eng Wydawnictwo Uniwersytetu Przyrodniczego w Poznaniu Acta Scientiarum Polonorum Technologia Alimentaria 16440730 2012-06-30 11 2 99 109 article Karolina M. WĂłjciak 1 Zbigniew J. Dolatowski 1 Department of Meat Technology and Food Quality, University of Life Sciences in Lublin Meat and meat products, which form a major part of our diet, are very susceptible to quality changes resulting from oxidative processes. Quality of fermented food products depends on the course of various physicochemical and biochemical processes. Oxidation of meat components in raw ripening products may be the result of enzymatic changes occurring as a result of activity of enzymes originating in tissues and microorganisms, as well as lipid peroxidation by free radicals. Primary and secondary products of lipid oxidation are extremely reactive and react with other components of meat, changing their physical and chemical properties. Oxidised proteins take on a yellowish, red through brown hue. Products of lipid and protein degradation create a specifi c fl avour and aroma ; furthermore, toxic substances (such as biogenic amines or new substances) are formed as a result of interactions between meat components, e.g. protein-lipid or protein-protein combinations, as well as transverse bonds in protein structures. Oxidation of meat components in raw ripening products is a particularly diffi cult process. On the one hand it is essential, since the enzymatic and non-enzymatic lipid oxidation creates fl avour and aroma compounds characteristic for ripening products; on the other hand excessive amounts or transformations of those compounds may cause the fermented meat product to become a risk to health. https://www.food.actapol.net/volume11/issue2/1_2_2012.pdf probiotic meat products antioxidant oxidative stability colour eng Wydawnictwo Uniwersytetu Przyrodniczego w Poznaniu Acta Scientiarum Polonorum Technologia Alimentaria 16440730 2012-06-30 11 2 111 119 article Wojciech Juzwa 1 Katarzyna Czaczyk 1 Department of Biotechnology and Food Microbiology, PoznaĹ„ University of Life Sciences Background. Flow cytometry constitutes an alternative for traditional methods of microorganisms identifi cation and analysis, including methods requiring cultivation step. It enables the detection of pathogens and other microorganisms contaminants without the need to culture microbial cells meaning that the sample (water, waste or food e.g. milk, wine, beer) may be analysed directly. This leads to a signifi cant reduction of time required for analysis allowing monitoring of production processes and immediate reaction in case of contamination or any disruption occurs. Apart from the analysis of raw materials or products on different stages of manufacturing process, the fl ow cytometry seems to constitute an ideal tool for the assessment of microbial contamination on the surface of technological lines. Material and methods. In the present work samples comprising smears from 3 different surfaces of technological lines from fruit and vegetable processing company from Greater Poland were analysed directly with fl ow cytometer. The measured parameters were forward and side scatter of laser light signals allowing the estimation of microbial cell contents in each sample. Results. Flow cytometric analysis of the surface of food industry production lines enable the preliminary evaluation of microbial contamination within few minutes from the moment of sample arrival without the need of sample pretreatment. Conclusions. The presented method of fl ow cytometric initial evaluation of microbial state of food industry technological lines demonstrated its potential for developing a robust, routine method for the rapid and laborsaving detection of microbial contamination in food industry. https://www.food.actapol.net/volume11/issue2/2_2_2012.pdf flow cytometry microorganisms detection microbial contamination cell sorting eng Wydawnictwo Uniwersytetu Przyrodniczego w Poznaniu Acta Scientiarum Polonorum Technologia Alimentaria 16440730 2012-06-30 11 2 121 135 article Mona A.M. Abd El-Gawad 1 Nawal S. Ahmed 1 M.M. El-Abd 2 S. Abd El-Rafee 3 Dairy Science Department, National Research Center in Dokki, Giza El Buhouth St., Dokki, Egypt Dairy Science Department, Cairo University in GizaEgypt Dairy Technology Department, Animal Production Research Institute, GizaNadi El-Seid St., Dokki, Giza, Egypt Background. The name pasta fi lata refers to a unique plasticizing and texturing treatments of the fresh curd in hot water that imparts to the fi nished cheese its characteristic fi brous structure and melting properties. Mozzarella cheese made from standardized homogenized and non-homogenized buffalo milk with 3 and 1.5%fat. The effect of homogenization on rheological, microstructure and sensory evaluation was carried out. Material and methods. Fresh raw buffalo milk and starter cultures of Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus were used. The coagulants were calf rennet powder (HA-LA). Standardized buffalo milk was homogenized at 25 kg/cm2 pressure after heating to 60°C using homogenizer. Milk and cheese were analysed. Microstructure of the cheese samples was investigated either with an application of transmission or scanning electron microscope. Statistical analyses were applied on the obtained data. Results. Soluble nitrogen total volatile free fatty acids, soluble tyrosine and tryptophan increased with using homogenized milk and also, increased with relatively decrease in case of homogenized Mozzarella cheese. Meltability of Mozzarella cheese increased with increasing the fat content and storage period and decrease with homogenization. Mozzarella cheese fi rmness increased with homogenization and also, increased with progressing of storage period. Flavour score, appearance and total score of Mozzarella cheese increased with homogenization and storage period progress, while body and texture score decreased with homogenization and increased with storage period progress. Microstructure of Mozzarella cheese showed the low fat cheese tends to be harder, more crumbly and less smooth than normal. Curd granule junctions were prominent in non-homogenized milk cheese. Conclusion. Homogenization of milk cheese caused changes in the microstructure of the Mozzarella cheese. Microstructure studies of cheese revealed that cheese made from homogenized milk is smoother and has a fi ner texture than non-homogenized but is also, fi rmer and more elastic. https://www.food.actapol.net/volume11/issue2/3_2_2012.pdf Mozzarella cheese homogenization microstructure buffalo milk sensory evaluation eng Wydawnictwo Uniwersytetu Przyrodniczego w Poznaniu Acta Scientiarum Polonorum Technologia Alimentaria 16440730 2012-06-30 11 2 131 148 article Reza Amiri Chayjan 1 Kamran Salari 1 Hossein Barikloo 1 Department of Agricultural Machinery, Faculty of Agriculture, Bu-Ali Sina University Background. Modelling moisture diffusivity of pomegranate cultivars is considered to be a major aspect of the drying process optimization. Its goal is mainly to apply the optimum drying method and conditions in which the fi nal product meets the required standards. Temperature is the major parameter which affects the moisture diffusivity. This parameter is not equal for different cultivars of pomegranate. So modelling of moisture diffusivity is important in designing, optimizing and adjusting the dryer system. Material and methods. This research studied thin layer drying of three cultivars of pomegranate seeds(Alak, Siah and Malas) under fi xed, semi fl uidized and fl uidized bed conditions. Drying process of samples was implemented at 50, 60, 70 and 80°C air temperature levels. Second law of Fick in diffusion was utilized to compute the effective moisture diffusivity (Deff) of the seeds. Linear and artifi cial neural networks (ANNs) also were used to model Deff of seeds. Results. Maximum and minimum values of the Deff were related to malas and alak cultivars, respectively. Three linear models were found to fi t the experimental data with average R2 = 0.9350, 0.9320 and 0.9400 for Alak, Siah and Malas cultivars, respectively. The best results for neural network were related to feed forward neural network with training algorithm of Levenberg-Marquardt was appertained to the topology of 3-4-3-1 and threshold function of LOGSIG. By the use of this structure, R2 = 0.9972 was determined. Conclusion. A direct relationship was found between Deff and thickness of fl eshy section of the seeds. The Siah cultivar has the highest value of Deff. This is due to higher volume of fl eshy section of the siah cultivar. Cultivar type and air velocity have the highest and the least effect on Deff, respectively. https://www.food.actapol.net/volume11/issue2/4_2_2012.pdf fl uidized bed drying moisture diffusivity pomegranate artifi cial neural network eng Wydawnictwo Uniwersytetu Przyrodniczego w Poznaniu Acta Scientiarum Polonorum Technologia Alimentaria 16440730 2012-06-30 11 2 151 165 article Oluwole Steve Ijarotimi 1 Oluremi Olufunke Keshinro 2 Department of Food Science and Technology, The Federal University of Technology Akure, Nigeria Department of Human Nutrition, College of Medicine, University of Ibadan Queen Elizabeth Road, Ibadan, Nigeria Background. The most popular form of utilization of African locust bean (ALB) is in its traditional fermentation food condiment (iru/dawadawa), which adds protein to a protein-poor diet and also as Medicine. In view of the nutritive values of ALB, the present study therefore aimed at investigating the effect of germination and fermentation on the nutritional quality of ALB fl our. Material and methods. The ALB was obtained from a local market in Akure, Nigeria. The seeds were divided into three portions, and treated as raw African locust bean (RALB), germinated African locust bean (GALB) and fermented African locust bean (FALB) respectively. Each of the samples was milled, sieved and analysed for chemical, functional properties and nutritional qualities using standard methods. Results. Some most important results of the chemical analysis were as follows: protein content range between 33.64 ±0.41 – 41.49 ±1.89 g/100 g, while the energy value was between 442.79 ±2.32 – 457.20 ±2.15 kcal. The P/Ca and Na/K ratio of the RALB were higher than other fl our samples respectively. Total essential amino acid was between 29.960-27.514 mg/100 g. Protein effi ciency ratio (PER) was between 1.78-1.87; essential amino acid index 31.43-34.75%; while biological values were 22.56-26.18%. The dominant fatty acid (FA) composition of the samples was linoleic with 33.687%, 31.578% and 28.7% for RALB, GALB and FALB respectively; while the least was lauric acid. The polyunsaturated/saturated FA ratio ranges between 0.589-0.718. The antinutrient concentration of fermented fl our sample was signifi cantly reduced than other food samples. Conclusion. The present study investigated the effect of germination and fermentation on the nutritional quality of ALB fl our. The fi nding showed that fermentation technique signifi cantly reduced antinutrient concentration and also improved the nutrient composition, particularly amino acid profi le of ALB fl our. https://www.food.actapol.net/volume11/issue2/5_2_2012.pdf African locust bean amino acids fatty acids nutritional quality germination and germination eng Wydawnictwo Uniwersytetu Przyrodniczego w Poznaniu Acta Scientiarum Polonorum Technologia Alimentaria 16440730 2012-06-30 11 2 167 174 article Marzanna Hęś 1 Danuta GĂłrecka 1 Krzysztof Dziedzic 1 Department of Food Service and Catering, PoznaĹ„ University of Life Science Background. In the course of production of buckwheat groats by-products are produced, such as bran and hull, which apart from high content of dietary fi ber, may also constitute valuable sources of antioxidants. The aim of these investigations was to determine the antioxidant activity of extracts from by-products produced during processing of buckwheat for groats. Material and method. Analyses were conducted on bran and hull of buckwheat cv. Kora. Extraction was run using acetone, methanol and water at room temperature for 24 h. The level of phenolics was determined spectrophotometrically with the Folin-Ciocalteau reagent, using (+) catechin as a standard. Antioxidant activity of extracts was analysed in relation to linoleic acid, running incubation for 19 h, by scavenging of stable radicals of DPPH (2,2-diphenyl-1-picrylhydrazyl) and on the basis of metal chelating ability. Recorded results were compared with the activity of BHT (butylated hydroxytoluene). Results. The highest content of polyphenols was found in the methanol extract of hull (168.5 mg/g d.m.), which was also characterised by the best antiradical properties. The lowest content of total phenols was found for water extracts of bran after grinding and fi nal bran, at 20.3 mg/g d.m. and 10.2 mg/g d.m. In the emulsion system the highest activity was found for methanol extracts of hull and bran after grinding (Wo = 0.89), as well as the extract of fi nal bran (Wo = 0.85). A higher chelating ability in relation to Fe (II) ions was observed for bran extracts (after grinding – 76.1%, fi nal bran – 62.2%) than for hull extracts (26%). Conclusions. Extracts obtained from by-products of buckwheat were characterised by high antioxidant activity in the applied model systems. https://www.food.actapol.net/volume11/issue2/6_2_2012.pdf buckwheat hull bran polyphenols antioxidant activity eng Wydawnictwo Uniwersytetu Przyrodniczego w Poznaniu Acta Scientiarum Polonorum Technologia Alimentaria 16440730 2012-06-30 11 2 175 181 article PrzemysĹ‚aw Kowalczewski 1 Konrad Celka 1 Wojciech BiaĹ‚as 1 GraĹźyna Lewandowicz 1 Department of Biotechnology and Food Microbiology, PoznaĹ„ University of Life Sciences Background. The interest in potato juice as a therapeutic agent goes back to the 19th century but its application was not supported by any knowledge about biological activity of this raw material. Factors restricting the medical application of potato juice include its inattractive sensory and functional properties. The aim of the presented investigations was preliminary evaluation of the biological activity of potato juice and the impact on it of some technological operations such as: cryoconcentration and hydrolysis in a membrane reactor. Material and methods. Experiments comprised investigations of antioxidative potentials of fresh potato juice, products of its processing as well as fractions separated because of the size of their molecules using, for this purpose, Folin-Ciocalteu methods and reactions with the ABTS cation radical. Results. The value of the antioxidative potential of fresh potato juice determined by means of the ABTS reagent corresponded to approximately 330 μmol/100 g which is in keeping with literature data. As a result of the cryoconcentration process, the value determined by the Folin-Ciocalteu method was found to increase only slightly whereas the value determined by means of the ABTS reagent almost tripled. The antioxidative potential was found to grow even more strongly in the case of the application of both methods when the process of enzymatic hydrolysis was employed. The total of 5 protein fractions of molecular masses ranging from 11 000 Da to over 600 000 Da, as well as an organic non-protein fraction of the molecular mass of 600 Da, were obtained as a result of the performed separation. All the examined fractions exhibited antioxidative activities. The highest values determined by the Folin-Ciocalteu method were recorded for the protein fraction of 80 000 Da mean molecular mass, while using the ABTS reagent – for the organic, non-protein fraction. Conclusions. Potato juice possesses antioxidative activity which can be enhanced by means of processing, especially, in the course of enzymatic hydrolysis. In addition, it was demonstrated that the organic nonprotein fraction of 600 Da mean molecular mass was characterised by the highest antioxidative activity. https://www.food.actapol.net/volume11/issue2/7_2_2012.pdf potato juice antioxidant activity enzymatic hydrolysis eng Wydawnictwo Uniwersytetu Przyrodniczego w Poznaniu Acta Scientiarum Polonorum Technologia Alimentaria 16440730 2012-06-30 11 2 183 192 article Carlos Lifschitz 1 Section of Pediatric Gastroenterology, Hepatology and Transplantation, Hospital Italiano The purpose of this review is to present information regarding new effects for certain nutrients other than those traditionally known. Zinc has been found to prevent and reduce the duration of common colds. In developing countries, zinc has been shown to reduce the duration and severity of diarrhea and even decrease relapses. Iron supplementation in iron defi cient children, has been shown to improve several aspects of brain function. In studies where iron was given to the mother, 3 of 5 randomized, controlled trials showed a benefi cial effect of iron supplementation on the Psychomotor Development Index at some time points, whereas 2 did not. The chances for infants supplemented with docosahexaenoic acid in the fi rst year of life of having at least 1 event of allergic manifestation or upper respiratory infection or at least 1 event of wheezing/asthma, wheezing/asthma/atopic dermatitis, any allergy, or an upper respiratory tract infection during the fi rst 3 years of life were signifi cantly lower than in the non supplemented group. Epidemiological studies have established a relationship between low levels of serum vitamin D and reduced lung function in healthy adults and asthma onset and severity in children. There was a trend for an independent association between higher levels of maternal circulating 25(OH)D3 levels in pregnancy and decreased odds of lower respiratory tract infections in offspring. https://www.food.actapol.net/volume11/issue2/8_2_2012.pdf minerals zinc iron vitamin D nutrition eng Wydawnictwo Uniwersytetu Przyrodniczego w Poznaniu Acta Scientiarum Polonorum Technologia Alimentaria 16440730 2012-06-30 11 2 193 198 article MirosĹ‚aw Pysz 1 Szymon Polaszczyk 1 Teresa LeszczyĹ„ska 1 Ewa PiÄ…tkowska 1 Department of Human Nutrition, University of Agriculture in Krakow Background. In human nutrition legume seeds are usually subjected to soaking and thermal processes, mainly by using traditional cooking method. This method which has been used for decades, does not allow to control and adjust the parameters of this process. Therefore it does not seem to be the optimal method. Undoubtedly, microwave fi eld is an alternative thermal process to conventional technique. The aim of this study was to assess the impact of microwave fi eld on the activity of trypsin inhibitors and protein quality of three varieties of broad bean seeds. Material and methods. The study was performed on dry seeds of broad bean varieties Windsor White, Bachus and Basta. The seeds were soaked and heated in a microwave. The seeds absorbed different energy doses from 500 J/g, through 750, 1000, 1250, 1500, 1750 to 2000 J/g. The study material prepared in this way was tested for trypsin inhibitor activity, protein solubility and in vitro protein digestibility. The results were analysed by the one-way analysis of variance. Results. Microwave heating resulted in decreased activity of trypsin inhibitors and protein solubility and increased digestibility of protein in all tested varieties of broad bean seeds. With increasing doses of the microwave fi eld energy a decrease in protein solubility was observed. Satisfactory reduction in trypsin inhibitors at the level of 70-75% and highest protein digestibility were obtained by using a microwave fi eld with energy dose of 1000 J/g of seeds. Conclusion. It can be concluded that the optimal dose of microwave energy fi eld which will produce a relatively low activity of trypsin inhibitors and the highest protein digestibility together with maintaining solubility of broad been seeds was 1000 J/g seed. https://www.food.actapol.net/volume11/issue2/9_2_2012.pdf trypsin inhibitor in vitro protein digestibility microwave fi eld broad bean seeds eng Wydawnictwo Uniwersytetu Przyrodniczego w Poznaniu Acta Scientiarum Polonorum Technologia Alimentaria 16440730 2012-06-30 11 2 201 207 article Iwona Mentel 1 Ewa CieĹ›lik 1 Izabela WaĹ‚kowska 1 Krzysztof Sieja 1 Malopolska Centre of Food Monitoring and Certifi cation, University of Agriculture in Krakow Background. The artichoke (Cynara scolymus L.) is a perennial plant belonging to Asteraceae family. It is less popular vegetable in Poland but very valuable from nutritive and medicinal points of view plant. Material and methods. The experiments were conducted in 2008 and 2009 on fi ve artichoke varieties: ‘Deutscher Hybrid’, ‘Emerald F1’, Green Globe’, ‘Gros Camus de Bretague’ and ‘Kerlouan’, grew in Poland, France and Austria. The experimental material was assessed for: dry mass, protein, ash, vitamin C and dietary fi ber contents and some mineral components (calcium, magnesium, phosphorus, potassium, sodium, iron, zinc) levels. Also the energy value and total carbohydrates content were calculated in the vegetable. Results. Among assessed varieties, the highest contents of such components as: dry mass (total solids), carbohydrates, ash, vitamin C, sodium, potassium, magnesium, iron were found in ‘Gros Camus de Bretague’. The hearts of that artichoke had also higher energy value than others. Whereas the lowest ash, phosphorus, sodium, potassium and magnesium were noticed in ‘Kerlouan’ variety. But the highest values of dietary fi ber was observed in that variety. Conclusions. Basing on performed assessments the differences in nutritive components and dietary fi ber, between analysed vegetable varieties were found. https://www.food.actapol.net/volume11/issue2/10_2_2012.pdf artichoke energy value nutritive components and dietary fi ber eng Wydawnictwo Uniwersytetu Przyrodniczego w Poznaniu Acta Scientiarum Polonorum Technologia Alimentaria 16440730 2012-06-30 11 2 209 212 article Edyta MÄ…dry 1 Aleksandra Lisowska 2 Philip Grebowiec 2 JarosĹ‚aw Walkowiak 2 3 Department of Physiology, PoznaĹ„ University of Medical Sciences, Poland Department of Pediatric Gastroenterology and Metabolism, PoznaĹ„ University of Medical Sciences, Poland Department of Human Nutrition and Hygiene, PoznaĹ„ University of Life Sciences, Poland Background. There are no long-term prospective studies assessing the impact of the vegan diet on vitamin B-12 (B-12) status. Many vegans take B-12 supplements irregularly or refuse to adopt them at all, considering them to be “unnatural” products. The use of B-12 fortifi ed food may be an alternative. Therefore, we aimed to estimate the long-term effect of a vegan diet on serum B-12 concentrations in healthy omnivore adults, comparing the infl uence of natural products consumption and B-12 fortifi ed food. Material and methods. A fi ve year prospective study was carried out comprising 20 omnivore healthy adult subjects, who moved to strict vegan diet for 5 years. Ten volunteers followed vegan diet based entirely on natural products, while the remaining ten subjects consumed food fortifi ed in B-12. In all subjects serum vitamin B-12 concentration was determined before and 6, 12, 24 and 60 months after the implementation of the diet. Results. A signifi cant decrease (p < 0.0002) of serum B-12 concentrations in the whole studied group was noted after 60 months of vegan diet. However, observed changes were in fact limited to the subgroup consuming exclusively natural products (p < 0.0001). Conclusions. Transition from omnivore to vegan diet is associated with the risk of vitamin B-12 defi ciency. B-12 fortifi ed products might constitute a valuable alternative in vegans refusing to take vitamin supplements. https://www.food.actapol.net/volume11/issue2/11_2_2012.pdf vegan diet vitamin B-12 risk of defi ciency vegetarianism