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In this research, whey cheese Urda was produced in industrial conditions by thermal denaturation, followed by protein aggregation and precipitation of whey which was obtained during production of white brined cheese and Kashkaval. The impact of milk pasteurization temperature, pH values, protein content, and whey type on the Urda quality and yield was examined. The impact of whey pH on Urda yield was evaluated in the pH range from 4.5 to 6.0. Urda yield reached a maximum pH value between 5.2 and 5.4. The highest Urda yield from white brined cheese whey was obtained at pasteurization temperature of 72 °C. By increasing the temperature to 80 °C, the whey protein content and the Urda yield decreased. Whey type had no significant impact on the sensory and textural characteristics of Urda. Urda was classified as a low-fat soft albumin cheese. Valorisation of whey generated after production of white brined cheese, and manufacturing of Urda with maximum yield and optimal functional properties, is not only of economic importance, but can be conducive to improve waste water quality., U ovom je istraživanju u industrijskim uvjetima proizveden sir urda primjenom toplinske denaturacije koja je rezultirala koagulacijom i izdvajanjem proteina iz sirutke dobivene u procesu proizvodnje sira u salamuri te kačkavalja. Pritom je ispitivan utjecaj temperature pri kojoj je provedena pasterizacija, pH vrijednosti, sadržaja proteina i vrste sirutke na prinos i kvalitetu urde. pH sirutke kretao se između 4,5 i 6,0, a najveći prinos urde postignut je pri pH vrijednostima između 5,2 i 5,4. Pri korištenju sirutke dobivene proizvodnjom sira u salamuri kao ishodišne sirovine, najviši prinos urde postignut je pri temperaturi pasterizacije od 72 °C. Daljnjim povećanjem temperature do 80 °C smanjivao se prinos urde i udio proteina sirutke. Vrsta korištene sirutke nije značajno utjecala na senzorska svojstva i parametre teksture urde koja je svrstana u kategoriju niskomasnih mekih albuminskih sireva. Iskorištavanje sirutke koja zaostaje u proizvodnji sireva u salamuri te proizvodnja urde optimalnih funkcionalnih svojstava uz maksimalan prinos nije važno samo s ekonomskog stajališta, već može značajno utjecati i na poboljšanje kvalitete otpadnih voda.

The aim of this study was to evaluate the effect of different solutions for vacuum impregnation (VI) of fresh-cut (FC) apples through an innovative multi-analytical approach. In particular, the individual and synergistic effects of ascorbic acid and calcium lactate on the preservation of freshness of FC apples was assessed through color, texture, microscopy, isothermal calorimetry, and time-domain nuclear magnetic resonance (TD-NMR) evaluations. The analysis was performed immediately after VI and after 24 h of refrigerated storage. The obtained results showed a good preservation of color and higher firmness in the impregnated samples. Concerning the metabolic heat production, a decrease following the VI treatment was observed, especially when the combined solution was used for the impregnation. The TD-NMR studies showed higher changes in terms of signal intensity and transversal relaxation time T2 after 24 h of storage, evidencing the meta-stability of the plant material for its dynamic tissue nature, and the dewatering/impregnation processes evolution until the achievement of dynamic equilibrium.

Texture and structure of breads have been related to oral processing (FOP) performance and sensory perceptions, but moisture content might play a significant role. To evaluate the real impact of breads texture and structure, eliminating the possible role of moisture content, different toasted breads were investigated. Four commercial toasted sliced breads (white bread -WHB-, whole wheat bread -WWB-, non-added sugar bread -NSU-, non-added salt bread -NSA-) with similar ingredients but different texture and structure were selected. Texture and structure were instrumentally and sensory evaluated, besides FOP (total chewing time, number of chews until swallowing, chewing frequency, and mouthful) and bolus properties (moisture, saliva to bread ratio, hardness, adhesiveness, and cohesiveness). Toasted breads showed significant differences in hardness, cutting strength, and porosity, but panelists did not discriminate among them. FOP results indicated that harder samples (NSU) required longer mastication and a number of chews, and open crumb structures (WWB, WHB) with higher cell areas required less mastication. Also, bolus characteristics were affected by bread types, and bread with lower crumb hardness (WHB) produced more cohesive bolus. Having toasted breads allowed to eliminate possible influence of moisture content differences on sensory perception, mouthful and bolus water incorporation during mastication.