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Oxidative stability of oils, fats and fatty food products can be affected by many factors such as oxygen, light, heat, metal ions and enzymes used and finally it brings about oxidative corruption. This study has been done to survey the role of Dorema aucheri extract in oxidative stability of fish oil (under microwave heating) and comparising that with BHT synthetic antioxidant. Concentrations of 250 and 500 ppm extracts of Dorema auchri and BHT 200 ppm were added to fish oil and a fish oil sample without the addition of antioxidant was considered as control, Then they were sampled after putting in microwave at time periods 0, 3, 6, 9, and 12 minutes. Chemical oxidative indicators (peroxide, free fatty acids and thiobarbituric acid) were surveyed. According to the results, in all times putting in microwave the amount of peroxide, free fatty acids and thiobarbituric acid  in the treatments that contained extract, were lower than the control treatment, but were higher than the treatment that contained  BHT. A significant difference wasn^'t seen among the treatment that contained 250 ppm of extract and the treatment that contained BHT (p>0/05). According to the results, because of significant difference of samples contained extract with control sample and the lack of significant difference sample containd 250 ppm extract with BHT, it would be expected that Dorema aucheri  extract as antioxidant can be used  in food industry in maintenace of fish oil.

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The effects of adding refined cod liver oil-  rich in omega 3- in three forms (fish oil,  O/W emulsion, gelled oil-in-water emulsion) to sausage from silver carp (Hypophthalmichthys moltrix) was investigated. In this regard, such properties of the sausage as its physicochemical, sensory, microbiological, texture, color, cooking loss and oxidative stability of enriched sausages were assessed. The results of proximate composition analyses showed that there was no difference between enriched formulated fish sausage (p> 0.05). pH ranged from 6.52 to 6.72 and decreased during storage. Enrichment of fish sausage caused to higher ω-3 PUFAs content, especially EPA and DHA, and decreasing significantly the ω-6/ω-3 ratio from 22.3 to 9.85. The control and fish oil treatments showed significantly higher thiobarbituric acid value during storage (p<0.05). Cooking loss was lower in gelled emulsion than other formulations. Texture analysis results showed higher hardness in gelled emulsion sausages than the others. Sensorial tests showed that the gelled emulsion sausages had higher acceptability scores. As a result, gelled emulsion was demonstrated to be a suitable delivery system in fortification of fish sausage.

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The yield and quality of oil extracted from common kilka (Clupeonella cultriventris caspia) through a novel extraction technique with supercritical fluid CO₂ and also ethanol co-solvent extraction at 30 MPa pressure and 58°C temperature of for 90 min were compared. Addition of ethanol co-solvent significantly increased the total oil yield (p˂0.05). Moreover, the qualitative characteristics of the extracted oil with ethanol modified the solvent acidity, peroxide and TBA index considerably less than the oil extracted by supercritical fluid CO₂. Fatty acid composition of the oil extracted with the two extraction methods showed there was no significant difference in SFA and PUFA fatty acids (p˃ 0.05). In general, the two methods used in this work didn’t considerably affect the fatty acid composition of the extracted oil.

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Aims: Increasing the aquatic consumption, developing aquaculture, and the need for aquatic food production will make unclear the availability to fish oil in the future. The aim of this study was to investigate the effect of replacement of fish oil by grape seed oil on growth indices and protease enzymes activity in Rainbow Trout.
Materials & Methods: This study was conducted on 450 Rainbow Trout during a 60-day period. In this study, control diet (A) containing 100% fish oil and 25% (B), 50% (C), 75% (D), and 100% (E) grape seed oil were used instead of fish oil. The data were analyzed by Graph pad prism and SPSS 20 software, using one-way ANOVA test.
Findings: The highest final weight and weight gain was in diet C and the lowest was in D, having a significant difference. Specific Growth Rate (SGR) and Protein Efficiency Ratio (PER) had no significant difference. The highest and lowest feed conversion ratio (FCR) was observed in diets E and C, respectively, with a significant difference. The highest fat efficiency was in diet C. The highest feed efficiency was in diets C and D and the lowest was in E, and the diets were not significantly different. The most activity of pepsin and trypsin was observed in pyloric additions in diet C and in intestine in C and D. The optimal amount of fish oil replacement was satisfied by grape seed oil 50% (diet C).
Conclusion: The diet containing 50% fish oil and 50% grape seed oil is effective in improving the growth indices and activity of pepsin and trypsin enzymes in Rainbow Trout.

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Aim: The objective of the current study was to evaluate the effectiveness of various extraction techniques, namely supercritical carbon dioxide (SC-CO₂), ultrasound, and enzymatic methods, in comparison to the conventional wet reduction method, in terms of oil yield, quality attributes, and fatty acid composition in common kilka oil.
Materials & Methods: Mentioned methods were used to extract fish oil. Then, their quality oxidation, including PV, TBA, FFA, and CD, and fatty acid composition were evaluated.
Findings: The study's findings revealed that the SC-CO₂ extraction method exhibited the most favorable outcome in terms of extraction yield, achieving a remarkable rate of 89.6%. The lowest oxidation indexes including PV (1.78 ± 0.19 mmol.kg^-1), TBA (0.54 ± 0.03 mg MA.kg^-1), FFA (35.49 ± 0.52 mg FFA.g TAG^-1), and CD (7.61 ± 0.34 %) was found in oil extracted with SC-CO₂ method. The fatty acid profile of oil extracted by SC-CO₂ exhibited higher polyunsaturated fatty acid (PUFA) (29.81 ± 0.27) and lower saturated fatty acid (SFA) (27.64 ± 0.20) and monounsaturated fatty acid (MUFA) (34.78 ± 0.67) than those obtained by the other extraction methods (p > 0.05). The n-3/n-6, PUFA/SFA, and EPA + DHA/C16 ratios were higher for oil extracted by SC-CO₂ than the other three methods. Conclusion: The common kilka oil, extracted through supercritical carbon dioxide (SC-CO₂), can be regarded as an abundant source of crucial polyunsaturated fatty acids belonging to the n-3 series.
 

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Omega-3 polyunsaturated fatty acids (ω-3PUFAs) have gained increasing interest in recent years due to their beneficial effects in maintaining heart health and regulating blood pressure, improving brain function, strengthening memory, and reducing depression. Fish and algae are known as the main sources of ω-3PUFAs. In the meantime, extracting fish oil from less-exploited species or fish waste not only creates higher added value, but also reduces environmental pollution caused by the process of disposal of fishery waste. In this study, the most common methods of oil extraction from marine sources, such as solvent-based methods (Soxhlet, Bligh and Dyer, and Folch Methods), supercritical fluid extraction (SFE) and enzymatic hydrolysis, along with their advantages and disadvantages, were investigated. Among them, Soxhlet extraction provides a high yield of lipids; Of course, choosing the right solvent is the most important factor in the effective extraction of lipids. However, continuous heating at the boiling temperature could lead to lipid oxidation and degradation of heat liable compounds. Therefore, development of alternative extraction and purification methods based on the use of green technologies and the sustainability principles, avoiding the use of organic solvents and high temperatures, is needed in order to produce omega-3 polyunsaturated fatty acids of higher purity and quality. Supercritical fluid extraction with environment-friendly solvents and enzymatic hydrolysis are the most promising green technologies for extracting fish oil, whereas pressurized extractions are suitable for extracting microalgae oil.

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In this study, the effect of different hydrolysis times (45, 90, 135, 180, and 225 minutes) by alcalase enzyme on the yield and quality of oil extracted from common kilka fish (Clupeonella cultriventris caspia) was investigated. The results showed that the highest extraction yield (40.41%) was in the hydrolyzed treatment for 135 minutes, which was not significantly different from other treatments. The qualitative indices of TBA, FFA, and CD of the extracted oils increased by increasing hydrolysis time, so the highest value of the mentioned indices was at 225 minutes, while the highest value of the PV index was at 180 minutes. Because the treatment of oil extracted in 45 minutes had lower values in the investigated oxidative spoilage indicators, it was selected as the treatment. The composition of its fatty acids was investigated, and it was found that monounsaturated fatty acids were the predominant fatty acids. Also, the amounts of saturated and polyunsaturated fatty acids did not show significant differences (p < 0.05). According to the obtained results, it was found that different hydrolysis times have different effects on the yield and quality of the obtained oil. Therefore, more research and studies are needed to fully investigate the effect of hydrolysis time on the quality characteristics of the oil extracted from Kilka fish.
 

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In this research stirred yoghurt prepared by addition of three sources of omega-3s; encapsulated fish oil, flaxseed oil and mixtures of the two oils at four levels (0, 650, 1625 & 3250 mg/1000 ml) and two addition step (after heating and after incubation step). Experiments were carried out in three replicates and a completely randomized factorial design was used for statistical analysis. Oxidative stability and fatty acid profiles were determined during the first, tenth and twentieth of storage time. The peroxide values and thiobarbituric acid values of enriched yoghurt with fish oil and enriched yoghurts after heat treatment are significantly highest. Polyunsaturated fatty acids and omega3 of enriched yoghurt with flaxseed oil is significantly higher than other samples. Therefore, it could be achieve the stirred yoghurt with higher oxidative stability by enrichment with flaxseed oil after heat treatment.

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An 8-week feeding experiment was carried out on beluga (Huso huso) juvenile to evaluate the effects of different levels of fish oil containing n-3 highly unsaturated fatty acids (n-3 HUFAs) on fish growth and fatty acid composition. The requirements of beluga juvenile for n-3 HUFAs were studied by feeding fish diets containing six different levels of n-3 HUFAs ranging from 1.56 to 17.25% (% of total fatty acids). Weight gain, feed conversion ratio, condition factor, specific growth rate and protein efficiency ratio were not significantly different among dietary treatments, nor was the body composition (including: moisture, protein, lipid and ash) of beluga juvenile (P> 0.05). There were no significant differences among plasma protein, glucose, cholesterol and triglyceride contents of dietary treatments (P> 0.05). However, haematocrit values were significantly lower in diets 1 and 2 (P< 0.05). The fatty acid composition of fish showed a pronounced change from the initial carcass with fatty acid composition changes in experimental diets. The fatty acid composition of the beluga carcass fed on diets containing various levels of n-3 HUFAs reflected the dietary fatty acid composition. The n-3 HUFAs contents of the lipids of fish increased with an increase in dietary n-3 HUFAs levels. Results suggested that minimum levels of n-3 HUFAs in diet have no effect on growth and n-3 HUFAs are not a restrictive factor on growth in beluga.

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One of the many ways that encapsulation are used is the complex coaservation techniques. The purpose of this study was to evaluate the effect of fish oil percentage(1%, 3% and 5%),  total biopolymer percent (1%, 3% and 5%) and  homogenizer speed (7000, 9000 and 11000 rpm) on the physicochemical and oxidative stability of produced powders. To this end, the response surface method was used in the central composite design. Optimized emulsion obtained in gelatin and gum coating (1: 1 ratio) contains (fish oil 1%, total biopolymer percent 1%, homogenizer speed 7000 rpm) which and encapsulation efficiency is 97.97% , and  In  order to evaluate the oxidative stability of the treatments, they were placed at 4 ° C for 3 months. The results of the study showed that by increasing the percentage of fish oil, the  powder  lighteness  index  and whiteness decreased and the  yellowness  index   increased. The results of the study the rate of oxidation showed that thiobarbituric acid (TBA) amount were significantly lower in encapsulated samples than in control samples also, in a encapsulated sample containing vitamin E, the amount of thiobarbituric acid in the first month was significantly lower than the other periods  in compared to with the control sample.

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Kilka fish oil is highly susceptible to oxidation due to high amounts of unsaturated fatty acids. One of the methods used to protect unsaturated oils from environmental damage is the encapsulation process. The purpose of this study was to investigate the effect of encapsulation process on reduction of Kilka fish oil oxidation. The purpose of this study was to investigate the effect of type and concentration of wall materials on encapsulated fish oil properties. The mixture of xanthan and lepidium sativum (Shahi) seed gum was used in 100: 0, 50:50 and 0: 100 ratios as the continuous phase of emulsion. Concentration of solid material in wall solution was chosen at 30, 40 and 50%. A homogenizer ultraturax was used to prepare nanomulsions and a high pressure homogenizer was used to produce microemulsion. The results showed that the size of the capsules prepared with mixture wall in all concentration, xanthan gum at 40 and 50% concentration and capsules with shahi seed gum at 30% concentration was in the range of nano (below 100 nm). All microcapsules had a size below 10 micrometers. Zeta potential was negative for microcapsules and nanocapsules and the lowest and highest zeta potentials were related to capsule with mixture and shahi seed gum walls respectively. The nanocapsules showed higher efficiency of Kilka fish oil encapsulation than microcapsules. The images of the Scanning Electron Microscope represent a suitable network and uniform wall cover around the capsules, and structural fractures were not observed. The results of this study suggest using of fish oil microcapsules with shahi gum wall at 40% concentration, fish oil nanocapsules with mixture of xanthan and shahi gum wall at 40% concentration, and fish oil nanocapsules with 30% xanthan gum due to good properties for oil storage.
 

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However, the beneficial effects of fish oil, which is fortified in omega-3 fatty acids, is known. But its high sensitivity to oxidation and the formation of undesirable compounds has limited its use in food systems. Therefore, the purpose of this study was the encapsulation of fish oil in chitosan-stearic acid nanogel, by Pickering emulsion method and import it into a food system (Gummy candy) and investigation the physicomechanical properties of the product. Initially, chitosan-stearic acid nanogel was created by self-assemble method and the results of FTIR confirmed the successful connection between chitosan and stearic acid. Also, SEM image showed that the nanoparticles formation was spherical nearly. In the next step, fish oil Pickering emulsions were prepared in different concentrations using chitosan-stearic acid nanogel and used in formulation of gummy candy and in continue, the texture profile analysis (TPA) and also the measurements of the color indexes of the samples were performed. The results of TPA showed that the existence of the nanogel, increased the Springiness (from% 88.5 to% 92.5) and adhesion (from Ns 0.33 to Ns 0.63) and reduced the hardness (from N 178.6 to N 125.8) of texture of gummy candy samples. On the other hand, the presence of fish oil reduced all of the texture indexes. About the color indexs, the nanogel decreased the L (from 58.13 to 56.46) and a (from -5.5 to -4.4) indexes. Also, the results showed that fish oil in combination with nanogels reduced the color indexes.

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In the past decades, numerous efforts have been made to systematize the process of developing new food products from idea generation to product commercialization. So, studies on consumer behavior in foods have led to particular changes in the processing of food and beverage products. Food industry is one of the most competitive industries in the country's economy, and manufacturing new products is one of the key pillars of success in food and drink processing units. On the other hand, the change in the taste and expectations of customers about the processed products makes the creation of new products inevitable in accordance with their demands. The present paper consists of two parts introducing "the process of developing a new food product" and the results of the research on "developing omega-3 enriched ice cream using this approach." The first part is the author's experience in teaching designing and manufacturing of food products in a number of abroad universities and research centers. The second part (case study) is an applied research carried out at the Animal Science Research Institute of Iran. The purpose of this article is to open up a window towards the science of food design and development, which in our country, unfortunately, has been systematically and scientifically less attention paid to it. This article will introduce researchers and experts in the food industry to the process of developing a new product and will be a useful guide for those interested in this science.