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Abstract:The study was aimed to (i) test the effect of polyethylene (LDPE) films coated by commercially available polyvinylchloride (PVC) lacquer with addition of nisin preparation Nisaplin ® (5% w/w) and/or natamycin preparation Delvocid TM (10% w/w) on the growth of target bacteria, yeasts and moulds on the surface of soft cheese Blaťácké zlato produced by company Madeta, a.s., Veselí nad Lužnicí, and (ii) prepare and study the antimicrobial films with incorporated lactic acid or sodium lactate, suitable for packaging of raw chicken meat. The cheese in contact with nisin/natamycin treated film was stored at temperature 4°C and 23°C for 23 days, while chicken meat packaged in lactic acid/sodium lactate releasing films was stored only at 4°C for 7 days. Released antimicrobial agents caused retardation of tested microorganism growth by more than 1 logarithmic cycle on the surface of cheese Blaťácké zlato and by more than 2 logarithmic cycles in raw chicken meat.

Abstract:© Versita Sp. z o.o. Keywords: Antimicrobial packaging • Immobilization • Glucose oxidase • Lysozyme Research ArticlePackaging based on immobilization of antimicrobial enzymes provides a promising form of active packaging systems applicable in food processing. Glucose oxidase and lysozyme were immobilized by the Ugi reaction with cyclohexyl isocyanide and glutaraldehyde on polyamide and ionomer films partially hydrolysed by hydrochloric acid. The immobilization of the enzymes on the surface of films was confirmed by FT-IR spectroscopy and the films were characterized by the specific activity of the immobilized enzymes. The enzyme migration into model solutions and the effect of pH, temperature and storage time on the activity of immobilized enzyme were also

HANUŠ, O., SOJKOVÁ, K., HANUŠOVÁ, K., SAMKOVÁ, E., HRONEK, M., HYŠPLER, R., KOPECKÝ, J., JEDELSKÁ, R.: An experimental comparison of methods for somatic cell count determination in milk of various species of mammals. Acta univ. agric. et silvic. Mendel. Brun., 2011, LIX, No. 1, pp. 67-82 Somatic cell count (SCC) is important foodstuff , hygienic and health indicator of milk and animal mammary gland. The goal of this paper was to evaluate an ability of chosen methods to reach the SCC reliable results in various biological kinds (species) of milk. The various methods of SCC determination were compared in cow (CM), goat (GM), sheep (SM) and human (HM) milk: direct microscopy (DM); fl uoro-opto-electronic (Fossomatic 90; Foss); fl uorescent (DCC; De Laval). Used methods had cow milk calibration basically. The DM, Foss and DCC result relations about SCC were very close, mostly > 0.92 (P < 0.001) for CM, GM and SM. In CM the regression equations between methods were near ideal form y = 1x + 0. The mean diff erences SCC data sets between mentioned methods were small for CM, larger for SM and HM and the largest for GM. It is possible to convert all DCC results in SM, HM and GM to DM or Foss method. The conversion equations were stated from DCC: to DM in cow milk y = 1.1293x − 5.5029; to Foss in goat milk y = 3.603x − 3171.4; to Foss in sheep milk y = 1.3805x − 18.149; to Foss in human milk y = 2.6246x + 158.63. Assesment of conversion equations should be individual laboratory event. Results had relatively good correspondence among DM, Foss and DCC for SCC determination in CM, GM, SM and HM for milk quality control. DCC had lower results in small ruminants as compared to Foss calibrated on CM using DM. DCC in HM had lower results as Foss adjusted by CM at good correlation (0.84; P < 0.001).Address doc. Ing.

HANUŠ, O., HRONEK, M., HYŠPLER, R., YONG, T., TICHÁ, A., FIKROVÁ, P., HANUŠOVÁ, K., SOJ-KOVÁ, K., KOPECKÝ, J., JEDELSKÁ, R.: Relationship between somatic cell count and lactose content in milk of various species of mammals. Acta univ. agric. et silvic. Mendel. Brun., 2010, LVIII, No. 2, pp. 87-100 Somatic cell count (SCC) is an indicator of mammary gland health state. Lactose (L) can be reduced with mastitis and SCC increase. Mammary gland health is an essential factor of milk quality. Monitoring of mammary gland health is important for prevention and treatment of milk secretion disorders. The goal of this work was to analyse the relationship between SCC and L in various biological species. 7 sets of individual and bulk milk samples (MSs) were analysed (n = 479, 479, 345, 80, 90 and 102) for SCC and L content. 3 sets were with cow (C) milk and 1 set with goat (G), 1 with sheep (S) and 1 with human (H) MSs. The relations in C milk were used as reference. SCC geometric means were markedly lower in C milk (62, 99 and 81 10 3 . ml −1 ) and H milk (103 10 3 . ml −1 ) as compared to small ruminants (G 3 509 and S 609 10 3 . ml −1 ). The mean L values were lower in small ruminants (G 4.36% and S 4.42%) as compared to C milk (4.95%, 4.97% and in 1st lactation 5.10%) and higher in H milk (5.77%). L contents in Czech Fleckvieh and Holstein correlated negatively to SCC (log SCC)) in all lactations (−0.36 P < 0.001 and −0.33 P < 0.001). L content in 1st lactation correlated with SCC markedly narrower than in cows for all lactations (−0.49 P < 0.001). The SCC×L relationship in G (White short-haired) milk (−0.35 P < 0.01) was in good relation to C milk and in S (Tsigai) milk (−0.51 P < 0.001) was markedly narrower as in C and G milk. Lower mean SCC in H milk as compared to G and S milk and comparable to C milk did not show signifi cant negative relationship to L which was 0.08 (P > 0.05) for original SCC values. Surprisingly there was not found the SCC×L relationship in H milk which could be comparable to other mammal species milk. It could be caused by bacteriologically negative results in MSs with higher SCC (> 300 10 3 . ml −1 ). As well as at C milk also at G and S milk and in contrast to H milk it is possible to use the SCC×L relationship for improvement of result interpretation and prevention control in occurrence of milk secretion production disorders in routine monitoring systems such as milk recording with individual MSs and milk quality control with bulk MSs. The quality of decision-making schemes in algorithms for practical monitoring of mammary gland health could be improved. cow, sheep, goat, human milk, milk secretion disorders, lactose, somatic cell count, regression, milk recording Disacharid laktóza (L; C 12 H 22 O 11 , glukóza a galaktóza) je specifi ckým produktem laktogenní syntetické činnosti mléčné žlázy. V důsledku její produkce dosahuje koncentrace cukru v kravském mléce až stonásobku koncentrace v krevní plazmě (glukóza) v situaci, kdy krev přináší živiny (mléčné složky a jejich prekurzory...