Determination of some quality properties of marinated sea bream (Sparus Aurata L., 1758) during cold storage

In this study, it was aimed to determine the effect of sea bream (Sparus aurata) marinated some quality properties during cold storage. The fillets of fish were immersed into brine including 3.5% acetic acid 11% salt in the ratio of 1: 1.5 (fish: marinate brine) for marination process. After the process of ripening, samples were grouped into two and packed in plastic containers; one being plain (in sunflower oil) and the other being sauced (sauced prepared with sunflower oil). During storage, sensory, crude protein, lipid, dry matter and crude ash, TBA, TVB-N, TMA-N and peroxide analyses were done periodically. According to results of 200 days of storage, TVB-N values of sea bream marinates packaged as plain and sauced were 15.86/14.89 mg/100g, TBA 7.06/7.99 mg MA/kg, TMA-N 2.97/3.12, mg/100g, the value of peroxide was 7.23/7.45 meq/kg respectively. According to chemical and sensory analyses results obtained in the study; it was concluded that sea bream marinates packaged as plain and sauced can be stored in +4 °C for 200 days.

Quality changes during frozen storage of blue shrimp (Litopenaeus stylirostris) with antioxidant, α-tocopherol, under different conditions

Fresh blue shrimp (Litopenaeus stylirostris) muscle was stored with antioxidants under different conditions: ANTIOX 2%, packed in bilayer film of polyamide-low density polyethylene film (PA-LDPE) with 2% α-tocopherol; ANTIOX 4%, packed in PA-LDPE film with 4% α-tocopherol; and ANTIOX-GLAZED, samples stored glazed with 2% α-tocopherol. Shrimps packed in PA-LDPE without α-tocopherol were used as CONTROL. All samples were stored at –20 °C for 120 days. As compared to the CONTROL, the shrimp stored with the antioxidant showed lower lipid oxidation (0.10-0.14 vs 1.58 mgMA/kg of muscle), lost less firmness and astaxanthin content. ANTIOX 2% and ANTIOX-GLAZED showed the lowest concentrations of formaldehyde (0.081-0.083 μM/g). There were no significant differences in color and sensory properties, but differences in the integrity of the muscle fibers were observed. The treatments with α-tocopherol maintained the shrimp muscle quality during frozen storage. However, no significant differences were found between these treatments.

Addition of anacardic acid as antioxidants in broiler chicken mortadella

AbstractThe effect of anacardic acid on lipid stability and coloration of chicken mortadella was investigated. Antioxidants were added to chicken mortadellas, according to the treatments: no added antioxidant, 100 ppm butylated hydroxytoluene and 50, 100, 150 and 200 ppm anacardic acid. The mortadellas were stored for 90 days at 4 °C, and the analysis of lipid oxidation and color were performed. For TBARS, there was linear reduction with increased anacardic acid. According to the means test, 200 ppm anacardic acid provided the lower TBARS values. The redness decreased during storage, and, as reported by the means test, mortadella containing 200 ppm anacardic acid had lower values. The lightness of mortadellas decreased during storage. Also in accordance with the means test, mortadellas containing antioxidants had same lightness than control. The yellowness of mortadellas increased during storage. Thus, the anacardic acid is a potential natural antioxidant that could be included in chicken mortadella formulations before cooking.

Quality indicators and shelf life of red octopus (Octopus maya) in chilling storage

Abstract There are no precedents concerning the quality of Octopus maya during chilled storage. This study evaluated the shelf life of the red octopus in chilling storage (4oC) and the correlation of the sensory quality index with microbiological counting and the biochemical indicators (hypoxanthine, histamine and volatile amines). A total of 112 whole raw octopi (average weight of 896 g) were randomly selected from seven batches and exposed to 4°C for 18, 24, 48, 72, 84, 96, and 100 h. The histamine concentration (91.7%), followed by the counts of psychrotrophic bacteria (5.5%) and hypoxanthine (2.2%), were the predictors from the redundancy analysis that better explained the changes taking place during the chilling hours. After 72 h of chilling, the microbial count was determined to be log 4.7 CFU/g, and the octopus samples were classified as B quality (minor sensory quality defects) based on the sensory quality scale. Although the samples were not classified as unacceptable at 100 h of refrigeration by the sensory index, the level of histamine reached the defect action level (5 mg/100 g) as ruled by the International Food Safety Authorities. The shelf life of the red octopus in chilling storage was predicted to be 119 h.

Physicochemical characteristics and sensory acceptability of ready-to-eat sliced frozen roast beef with partial reduction of sodium chloride

Abstract Sodium chloride in meat products provides microbiological stability and desirable technological and sensory effects. Therefore, the reduction of this ingredient is a challenge for the meat industry. The objective of this study was to evaluate the physicochemical and sensory characteristics of ready-to-eat sliced frozen roast beef with partial replacement of sodium chloride by a commercial additive mostly composed of potassium chloride. The analyses performed were chemical composition, cooking yield and post defrosting loss, microbiological evaluation and sensory analysis. There was higher moisture content (p < 0.05) in the control treatment (without the presence of the replacement additive) and all treatments were not different (p ≥ 0.05) in the cooking yield and in post-defrosting loss. The results of microbiological analysis are according to Brazilian Legislation. The sensory evaluation showed no difference between the control treatment and the T1 treatment (with the reduction of 35% of NaCl), while the T2 treatment (with reduction of 70% of NaCl) had the lowest average values in all attributes. The study showed that the reduction of 35% NaCl for commercial additive, mostly composed of potassium chloride, in roast beef is feasible since no changes were observed in sensory and technological characteristics evaluated.

Variation of some chemical and functional properties of Bambara groundnut (Voandzeia Subterranean L. Thouars) during sort time storage

Abstract The storage susceptibility of Bambara groundnut (B. G.) (Voandzeia Subterranean (L.) Thouars) to Callosobruchus maculatus and chemical and functional properties of 11 varieties form Far-North of Cameroon were investigate using standard analytical methods. Storage susceptibility shown that, after five months within treatment, C. maculatus destroy 10 to 50% of grains. The chemical characteristics of none attack grains of 11 varieties were range to 18.64 at 21.08%, 6.85 at 7.44%, 49.75 at 52.68% and to 6.05 at 7.55% respectively for protein, fat, starch and free carbohydrate. These chemical characteristics significantly (p < 0.05) decreases form attacks varieties. For the functional parameters, the none attacks grains was range of 130 at 135%, 19.15 at 20.91%, 18.20 at 21.13%, 2.76 at 3.21% and of 8.54 at 10.14% respectively for water capacity absorption, solubility index, gel length, ash and humidity. The results of this study indicated that storage susceptibility, chemical and functional properties of B. G. be dependant to the varieties.

Variance reduction properties of dynamic hedging models - empirical evidence from BRICS countries

This Master’s Thesis analyses the effectiveness of different hedging models on BRICS (Brazil, Russia, India, China, and South Africa) countries. Hedging performance is examined by comparing two different dynamic hedging models to conventional OLS regression based model. The dynamic hedging models being employed are Constant Conditional Correlation (CCC) GARCH(1,1) and Dynamic Conditional Correlation (DCC) GARCH(1,1) with Student’s t-distribution. In order to capture the period of both Great Moderation and the latest financial crisis, the sample period extends from 2003 to 2014. To determine whether dynamic models outperform the conventional one, the reduction of portfolio variance for in-sample data with contemporaneous hedge ratios is first determined and then the holding period of the portfolios is extended to one and two days. In addition, the accuracy of hedge ratio forecasts is examined on the basis of out-of-sample variance reduction. The results are mixed and suggest that dynamic hedging models may not provide enough benefits to justify harder estimation and daily portfolio adjustment. In this sense, the results are consistent with the existing literature.

Eletrical conductivity and deterioration of soybean seeds exposed to different storage conditions

Research with soybean seeds has revealed that the results of the electrical conductivity test may be influenced by storage temperature, particularly low temperature, such as 10ºC, suggesting that seed deterioration at low storage temperatures does not seem to be directly related to the loss of the cell membrane integrity. This study was conducted with seeds of two soybean cultivars with the objective of: a) studying the effect of different storage temperatures (10ºC; 20ºC; 25ºC; 20/10ºC and 25/10ºC) on the results of the electrical conductivity test; b) observing the behavior of fatty acids and carbohydrates during storage and studying its relation with the electrical conductivity results. Every three months, from a total of 18 months of storage, the physiological quality of seeds was evaluated using the germination, accelerated aging and electrical conductivity tests. Based on the obtained results, it can be concluded that the electrical conductivity test was not shown to be a good indicative of the deterioration process of seeds stored at low temperatures, and no direct relationship between changes in the fatty acids and carbohydrates and the behavior of the mentioned test for seeds stored at 10ºC was found.

Tolerance level of green seed in soybean seed lots after storage

The occurrence of green soybean seed due to forced maturation or premature plant death caused by drought or foliar and/or root diseases has been common in several Brazilian production areas. Physiological quality of seed lots with green seed may have their germination and vigor potentials affected and therefore discarded by the grain industry. The objective of this experiment was to determine the maximum tolerated level of green seed in soybean seed lots, which is information of major importance for seed producers when taking the decision whether to sell these lots. Soybean seed of the cultivars CD 206, produced in Ubirata, Parana, and ‘FMT Tucunare,’ produced in Alto Garças, Mato Grosso, were used in the study. Green seed and yellow seed of both cultivars were mixed in the following proportions: 0%, 3%, 6%, 9%, 12%, 15%, 20%, 30%, 40%, 50%, 75% and 100%. Seed quality was evaluated by the germination, accelerated aging, tetrazolium and electrical conductivity tests. The contents of a, b and total chlorophyll in the seed were also determined. A complete randomized block design in a factorial scheme (two cultivars x 12 levels of green seed) was used. Seed quality was negatively affected and chlorophyll contents incremented with the increase in the percentage of green seed. Seed germination, viability and vigor, measured by the accelerated aging test, were not reduced with levels of up to 3% green seed, for both cultivars. Levels above 6% green seed significantly reduced the quality of the seed. The quality of seed lots with 9% or more green seed was significantly reduced to the point that their commercialization is not recommended.

Physiological and enzymatic alterations in papaya seed during storage

This study was done to evaluate the physiological and enzymatic alterations in papaya (Carica papaya L.) seeds during storage period. Seeds were extracted from mature fruits of Formosa group papaya hybrid Tainung 01. The sarcotesta was removed by rubbing the seeds on a wire screen under running water and then dried to the moisture content (MC) of 5, 8 or 11% The seeds were packed in multilayer paper bags, polyethylene bags, aluminum foil pouch and metallic canisters and stored for 15 months under laboratory conditions. Seeds were evaluated, at three month interval, for MC, germination, and the activity of acid phosphotase (AP) and malate dehyrogenase (MDH) was evaluated with the use of amide gel (12%) electrophoresis. The fresh seeds had post-harvest dormancy, which was broken after six month storage. Independent of the package type, the seeds could be stored for 12 months with 8 or 11% MC under ambient conditions. There was no association between seed deterioration and alterations in AP and MDH activity.

Effect of storage period on isoflavone content and physiological quality of conventional and transgenic soybean seeds

The objective in this research was to evaluate the isoflavone content and the physiological quality of seed from conventional and transgenic soybean cultivars before and after 180 days of storage. Twenty one soybean cultivars: CD 202, CD 206, CD 208, CD 213RR, CD 214RR, CD 215, CD 216, CD 217, CD 218, CD 221, BRS 184, BRS 185, BRS 214, BRS 244RR, BRS 245RR, BRS 246RR, BRS 255, BRS 257, BRS 258, BRS 261 and BRS 262, grown in the 2005/2006 crop season, were assayed. The seeds were packed in Kraft paper bags and stored at room temperature under laboratory conditions. Seeds were evaluated with respect to their germination and vigor (first germination count, accelerated aging and tetrazolium test) and their total isoflavone contents and respective aglycon forms (daidzein, genistein and glycitein),glycosides (daidzine, genistine and glycitine) and malonyl conjugates. A completely randomized block design with six replications with the treatments set out within a subplot scheme (21 cultivars x 2 storage periods) was used. The F-test was used to compare means between storage periods and the Scott-Knott test to compare cultivars for each storage period, both with a 95% probability. It was concluded that isoflavone contents differ between cultivars and show a distinct behavior throughout storage.

Storage of 'Swingle' citrumelo seeds in different maturation stages subjected to fungicide treatment

The establishment of citrus orchards with rootstocks from seed with a low physiological quality has been a recurring problem. Low quality seeds directly affect both the final stand and the time required for seedling production. The irregular maturation of fruits, seed recalcitrance, and the high incidence of fungi, make long term storage difficult, even at low temperatures. This study evaluated the storage potential and the use of fungicide treatments on 'Swingle' citrumelo seeds extracted from fruits collected at two maturation stages, green or ripe. The seeds were subjected to a thermal treatment, treated with Derosal, Thiram or Tecto+Captan fungicides, packaged in impermeable polyethylene bags and stored in a cold chamber for nine months. Every three months, the physiological and sanitary qualities of the seeds were evaluated from germination and sanitary tests and also from enzyme profiles. Seeds from green fruits deteriorated less than those from mature fruits; deterioration increased up to nine months of storage; treatment with the Tecto+Captan mixture gave effective pathogen control and maintained seed quality during storage. The germination of the green and ripe seeds is satisfactory (70%) after three months storage.

Adhesion of uredospores of Phakopsora pachyrhizi on soybean seeds and their viability during storage

To study adhesion and viability of uredospores of the fungus Phakopsora pachyrhizi on soybean seeds during storage, suspension tests of those uredospores were carried out by washing seeds at each 30 days interval. Furthermore, germination and inoculation tests of uredospores on soybean plants were performed with uredospores collected from seeds of two soybean production areas, located in the municipalities "Chapada dos Guimarães" and "Tangará da Serra", State of Mato Grosso, Brazil. High levels of uredospores infestation were detected before storage [249.31 and 85.18 uredospores/100 seeds (U/100)] on seeds collected in both localities, respectively. After 30 days storage, these figures were 46.12 and 122.5 U/100; at 60 days were 14.62 and 26.62 U/100; and at 90 days were only 2.87 and 3,68 U/100, respectively; dropping to zero after 120 days storage. The percentage of germinated uredospores decreased with increasing storage periods and at 120 days germination percentage was nil. When uredospores were inoculated on soybean plants, rust symptoms were only observed for uredospores collected from freshly harvested seeds. Uredospores associated to soybean seed germinate until 90 days after storage, but are not viable after this time span. Infection of plants only occurs with inoculation of uredospores obtained from freshly harvested seeds.

Accelerated aging of ipê seeds under controlled conditions of storage

This research was aimed at studying effects of storage and accelerated aging on germination and profile of storage proteins in Handroanthus albus seeds. These were stored into a cold chamber (± 8 ºC; RH ± 40%) and after periods of 0, 3, 6, 9, and 12 months of storage, were subjected to accelerated aging for 0, 24, 48, 72, and 96 hours. Relationships between germination and proteins profile were assessed. Germination test was performed at 25 ºC, under constant light. For protein extraction, 125 mg of seeds were macerated in 2 mL of extraction buffer (1M Tris-HCl; pH 8.8) and applied to SDS-PAGE polyacrylamide gel at 80 V .15 h-1. Twelve month storage, combined with 72 hours accelerated aging have increased germination in approximately 65% when compared to non-aged seeds or to seeds with 24 h of accelerated aging. Besides beneficial effects, degradation and synthesis of different proteins were observed. It was concluded that germination of Handroanthus albus seeds, when not subjected to accelerated aging, is favored by storage in cold chamber during three to six months, or from nine to 12 months when subjected to accelerated aging process. Storage proteins may be associated to those increases, and hence further studies are needed.

Survey, survival and control of Alternaria alternata in wheat seeds

The fungus Alternaria alternata was quantified in 75 wheat seed samples collected from three different regions of southern Brazil for Cropping and Use Value (CUV) I, II and III. Fungal presence was evaluated in two hundred disinfested seeds per sample before sowing in a potato-dextrose-agar medium + antibiotic (PDA+A). Fungus survival was evaluated every 45 days for 180 days for three seed batches from six wheat cultivars stored in propylene bags in a storehouse, with air temperature varying between 18 to 22 °C and relative air humidity around 60%. The efficacy of carboxin+thiram, difenoconazol, thiram, triadimenol, triticonazol and triticonazol + iprodione fungicides to control A. alternata was determined. A. alternata was detected in all the samples with an incidences of 39.6 %, 38.8% and 35.9% for the CUV I, CUV II and CUV III regions, respectively. The highest mean incidence of the fungus was found in the CUV I region, the coolest and most humid, and was significantly different from the other two regions. The average reduction in A. alternata viability in the wheat cultivar seeds was 49.5% during the 180 days of storage (inter-harvest period), demonstrating that infected seeds are the primary inoculum source for the fungus. The triticonazol + iprodione fungicide mixture efficiently controls A. alternata.