scholarly journals Rainbow trout (Salmo irideus) produced in Finland III. Seasonal variations in rainbow trout

1967 ◽  
Vol 39 (3) ◽  
pp. 133-141
Author(s):  
Jorma J. Laine ◽  
Elina Varesmaa ◽  
Fritz P. Niinivaara
Keyword(s):  
Rainbow Trout ◽  
Chemical Composition ◽  
Seasonal Variations ◽  
Coliform Bacteria ◽  
Chemical Analyses ◽  
Organoleptic Quality ◽  
Microbiological Analyses ◽  
Growth Experiments

Seasonal variations in rainbow trout were studied in four geographically different places of growth. Experiments were carried out in May, July, September and February. The fish was weighed and tested for approximate chemical composition, total and coliform bacteria, and organoleptic quality. Besides chemical and microbiological analyses, tests were made from the cultivating waters. The results indicated that the fish varied according to the season and place of growth. In chemical analyses the greatest differences occurred in the amounts of water and fat. The organoleptic quality of trout seemed, however, to be mostly influenced by the places of growth.

Effect of Freeze-Drying and Cooking on Shrimp Quality

1970 ◽  
Vol 53 (5) ◽  
pp. 899-902 ◽  
Author(s):  
Barbara R Moorhouse ◽  
Harold Salwin
Keyword(s):  
Freeze Drying ◽  
Starting Material ◽  
White Shrimp ◽  
Chemical Analyses ◽  
Decomposition Products ◽  
Organoleptic Quality ◽  
Freeze Dried ◽  
Plate Counts ◽  
Crushed Ice

Abstract Approximately 500 pounds of white shrimp were stored in crushed ice until they decomposed. Portions were withdrawn at intervals and processed. Based on judgments of odor, shrimp that reached a stage of incipient decomposition before processing were rated as passable after they were freeze-dried or cooked. The organoleptic quality of samples that reached a stage of advanced decomposition was also improved by processing, but not to the extent of their being classified as passable. Aerobic plate counts increased during storage but they were reduced significantly by freezedrying or cooking. Although there were changes in composition during storage, the classical chemical tests used were of limited value for assessing the degree of decomposition. Also, many volatile decomposition products were lost during processing. Computing the results of chemical analyses on a moisturefree basis offered distinct advantages. Inasmuch as organoleptic, bacteriological, and chemical tests on the finished products failed to reveal the decomposed condition of the starting material, there is need for additional investigation of methods for that purpose.

scholarly journals Effect Of Age And Wholesale Cuts On The Quality Of Indigenous Sheep Carcass

1970 ◽  
Vol 37 (1) ◽  
pp. 32-38
Author(s):  
MA Hamid ◽  
S Akhter ◽  
SME Rahman ◽  
M Khan
Keyword(s):  
Chemical Composition ◽  
Crude Protein ◽  
Dry Matter ◽  
Phosphorus Content ◽  
Coliform Bacteria ◽  
Meat Sample ◽  
Ether Extract ◽  
Significant Difference ◽  
Total Bacteria

The study was conducted to investigate the nutritive value and microbial status of different wholesale cuts of sheep carcass. The meat sample was obtained from 3 sheep. The ages of sheep were approximately of 1, 2 and 3 years. The wholesale cuts were shoulder, rack, loin and leg of each sheep carcass. The pH, juiciness, chemical composition, total bacteria, coliform bacteria, yeast and mould were studied to assess the quality of meat. The range of pH value were 5.077 - 5.927. The value of juiciness was decreased with the age. The value of dry matter, ash, crude protein, ether extract, calcium and phosphorus content of all samples were ranged from 23.32-30.40%, 0.88-1.027%, 20.50-24.88%, 8.10-12.13%, 0.012-0.038% and 0.048-0.185% respectively. Statistical analysis indicated that the value of pH, juiciness, dry matter, crude protein, ether extract, calcium, phosphorus and yeast (log value) was highly significant (P< 0.01) due to age and cut. Chemical composition, such as dry matter, ash, ether extract and calcium of all the samples increased gradually with the age, except crude protein, which decreased gradually with the age. The phosphorus content of the sample did not differ significantly due to age and cuts. The value of ash content was less significant (P<0.05) due to different cuts but highly significant (P<0.01) due to age. The range of total bacteria and coliform bacteria was 4.210-4.787 and 2.38-3.637/g of sample respectively. The range of yeast was 1.297-2.777/g of sample. Different meat cuts and ages did not show significant difference on total bacteria and coliform bacteria but in case of yeast, the value was highly significant (P<0.01) for the ages and cuts. Nutrient content of mutton varies due to different wholesale cuts as well as age. DOI: http://dx.doi.org/10.3329/bjas.v37i1.9865 BJAS 2008; 37(1): 32-38

scholarly journals Comparison of chemical, microbiological and histological changes in fresh, frozen and double frozen rainbow trout (Oncorhynchus mykiss)

2014 ◽  
Vol 83 (2) ◽  
pp. 157-161 ◽  
Author(s):  
Peter Popelka ◽  
Jozef Nagy ◽  
Monika Pipová ◽  
Slavomír Marcinčák ◽  
Ľudovít Lenhardt
Keyword(s):  
Rainbow Trout ◽  
Chemical Composition ◽  
Oncorhynchus Mykiss ◽  
Structural Changes ◽  
Storage Temperature ◽  
Muscle Fibres ◽  
Total Volatile ◽  
Psychrotrophic Bacteria ◽  
Fresh Frozen

The final quality of fish meat depends on the chemical and microbiological quality of fish at the time of freezing as well as on other factors including storage temperature and freezing rate. Analysis of chemical composition (water, protein and fat content), expressible drip, total volatile nitrogen levels, microbiological analyses (total viable counts, Enterobacteriaceae, psychrotrophic bacteria) and histological examinations on dorsal skeletal muscles were carried out to distinguish fresh, frozen and double frozen rainbow trout (Oncorhynchus mykiss). Significantly higher expressible drip and total volatile base nitrogen concentrations (P < 0.05) were observed in frozen and double frozen trout, whereas chemical composition of fresh fish muscles was not significantly affected by freezing. The highest total viable counts, counts of Enterobacteriaceae and psychrotrophic bacteria were determined in double frozen trout. The light microscopy of fresh trout muscles did not show any microstructural changes, whereas deformations of muscle fibres and optically empty areas were found in frozen trout. Remarkable defects of the muscle structure in double frozen trout were demonstrated and total disruption of muscle fibres was found. The freezing of trout resulted in various structural changes in the dorsal skeletal musculature. This is a first study comparing changes in fresh, frozen and repeatedly frozen trout. Chemical, microbiological and subsequent histological examinations can be used for revealing the foul practices confusing the consumer with offering thawed fish instead of fresh cooled fish.

scholarly journals Rainbow trout (Salmo irideus) produced in Finland VII. Changes in the organoleptic quality and fetty acid composition during frozen storage

1969 ◽  
Vol 41 (3) ◽  
pp. 160-164
Author(s):  
Elina Varesmaa ◽  
Jorma J. Laine ◽  
F. P. Niinivaara
Keyword(s):  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Rainbow Trout ◽  
Acid Composition ◽  
Storage Time ◽  
Frozen Storage ◽  
Organoleptic Quality ◽  
Polyethylene Bags ◽  
Better Than

Rainbow trouts were frozen at –40° C and stored either glazed with water or vacuum packed in polyethylene bags at –18°and –32° C. During the storage time the quality of the fish was tested both organoleptically and by determining the fatty acid composition of the lipids. It was found that the fish were organoleptically uneatable after three months of storage. At –32° C the fish kept their organoleptic quality somewhat better than at –18° C. There were no important differences between the two packing systems used. The fatty acid analyses gave comparable results in all instances and probably changes in the proteins during frozen storage are more significant than changes in the lipids and are mostly responsible for the lowering in quality of frozen rainbow trout.

The microbiological quality of minced pork treated with garlic in combination with vacuum packaging

10.5219/1585 ◽  
2021 ◽  
Vol 15 ◽  
pp. 453-459
Author(s):  
Simona Kunová ◽  
Peter Haščík ◽  
Ľubomír Lopašovský ◽  
Miroslava Kačániová
Keyword(s):  
Microbiological Quality ◽  
Vacuum Packaging ◽  
Coliform Bacteria ◽  
Dilution Method ◽  
Microbial Quality ◽  
Pseudomonas Spp ◽  
Average Value ◽  
Garlic Oil ◽  
Microbiological Analyses

The present study aimed to evaluate the microbial quality of minced pork treated with fresh garlic, dried garlic, and garlic oil in combination with vacuum packing. The growth of Total Viable Counts (TVC), Coliform Bacteria (CB), and Pseudomonas spp. were evaluated. The microbiological analyses were performed by the plate dilution method. The average value of TVC was 8.45 log CFU.g-1 in aerobically packed samples, 5.59 log CFU.g-1 in samples treated with garlic oil, 5.36 log CFU.g-1 in vacuum packed samples, and samples treated with dried garlic, and 4.98 log CFU.g-1 in samples treated with fresh garlic on 8th day of storage. The number of TVC was significantly lower in samples treated with fresh garlic compared to samples treated with dried garlic and garlic oil on the 8th day of storage (p <0.05). The average value of CB was 4.13 log CFU.g-1 in aerobically packed samples, 1.82 log CFU.g-1 in samples treated with garlic oil, the value of CB in vacuum packed samples, in samples treated with fresh garlic and also with dried garlic was lower than 1.00 log CFU.g-1 on 8th day of storage. The number of CB was significantly higher in aerobically packed samples and samples treated with garlic oil compared to vacuum-packed samples, samples treated with fresh garlic and dried garlic on the 8th day of storage (p <0.05). The average number of Pseudomonas spp. was 2.45 in aerobically packed samples, count of Pseudomonas spp. was lower than 1.00 log CFU.g-1 in vacuum packed samples and in the sample with garlic on the 8th day of storage. The number of Pseudomonas spp. was significantly higher in aerobically packed samples in comparison with vacuum-packed samples, samples with fresh garlic, dried garlic, and garlic oil (p <0.05).

Prevalence of Listeria monocytogenes in, and Microbiological and Sensory Quality of, Rainbow Trout, White fish, and Vendace Roes from Finnish Retail Markets

2003 ◽  
Vol 66 (10) ◽  
pp. 1832-1839 ◽  
Author(s):  
HANNA MIETTINEN ◽  
ANNE ARVOLA ◽  
TIINA LUOMA ◽  
GUN WIRTANEN
Keyword(s):  
Rainbow Trout ◽  
Listeria Monocytogenes ◽  
Sensory Quality ◽  
Heterotrophic Bacteria ◽  
Microbiological Quality ◽  
Coliform Bacteria ◽  
Coregonus Lavaretus ◽  
Retail Markets ◽  
Sensory Qualities

The prevalence of Listeria monocytogenes in retail roe, as well as the microbiological and sensory qualities of the roe, were studied for three fish species under three different storage conditions. A total of 147 Finnish rainbow trout (Oncorhynchus mykiss), white fish (Coregonus lavaretus), vendace (Coregonus albula), and burbot (Lota lota) roe samples were bought fresh, frozen, or frozen-thawed from Finnish retail markets. The overall prevalence of L. monocytogenes was 5%; however, the prevalence of the pathogen in fresh roe was 18%. Fresh-bought roe tested positive for Listeria spp. and for L. monocytogenes, respectively, 5 and 20 times as often as did frozen and frozen-thawed roe products combined. The microbiological quality (analyzed as total aerobic heterotrophic bacteria and coliform bacteria) of 78% of the roe samples was unacceptable. Frozen roe samples were found to have the best microbiological quality. According to the results of a sensory evaluation, at least one sensory attribute (appearance, odor freshness, texture, and freshness of taste) was unacceptable for 29% of the roe samples studied. The sensory quality of roe samples bought fresh was better than that of roe samples bought frozen or frozen-thawed. From the results of this study, it is concluded that both the microbiological and the sensory qualities of roe at the retail level need to be improved.

scholarly journals Sensory analysis as a supporting method for marjoram breeding

2001 ◽  
Vol 7 (2) ◽  
Author(s):  
I. Novák ◽  
M. Héjja ◽  
H. Horváth ◽  
É. Héthelyi
Keyword(s):  
Chemical Composition ◽  
Essential Oil ◽  
Sensory Evaluation ◽  
Sensory Analysis ◽  
Suitable Method ◽  
Significant Differentiation ◽  
Organoleptic Quality ◽  
Sensory Tests

Marjoram is one of the most important spices in Hungary, which is utilized both in phytotherapy as well as in alimentary industry. Organoleptic quality of the drugs of two Hungarian varieties of Majorana hortensis /'Francia' and 'Magyar'/ were investigated by two different methods of sensory analysis. The chemical composition of the material was checked by GC analysis of the distilled essential oil. Although their main compounds and proportions showed similar patterns, both the human and instrumental sensory tests based on the complex odour and aroma of the drug, proved a significant differentiation of the two varieties. On the basis of our results, sensory evaluation may be a useful tool in the practice in determination of complex aromatic values of marjoram, as a spice. At the same time it seems to be a suitable method in promotion of breeding efforts.  

scholarly journals Effect of pesticide mixture on value of fresh, fermented and pickles cucumbers

2013 ◽  
Vol 54 (1) ◽  
pp. 191-207
Author(s):  
Krystyna WElkner ◽  
Jerzy Szwejda
Keyword(s):  
Chemical Composition ◽  
Fermentation Process ◽  
Quality Evaluation ◽  
Copper Hydroxide ◽  
Pesticide Mixture ◽  
Organoleptic Quality ◽  
Green Colour ◽  
Ascorbic Acids

In years 1998-1999 effects of fungicides (azoxystrobin and copper hydroxide), insecticides (etafenproks and pirimicarb) and their mixtures on chemical composition and organoleptic quality of fresh, fermented and pickled cucumbers were studied_ To analyses fruits were taken after 7 and 12 days from treatment. Fresh cucumber fruits after 7 days from treatment with investigated pesticides contained less carbohydrates and ascorbic acids and higher level of nitrates in compare to untreated fruits (control). After 12 days from treatment the differences between treated and untreated fruits dissapeared. Cucumber fruits harvested 7 and 12 days after treatment were processed separately. Quality evaluation of fermented and pickled cucumbers was carried out 4 months after processing. In most of cucumber fruits (7 days after treatment with pesticides) treated with pesticides empty cavities were found, and not in control (untreated). Number of cavities was highest in fresh and pickled cucumbers treated with mixture of fungicide and insecticide. In case of fermented cucumbers highest number of empty cavities occurred in fruits treated with fungicide azoxystrobin. Cucumber fruits taken to fermentation process 7 days after day of treatment had darker green colour, lowered haIdness, and larger empty cavities than untreated fruits. In fruits harvested 12 days after pesticides application such differencess were not observed.

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