Qualidade nutricional, físico-química e sensorial do queijo Minas frescal obtido de vacas em pastejo suplementadas com diferentes níveis de coco babaçu (Orbignya speciosa)

Abstract

The objective of this study was to evaluate the nutritional, physical-chemical, sensory quality and production yield of Minas Frescal cheese from cow milk on pasture receiving different levels of babassu coconut (Orbignya speciosa) in the concentrate. Five multiparous Holstein × Zebu cows were used, with average weight of 456 ± 46.2 kg and with 125 ± 16.5 days in milk at the beginning of the experiment, the animals were arranged in a 5 × 5 Latin square with 21 days. The treatments corresponded to five levels of substitution (0, 20, 40, 60 and 80% of DM) of corn with ground babassu coconut in the concentrated supplement. The supplement was fed ad libitum, twice a day after milking. The animals were kept under rotational grazing in an area formed with Megathyrsus maximus cv. Mombasa. Milk samples were collected on the 19th day of each experimental period and analyzed for fat, protein, lactose, total solids, defatted dry extract, casein, pH and acidity. The milk produced by each animal on the 20th day of each experimental period was used to make cheese, in which the levels of fat, protein, fixed mineral residue, total dry extract, moisture, fat in the dry extract, acidity, pH, yield, colorimetric analysis, fatty acid (FA) profile and sensory acceptance test. The substitution of corn for babassu coconut in the concentrate had no effect on the physical-chemical composition of the cheese (P> 0.05) and on the gross and adjusted yields per kg of processed milk (P> 0.05). However, the gross and adjusted yields in kg of cheese / cow / day decreased linearly (P <0.05). The Proportions (g / 100g of total FA) of short chain FA (4: 0 to 10: 0) in the cheese were reduced linearly (P <0.05) with the increase in the level of babassu coconut in the supplement. The levels of 14: 0 iso increased linearly (P <0.05) in the milk fat of animals that received higher levels of babassu coconut, which was also observed in the levels of 18: 1 trans-11, 18: 2 cis- 9, trans-11 and for the sum of total trans FA and trans monounsaturated FA. The luminosity (L *) and the coordinate (a *), which refers to the green color when negative, had no effect (P> 0.05) with the replacement of corn, while the coordinate (b *), which represents positive for the yellow color, and the saturation index (chroma), were linearly reduced (P <0.05) with the inclusion of increasing levels of babassu coconut. The aroma and appearance of the cheeses showed a quadratic behavior in response to the different levels of babassu coconut inclusion in the diet (P <0.05). Therefore, the replacement up to 80% of corn by crushed babassu coconut in the supplement of grazing dairy cows does not alter the physical-chemical qualities of Minas frescal cheese. However, increasing the inclusion of coconut in the concentrate decreases the yield of cheese production (kg / cow / day) the concentrations of 18: 1 trans-11 and CLA cis-9, trans-11 in the cheese fat and decreases the 18: 2n-6/18: 3n-3 ratio, effects considered desirable from the nutritional point of view due to the beneficial properties to human health attributed to these bioactive FA.