Effects of pomace maceration on yield, turbidity, cloud stability, composition of phenolics, antioxidant activity and colour properties were studied, to evaluate the potential applicability of enzyme preparations in puree-enriched cloudy apple juice production. The yield of mixed juice and puree from pomace obtained in the enzymatic processing of apple ranged from 92.3% to 95.3%, significantly higher than the yield from the control without enzymatic pomace treatment (81.8%). Higher turbidity was obtained upon pomace treatment with Pectinex XXL and Pectinex Ultra SPL enzymes. The total content of phenolic Blazer Nike Noir compounds in apple pomace was higher than in raw juices (1520 mg/kg and 441 mg/L, respectively). The total polyphenol yields were higher in juices treated with Pectinex AFP L-4, Pectinex Yield Mash and Pectinex XXL, as compared to the control treatment. During 6 months of storage, a significant change was observed in the content of polyphenols, especially in procyanidin fractions.
The a.c. electrical conductivity Blazer Nike Noir of AgTlSO4 has been measured at T between 365 K and 704 K and at P between 6.3 kbar and 49.5 kbar. The decrease in conductivity, σ, with P and the diminishing σ jump at the phase transition observed in our 1 atm DSC and dilatometric studies, are consistent with a simple volume-controlled cationic conduction mechanism. The shift of the transition to higher T with increasing P is in accord with LeChatelier's principle. The dependence of Qc on P for the high temperature phase is effectively linear for both heating and cooling. The ΔV‡ value of 16.4 cm3 mole−1 for the high temperature phase at 667 K between 6.3 kbar and 18.3 kbar is exceptionally high. Dilatometric traces recorded at l atm between 373 K and 523 K show an expansion of 1.47% at the ~465 K phase transition. Using the measured expansion and density of AgTlSO4, we obtain the enthalpy of transition ΔHt Chaussure Nike Blazer = 25.7 kJ mole−1 from the Clapeyron equation in fair agreement with ΔHt determined from calorimetry.
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