Abstract | Poštivanje higijenskih standarda u proizvodnji mlijeka osnovni je preduvjet za pravljenje kiselog vrhnja visoke kvalitete, što je presudno prilikom upotrebe sirovog mlijeka. Cilj ovog rada bio je utvrditi fizikalno-kemijska svojstva, mikrobiološku i senzorsku kvalitetu kiselog vrhnja prikupljenog s većih tržnica na širem području grada Zagreba. Prosječni udio mliječne masti iznosio je 27,99%, proteina 3,30%, suhe tvari 34,29%, suhe tvari bez masti 6,51%, a laktoze 3,00% uz izrazito veliku varijabilnost svih sastojaka vrhnja. S. aureus utvrđen je u 35,30% uzoraka, Enterobacteriaceae u76,47%, E. coli u 94,11% i Bacillus spp. u 23,53% te kvasci u 100% uzoraka dok u vrhnju nije utvrđena prisutnost L. monocytogenes i Salmonella spp.. Senzorskom analizom teksturnih svojstava utvrđena je primjetna varijabilnost u čvrstoći, ljepljivosti, gustoći, punoći i pjenušavosti uzoraka. Uzorci s većim sadržajem mliječne masti i suhe tvari ocijenjeni su bolje za svojstva punoće, gustoće i čvrstoće u ustima, a što je rezultiralo višom ukupnom ocjenom teksture. Ocjene za aromu po vrhnju i diacetilu bile su u širokom rasponu vrijednosti. Ovi rezultati ukazuju na kompleksnost senzorskih karakteristika kiselog vrhnja te na važnost njegovih sastojaka i tehnoloških postupaka u oblikovanju izgleda, mirisa, teksture, okusa i arome. |
Abstract (english) | Compliance with hygiene standards in milk production is a basic prerequisite for the production of high-quality sour cream, which is of crucial importance in the traditional production of cream from raw milk. The aim of this work was to determine the physico-chemical properties, microbiological and sensory quality of sour cream collected from larger markets in the wider Zagreb area. The average percentage of milk fat was 27.99%, protein 3.30%, dry matter 34.29%, dry matter without fat 6.51% and lactose 3.00%, with extremely high variability in all cream components. S. aureus was found in 35.30% of the samples, Enterobacteriaceae in 76.47%, E. coli in 94.11% and Bacillus spp. in 23.53% and yeasts in 100% of the samples, while the presence of L. monocytogenes in the cream and Salmonella spp. was not found. The sensory analysis of the textural properties revealed noticeable variability in terms of firmness, stickiness, density, fullness and foaminess of the samples. Samples with a higher milk fat and dry matter content were rated better for mouthfeel, density and mouth firmness, resulting in a higher overall texture score. The scores for cream and diacetyl flavour were in a wide range. These results indicate the complexity of the sensory properties of sour cream and the importance of its ingredients and technological processes in shaping appearance, odour, texture, taste and flavour. |