ABSTRACT
Vacuum frying conditions were investigated with respect to physical, chemical and sensorial properties of French fries and frying oil, besides determining the effect of frying conditions in terms of frying temperature and time. In order to determine the optimum frying conditions of the French fries optimization study was carried out according to Central Composite Rotatable Design. The results were evaluated to determine optimum vacuum frying conditions targeting minimum oil content, 30-45 N in range of hardness, minimum acrylamide content and maximum overall preference. The optimum vacuum frying condition was selected as 124.39 °C of frying temperature and 8.36 min of frying time for French fries. The French fries obtained at optimum conditions for vacuum frying preserved the desired color, textural properties and flavor and it has low oil content and reduced acrylamide formation. In addition, the frying oil quality was preserved with vacuum frying.
ABSTRACT
Herein we report a comparison study of the quality characteristics of tomato paste produced under atmospheric conditions and vacuum evaporation. Tomato pulp (5 Brix) was evaporated under vacuum and at atmospheric pressure using a developed evaporation equipment for household application. Various quality i.e. a* and a*/b* color values, soluble solids content, dark speck amount, titratable acidity, lycopene content and sensory properties of tomato paste were compared. The final total soluble solid contents were not affected by evaporation method whereas the lycopene content in vacuum evaporated samples was found as higher than that in the atmospheric ones at the same soluble solid content. Overall preference scores of vacuum evaporated tomato paste have approximately equal scores with the paste produced at atmospheric conditions.
Subject(s)
Solanum lycopersicum , Color , Lycopene , VacuumABSTRACT
Purpose of this study was to develop prototype cooking equipment that can work at reduced pressure and to evaluate its performance for production of strawberry jam. The effect of vacuum cooking conditions on color soluble solid content, reducing sugars total sugars HMF and sensory properties were investigated. Also, the optimum vacuum cooking conditions for strawberry jam were optimized for Composite Rotatable Design. The optimum cooking temperature and time were determined targeting maximum soluble solid content and sensory attributes (consistency) and minimum Hue value and HMF content. The optimum vacuum cooking conditions determined were 74.4 °C temperature and 19.8 time. The soluble solid content strawberry jam made by vacuum process were similar to those prepared by traditional method. HMF contents of jams produced with vacuum cooking method were well within limit of standards.
ABSTRACT
Sour cherries were dried by convectional (CD) at 50, 60, and 70°C and by hybrid (HD; microwave-convectional) drying at 120, 150, and 180W coupled with hot air at 50, 60, and 70°C. In HD, microwave power and hot air were performed simultaneously during drying process. Total phenolic content (TPC), antioxidant capacity (AOC), vitamin C content, color and rehydration capacity were followed. The HD technique reduced drying time and increased drying rate compared to CD. Drying data were well correlated with Verma and modified Logistic models which gave the best fitting for CD and HD, respectively. The modified Logistic model has never been used in food drying areas up to now. The higher TPC, AOC, vitamin C content and rehydration ability were obtained from HD. Color parameters had similar values for both drying methods. The HD technique can be accepted as an alternative drying technique for sour cherry.
