Identification and measurement of fatty acids, amino acids in roe of tuna fish (Thunnus tonggol) and its TVB and peroxide value during cold storage

The first aim of this research was to identify fatty acids, amino acids composition of Thunnus tonggol roe and their changes during cold storage (-18'C). The second aim was to determine the changes of moisture, protein, fat and ash contents of the roe during one year cold storage (-18'C). 60 samples of longtail tuna (Thunnus tonggol) ovaries were randomly collected form Bandar-e-Abbas landings. The samples were frozen at-30'C and kept in cold store at -18'C for one year. According to a time table, the samples were examined for identification of fatty acids, amino acids, moisture, protein, fat, ash, peroxide and T.V.N. and their changes were evaluated during this time. The results showed that 26 fatty acids were identified. The unsaturated fatty acids (UFA) and saturated fatty acids (SFA) were 62.33 and 37.6%, respectively, in fresh roe. So that, DHA (C22:6) and oleic acid (C18:1) had high amounts (24.79 and 21.88%) among the UFA and palmitic acid (C16:0) was the most content (22.75%) among the SFA. The PUFA/SFA was 0.91. Also, 17 amino acids were identified that essential amino acids (EAA) and nonessential amino acids (NE) were 10478 and 7562 mg/100g, respectively, and E/NE was 1.38. Among the EAA and NE, lysine (2110mg/100g) and aspartic acid (1924 mg/100g) were the most contents. Also, results showed that moisture, ash, protein and fat contents were 72.74, 1.8, 19.88 and 4.53%, respectively, in fresh roe. The effects of freezing and cold storage on the roes showed that UFA and SFA contents have reached to 49.83 and 48.07%, respectively, at the end of cold storage. It indicated that these compounds change to each other during frozen storage. Also, n-3 and n-6 series of fatty acids were 32.75 and 1.61% in fresh roe. But their contents decreased to 22.96 and 1.25% at the end of period. Among the fatty acids, 22:6 and C16:0 had the most changes. The changes of fatty acids were significantly at 95% level except for C15:1, C18:3(n-3) and C20:4(n-6). All of the amino acids decreased in frozen storage and their changes were significantly (P<0.05). EAA was 7818 mg/100g and E/NE was 1.27 at the end of storage period. Among the amino acids, leucine and lysine had the most changes. Moisture, ash, protein and fat contents were 70.13, 1.82, 19.4 and 6.51%, respectively, at the end of storage period. The peroxide value and T.V.N. increased during storage. So that, their contents have reached to 5.86 mg/kg and 26.37 mg/100 g, respectively, at the end of frozen storage. The best shelf life of Thunnus tonggol roe was 6 or 7 months, because of lipid oxidation and increasing of peroxide.

Value-adding through coatings

The paper presents the three categories of food coatings that are used, individually or in combination, to produce battered or breaded foods. These are predust, batters and breadcrumbs. Predusts are usually a blend of flours, starches and other functional ingredients such as proteins, vegetable gums and seasonings or flavors; batters are blends of flours, starches, leavening agents and seasonings which, when mixed with water, forms a viscous liquid used to evenly coat a food item; while breadcrumbs are baked or otherwise thermally processed cereal-based ingredients which are applied to a moistened food item prior to cooking.

The value of mangroves

The article presents the forestry, fishery and ecological values of mangroves. Studies on the measurement of the economic value of mangroves that were conducted in Thailand, Indonesia and Ecuador are also presented.

The long road to freedom: the end of apartheid has signalled a new beginning for women in South Africa’s fisheries but real equality is still a far-off dream

Women in fishing communities are increasingly moving from traditional, community based occupations to seeking employment in the labour market. While this is an opportunity for women, their employment is also largely in the male dominated fishing industry, where job segregation into ‘less skilled and low paid’ jobs for women define employment opportunities. However, engagement as members in local non-government networks help women to challenge these stereotypes. In South Africa, for instance, the recent legislation promoting opportunity for women in male dominated sectors of employment is an opportunity for women to earn wages equal to those of men.

Economic value of the milkfish industry

A brief description is given of the milkfish (Chanos chanos) farming industry in the Philippines. Over the past 20 years, the relative importance of milkfish has declined with the expansion of tilapia, tiger shrimp and seaweed farming. In 1975, some 141,461 mt of milkfish made up 10% of the total fish production, whereas in 1995, the total milkfish harvest of 150,858 mt made up only 5.5% of the total fish production. Milkfish are harvested and marketed mostly fresh or chilled, whole or deboned, but some are canned or smoked. The domestic markets, mainly in Metro Manila, absorb most of the production. Milkfish is also absorbed in different product forms: dried, canned, smoked, or marinated. An export market for quick-frozen deboned milkfish fillets has begun to develop and fish processing companies are responding fast. The milkfish farming industry has important linkages with the various sectors that supply the inputs, and those that transport, store, market or process the harvest. For intensive milkfish farming to be both profitable and sustainable, more value-added products must be developed and marketed.

Market opportunity identification for minor crops for food security through value chain studies

The brochure is to contribute to the overall goal of stimulating the adaptation of pro-poor agri-food systems innovations to improve food security and sustainable natural resource management among rural poor farmers. The paper seeks to identify and exploit opportunities for expanding market access for minor crops and NRM products. The minor crops studied included cow pea, sorghum, groundnut, sweet potato and yam.

Nutritive value of fish of Lake Tanganyika [part] I: Amino acid composition

The amino acid composition was determined of three economic important fish species of Lake Tanganyika, representing 95% of the tolal catch:Stolothrissa tanganicae Regan, Limnothrissa miodon Boulenger and Luciolates stapersii Boulenger. The analysis of the whole sun dried fish indicate that, compared with Tilapia macrochir, beef and the whole hen's egg, the fish is of a very high nutritive value. The free amino acids in the dried fish count for an average of 11 %, indicating the degree of auteolysis.

Air traffic control with an expected value criterion

in this contribution we discuss a stochastic framework for air traffic conflict resolution. The conflict resolution task is posed as the problem of optimizing an expected value criterion. Optimization is carried out by Monte Carlo Markov Chain (MCMC) simulation. A numerical example illustrates the proposed strategy. Copyright © 2005 IFAC.

Nutritive value of fishes of Lake Tanganyika: II. Mineral composition

The composition of the minerals in three economically important fish species of Lake Tanganyika was determined. From the analyses there does not appear to be significant difference in the composition for the three species. Beside the major elements: Ca, P, K, Na, Mg, Cl, Fe, Al and Zn, eighteen trace elements were determined. The presence of the bones in the fish is especially nutritionally important for the following elements: Ca, P, Br, Sr, Mn and Mg.