Usporedba fizikalno-kemijskih i senzorskih svojstava sireva u salamuri proizvedenih od mlijeka i mješavine mlijeka i maslinovog ulja

The present paper is focused on the physicochemical and sensory parameters of low-fat white brined cheese-like product obtained from the substitution of milk fat by milk-olive oil emulsion, in comparison with full and low-fat control cheeses. Formulated milk samples were initially pasteurized at 63 °C for 30 min, cooled down to 35 °C, and subsequently 0.35 mL L-1 of microbial rennet were added. The obtained cheeses were stored at 4 °C during 24 hours and then analyzed for physicochemical and sensory properties. The replacement of milk fat in white brined cheese resulted in a lower total solids content due to the higher water-binding capacity of fat replacers used. Fat content was significantly higher for low-fat white brined cheese-like product than in low-fat control cheese. This result was attributed to fat retention capacity of the fat replacers used. Lipolysis index was the highest in the case of low-fat white brined cheese-like product due to changes in cheese microstructure after fat replacers incorporation in low-fat products. Milk-olive oil emulsion showed the lowest cheese-making yield compared to its full and low-fat counterparts. The cheese like- product sample received a significantly lower overall impression score by the panelists than full and low-fat cheeses.Cilj ovog rada bio je usporediti fizikalno kemijska i senzorska svojstva posnih zamjena za sireve u salamuri proizvedenih od mješavine mlijeka i maslinovog ulja u odnosu na posne i punomasne sireve tog tipa. Pripremljeni uzorci mlijeka odnosno smjesa mlijeka i ulja pasterizirani su na 63 °C/30 min, ohlađeni na 35 °C te im je dodano 0,35 mL L-1 sirila mikrobnog porijekla. Proizvedeni uzorci sira čuvani su na 4 °C tijekom 24 sata te je potom provedena analiza fizikalno kemijskih i senzorskih svojstava. Zamjena mliječne masti uljem rezultirala je nižim udjelom suhe tvari uslijed veće sposobnosti vezanja vode od strane zamjenske masti. Udio masti je bio značajno viši u sirnim zamjenama nego u kontrolnom uzroku posnog sira, što se može povezati s kapacitetom zadržavanja masnoća od strane korištene zamjene za mliječnu mast. Najveći indeks lipolize zabilježen je u posnoj zamjeni za sir i to zbog promjena u mikrostrukturi sira koje su nastupile dodatkom zamjena za mliječnu mats i njihove ugradnje zamjenski proizvod. Mješavina maslinovog ulja i mlijeka odlikovala se najnižim prinosom sira, a tako proizvedena zamjena za sir dobila je značajno niže ocjene prilikom senzorskog ispitivanja u odnosu na punomasni i posni sir

Monitoring of dromedary milk clotting process by Urtica dioica extract using fluorescence, near infrared and rheology measurements

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Monitoring of acid-induced coagulation of dromedary and cows' milk by untargeted and targeted techniques

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Monitoring of acid-induced coagulation of dromedary and cow's milk using different complementary analytical techniques

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Characterization of nettle leaves (Urtica dioica) as a novel source of protease for clotting dromedary milk by non-destructive methods

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Proteomic profiling of camel and cow milk proteins under heat treatment

Cow and camel milk proteins before and after heat treatment at 80 C for 60 min were identified using LC/MS and LC–MS/MS following monodimensional electrophoresis. The database used for the identificationof camel and cow proteins was set from http://www.uniprot.org/. The obtained results showed that, afterheating, camel milk at 80 C for 60 min, camel a-lactalbumin (a-la) and peptidoglycan recognitionprotein (PGRP) were not detected while camel serum albumin (CSA) was significantly diminished.When heating cow milk at 80 C for 60 min, a-lactalbumin (a-la) and b-lactoglobulin (b-lg) were not significantlydetected. Moreover, 19 protein bands from SDS-PAGE were analyzed and a total of 45 differentproteins were identified by LC–MS/MS. Casein fractions were kept intact under a heat treatment of 80 Cduring 60 min of both camel and cow milks. Camel and bovine whey proteins were affected by a heattreatment of 80 C for 60 min

Effect of Milk Fat Substitution of Rennet Milk Induced Coagulation on Physico-Chemical Properties

The objective of this paper was to study the effect of milk fat substitution by (W1/O/W2) multiple emulsions based on olive oil in comparison with full and low-fat milks on milk behavior during rennet coagulation. Therefore, based on the turbidimetric and conductivimetric methods, a follow up of enzymatic coagulation is realized. Drainage of renneted gels was followed by syneresis study and cheese yield. The comparison between the coagulation aptitude of low fat milk and milk-olive oil emulsion showed that the hydrolysis phase extended up to 35 minutes for full fat milk and up to 38 minutes for milk-olive oil emulsion. The transition phase solid/gel was shorter in the case of the whole milk. The reticulation phase was shorter in the case of milk-olive oil emulsion. The milk conductivity depended on the milk richness in fat content. Milk-olive oil emulsion showed the lowest cheese-making yield compared to its full and low-fat counterpart

Deposit Generation During Camel and Cow Milk Heating: Microstructure and Chemical Composition

The aim of this study is to identify the chemical composition and the microstructure of the deposits obtainedafter heating camel and cow milks at 80 °C for 60 min using a laboratory-scale device. Like cow milk, camel milk was affected by heat treatment with the reduction of the non-casein nitrogen content reflecting the denaturation of camel whey proteins. The composition of the deposits generated during heating camel and cow milks at 80 °C for 60 min revealed that while camel deposit contained 57 % w/w protein, cow deposit showed a higher protein content of 69 % w/w. The mineral content was 35 % w/w for camel deposit which was higher than that of cow sample, which was 28% w/w. SEMof both deposits showed a familiar structure of a protein deposit with large clumps composed of smaller aggregates. Camel deposit showed an amorphous structure due to its deficiencyin β-lactoglobulin

Impact of spray‐drying conditions on flow properties of skim dromedary and cow's milk powders using the FT4 powder rheometer

International audienceTwo sets of spray-drying conditions were applied on skim dromedary and cow's milks to determine the effect of air outlet temperature (75 and 85°C) and milk type on proximate composition, particle-size distribution, and flow properties of spray-dried powders. The particle-size distribution was more influenced by the chemical composition than the spray-drying conditions. The air outlet temperature impacted on dromedary milk powder flowability, as the basic flowability energy was significantly increased from 620 to 1,018 mJ when the outlet air temperature was increased from 75 to 85°C, respectively. Specific energy, associated with the flow performance of a powder in a low-stress environment, was significantly higher for dromedary milk powder at the higher air outlet temperature. However, spray-drying conditions had no significant effect on specific energy values of cow's milk powder. Dromedary milk powders had better flow behavior than cow's milk powders. Shear tests confirmed that powders spray-dried at 75°C had better flowability than powders spray-dried at 85°C

Enzymatic coagulation of raw and reconstituted skim dromedary and cows’ milk powders: Kinetics, rheological and morphological properties

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