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Zawartość immunoglobulin G w mleku w zależności od rasy i wieku krów oraz fazy laktacji

100%

Krol J. , Litwinczuk Z. , Brodziak A. , Karasinska A.

Medycyna Weterynaryjna

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2014

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tom 70

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nr 04

EN

The aim of the study was to analyze the content of immunoglobulin G in milk, with regards to selected physiological (age of cows, stage of lactation), environmental (production season, somatic cell count) and genetic (breed of cows) factors. The study included five breeds of dairy cows: i.e. Polish Holstein-Friesian – Black-White and Red-White varieties, Jersey, Simmental, Polish Red and Whiteback. Milk samples were collected solely from cows with healthy mammary glands; during trial milking which occurred twice a year, once in the winter season, and again in the summer season. In each breed group, according to the breeding documentation, the cows (40 heads in the season) were selected in the appropriate age class (lactation I, II, III and IV) and stage of lactation (up to 120 days, from 121 to 200 days and from 201 to 305 days). A total of 480 milk samples were examined. In each sample the following parameters were determined: somatic cell count (SCC), percentage of protein, including casein, and lactose, concentration of selected whey proteins, i.e. α-LA, β-LG and lactoferrin, and the level of immunoglobulin G (IgG). It has been shown that the cows of local breeds produced a raw material with a higher content of immunoglobulin G. IgG concentration in the milk increased with the subsequent lactations, which might be associated with the significant rise in level of somatic cells with the age of cows, as it was indicated by the significant interaction (p ≤ 0.01) obtained between subsequent lactation and SCC. IgG content also varied significantly during the course of lactation, reaching a peak in the final stage. Moreover, a significant effect of SCC on IgG level in milk was found, which was confirmed by the high value of the correlation coefficient obtained (r = 0.507). A statistically (p ≤ 0.05) significant interaction between breed and SCC for IgG content in milk may indicate a different sensitivity of the analyzed breeds of cows on the somatic cell count increase. This may be due to a variable permeability of the blood-milk barrier in mammary glands.

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Jakość fizykochemiczna i mikrobiologiczna lodów oferowanych na rynku

88%

Krol J. , Karasinska A. , Brodziak A. , Barlowska J. , Kedzierska-Matysek M.

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tom 72

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nr 10

PL

W Polsce od kilku lat utrzymuje się tendencja wzrostowa spożycia lodów, zwłaszcza w sezonie letnim, co związane jest z dużą sezonowością zarówno produkcji, jak i konsumpcji lodów. Napowietrzanie lodów oraz ich podatność na topnienie powoduje, że produkty te są szczególnie wrażliwe na wahania temperatur, a ze względu na swój skład chemiczny stanowią doskonałą pożywkę dla rozwoju niepożądanej mikroflory. Celem pracy była ocena jakości fizykochemicznej i mikrobiologicznej lodów spożywczych i tradycyjnych dostępnych na rynku radomskim. Do badań pobierano próbki lodów oferowanych przez regionalną lodziarnię jako wyrób własny (tradycyjny) oraz od producentów ogólnopolskich (Nestle, Algida i Zielona Budka) - lody przemysłowe. Łącznie pobrano 40 próbek lodów. Próby pobierano w sezonie letnim (lipiec-sierpień) i zimowym (grudzień-styczeń).W każdej próbie lodów oznaczono zawartość tłuszczu, białka, suchej masy, kwasowość (pH i °SH) i puszystość. Prowadzono również oznaczenia, w kierunku wykrywania bakterii chorobotwórczych z rodzaju Salmonella i Listeria monocytogenes oraz liczby Enterobacteriaceae. Lody producentów regionalnych charakteryzowały się ogólnie niską jakością. Aż 75% prób nie spełniało wymagań mikrobiologicznych pod względem liczby Enterobacteriaceae, co świadczy o nieprzestrzeganiu higieny podczas ich produkcji, zwłaszcza w sezonie letnim. Istotnie większym napowietrzeniem charakteryzowały się lody przemysłowe (98,12%), zawierając w swoim składzie więcej suchej masy i tłuszczu w stosunku do lodów tradycyjnych. Ani lody tradycyjne, ani przemysłowe nie przekraczały normy pod względem puszystości.

EN

For several years, there has been an upward trend in the consumption of ice cream in Poland, especially in the summer season. It is related to the high seasonality of both ice cream production and consumption. Aeration of ice cream and their susceptibility to melting cause that these products are particularly sensitive to temperature fluctuations, and because of their chemical composition, they are an excellent medium for the development of undesirable microflora. The aim of the study was to assess the physicochemical and microbiological quality of ice cream, including industrial and traditional ones, available on the Radom market. Ice cream samples offered by a regional ice cream as an own product (traditional), and distributed by the nationwide producers (Nestle, Algida and Zielona Budka) - industrial ice cream were collected for the research. A total of 40 ice cream samples were collected. The samples were collected in the summer season (July-August) and winter season (December-January). The contents of fat, total protein, dry matter, acidity (pH and °SH) and fluffiness were determined in each sample of ice cream. In accordance with the applicable standards, the detection of pathogenic bacteria from the genus Salmonella and Listeria monocytogenes, and determination of the number of Enterobacteriaceae were also carried out. The ice cream from regional producers was generally of low quality. As many as 75% of the samples did not meet the microbiological requirements in terms of the number of Enterobacteriaceae. It indicates a failure to comply with hygiene during their production, especially in the summer season. Significantly greater aeration was characteristic for the industrial ice cream (98.12%), containing more dry matter and fat compared to the traditional products. Both traditional and industrial ice cream did not exceed the standard in terms of fluffiness.

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Zmiany jakościowe wybranych produktów mlecznych w okresie ich przydatności do spożycia

88%

Krol J. , Karasinska A. , Brodziak A. , Stobiecka M. , Barlowska J.

Medycyna Weterynaryjna

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2020

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tom 76

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nr 12