FISH FEED MICROBIOLOGICAL STATUS

Abstract Lack of domestic fish feed products results with the need of import. However, fish feed may trigger changes in the fish metabolism. Namely, the feed may be responsible for the decrease in fish accretion and/or the reason for the fish diseases occurrence. All these problems commonly are connected with feed and/or water quality. Therefore, we decided to investigate the microbiological status of various feeds used in fish diet. In this research we investigated following groups of microorganisms in fish feed: Total number of bacteria, sporogenous bacteria, yeasts and molds, coliforms, Escherichia coli and Proteus species, as well as fecal streptococci and staphylococci and sulfitoreductive clostridia. The results showed that the feed used in the fish diet, nevertheless is domestic or imported, largely differs in their microbiological status, regardless we are speaking for quality or safety. Fish feed from domestic origin showed high contamination rates, and this directly resulted in fish growth rate decrease, and demonstrated toxic effects, because one of the finds was presence of aflatoxin producers

Usage of Biologics on Tomatoes and Peppers

In fruit growing, nowadays a lot of chemical products are used (insecticide, fungicide etc.) in order to protect the plants. However, lately the markets are in need of gardening products which are not treated with pesticide but protected with biologics. In gardening, biological fight against the insects and the diseases is not much maintained because the shares are lower and the gardening products are on a great demand and are very profitable. Due to the great profit of the gardening products, less attention is paid to the biological fight for protection. However, the great environmental pollution evokes great interest in consuming healthy gardening products. Due to the mentioned reasons, lately, fruit producers show interest for usage of biologics to protect the gardening products from some insects and diseases. There appear to be many biologics but the producers of gardening products are not well informed because the interest of usage of biologics is not high. By all means, the market provides verified biologics which show good production results. The great interest in usage of biologics to protect the gardening products from diseases and insects increases, whereas the interest of research institutions to discover better biologics is getting bigger

Biosynthesis of pectinolytic enzymes by Aspergillus on apple pulp

The aim of this work was to develop a low cost process for apple pulp utilization. The apple pulp combined with corn flour and simple mineral salts by submerged production of pectinolytic enzymes by the fungus Aspergillus. Different concentration on apple pulp and different pH initial on the bases were studied, and all other process parameters were same. Results of different concentration on apple pulp gived maximal endo- PG with 1% apple pulp, during from 96 h, and the growth of the microorganism showed maximum dry weight on initial pH on bases- 4, during from 48 h. From results can be see that the apple pulp can be used as inexpensive base for industrial production on pectinolytic enzymes by Aspergillus

The effect of pectolytic enzyme treatments on white grape mashes of Smederevka on the microbiological quality of wines

The paper investigates effects of pectolytic enzyme treatments on white grape mashes on the microbiological quality of wines and wine stability with counting of the presence yeast cells (Saccharomyces cerevisiae), after incubation on Sabourald-maltose agar. Also wine samples were investigates of the presence moulds and other bacteria, as and dangerous bacteria Salmonella and Shigella, Staphylococus aureus, Proteus spp., Sulphite-reducing clostridy and Escherichia coli.In all wine samples the results showed that have yeasts Saccharomyces cerevisiae. Saccharomyces is not regard as spoilage organism only if it is found in the wrong place at the wrong time (e.g. in a bottle of semi-sweet wine) causing re-fermentation, meanwhile the better is to have less. Pectinolytic enzyme preparation Trenolin Mash DF showed the best results

Risks of microbial spoilage of wine: a review

Wines are alcoholic drinks obtained from the fermentation of grapes. The main role of microorganisms in winemaking is to convert grape sugars to alcohol, reduce wine acidity and contribute to aroma and flavor. They can also cause numerous unwelcome wine spoilage problems, which reduce wine quality and value. Winemaking processes includes multiple stages at which microbial spoilage is likely to occur and ends up with altering the quality and hygienic status of the wine. This may render the wine unacceptable, since the spoilage can include bitterness and off-flavours, and cosmetic problems such as turbidity, viscosity, sediment and film formation. The main microorganisms associated with wine spoilage are yeasts, acetic acid bacteria and lactic acid bacteria. A microbial spoilage is the consequence of inadequate working practices. These inadequate practices are derived from two principle attitudes: (1) - non-application of known practices for well identified risks and (2) - insufficient evaluation of risk levels. One of the aims of winemaking is to minimize potential for microbial spoilage and in this review are presented risks of microbial spoilage of wine and their prevention

Comparison of effects of three commercial pectolytic enzyme preparations in white winemaking

White grape mashes of Smederevka were treated with different pectolytic enzyme preparations. These treatments resulted in increases in clarity of the wine, filterability, amounts of solids that settled and wine quality. The results of the experiments provide comparison of the efficiency of preparations applicable in white winemaking. The time of filtration was two times shorter when using the enzyme preparations Trenolin Mash DF and Rohavin LX compared to the control sample. By using the enzyme preparations Vinozym Process, the speed of desliming was threefold faster, and in the case of Trenolin Mash and Rohavin LX twofold faster compared to the control sample. These enzyme treatments resulted in clarified the white grape juice, degraded the grape mash, reduced juice viscosity and elicited an improvement in the visual aspect of the wine

Effects of pectolytic enzyme treatments on white grape mashs of Smederevka on grape juice yields and volume of lees

The aim of this work was to evaluate the effect of the use of pectolytic enzyme treatments on white grape mashs of Smederevka on grape juice yields and volume of lees. White grape mash from Smederevka were macerated for 4 hours at 18 to 20oC with addition on one commercial pectolytic enzyme preparation (Vinozym Process, Trenolin Mash DF, Rohavin LX). After maceration, the pomace was removed, and each musts are pour into the funnel and collect musts. Results of trials showed increased on free run juice yields by 7,12% and drastic reduction in the volume of gross lees by up 47,3% compared with control trials. Increase juice yields and reduction volume of gross lees, leading to a higher volume of clear must, and this in the more produced wine and on end the more profit

Effecs of pectolytic enzyme treatments on white grape mashes of Smederevka on polyphenolic content of wines

The aim of this work was to study the effect of the use of pectolytic enzymes on the phenolic composition of young white wines made of white grape Smederevka (V. vinifera L.). White grape mash from Smederevka were macerated for 4 hours at 18 to 20 oC with addition on one commercial pectolytic enzyme preparation (Vinozym Process, Trenolin Mash DF, Rohavin LX). The obtained results of laboratory trials showed decreased concentration of total phenolics by 37.8% and results of industry trials decreased by 39.2%. These enzyme treatments resulted in clarified the white grape juice, degraded the grape mash, reduced juice viscosity and total phenols and elicited an improvement in the visual aspect of the wine

Effect of enzyme preparation treatments on the chromatic characteristics of red wines from Vranec

The aim of this work was to study the effect of the use of pectolytic enzymes in the chromatic characteristics of young red wines. Laboratory trials were carried out, using three different commercial preparations of pectolytic enzymes (Vinozym Vintage FCE, Rohavin CXL, Trenolin Super DF) with four doses and industrial trial using one commercial preparation of pectolytic enzymes (Vinozym Vintage FCE) along with controls with no added enzyme. The obtained results of laboratory trials showed increased of colour intensity (CI) from 2.5 to 19.0 % and industry trial by 23 % depend of used doses, compared to the control samples. The pectolytic enzyme treatments showed improvement in the visual aspect of the wine

RISKS OF MICROBIAL SPOILAGE OF WINE: A REVIEW

Abstract Wines are alcoholic drinks obtained from the fermentation of grapes. The main role of microorganisms in winemaking is to convert grape sugars to alcohol, reduce wine acidity and contribute to aroma and fl avour. They can also cause numerous unwelcome wine spoilage problems, which reduce wine quality and value. Winemaking processes include multiple stages at which microbial spoilage is likely to occur and ends up with altering the quality and hygienic status of the wine. This may render the wine unacceptable, since the spoilage can include bitterness and off -fl avours, and cosmetic problems such as turbidity, viscosity, sediment and fi lm formation. The main microorganisms associated with wine spoilage are yeasts, acetic acid bacteria and lactic acid bacteria. A microbial spoilage is the consequence of inadequate working practices. These inadequate practices are derived from two principle attitudes: (1) nonapplication of known practices for well identifi ed risks and (2) insuffi cient evaluation of risk levels. One of the aims of winemaking is to minimize potential for microbial spoilage and in this review are presented risks of microbial spoilage of wine and their prevention