Differences in Bioactive Protein and Vitamin Status of Milk Obtained from Polish Local Breeds of Cows

The Influence of Selected Factors on the Nutritional Value of the Milk of Cold-Blooded Mares: The Example of the Sokólski Breed

This study assessed the effect of access to pasture, lactation number, and foals’ sex on the nutritional value of milk (79 samples) from nine mares. The following were analysed: content of dry matter, protein, fat, lactose, and ash; percentages of α-lactalbumin (α-La), β-lactoglobulin (β-Lg), serum albumin (SA), immunoglobulins (Ig), lactoferrin (Lf), and lysozyme (Lz) in the total protein; and the fatty acid profile. Mares without access to pastures were shown to produce milk with a higher dry matter content, including fat, lactose, and ash; higher percentages of β-Lg, α-La, Ig, and Lf; and a better fatty acid profile. The milk from mares with access to pasture contained more protein, including higher percentages of SA and Lz. Milk from mares in lactations 4–6 had the highest fat and protein concentrations and the lowest lactose concentration. The α-La level was highest in lactation 1, Lf in lactations 2–3, and Lz in lactations 4–6. Milk from mares in lactations 4–6 had the best fatty acid profile (the lowest concentration of saturated fatty acids (SFAs) and the highest concentration of monounsaturated fatty acids(MUFA) and polyunsaturated fatty acids (PUFA)). Milk from mothers of female offspring had higher dry matter, fat, and protein concentrations, a higher share of lysozyme, and a better fatty acid profile.

Organic versus Conventional Raw Cow Milk as Material for Processing

Milk, as one of the basic raw materials of animal origin, must be of adequate hygienic and physicochemical quality for processing. The aim of the article was to compare the quality of raw milk from three production systems, intensive, traditional (together referred to as conventional), and organic, as material for processing, as well as the quality of products made from it. Particular attention was focused on hygienic quality (somatic cell count and total bacterial count), physical characteristics (acidity), basic nutritional value (content of dry matter, total protein, casein, fat, and lactose), content of health-promoting substances (whey proteins, fatty acids, vitamins, and minerals), and technological parameters (rennet clotting time, heat stability, and protein-to-fat ratio). Research assessing the quality of organic milk and dairy products is significantly less extensive (if available at all) than for milk from conventional production (intensive and traditional). The available reports indicate that raw milk from organic farms is more valuable, especially in terms of the content of health-promoting compounds, including vitamins, fatty acids, whey proteins, and minerals. This applies to organic dairy products as well, mainly cheese and yoghurt. This is explained by the fact that organic farming requires that animals are kept in the pasture. However, the hygienic quality of the raw milk, and often the products as well, raises some concerns; for this reason, organic milk producers should be supported in this regard, e.g., through consultancy and training in Good Hygienic Practices. Importantly, milk production in the traditional and organic systems is in line with the concept of the European Green Deal.

Changes in Fatty Acid and Volatile Compound Profiles during Storage of Smoked Cheese Made from the Milk of Native Polish Cow Breeds Raised in the Low Beskids

This study investigated changes in the proximate chemical composition and profiles of fatty acids and volatile compounds of 12 smoked cheeses made from the milk of native Polish cow breeds used in Beskid Niski. Analyses were performed during the shelf life i.e., in the 1st, 21st, 42nd and 69th day of storage. Studies have shown that thanks to smoking and vacuum-packing, the chemical composition of cheese remained stable throughout the whole shelf-life. Up until the 21st day of storage, there were no statistically significant changes in the profile of fatty acids as well as volatile compounds. Changes were observed only after the mentioned storage time. After 21 days, there was a significant (p < 0.05) and steady decrease (up to day 69) in the proportion of odd-chain (by about 36%), branched-chain (by about 17%) and unsaturated fatty acids (by slightly over 1%). Among unsaturated fatty acids (p < 0.05), however, there was a significant increase in the proportion of monounsaturated fatty acids (by 5%) and a decrease in polyunsaturated fatty acids of nearly 12%. Storage lowered (by 47% in the 69th day of storage) the content of the conjugated linoleic acids (CLA), as well as lowered the n6 to n3 fatty acids ratio. During the 69 days of storage, the content of carboxylic acids increased to more than 50%. In the period from the 42nd to 69th day of cheese storage, the content of butyric acid and hexanoic acids increased twofold, whereas that of octanoic acid increased more than tenfold. Fifty-four volatile compounds were identified in the cheese. The largest group was ketones (34%), whose level decreased during storage, with 2-butanone, 3-hydroxy- (acetoin) and 2-butanone predominating. The research found that due to their low odor threshold, carboxylic acids may have negatively affected the flavor profile of the cheese.

The Effect of Selected Factors on the Content of Fat-Soluble Vitamins and Macro-Elements in Raw Milk from Holstein-Friesian and Simmental Cows and Acid Curd Cheese (Tvarog)

Simple Summary

Depending on the region, specific methods of cheese production are used. Acid coagulation is applied in the production of the traditional acid curd cheese highly valued in Poland, called ‘tvarog’. It is important to maintain the traditional nature of production that guarantees cheese with a high nutritional value and health-promoting properties. By conducting an analysis of tvarog, taking into account the quality of the raw milk and the type of starter cultures used, we found that the content of fat-soluble vitamins (A, D₃, and E) mainly depended on the quality of the raw milk from which it was produced. A higher content of fat-soluble vitamins was found in milk obtained from Simmental cows kept in a traditional system in the spring/summer season and in the tvarog produced from it. Vitamin retention rates from raw milk to cheese were above 90%. In contrast, we noticed that the mineral composition of the cheese was not linked to the quality of the milk used. More Ca and Mg were lost with the whey, as indicated by the very low retention rates of these minerals from milk to tvarog (below 20%).

Abstract

The study was conducted to determine the content and retention of selected fat-soluble vitamins and minerals in curd cheese–tvarog made by a traditional method, taking into account the effect of the quality of the raw milk and the type of starter cultures used. The raw milk used to make the tvarog was obtained in various conditions, i.e., with and without the use of pasture forage (in a traditional and an intensive system), in two production seasons (spring/summer and autumn/winter), from two breeds raised in Poland (the Black-and-White variety of Polish Holstein-Friesian and Simmental). Two variants of starter cultures were used to make tvarog: Freeze-dried DVS starters (Flora Danica) and pure cultures of mesophilic lactic acid bacteria. The acidity and content of protein, fat, selected fat-soluble vitamins (A, D₃, and E), and selected macro-elements (Ca and Mg) were determined in samples of bulk milk and cheese. Retention rates of individual nutrients from the milk to the cheese were calculated. A higher content of fat-soluble vitamins was found in milk obtained from Simmental cows kept in a traditional system in the spring/summer season, as well as in the tvarog produced from it. Vitamin retention rates from the raw material to the tvarog were above 90%. The mineral composition of the cheese was not associated with the quality of the milk used. Very low retention rates from milk to cheese were obtained for Ca and Mg (below 20%). Higher retention rates were obtained in the spring/summer season when culture variant 1 was used. However, the starter culture was not found to significantly influence the concentration or retention of vitamins in the experimental cheese.