Freezing Of Fish Research Articles

Effects of Frying, Freezing, Boiling, and Thawing Processes on Proximate, PH and Energy Values of Fresh (Oncorhynchus mykiss)

Objective/Background: Oncorhynchus mykiss is the most popular type of freshwater fish consumed by Iranians. It has delicious taste and high nutritional value. The purpose of processing and preserving fish is to get it to the end consumer in a good, usable condition. Methods: This study is a descriptive study that compares and determines the analysis results of proximate, protein, and fat between fresh and processed fish using the standard method of AOAC and compares the analysis of this study with that of other studies. The effect of the processing methods’ nutritional composition is determined. In addition to fresh fish, 5 treatments are used for the 5 different methods of fish processing. Results: The fresh fish and the different processed samples were analyzed by standard AOAC methods, and their pH was measured. After analyzing the macronutrient compounds of different samples, the energy values were then calculated in kcal. The moisture content ranged from 72.50% for fresh fish to 19.50% for frozen fish, while the fat content ranged from 8.09% for fresh fish to 64.47% for frozen fish. The ash contents were found to range from 4.82% to 5.82%, while the protein contents were found to range from 10.47% to 13.59%. The results showed that quick freezing of fish preserved nutrients with a high percentage of energy. This sample was recommended for consumption, followed by samples thawed in oven and in hot water. The fried and boiled samples were in the next stages of quality and energy values. Conclusions: Because the fat content of this type of fresh fish is high, and if fish feed and its nutrition are protein materials with high biological value, it will be useful to increase the percentage of meat protein for it to grow.

Length-weight relationship and condition factor of bullet tuna (Auxis rochei Risso, 1810) in the waters of Mamuju District, West Sulawesi Province, Indonesia

Abstract. Nur M, Tenriware, Nasyrah AFA. 2023. Length-weight relationship and condition factor of bullet tuna (Auxis rochei Risso, 1810) in the waters of Mamuju District, West Sulawesi Province, Indonesia. Biodiversitas 24: 5253-5259. Bullet tuna (Auxis rochei Risso, 1810) is a fish species with a wide distribution and high socioeconomic value. Furthermore, it serves as a primary catch for fishermen, offering a crucial protein source to the community and generating employment opportunities in various sectors, including fresh fish sales, fish freezing, drying, and smoking industries. To maintain the sustainability of bullet tuna, it is necessary to know basic information regarding the study of length-weight relationship and condition factors because it is related to the fish growth and condition of fish in their habitats. Therefore, this study aimed to determine the growth pattern of bullet tuna, fundamental data for sustainable management efforts. The investigation was conducted from May to August 2023, and the sample fish were collected at the Fish Landing Port (PPI) Kasiwa, Mamuju District, West Sulawesi Province. Analysis was conducted in the Fisheries Department Laboratory, Sulawesi Barat University. The study procedures involved determining the total length and weight of the fish using a measuring instrument and digital scale, respectively, with accuracies of 0.1 mm and 0.01 g. Based on the data collected, 302 samples were obtained, consisting of 187 males and 115 females. The results showed that the relationship between the length and weight of bullet tuna yielded the equations of W = 0.027L3.4783 for male fish, W = 0.0052L3.2732 for female fish, and W = 0.0033L3.4141 when combined. A t-test was conducted on the coefficient b, showing a calculated t-value greater than the tabulated values. It indicated that bullet tuna belongs to the negative allometric growth type (minor) (b<3), where body weight increased faster than body length. Condition factors for male and female fish ranged from 0.3186 to 1.6961 and 0.6990 to 1.5011, respectively, with averages of 0.9957 and 0.7997. It indicates that the bullet tuna fish are in good condition in Mamuju District water.

Расчет температурных режимов технологии подмораживания и хранения рыбы с учетом значений криоскопических температур

Рыба-сырец (свежая рыба) относится к скоропортящейся продукции. Обработка холодом, продлевающая сроки годности пищевой рыбной продукции, нашла широкое применение в рыбной отрасли в виде охлаждения и замораживания. Однако ввиду возрастающих объемов производства объектов аквакультуры возникла необходимость в развитии альтернативных охлаждению методов консервации и хранения пищевой рыбной продукции. Технология подмораживания позволяет длительное время хранить продукцию без добавления льда за счет контролируемого вымораживания воды в ней. Известно, что допустимый диапазон вымороженной воды в пищевой продукции при подмораживании составляет от 30 до 50 %. Ограничение процента образования льда в продукции связано с тем, что увеличение доли вымороженной воды в пищевой продукции приводит к необратимым изменениям показателей качества, обуславливающим их снижение. Температура замораживания, позволяющая достичь необходимого процента льда, зависит от криоскопической температуры замерзания тканевого сока внутри рыбы. Данный параметр варьируется с учетом вида рыб. Цель работы – научное обоснование технологии подмораживания пищевой рыбной продукции для дальнейшего промышленного внедрения на всех этапах производственной цепи: от производителя до конечного потребителя, обеспечивающего единую непрерывную холодильную цепь. Определены значения криоскопических температур и диапазоны хранения подмороженных рыб семейства лососевых (Salmonidae), осетровых (Acipenseridae), веслоносовых (Polyodontidae) и карповых (Cyprinidae). Показано, что абсолютные значения температур хранения подмороженной пищевой рыбной продукции, представленные в ТР ТС 040/2016 (п. 57в), соответствуют не всем объектам исследования. Хранение при температурах, указанных в регламенте, приводит к увеличению количества вымороженной влаги и, как следствие, к потере массы при размораживании и ухудшению органолептических свойств пищевой рыбной продукции. На основании результатов исследования формируется предложение по внесению изменений в п. 57 ТР ТС 040/2016 и разрабатывается технологическая инструкция на производство подмороженной пищевой рыбной продукции. Fish raw (fresh) fish refers to highly perishable products. Cold treatment, which extends the shelf life of fish food products, has found wide application in the fish industry in the form of cooling and freezing. However, due to the increasing production volumes of aquaculture objects, it became necessary to develop alternative methods of preservation and storage of fish food products to refrigeration. Partially freezing technology allows to store products for a long time without adding ice due to controlled freezing of water in it. It is known that the permissible range of amount of frozen water in food products during partially freezing is from 30 to 50 %. The limitation of the percentage of ice formation in products is due to the fact that an increase in the proportion of frozen water in food products leads to irreversible changes in quality indicators, causing their decrease. The freezing temperature to achieve the required percentage of ice depends on the cryoscopic freezing temperature of the tissue juice inside the fish. This parameter varies depending on the type of fish. The aim of this work was to scientifically substantiate the technology of partially freezing fish food products for further industrial implementation, at all stages of the production chain: from the manufacturer to the end consumer, providing a single continuous refrigeration chain. The values of cryoscopic temperatures and storage ranges for partially frozen fish of the salmon (Salmonidae), sturgeon (Acipenseridae), paddlefish (Polyodontidae), and cyprinids (Cyprinidae) families were determined. It is shown that the absolute values of the storage temperatures of partially frozen fish food products, presented in TR EEU 040/2016 (p. 57), do not correspond to all objects of study. Storage at temperatures specified in the regulations leads to an increase in the amount of frozen water and, as a result, to weight loss during defrosting and deterioration of the organoleptic properties of fish food products. Based on the results of the study, a proposal is formed to amend clause 57 of TR EEU 040/2016 and a technological instruction is developed for the production of partially frozen fish food products.

Effect of Freezing On Some Morphometric Features of Planiliza Abu ( Hekel,1843)

The present study attempts to determine the effect of freezing for different periods on preserved bodies of fish in the laboratory to keep for the research and diagnosis of taxonomic studies and not for consumption. It also endeavors to identify the effect of freezing on some morphometric features of the preserved bodies of fishes. Planiliza abu fish were used to conduct the present study. Fish were frozen by regular freezing in the home refrigerator freezer with temperatures reaching four degrees centigrade below zero. Freezing time is distributed over four months; biometric measurements of frozen fish have been taken in these periods represented by body total length, Standard length, and Head length in centimeters using a ruler vernier caliper in addition to body weight in grams by using a scale. Statistical data analysis for this experiment has been conducted to investigate the resulting facts of freezing periods and the effect of differences in freezing periods on these biometric measurements using Duncan's new multiple range test and Levene's test. Results showed no apparent significant differences related to the size in total length and standard length and weight, While measuring head length showed important characteristics of frozen fish, especially in the first and third month of the experiment. Most of the sources that deal with such research patterns are concerned with the freezing of fish intended for food and human consumption, and few of these studies are concerned with research freezing, such as preserving frozen fish specimens for analysis, even for some time. Attention to the importance of freezing for research studies related to fish because of the susceptibility of its meat to rapid deterioration, and therefore, may give wrong diagnostic results if the survey is between species from the same family or a diagnostic and taxonomic study between many species belonging to different families. Keywords: Body measurements, Coastal fish, External appearance, Ice crystals, Preservation.

Quality Assurance for Frozen Fish (Decapterus sp) Utilizing Fault Tree Analysis at PT XYZ (Fish Freezing Company)

Fish product quality is crucial, and any flaws in frozen fish, such as unpleasant odor, breakage, dents, tears, or texture damage, can negatively impact its overall quality. These defects can lead to reduced customer satisfaction and adversely affect the company's brand reputation. To enhance product quality, the company must establish an efficient quality assurance system and closely monitor the handling of raw materials. The main objective of this practical work is to identify potential risks of damage and develop strategies to prevent such incidents from occurring. The Fault Tree Analysis method is utilized to systematically identify and analyze the root causes of existing errors and find appropriate solutions to address the problem. The FTA results reveal 18 basic event factors that can cause damage to fish, including worker negligence during raw goods placement, inadequate use of plastic protection, lack of rubber carpets in baskets, failure to adjust freezing temperature properly, insufficient inspections, non-compliance with Standard Operating Procedures, improper fish arrangement, excessively hard freezing temperature, employee laziness and carelessness, absence of basket mats, prolonged freezing step, unset temperature checks, mishandling of raw goods due to a rush to finish quickly, and irregular temperature checking schedules. The study aims to understand the step-by-step process of handling flying catfish, identify the factors contributing to fish damage, and analyze the potential damage scenarios.

Study of Fish Markets and their Pattern of Raipur City

The state of Chhattisgarh is endowed with rich and varied inland fisheries resources, which include ponds, reservoirs and rivers. Chhattisgarh, the 26th State of India, was carved out of Chhattisgarh on November 1, 2000. Located in central India it covers an area of 135,133 sq km. Raipur is the capital of Chhattisgarh. Chhattisgarh is bordered by Bihar, Jharkhand and Uttar Pradesh in the north, Andhra Pradesh in the south, Orissa in the east and Chhattisgarh in the west. Fishermen of this area are mostly involved various technologies in fisheries over a period of time by trial and error, continuous observations, experiences and evaluation to use the traditional practices in this field. The fishermen from rural area may an important role in establishing smoked fish and demand of dried prawn in market and also holding strong traditional marketing system for wet and dried prawn and do sell it round the year. The specific objectives of this study were to the availability, consumption and landing pattern of fishes, to find the available setting place and using their fish dressing equipments, carrier bags reasons for adopting traditional practices by fish traders, fishermen & fisherwomen in local fish market of Raipur town. The list of fish whole seller/traders, fish seller, fishermen & fisherwomen were prepared as respondents with the help of equal interval method of random sampling. The finding reveal that there is a good market, demand and price for almost all the Indian major carps, verities of indigenous local & catfishes. But, the supply is less as per demand and also poor due to environment of this local fish market. The major constraint of fish market under ownership of Municipal Corporation and also established at one place and no cement floor, storage facilities (Ice plant/ unit) nearly, high transportation charges, non-availability of skilled labor, and with non-availability of electric current regularly for freezing of fish were the important difficulties encountered by fish seller in market of Raipur town. The development of this local fish market are expected to significantly contribute in reducing post harvest losses, enhance revenue and also improve the hygienic environmental effect and sanitary conditions in fish markets.

Effects of four multi‐compound freezing medium on the quality of red drum (Sciaenops ocellatus) during frozen storage

AbstractTaking air freezing (AF) as the reference, the effects of four types of multi‐compound freezing medium for cryogenic liquid quick‐freezing (immersion freezing, IF) on the freezing rate, quality and myofibrillar protein (MP) denaturation of red drum (Sciaenops ocellatus) fillets during frozen storage (−18°C) from days 0 to 90 were studied. Samples were gathered on days 0, 15, 30, 45, 60 and 90 for analysis. The results showed that IF groups (IF‐1: 20% ethanol, 30% propylene glycol, 10% sodium chloride aqueous solution; IF‐2: 20% ethanol, 20% propylene glycol, 10% glycerol, 10% sodium chloride aqueous solution; IF‐3: 20% ethanol, 20% propylene glycol, 10% polyethylene glycol, 10% sodium chloride aqueous solution; IF‐4: 20% ethanol, 20% propylene glycol, 5% glycerol, 5% polyethylene glycol, 10% sodium chloride aqueous solution) significantly shortened the time to cross the formation zone of maximum ice crystals while the freezing rate was 6.13 times higher than the AF group after adding 30% propylene glycol as the freezing medium. Furthermore, compared with the AF group, the IF groups significantly reduced losses in the water‐holding capacity, the myofibrillar fragmentation index, microstructure damage, texture characteristics, drip loss and water migration (P < 0.05). In addition, the MP of IF groups had higher maximum transition temperatures (Tmax1 and Tmax2), total sulfhydryl content, Ca2+‐ATPase activity and relative α‐helix content compared with the AF group. In conclusion, IF could significantly increase the freezing rate of red drum fillets, and slow down quality deterioration and denaturation of MP during frozen storage for 90 days (−18°C). In particular, IF‐2 (20% ethanol, 20% propylene glycol, 10% glycerol, 10% sodium chloride aqueous solution) was found to be more suitable for the immersion freezing of marine fish among the four multi‐compound freezing medium.

Phase change material‐assisted freezing of tuna: Impact on freezing process and thawing loss

AbstractDue to slow freezing, freezing fresh fish in a chest freezer often leads to deterioration while products are thawed. Many approaches have been conducted to deal with it. One of them is the application of Phase Change Material (PCM) in refrigeration systems. This study aims to investigate the ability of PCM to accelerate the freezing of fish in the household freezers. The tuna used was stored in the freezer with PCM, which was put on a surface wall cabinet then compared with storage in the freezer without PCM. Besides, the door of the freezer was also opened frequently (three times a day, 1 hr each time) to find out the effect of fluctuating temperatures and freezing operations for 60 hr. The parameters observed include the evolution temperature of the air cabinet and fish, energy consumption of the freezer, and thawing loss. Results showed that PCM accelerated the cooling rate of air cabinets and fish but could not suppress the fluctuation temperature. The quality of the frozen tuna improved, which was indicated by a decreased thawing loss parameter from 3.10% to 1.76%. Overall, this finding revealed PCM has significant potential to improve the fish freezing process.Practical ApplicationsThe household chest freezer is widely used to freeze fish by small and medium‐sized enterprises (SMEs). The most important factors in freezer preferences are simple operations and low energy consumption. But, the freezer worked at slow freezing, which caused higher thawing losses of the product. Hence, the application of PCM to the household freezer potentially improves the freezing process of the fish. So, sellers and retailers of fish could maintain their products without replacing the freezer with an advanced one.

Critical Control Point (CCP) on Freezing Hairtail Fish (Trichiurus savala) in PT Pan Putra Samudra, Rembang, Central Java

Hairtail fish (Trichiurus savala) is potential to have a rapid deterioration due to the high water and protein content in the body of the fish. One of the efforts to prevent or slow down the deterioration of layur fish is by freezing treatment. The freezing process also cannot be completely avoided from the emergence of potential hazards, therefore a way to prevent or suppress potential hazards is needed by applying the Critical Control Point (CCP). The descriptive method with data collection including primary and secondary data was used in this study. The freezing process of layur fish at PT Pan Putra Samudra starts from receiving, sorting, weighting, labelling, washing, wrapping with plastic and arranging in cartons, freezing, packaging, and frozen storage. The stages determined as CCP in the freezing of layur fish are in the sorting stage. At the sorting stage, quality checking is performed including organoleptic and microbiological tests. It also checks physical hazards such as hooks and nets. The sorting stage is determined as CCP because in the next stage it cannot prevent or reduce the potential danger that exists in fish. Fish that have gone through quality checking and exceeding the threshold will be put in a special fish reject basket.

Freezing and frozen storage of aquatic products: mechanism and regulation of protein oxidation

Freezing technology is currently an important preservation method for aquatic products. However, during the long-term freezing process proteins, which are the main components of muscle tissue, are inevitably exposed to an environment containing oxidative stress inducing changes in muscle protein structure. It leads to irreversible physical and chemical changes causing deterioration in the quality of aquatic products and reducing their nutritional value. Therefore, it is necessary clarify in depth to control oxidative damage of muscle during freezing and storage to gain more insight into the mechanisms of freezing-induced protein oxidation. The mechanism of protein oxidation in fish freezing, the effect of protein oxidation on fish quality, and the current regulatory methods for delaying protein oxidation were summarized in this paper review. The purpose is to provide a new research direction for the research and application of quality control in the process of fish frozen storage.

Sublimation Drying of Fish Products in the Arctic in the Production of Feed for Farm Animals

Introduction. The article considers biological resources of the Arctic, which is expedient to use in the production of fish meal for feeding farm animals. The aim of the research is to prove the usefulness of a continuously operating two-chamber line for sublimation drying of fish products using natural freezing of fish catch and a cheap source of thermal energy for drying: ethane, propane, butane (waste when cleaning natural gas and petroleum products of local enterprises), as well as microwave energy. Materials and Methods. A continuously operating two-chamber sublimation line is proposed, the chambers of which work alternately: one for the process of sublimation drying, and the other for loading and unloading processed products. The natural freezing of fish and thermal energy for the process of sublimation (drying) from the burning of waste gas are used whenever possible. When there is cheap electricity, it is advisable to use microwave energy for drying that makes it possible to shorten the drying cycle, ensure uniformity and simultaneity of drying the material up to 3–5% humidity without rearranging the trays along the height of the cart. Results. We propose the construction of a two-chamber sublimation line for large lump products and a sublimation unit based on microwave energy, which allows regulating the sublimation drying temperature within specified limits. Discussion and Conclusion. The presented design solutions of a large lump product sublimation drying line and sublimation unit using microwave energy are necessary for designing equipment based on digital technology.

The potential of cold energy extraction from a power plant regasification terminal for cold storage application

Cold storage is a chamber used for food preservation. The food is stored inside the cold storage at a specific temperature and relative humidity to slow down the deterioration process caused by pathogenic organisms. The type of food stored requires specific thermal conditions e.g 0-5 °C with RH of 80-90% for vegetables, 4-5 °C for milk processing, and -25 to -45 °C for quick freezing of fish. Cold energy from the LNG regasification process is a promising option for cold storage application. Normally, prior to supply to industrial users e.g power plants, the LNG is regasified by dissipating its cold energy to another working fluid of vapourizer e.g seawater in the Open Rack Vapourizer (ORV) or ambient air in the Ambient Air Vapourizer (AAV). Recovering this cold energy to cool the cold storage can significantly reduce the energy consumption in the cooling process. Simultaneously, it reduces greenhouse gas emissions. This study aims to investigate the potential of wasted LNG cold energy in a power plant’s regasification terminal, located in Aceh, as a source of energy to cool cold storage. The cooling load of cold storage under four different capacity namely 5, 10, 15, and 20 tons of fish is calculated and compared with the potential cold energy available. This study then concludes the cold storage capacity that meets the available LNG cold energy.

Energy Consumption Analysis in Katsuwonus Pelamis sp. Freezing and Storaging Process

A fresh fish has a short limited fresh time without treatment. To maintain quality and prevent spoilage, several treatments are carried out especially using a cooling method. In the fish storage industry, most energy consumed by cooling equipment. With the rising of energy prices, the frozen fish industries are looking for possibilities to reduce production costs by saving energy. Energy-saving assessment can be seen from the specific energy consumption (SFC) which is a comparison of the amount energy needed to produce a product (kWh/ton of product). This article will be discussed about data collection and analysis to get the value of SFC for process and storage in the fish freezing and storage services industry. The measurement result shows that the value of SFC for cold storage are 4.2 kWh/ton. The SFC used by the air blast freezer (ABF) with 5 tons capacity are 91 Wh/kg. The consumption of electrical energy in ABF is strongly influenced by matched between the capacity specifications of ABF and the number of fish to be cooled. If the 5 tons ABF is only filled less than 2 tons of fish, the SFC will increase more than 50% up to 145 Wh/kg.

Quantification and mapping of tissue damage from freezing in cod by magnetic resonance imaging

Freezing of fish is an important processing method that can extend the shelf life of the product but can also lead to significant damage to the tissue if performed incorrectly. In order to thoroughly evaluate different freezing protocols, a method to characterize the extent and distribution of damage from freezing is needed. Magnetic resonance imaging (MRI) was tested as a technique to map and quantify tissue damage from freezing in fish. Groups of packaged cod (Gadus morhua) loin were frozen to either −5, −20, or −40 °C, thawed and then imaged with a T2-weighted MRI sequence. Areas of damage appear as bright clusters in the muscle tissue. To provide repeatable, objective classification, image analysis using a convolutional neural network was then performed on the MRI data to identify regions of damaged tissue. As expected, the colder the freezing procedure, the less damage the process generally produced. Results show non-uniform damage throughout the fillet, with tissue damage due to freezing concentrated in the center of the fillet. This suggests that surface limited methods, such as hyperspectral imaging, may not fully capture the extent of damage due to freezing and thawing. The percent of tissue classified as damaged by the neural network generally correlated well with liquid loss (cor = 0.83).

Parameters that Affect Electricity Consumption in Fish Freezing. Case Study

Abstract Reducing energy consumption in industry has become an important aspect on a global scale. Energy efficiency is one way of reducing energy consumption and promoting competitiveness. Increasing energy costs, security of energy supply, emissions from energy production have shown that current freezer design solutions are not sustainable. The food industry has a common tendency, whereby energy costs are only of secondary importance, unlike other production costs, resulting in minimal monitoring of energy consumption. Electricity consumption for freezer operation amounts to 20 % of total electricity consumption. Within the framework of this study, electricity consumption for fish freezing and storing frozen fish and finished products, as well as the coefficient of performance (COP) for compressors and parameters affecting COP were analyzed. From the results it can be concluded that the specific consumption of electricity in freezing of fish is lower than that of frozen fish storage. The two-stage compressor COP ranges from 2.4 to 3.7, but the single-stage compressor COP ranges from 3.7 to 5.5. The pressure in the condenser and ammonia vapor temperature after the compressor is affected by the temperature of the water used to cool the condenser and compressors. As the temperature of the water used for cooling increases, the condenser and ammonia vapor temperature after the compressor increase, which in turn reduces the compressor COP.

The application of material handling in fish fillet production process of red snapper in PT X

Fish is one type of food that contains protein, fat, vitamins and minerals that are good in fulfilling necessary for human nutrition. Indonesia is a country with fisheries anda marine resources reaching 5.8 million km with a potential of 6.4 million tons of fish every year. PT X is one of the companies engaged in fish freezing in Indonesia which has exported many products to several countries. Production activities are the most dominant part carried out by PT X. A good production management system is system that regulates the smooth process of its production, besides that it is also determined by the proper handling of materials. In any companies, include PT. X, production activities are critical, thus a good production management is necessary to smoothing the production process and material handling. While, the material handling itself has a big portion in the operational cost. The purpose of this study was aimed to determine the application of material handling and the costs required in the process of handling red snapper fish in PT X. The results of the application of material handling that there are 8 directions of material transfer in the process of fish fillet production in PT X namely the transfer of material to Carbon monoxide’s (CO) room, transfer to Air Blast Freezer (ABF), transfer to packing room, transfer to cold storage and transfer from ABF to containers. From these transfer, the total cost of these material transfer per day in PT X is IDR 291,592.94.

Energy-Economic Analysis of Plate Evaporator using Brine-based Hybrid Nanofluids as Secondary Refrigerant

Energy and economic analyses of corrugated plate evaporator have been performed in this study by using brine-based hybrid nanofluids as secondary refrigerant for low temperature applications (milk chilling, ice making and fish freezing). Various hybrid nanofluids containing alumina with different nanoparticles (copper, silver and multi walled carbon nanotube) dispersed in ethylene glycol/water, propylene glycol/water, calcium chloride/water and potassium acetate/water brines have been considered. A comparison has been made based on overall heat transfer coefficient, evaporator size (heat transfer area), pump work, COP, annual cost and payback period. The maximum reduction in heat transfer area has been observed for PG brine-based alumina–silver hybrid nanofluid. Whereas, the maximum reduction in pump work and augmentation in COP have been obtained for PG brine-based alumina–MWCNT hybrid nanofluid. EG brine-based Alumina–Cu hybrid nanofluid yields minimum annual cost. Most of the nanofluids (except PG brine-based Al2O3–Ag nanofluid) seem to be not beneficial for practical use due to comparatively long payback period; however, that can be significantly reduced in future by decreasing nanoparticle cost and increasing nanofluid stability. The present study reveals that the brine-based hybrid nanofluids may be the potential option as next generation secondary refrigerants for low temperature applications.

Effect of different extenders for donkey sperm vitrification in straws.

Aseptic vitrification of semen samples packed in straws has been successfully developed in human but not in donkeys. The aim of this study was to compare the effect of two extenders for donkey sperm vitrification using straws. Ejaculates from four Andalusian donkeys were collected, and samples were extended in INRA-96 (I) or Gent (G) supplemented with sucrose 0.25M and 1% bovine serum albumin (BSA). Extended samples were cooled for one hour at 5°C. For vitrification, samples were filled in covered 0.25ml straws and then plunged directly into liquid nitrogen. For warming, straws were immersed in INRA-96 at 43°C. Results showed no significant differences between I and G treatments for TM (34.2%±8.7 vs. 30.7%±9.6) and PM (26.8%±7.3 vs. 24.6%±7.9), respectively. In conclusion, donkey sperm could be vitrified in straws either with INRA-96 or with Gent in combination with sucrose and BSA.

食品冷凍における進歩 : 特に水産物冷凍の研究と実際からみて(凍結及び乾燥研究会創立20周年記念講演「凍結及び乾燥技術の進歩と応用」)

食品冷凍における進歩 : 特に水産物冷凍の研究と実際からみて(凍結及び乾燥研究会創立20周年記念講演「凍結及び乾燥技術の進歩と応用」)

Lost Nutrition Differences Frozen Milkfish Non Whip Out Spines and Whip Out Spines During Low Storage

Freezing was one alternative way to maintain the quality of the fish. The purpose of this study was to determine the amount of nutrients lost from frozen fish drip non whip out spines and whip out spines on a long pull at different low storage temperatures of 2-5°C. The method used was experimental laboratory with the basic design of completely randomized design (CRD) with factorial pattern and repeated 3 times. Parameters measured were driploss test, the fat, water, protein and provitamin A content<br />in the drip, SEM (Scanning Electron Microscopy) analysis and organoleptic test. Data were analyzed using analysis of variance (ANOVA). The results showed that treatment of non whip out spines and whip out spines fish freezing and storage time gave a significant effect (P<0,05) on driploss; fat, moisture, protein,<br />provitamin A content in the drip; Morphological image test with SEM (Scanning Electron Microscopy) and organoleptic value. Driploss frozen fish of non whip out spines damaged 2 times greater than whip out spines, Value provitamin in the drip of non whip out spines frozen fish in the begunning of storage that was 185.28±9.85 µg/100g and in the endof storage was 257.23±17.00 µg/100g and organoleptic value of non whip out spines was 7.91±0.90 and whip out spines 7.53±1.06 in the end of storage.