Technologia Alimentaria (Technologia Żywności i Żywienia) 7 (4) 2008
Abstracts
Title
EFFECT OF PRE-FREEZING AND CULINARY TREATMENT ON THE CONTENT OF AMINO ACIDS OF GREEN PEA
Autor
Piotr Gębczyński, Waldemar Kmiecik, Zofia Lisiewska, Jacek Słupski
Pages
5–14
Keywords
green pea, blanching, cooking, freezing, microwave thawing and heating
Abstract
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Green pea is regarded as an important constituent of a human diet, especially for vegetarians. The aim of the present work was to evaluate the amino acids content in green pea and the quality of pea protein. The study covered raw seeds; fresh seeds cooked to consumption consistency; and two kinds of frozen products prepared for consumption: frozen seeds obtained using the traditional method and frozen seeds of the ready-to-eat type. Compared with the raw material, cooked fresh pea contained more isoleucine (15%), valine (14%) and arginine (24%) but less tyrosine (17%); cooked pea from the traditional frozen product contained less sulphur-containing amino acids (12%) and alanine (13%); while pea from the frozen product of the ready-to-eat type contained a similar or higher amount (from 12% to 38%) of amino acids, except for sulphur-containing amino acids (less 12%). The protein of green pea was of very good quality, both in raw seeds and in those prepared for consumption. In comparison with the FAO/WHO/1991 standard, the CS indexes exceeded 100. It was only for sulphuric amino acids that the CS for the ready-to-eat product was 98. The methods of culinary and technological processing applied affected the quality of protein in green pea seeds to a negligible degree.
PHYSICO-CHEMICAL PROPERTIES AND ANTIOXIDANT ACTIVITY OF SELECTED PLUM CULTIVARS FRUIT
Autor
Julita Reguła, Dorota Walkowiak-Tomczak, Grzegorz Łysiak
Pages
15–22
Keywords
plum, antioxidant activity, colour, physical and quality parameters
Abstract
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The aim of the study was to present and compare characteristics of pomological parameters, colour, dry matter and solids contents, as well as antioxidant activity of fruit of selected plum cultivars. Analyses were conducted on plums (Prunus domestica) of three cultivars: ‘Węgierka Zwykła’, ‘Bluefre’ and ‘Elena’. Presented morphological parameters of fruit and stones included their length, width and weight, as well as mean fruit size and firmness. Fruit colour was measured by spectrophotometry in the L*a*b* system. Contents of dry matter and solids were determined in fruits. Moreover, Trolox-equivalent antioxidant capacity (TEAC) of plums was assayed by colorimetry using a cation radical ABTS. The biggest fruits were found for cv. ‘Bluefre’, while the highest value of dry matter and solids contents – in cv. ‘Węgierka Zwykła’. Higher antioxidant activity (µM Trolox/g d.m.) was assayed in plums of relatively new cultivars, ‘Bluefre’ and ‘Elena’, in comparison to the traditional cultivar ‘Węgierka Zwykła’.
TECHNOLOGICAL QUALITY OF GRAIN OF SPRING WHEAT CULTIVATED AS PURE VARIETIES AND THEIR MIXTURES
Autor
Zygmunt Gil, Mirosław Żmijewski
Pages
23–30
Keywords
wheat, grain, variety mixtures, milling mixtures
Abstract
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Technological quality of grain and flour of milling mixtures ‘Omega’ + ’Igna’ + ’Henika’ and ‘Omega’ + ’Igna’ + ’Banti’, made of three varieties of grain mixed in equal proportion were compared to quality of wheat which was cultivated in mixtures of the same varieties. Before sowing those varieties were compiled in equal proportion. ‘Omega’ and ‘Igna’ are varieties susceptible to infestation by fungi unlike ‘Henika’ and ‘Banti’ varieties. Wheat was cultivated with or without fungicide protection. Hectolitre weight, content of low molecular SDS-soluble protein and number of insoluble protein in flour were more profitable for mixtures made of pure stands than variety mixtures. As far as vitreousness of grain, milling properties of grain, content of protein in grain and SDS + ME-soluble protein are concerned the quality of variety mixtures was higher for the variety mixture in comparison with mixtures made of pure stands. Fungicide protection in the cultivation of pure varieties and varieties mixtures increased value of hectolitre weight and filling and uniformity of grain.
Usefulness of analytical method (bromocresole purple index – BCPI) as a new and fast way for available lysine (LA) content determination in micro-waved soybean seeds was tested. Due to a great interdependence of LA and BCPI determinations, which was confirmed by high correlation and determination coefficients values (r = 0.78 and R2) for proposed regression equations LA = f(BCPI), the BCPI method appeared to be useful for the description of available lysine (LA) content changes in micro-waved soybean seeds and soybean meal.
The growing popularity of functional foods causes increasing interest in raw materials, which can raise the pro-health value of food when supplemented. The aim of the study was to assess the effect of compounds with antioxidant properties on Lactobacilluscasei, as a representative of probiotic microorganisms. In the experiments the pure antioxidants and plant extracts were used. The results showed that catechin at concentration of 100-400 μM and chlorogenic acid (400 μM) had a stimulatory effect on L. casei growth. Quercetin at concentrations of 25-50 μM showed an inhibitory effect when incubation time was ≥ 6 h. The lingonberry leaves extract caused a slight increase in the dry substance of biomass in comparison with control. Extracts of coffee, chokeberry, and dog rose should not be used as additives for probiotic food as they significantly inhibited L. casei. We conclude that: 1) antioxidants at concentrations higher than 100 μM may stimulate growth of L. casei; 2) except the antioxidants, some other compounds which are present in plants extracts e.g. tannins and alkaloids may exert an antibacterial influence; 3) the probiotic yoghurts supplementation with fruit and other plant materials should be preceded by careful studies about their influence on the bacteria.
USING THE BIOLUMINESCENCE AND MICROBIOLOGICAL CONTACT METHODS IN SUSTAINING A PROPER HYGIENIC LEVEL IN FOOD PROCESSING PLANTS
Autor
Dorota Cais-Sokolińska, Jan Pikul
Pages
53–60
Keywords
bioluminescence, ATP, hygiene
Abstract
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The efficiency of bioluminescence applied to monitor the state of hygiene in a dairy processing plant was assessed in relation to the results of conventional microbiological methods. The used blotting tests were Envirocheck Contact DC with Agar CASO medium with added neutralizers. The analysed object was the surface of a beam stirrer in a fermentation tank. Swabs were collected following tank washing and disinfection after the completion of 15 production cycles. A high degree of correlation r = 0.91 was obtained at the reliability of comparison β= 0.906. The analysis of probability of distribution confirmed the feasibility of bioluminescence. Boundary values (112 and 171 RLU) were determined for bioluminescence for three object cleanliness ranges, based on microbial counts (cfu/cm2). Over 13% surfaces were classified as conditionally clean (Alert).
Mercury poisoning is responsible for inducing serious adverse effects in living organisms. One of protection factors could be substances proven to possess high antioxidant and metal chelating activity – plant polyphenols. There are many sources of polyphenols in plant kingdom but the most interesting for food industry could be widely consumed herbs. Aim of the research was to evaluate antioxidative potential of selected plant extracts and its influence on HepG2 cells in different conditions. Ethanolic herbs extracts were characterised by total polyphenol content. Antioxidant activity was estimated with use of DPPH• and ABTS+• radicals scavenging methods and FRAP. Research included cells viability estimation by the MTT assay and cells exposition to HgCl2, chemical agent inducing cell death. Analysis of herbs extracts antioxidative activity showed best potential represented thyme and marjoram, highest FRAP was evaluated in samples with mint and marjoram extracts. On the basis of received results it was found that examined plant extracts showed weak protection against Hg presence in examined cells environment.