Heat Induced Browning of Clarified Apple Juice at High Temperatures

Abstract

A procedure to determine deterioration reaction kinetics of fluid foods at elevated temperatures is described. With this method the nonenzymatic browning (NEB) measured as O.D. at 420 nm of Red Delicious (RD) and Granny Smith (GS) apple juices was examined. Color development at 15", 30", 50", and 70" Brix and temperatures ranging from 90-108°C were compared over 60 min. Results indicated an apparent first order reaction rate depending on temperature, apple juice composition and soluble solids. Browning occurred at a more rapid rate in GS juice. NEB reaction rate was shown to depend critically on the total amino acid content. Temperature dependence followed the Arrenhius equation and the activation energy (E,) ranged from 22.G24.8 Kcal/mole.

Physico-chemical and textural quality attributes of pomegranate cultivars (Punica granatum L.) grown in the Sultanate of Oman

“…Arils of Jabal 3 and the wild cultivar were particularly uniform in lightness. Initial aril colour intensity is an important factor affecting colour degradation and kinetics during the production of juice concentrate by heating methods (Maskan, 2006;Vardin and Fenercioglu, 2003;Toribo and Lozano, 1986). Further studies are required to determine the kinetics of colour change of these local pomegranates during heating and other processing operations.…”

Color degradation kinetics of pineapple puree during thermal processing

“…Typically, color is measured by light absorbance at a wavelength specific, being 420 nm, for the fruit under study (Nagy, Lee, Rouseff, & Lin, 1990;Toribio & Lozano, 1986;Wong & Stanton, 1992) as well as by the Hunter parameters (L, a, and b) and total color difference (DE) (Ahmed & Shivhare, 2001;Ahmed, Shivhare, & Debnath, 2002a;Ahmed, Shivhare, & Kaur, 2002b;Buera, Chirife, Resnik, & Wetzler, 1987;Gunawan & Barringer, 2000;Gupte, El-Bisi, & Francis, 1964;Lozano & Ibarz, 1997;Petriella, Resnik, Lazano, & Chirife, 1985;Shin & Bhowmik, 1994;Steet & Tong, 1996;Weemaes, Ooms, Loey, & Hendrickx, 1999). A decline in lightness has been associated with browning in fruit (Labuza, Lillemo, & Taoukis, 1992).…”

Production of pomegranate (Punica granatum L.) juice concentrate by various heating methods: colour degradation and kinetics

“…Before shipping to its final destination the extracted juice is concentrated to ensure longer storage life (because of its low water activity) and easier transportation. The concentration of fruit juices requires partly removal of water without changes in solids composition, leaving all the original solid components such as fruit sugars, minerals and vitamins to the more concentrated solution (Toribo & Lozano, 1986). Concentration of fruit juices, a major unit operation in fruit processing industry, is of critical importance as it determines the quality of the final product such as flavour, colour, aroma, appearance and mouth feel (Jiao, Cassano, & Drioli, 2004;Ramteke, Singh, Rekha, & Eipeson, 1993).…”