THE SPECTROPHOTOMETRIC ANALYSIS OF ANTIOXIDANT PROPERTIES OF SELECTED HERBS IN VISION-PRO™ UV-VIS

The aim of the study was to evaluate the influence of type of the solvent (water, aqueous ethanol and ethanol) on the antioxidant properties of four various herbs: couch grass (A. repens), milk thistle (S. marianum), dandelion (T. officinale) and fireweed (E. angustifolium) measurement by three common UV-VIS methods (TPC, ABTS+, DPPH). The results were collected through the Vision-Pro™ UV-VIS spectrophotometer software. Aqueous ethanol was the most effective solvent for extraction for all type of herbs. Fireweed contains the highest amount of polyphenol compounds (0.625 µg GA/ml). The lowest antioxidant capacity was presented by extracts from couch grass (0.019 µg GA/ml)

INSTRUMENTAL COLOR MEASUREMENT OF MEAT AND MEAT PRODUCTS IN X-RITECOLOR® MASTER

The aim of the study was to evaluate the influence of lyophilized plant extract on color of canned meat with reduced amount of sodium (III) nitrite measured by spectrophotometric methods. The results were collected through the X-RiteColor® Master software. The results of the experiment show that reduction of nitrite salt is possible but additional fortification is required: the best results were obtained when the extract was added in the amount of 0.015%

The Possibility of Reduction of Synthetic Preservative E 250 in Canned Pork

The purpose of this study was to determine the possibility of reducing the amount of NaNO2 added to canned pork during 180 days of storage. In this study, three variants of canned pork were prepared by adding different amounts of sodium nitrite: N (100 mg/kg), NH (50 mg/kg), and NF (no nitrite). The antioxidant capacity, amount of secondary products of lipid oxidation, color intensity, and pH were analyzed after one, 60, 90, and 180 days of storage where sensory properties, water activity (aw), selected pathogenic bacteria, nitrate and nitrite residues, N-nitrosamines (NA), and cholesterol were analyzed after 1 and 180 days of storage. The redness parameter of the nitrite-free canned meat was found to be significantly lower (about 6.4) than that of the products containing sodium nitrite (N: 10.49 and NH: 9.89). During the storage period C. perfringens, L. monocytogenes, and Salmonella were detected in the products. It is not possible to completely eliminate nitrite from the canned pork production process without deteriorating the color, antioxidant properties, sensory characteristics, and health safety. However, the level of hazard chemicals such as NA, nitrate and nitrite residues can be limited by decreasing the amount of nitrite addition to 50 mg/kg. The free-radical scavenging ability for the sample with 50 mg/kg of sodium nitrite was observed to be poor, so its fortification with plant material rich in various polyphenolic substances may be necessary

Porównanie metod dyskretyzacji danych w uczeniu modeli probabilistycznych

Very often statistical method or machine learning algorithms can handle discrete attributes only. And that is why discretization of numerical data is an important part of the pre–processing. This paper presents the results of the problem of data discretization in learning quantitative part of probabilistic models. Four data sets taken from UCI Machine Learning Repository were used to learn the quantitative part of the Bayesian networks. The continuous variables were discretized using two supervised and two unsupervised discretization methods. The main goal of this paper was to study whether method of data discretization in given data set has an influence on model’s reliability. The accuracy was defined as the percentage of correctly classified records.Bardzo często algorytmy uczenia maszynowego nie są przystosowane do korzystania ze zmiennych ciągłych. Z tego powodu dyskretyzacja danych jest istotną częścią wstępnego przetwarzania. W artykule przedstawiono wyniki prac nad problemem dyskretyzacji danych w uczeniu modeli probabilistycznych. Cztery zestawy danych pobrane z repozytorium uczenia maszynowego UCI zostały wykorzystane do nauczenia parametrów ilościowej części sieci bayesowskich. Występujące w wybranych zbiorach zmienne ciągłe były dyskretyzowane przy użyciu dwóch metod nadzorowanych i dwóch nienadzorowanych. Głównym celem tego artykułu było zbadanie, czy metoda dyskretyzacji danych w danym zbiorze ma wpływ na niezawodność modelu. Dokładność metod była definiowana jako odsetek poprawnie sklasyfikowanych rekordów

Reduction of Nitrite in Meat Products through the Application of Various Plant-Based Ingredients

Nitrite is the most commonly applied curing agent in the meat industry, and is known to affect human health. Nitrites impart a better flavor, taste and aroma; preserve the red-pinkish color of the meat; and prevent the risk of bacterial contamination of the cured meat, especially from Clostridium botulinum. Unfortunately, recent research has demonstrated some negative effects of this technique. Certain N-nitroso compounds have been shown to stimulate gastric cancer; therefore, most of the research groups are studying the effects of nitrates and nitrites. In this review, we discuss the various food sources of nitrites and nitrates and their current legal requirements for use in meat products. We also discuss the possible changes that might come up in the regulations, the concerns associated with nitrates and nitrites in meat products, and the use of plant-based nitrite and nitrate substitutes. All these topics will be considered with respect to ensuring a high level of microbiological protection, oxidative stability and acceptable sensory quality (color, taste and smell) in meat products

Influence of Sonication and Taraxacum Officinale Addition on the Antioxidant and Anti-ACE Activity of Protein Extracts from Sous Vide Beef Marinated with Sour Milk and after In Vitro Digestion

The present study assessed the effect of pretreating beef as a raw material for sous vide steak preparation. The pretreatment involved maceration of a batch of meat in sour milk with the simultaneous use of ultrasound (250 or 500 W) as well as the addition of Taraxacum officinale. The biological activity profile of the peptides was assessed in terms of their antioxidant activity and inhibiting activity against angiotensin-converting enzyme (ACE). Changes in the biological activity of peptides under the influence of hydrolysis by gastrointestinal enzymes, i.e., pepsin and pancreatin, were also considered. There was no significant effect of T. officinale addition and sonication of beef batches on the protein content (except for lot S6, after sonication at 500 W as acoustic power and with the addition of dandelion). It was observed that the interaction of maceration in sour milk with simultaneous ultrasound treatment as the initial production step of sous vide beef steak generates the formation of peptides with antioxidant properties. Moreover, peptide formation can be further enhanced by adding dandelion (based on the results of antiradical and chelating activity tests). In addition, the progression of hydrolysis under the influence of gastrointestinal enzymes promotes the release of peptides with antioxidant and anti-ACE activity