic cultures which would be useful for the production
of White-brined cheese production together with nisin were collected and identified.
Liposomes are polar lipid bilayers vesicles used in pharmaceutical applications for years. These spherical vesicles are
manufactured from natural phospholipid compositions known as lecithins. Their utilization in foods have recently
attracted some interest. Using liposomes as encapsulating agents in foods provides a number of advantages like
increased stability for the active agent and minimized interaction of capsuled material with the surrounding medium.
However, what sets liposomes apart from other encapsulation agents is the ease of capsulation and its natural
composition. Nevertheless, the fragile nature of liposomes poses some challenges with their use under extremes of
temperature, pH or pressure. Studies have shown that a number of methods could help to increase liposomes’
stability. This review is written with the purpose of providing food scientists, who plan to use liposomes as an
encapsulation agent, with a Turkish source covering the chemical and physical structure of liposomes, the advantages
they provide, production and characterization methods, stability issues, and their use in food related applications.
Pectin methylesterase (PME), polygalacturonase (PG) and lipoxygenase (LOX) are the most important enzymes in
tomatoes (Solanum lycopersicum) and in tomato processing. PME is generally chosen as an indicator enzyme for
thermal processing due to its highest thermal stability. Pectolytic enzymes have great impact on texture, viscosity,
color stability, clarity and efficiency of the product. LOX activity catalyses the essential fatty acids oxidation which
causes off-flavor compounds in tomato and tomato products. Hence, enzyme properties in tomatoes and effects of
enzymes on quality of tomato products will be summarized, in addition effect of thermal and non thermal processing
on enzyme inactivation will be overviewed.
During the processing of raw milk, characteristics of microbial population affect significantly shelf life, organoleptic
quality and yields of raw milk. At the present time cold storage before processing of raw milk is a common treatment
and this case improves psychrotrophic bacterial growth. Therefore, their count in cold milk may become more than
their ideal limit of 10 % of the initial raw milk microbial population. Psychrotrophic bacteria are able to form
extracellular or intracellular termoresistant enzymes that cause spoilage of milk and dairy products. Also, some
species of psychrotrophic bacteria resist to antibiotics and/or produce toxins. Today psychrotrophic bacteria cause
problems of spoilage and significant economic losses. In this review, the effect of psychrotrophic bacteria on the
quality of raw milk and dairy products is presented.
Nowadays demands for high quality foods especially meat that are fresh tasting and nutritious have created
considerable interest in the development of new preservation technologies. Although traditional methods used in
preservation of meat have helped to ensure a high level of food safety and prolonged the shelf life of foods, some
techniques like heat treatment may cause quality loss in product and excessive energy consumption. Since these
techniques may lead undesirable effects on meat quality, considerable effort has been made on using new
preservation techniques combined with traditional methods or an alternative to traditional methods. High pressure
processing (HPP), ohmic heating, dielectric heating, high intensity pulsed light, X-rays and electron beams have taken
part between these further preservation techniques implemented in meat industry. These techniques have enabled
the nutrient ingredient, functional and sensory properties of foods to protect, healthy and long shelf life having food to
produce in meat industry. Especially, they have contributed to the development of textural properties of meat due to
changes of protein structure. In addition they are effective in microbial inactivation while no significant degradation of
vitamins, mineral salts, taste, colour and appearance occurs. It has been predicted that these advanced techniques
may replace current counterparts.
Key Words:Preservation techniques, Meat, Quality, Shelf life