Effect of Processing Techniques at Industrial Scale on Orange Juice Antioxidant and Beneficial Health Compounds

Abstract

Phenolic compounds, vitamin C (L-ascorbic acid and L-dehydroascorbic acid), and antioxidant capacity were evaluated in orange juices manufactured by different techniques. Five processes at industrial scale (squeezing, mild pasteurization, standard pasteurization, concentration, and freezing) used in commercial orange juice manufacturing were studied. In addition, domestic squeezing (a hand processing technique) was compared with commercial squeezing (an industrial FMC single-strength extraction) to evaluate their influences on health components of orange juice. Whole orange juice was divided into soluble and cloud fractions after centrifugation. Total and individual phenolics were analyzed in both fractions by HPLC. Commercial squeezing extracted 22% more phenolics than hand squeezing. The freezing process caused a dramatic decrease in phenolics, whereas the concentration process caused a mild precipitation of these compounds to the juice cloud. In pulp, pasteurization led to degradation of several phenolic compounds, that is, caffeic acid derivatives, vicenin 2 (apigenin 6,8-di-C-glucoside), and narirutin (5,7,4'-trihydroxyflavanone-7-rutinoside) with losses of 34.5, 30.7, and 28%, respectively. Regarding vitamin C, orange juice produced by commercial squeezing contained 25% more of this compound than domestic squeezing. Mild and standard pasteurization slightly increased the total vitamin C content as the contribution from the orange solids parts, whereas concentration and freezing did not show significant changes. The content of L-ascorbic acid provided 77-96% of the total antioxidant capacity of orange juice. Mild pasteurization, standard pasteurization, concentration, and freezing did not affect the total antioxidant capacity of juice, but they did, however, in pulp, where it was reduced by 47%.

Nutritional Composition of Orange Juice: A Comparative Study between French Commercial and Home-Made Juices

“…Besides, the sample of home-made OJ was built to reflect the usual attitudes and practices of French consumers, as recorded from a consumer survey. These characteristics made our work original as compared with previous studies in this area, which did not consider commercially available OJ or home-made OJ prepared following usual consumer's practices (e.g., [6] [17] [22]). …”

Designer fruits and vegetables with enriched phytochemicals for human health

“…Ferreira et al (2002) found that total phenolic content in pears decreased by 64% under sun-drying conditions. Freezing, pasteurization, boiling and microwave cooking can reduce the total antioxidant levels (Gil-Izquierdo et al 2002;Guyot et al 2003;Aziz et al 1998). One exception is perhaps the processing of tomatoes.…”

Hydrophilic antioxidant compounds in orange juice from different fruit cultivars: Composition and antioxidant activity evaluated by chemical and cellular based (Saccharomyces cerevisiae) assays

“…Besides phenolic compounds, Vitamin C is considered the most important water-soluble antioxidant that contributes to the antioxidant cellular defence against oxidative stress. The profile of the antioxidant compounds in OJ shows quantitative and qualitative differences related to the genotype (variety), environmental conditions (sunlight, rain, temperature), agronomic practices (type of crop and harvesting conditions), fruit maturity and technological processes (thermal, mechanical) and storage (Klimczak et al, 2007), all of which affect compound content and consequently antioxidant capacity (Dhuique-Mayer et al, 2005;Gil-Izquierdo et al, 2002;Mouly et al, 1997).…”