Influence of Processing and Pasteurization on Color Values and Total Phenolic Compounds of Pomegranate Juice

Abstract

In this study, the influences of processing and pasteurization on color values and total phenolic compounds of pomegranate juices were investigated. Pomegranate juices were produced by different clarification techniques (conventional fining, conventional fining together with polyvinylpolypyrrolidone [PVPP], ultrafiltration). Nonclarified juice was also produced as control. Clarification methods, heat treatments and methods and heat treatments together significantly (P < 0.05) affected the color values of pomegranate juices. Moreover, conventional fining together with PVPP treatment was found to be the most effective method to remove phenolic compounds.

Fruit Juice Processing and Membrane Technology Application

“…Some authors have studied the use of ultrafiltration as an alternative to sulphiting for the control of enzymatic browning [72,146]. UF is believed to remove polyphenol oxidase and to be effective in stabilizing the colour of fruit juices [5,26,154], but not with lower molecular weight polyphenols or Maillard reaction precursors, which can undergo non-enzymatic browning during the storage of the fruit juice [127]. Galeazzi et al [67] found that banana PPO fractions had molecular weights [30 kDa, within the range of molecular weight cut-offs for UF membranes.…”

The application of high hydrostatic pressure for the stabilization of functional foods: Pomegranate juice

“…In order to highlight the correlation between juice composition and color variation observed after a high pressure treatment as well as intensify the effect of the process on food quality, the color of the fresh and HP treated juices was determined through a detailed spectrophotometric analysis, as reported by Alper et al (2005). The total color density (TCD), color density related to tannins (CDT), the color density related to polymeric substances (PC) of the samples were determined under several operating conditions.…”

“…A double-beam UV-vis spectrophotometer V670 (Jasco-Europe, Italy) was used to measure the chromatic characteristics of the juice samples, according to the procedure reported by Alper et al (2005) for the characterization of pasteurized pomegranate juice.…”

“…The internal seeds are separated by a membranous walls and white, spongy, bitter tissue and filled with sweetly acid red juice. The extraction process is deeply described by Alper et al (2005). The pomegranates were washed with water to remove any surface dirt and superficial microbial flora.…”

The Effects of High Hydrostatic Pressure on the Polyphenols and Anthocyanins in Red Fruit Products

“…The total anthocyanins were determined by a modified pH-differential method, as reported by Alper et al (1996) [4]. The spectrophotometric measurements were carried out using a UV-Vis spectrophotometer (Jasco Europe) and all the absorbance readings were made against distilled water as a blank.…”