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Methods for detention of lipid rancidity
117-120Views:990There are various methods available for measurement of lipid oxidation in foods.Changes in chemical, physical, or organoleptic properties of fats and oils during oxidation may be monitored to assess the extent of lipid oxidation. However, there is no uniform and standard method for detecting all oxidative changes in all food systems. The available methods to monitor lipid oxidation in foods and biological systems may be divided into two groups. The first group measures primary oxidative changes and the second determines secondary changes that occur in each system.
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Review on the fatty acid profile and free fatty acid of common carp (Cyprinus carpio)
99-105Views:451Carp or ponty in Hungarian, is considered commercial freshwater fish, which is an adaptable species in both wild and cultured conditions. Carp has high nutritional value content, favorable taste, it is rich in protein, and low in saturated fat. The nutritional content in fish is composed of many chemical constituents and influenced by many factors. One of the components that its content may be different due to internal and external factors is fatty acids, which may vary depending on endogenous and exogenous factors. The endogenous or internal factors include the genetic, size, sexual maturity, and life cycle phase. While microclimate, water quality, quality of food or diet habit, and the amount of available food or starvation are considered as exogenous or environmental factors. Freshwater fish has the ability to convert essential fatty acid into long chain polyunsaturated fatty acid like AA, EPA, and DHA. Most results showed that palmitic acid and oleic acid were the dominant SFA and MUFA in carp both for wild and farmed carp in all seasons. The PUFA for wild carp was mainly dominated by DHA, while on farmed carp by LA. It confirmed that high LA content in farmed carp was related to the diet habit. The amount of lipid and FA were changed in line with the season. Even the statistical analysis showed no significant difference, but some studies showed a contrasting result. Moreover, most obtained results acknowledged that FA tends to decrease during the spawning period. The amount and composition of FA were affected by the total lipid content. The lipid must be broken down into simpler compounds such as FA or FFA for the metabolism of fish. The result of metabolism then transported into the utilising tissue and used as energy.
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Intensity of free radical processes in the leaves of arboreal plants under act of industrial dust borne extracts
83-87Views:168The influence of industrial pollutants on the intensity of lipid peroxidation in the assimilatory organs of arboreal plant was investigated. The differential changes of the probed indexes are set depending on the species. Information is got can testify to participation of lipid peroxidation products in forming of reactions-answers of arboreal plants on influence of industrial dust borne extract with content of heavy metals. Determination of level and rates of accumulation of Zn, Ni, Pb and Cd, in the leaves of arboreal plants in the conditions of different
contamination level allowed to take species to two groups. To the first (phytoextraction potential exceeds a base-line level in 10 times) belong Populus bolleana Lauche, P. italica (Du Roi) Moench, Picea pungens Engelm and Sorbus aucuparia L. To the second (exceeds a base-line level from 5 to 10 times) belong Acer negundo L., Aesculus hippocastanum L., Betula pendula Roth and Tilia cordata Mill. The most substantial increase of peroxidation secondary product content (more than in 2.5 times) is peculiar for B. pendula, A. hippocastanum and P. pungens Engelm., that well conforms to the rates of heavy metals translocation, it has however species-specific character. -
Violation prooxidative-antioxidant stability at maize shoots at different level of accumulation of cadmium and nickel
89-94Views:184Joint influence of cadmium and nickel was investigated on the feature of their accumulation by the vegetative organs of 10-days' old maize shoots. It was established that most intensively noted metals are taken in by the roots of shoots in the first 7 hours stressing influencing, while in leaves they appear only after a 7-hour long exposition. It was stated that the absorption process of the noted metals by a root system is carried by two-phase character. The indexes of inner-tissue contamination are calculated. Activating by the cadmium and nickel ions of lipid peroxidation as marker of the stressing influencing, and also was shown the proper increase of intensity of functioning of ascorbate peroxidase as the antioxidant enzyme protection of cell.
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Testing of Various Solvents for the Preparation of Lipid Samples for Use in Thin Layer Chromatography
49-50Views:173We analyzed the muscular tissue of 6 sheep. Lipid extraction was performed using the Handson and Olley method. TLC separation was performed using 4 separation systems and the best separation method was determined. Visualization was done using a mixture copper acetate and phosphoric acid, at 150 oC.
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Definition antioxidant activity of selenium-enriched food sprout, as well as their microbiological analysis
25-30Views:658In this present study, we prepared selenium-enriched food sprouts, where the antioxidant capacity was analysed, we also determined their microbiological status. We took into account the fact, we choose micronutrients to our treatment, that selenium can be delivered to the body by a small amount with the most widely consumed food.
We focused during our research to determine that the increasing concentrations of selenium treatment, in which we used sprouts, knowing fully well that it has an impact on aboriginal antioxidant capacity of sprouts, which is mainly due to high vitamin content of sprouts.
Furthermore, we think it is important to make microbiological analysis, because germination conditions, for example temperature, pH, all this will create an ideal environment for the growth of microorganisms. So we had goal to determine, how the used selenium concentration affect the total plate count, coliform bacteria count and Staphylococcus aureus count of sprouts.
We determined the aboriginal water-soluble and lipid-soluble antioxidant capacity of sprout with the PHOTOCHEM chemiluminometer and we applied pour plate technique for the mapping of the mycrobiological state of sprouts.
Experimental results are evaluated, we state that increasing concentrations of selenite or selenate treatment, is primarily water-soluble antioxidant capacity of sprouts was affected. The water-soluble antioxidant capacity of wheat sprout was much higher than the measured values in pea sprout, this may be linked to what we measured. That is much higher ascorbic acid content in case of wheat sprout, which is well known as one of the most important antioxidant properties compounds of wheat sprout.
We conclude from the results of the microbiological, that the highest concentrations of selenite or selenate treatment has a relative significant anti-microbial effect in case of wheat sprouts. Coliform and total plate count showed no clear decreasing tendency, although the values of treatments in both cases obtained were below the control values.
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Effect of raised level α-linolenic fatty acid diet on broiler meat quality
29-33Views:238The aim of our investigation was to determine the effects of increased α-linolenic content in food on the colour, total pigment content, organoleptic characteristics and oxidative stability of poultry meat. The experiment was carried out with 1200 Ross-308 cock chicklings. Birds were fed three-phase diets, contained four different fat sources: lard, sunflower oil, flaxseed oil and soybean oil. According to the experiment, the different oil sources had no effect on growth performance, but the fatty acid composition of diets was reflected in the meat fatty acid profile. We could detect just slight change in colour in the treated meat, which was not caused by the decreased pigment content. The detected change in colour during the storage was not in relation to initial PUFA content. TBA level did not prove the accelerated lipid peroxidation which was expected in case of higher α-linolenic containing the meat. The data obtained in meat storage trial, could not prove clearly the negative effect of the higher α-linolenic content of the meat.
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Large Scale Measurement of the Total Antioxidant Capacity of Different hungaricum Fruit and Vegetable Samples with Photochem Chemiluminometric Device
300-304Views:258In our present study, we performed a quick test of the antioxidant capacity of domestic fruit and vegetable cultivars with a PHOTOCHEM® instrument (Analytik Jena AG, Germany). The instrument is special because it can measure both the total lipid-soluble antioxidant capacity (ACL method) and the total water-soluble antioxidant capacity. Another advantage of the system is its quick measurement. With similar instruments, such measurement can take several hours, while PHOTOCHEM® can perform it within a few minutes.
In our model studies, we examined the changes in the antioxidant capacity of sour cherry, green pepper, carrot, pumpkin, red beet and Brassica sp. cultivars. We aimed to determine how suitable the instrument is for quick, routine measurements in the case of the different horticultural products and which species have high antioxidant capacity values.
On the basis of our examinations, we can state that the PHOTOCHEM® system is suitable for routine, semi-automated measurements of the total antioxidant capacity at several vegetables and fruits. Besides this, the system can be used for testing the quality of food products, for monitoring storability in post-harvest technologies, and for special breeding programmes and for physiological and biotechnological studies. -
Impact of chronic heat stress on digestibility of nutrients and performance of meat type ducks
51-55Views:376The aim of the study is to determine the effect of vitamin and mineral supplement under permanently high environmental temperature (30±1 °C) on the digestibility of nutrients, performance and furthermore the composition of duck meat in the growing period. A total of four hundred mixed sex 14 days old Cherry Valley type hybrid ducks were used for the study. Two experimental diets were formulated in the study (control and vitamin E, C and zinc supplemented diet). Based on the results the following conclusions were drown: the antioxidant defence system plays an important role in the reduction of heat stress generated lipid peroxidation process. Feed additives which have direct or indirect antioxidant effects can reduce the negative effects of heat stress on the ducks performance and meat composition. Digestibility of nutrients (Dry Matter, Crude Protein, Crude Fat) was not affected by antioxidant supplementation under chronic heat stress (30±1 °C). The performance was affected significantly by Vitamin C and E and zinc supplementation under heat stress (P<0.05). In the treated group the daily weight gain (dWG) increased and the feed conversion ratio (FCR) was improved significantly (P<0.05). The energy and protein conversion was decreased also significantly (P<0.05).