The Feasibility of Using Agarophyte Processing Waste

When agarophytes are processed, 16-89% algal waste (AW) is formed. Due to the high content of minerals in this waste and the presence of proteins that are resistant to the action of proteolytic enzymes, such AW is mainly used in the production of feed for farm animals. The significant content of polysaccharides in dry AW indicates that it could be used as a raw material for the production of dietary fiber (DF). Due to the difference in the chemical composition of AW depending on the type of red algae, different approaches for its deproteinization have been used. Thus, a 3% alkali solution should be used for the deproteinization of algal waste from the red algae Gracilaria, a 0.5% alkali solution for GelidiumAW, and a 1% sodium carbonate solution for A. plicataAW.The duration of the deproteinization process is 30 min at a temperature of 97±2 ∘C for all types of AW. In this study, functional and technological solutions of DF from AW were developed. The results showed that their water binding capacity was 6-22 g of water per 1 g of the preparation, the fat binding capacity was 1.6-3.3 g of fat per 1 g of the preparation, and the swelling capacity was 46-312% depending on the type of red algae.The obtained DF was used in the production of minced fish food products of the ‘fish sticks’ type, based on minced fish and consisting of cod and pink salmon. The study of the chemical composition and calorie content of the developed food product showed the possibility of its use in dietary nutrition. Keywords: red algae, algal waste, deproteinization, dietary fiber

Development of recipes and technologies for the production of fish-growing products for baby food

В статье приводится краткий обзор инноваций по производству функциональных продуктов питания на основе рыбного сырья с целью установления современных тенденций их использования в детском питании. По данным статистики в России традиционно наблюдается дефицит потребляемого населением белка по причине однообразного, несбалансированного питания и низкой культуры потребления. Недостаток белка в организме неблагоприятно отражается на деятельности сердечно-сосудистой, дыхательной и нервной систем, как у детей, так и у взрослого населения. При производстве полуфабрикатов и кулинарных изделий из рыбы особую значимость приобретает совершенствование рецептур и технологий, направленных на повышение пищевой и биологической ценности, а также безопасности продуктов. Одним из способов повышения физиологической ценности белка животного происхождения является исследование по его биоусвояемости в детском организме, совершенствование органолептических показателей. К важнейшим свойствам продукции многие ученые относят доступность для различных социальных групп путем комбинирования рыбного фарша с различными растительными добавками. The article provides a brief overview of innovations in the production of functional food products based on fish raw materials in order to establish current trends in their use in children's nutrition. According to statistics, there is traditionally a shortage of protein consumed by the population in Russia, due to a monotonous, unbalanced diet, and a low consumption culture. The lack of protein in the body does not favorably affect the activity of the cardiovascular, respiratory and nervous systems, both in children and in adults. In the production of semi-finished products and culinary products from fish, the improvement of recipes and technologies aimed at increasing the nutritional and biological value, as well as the safety of products, is of particular importance. One of the ways to increase the physiological value of animal protein is research on its bioavailability in the child's body, improving organoleptic indicators. Among the most important properties of the products, many scientists refer to accessibility for different social groups by combining minced fish with various plant additives.

Development of technology and recipes for combined minced fish with food additives

The purpose of scientific research is to develop technologies and recipes for minced fish products with dietary supplements. The objects of research, when obtaining the recipe and technology of model minced fish, were: pollock, cod, wheat bread made from premium flour, and the dietary supplements introduced were oil extract of dried mushrooms, juniper oil extract, coriander oil extract and a complex additive "Moby Lux Universal". Vegetable oil extracts were used as a plasticizing component and additional raw materials containing flavoring substances. The use of additives of plant origin allows you to stabilize the functional and technological properties of raw materials, increase the biological value, emphasize the organoleptic characteristics of the finished product. Oil extracts of vegetable raw materials and "Moby-lux Universal" are rich in minerals and vitamins, dietary fibers, proteins, polyunsaturated fatty acids.

Anthocyanin Films in Freshness Assessment of Minced Fish

Introduction. Smart food packaging that alerts consumers to spoilt food by changing color is based on affordable and biodegradable raw materials. The research objective was to develop films from anionic polysaccharides and anthocyanin pigment that can be used as a freshness indicator of minced fish. Study objects and methods. The study featured frozen black currant berries (Ríbes nígrum), polysaccharide-based anthocyanin films, and minced fish. Extracts of anthocyanin pigment and films based on agar, kappa-carrageenan, chitosan, starch, and anthocyanin pigments were analyzed by IR spectroscopy. Results and its discussion. Anionic polysaccharides, i.e. agar and kappa-carrageenan, demonstrated good film-forming properties. Films based on 1.5% agar and 2% kappa-carrageenan showed elasticity, resilience, plasticity, and sufficient resistance to mechanical deformation. Neutral polysaccharide starch and cationic polysaccharide chitosan appeared to have no such qualities. An IR spectral analysis revealed chemical interactions between polysaccharide and anthocyanin molecules. It indicated the electrostatic nature of the polyelectrolyte complexes of the anthocyanin pigment with anionic polysaccharides. A film based on 1.5% agar fortified with anthocyanin pigment was used as a test-system for analyzing the quality of fish. The minced fish samples were wrapped in the anthocyanin film and left for 2–7 min to register the color change of the film. When the anthocyanin film came in contact with fresh fish, the color of the film did not change even after prolonged contact. When the film came into contact with spoilt fish, the color of the film began to change after 2 min of contact. When the contact time reached 7 min, the film turned blue. Conclusion. The type of polysaccharide and the interaction between polysaccharides and anthocyanin pigment had a significant effect on film formation. Anionic polysaccharides demonstrated the best results. Electrostatic interactions between anionic polysaccharides and anthocyanin pigments produced stable polyelectrolyte complexes. The new smart films were able to determine the quality of minced fish.

PENINGKATAN PERTUMBUHAN DAN SINTASAN BENIH IKAN TUNA SIRIP KUNING, Thunnus albacares DALAM PENDEDERAN SISTEM INDOOR

Sintasan larva hingga benih ikan tuna sirip kuning di hatchery sudah meningkat dari 0,05% menjadi 0,20%-0,50%. Namun mortalitas pada pemeliharaan tahap berikutnya sangat tinggi. Kematian benih karena menabrak dinding bak/jaring, berkaitan dengan kebiasaan renang dan kondisi lingkungan. Oleh karena itu, riset pendederan ini difokuskan pada pengamatan kebiasaan berenang dan pemangsaan, serta kondisi lingkungan. Wadah yang digunakan adalah enam buah bak fiberglass reinforced plastic (FRP) diameter 2,7 m; ketinggian 1,0 m; dan diisi dengan air laut 5 m3. Hewan uji berupa benih ikan tuna sirip kuning dengan panjang total 29,82 ± 2,51 mm hasil produksi dari hatchery, sebanyak 50 ekor benih per bak. Perlakuan dalam riset adalah perbedaan sistem pemeliharaan, yaitu: (A) indoor dan (B) outdoor dengan tiga ulangan dan lama penelitian 21 hari. Pakan yang digunakan adalah ikan segar berupa benih bandeng yang dimatikan dan ikan teri dengan panjang total 15-25 mm dan ikan cincang (minced fish). Frekuensi pemberian pakan adalah enam kali per hari dan diberikan secara satiasi. Parameter meliputi suhu, oksigen terlarut, dan intensitas cahaya diukur setiap hari. Hasil riset menunjukkan bahwa sintasan dalam pendederan sistem indoor sebesar 20,0 ± 4,0% lebih tinggi (P<0,05) dibanding dengan sistem outdoor (6,7 ± 5,0%). Pertumbuhan bobot spesifik 12,4% hari-1 pada sistem indoor lebih baik dibandingkan sistem outdoor yang hanya 9,8% hari-1 (P<0,05). Dari hasil penelitian ini dapat disimpulkan bahwa intensitas cahaya dan suhu yang lebih stabil pada pendederan sistem indoor memberikan sintasan dan pertumbuhan yang lebih baik dibandingkan pada sistem outdoor. Namun demikian, disarankan bahwa pendederan dalam bak FRP sebaiknya tidak lebih dari dua minggu agar diperoleh sintasan yang lebih tinggi dan selanjutnya dipindahkan ke karamba jaring apung (KJA).The survival rate of reared yellowfin tuna from larvae to juvenile stages in hatchery has been improved from 0.05% to 0.20%-0.50%. Unfortunately, the fish’s mortality rate during the nursery phase is still very high. Unpredicted swimming and feeding behaviors have resulted the reared juveniles to uncontrollably hit the tank wall and died. Therefore, this research was carried out to study the swimming and feeding habits of yellowfin tuna juveniles and its response to different rearing environments. Six fiberglass reinforced plastic (FRP) tanks with a diameter of 2.7 m, height 1.0 m, and filled with 5 m3 of filtered sea water were used in the study. Yellowfin tuna juveniles with an average total length of 29.82 ± 2.51 mm were harvested from a hatchery and placed into each tank at a density of 50 fish tank-1. The treatments applied were two nursery systems: (A) indoor and (B) outdoor system with three replicates. The rearing treatment lasted for 21 days. Raw fish was given as feed consisting of mixed of defrosted milkfish fry and small anchovy with total length ranged between 15-25 mm as well as minced fish meat. Feed was given six times per day at satiation. The observed parameters were temperature, dissolved oxygen, and light intensity measured daily. The results showed that the survival rate of juvenile in the indoor system was 20.0 ± 4.0%, which was higher (P<0.05) than that of the outdoor system (6.7 ± 5.0%). Weight specific growth rate of fish reared in the indoor system was 12.4% day-1 which was better than that of the outdoor system which was only 9.8% day-1 (P<0.05). This research concludes that a stable light intensity and water temperature in the indoor nursery system gives better survival and growth rate on yellowfin tuna juvenile. Nevertheless, this research recommends that the nursery phase of yellowfin tuna juvenile in FRP tank should be carried out not more than two weeks in order to produce a higher survival rate and then transferred to floating net cages.

Eryngium caeruleum essential oil as a promising natural additive: in vitro antioxidant properties and its effect on lipid oxidation of minced rainbow trout meat during storage at refrigeration temperature

Background: One of the most common species of oily fish is rainbow trout. Chemical deterioration of oily fish species is principally caused by lipid oxidation. The adverse effects of various chemical preservatives caused consumer’s attention to shift to natural alternatives. Eryngium caeruleum is an herbaceous plant that is native to the northern areas of Iran and is used in various local foods. The aim of the present study was to investigate the effects of different concentrations of E. caeruleum essential oil (EEO) on the physicochemical and oxidative stability of minced rainbow trout meat for 20 days storage at 4±1°C.Methods: Firstly, the chemical compounds and total phenolic content of EEO were determined by gas chromatography-mass spectrometry and Folin–Ciocalteu reagent, respectively. Then, in vitro antioxidant capacity of EEO was evaluated using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) methods. Finally, the minced rainbow trout meat was mixed with different concentrations of EEO, and physicochemical and oxidative stability of treatments were investigated for 20 days storage at 4±1°C.Results: According to the results, 0.4% EEO significantly improved the chemical stability of minced fish compared to the control group at the end of storage period with the following scores (P<0.05): pH value (6.3), peroxide value (11.88 meq/kg of lipid) and thiobarbituric acid reactive substance (0.43 mg MDA/kg sample).Conclusions: In order to increase the chemical quality characteristics of minced fish, new ingredient systems that are associated with natural and organic foods are applied. The results of present study indicate that the use of EEO in the meat industry can develop the novel healthy fish products and improve its chemical stability.Keywords: Eryngium caeruleum, Oncorhynchus mykiss, Natural antioxidant, Chemical stability, Lipid oxidation