Processing and Storage Effects on Orange Juice Aroma: A Review

Abstract

Freshly squeezed orange juice aroma is due to a complex mixture of volatile compounds as it lacks a specific character impact compound. Fresh hand-extracted juice is unstable, and thermal processing is required to reduce enzyme and microbial activity. Heating protocols range from the lightly heated not from concentrate, NFC, to the twice heated, reconstituted from concentrate, RFC, juices. Thermal processing profoundly effects aroma composition. Aroma volatiles are further altered by subsequent time-temperature storage conditions. Heating reduces levels of reactive aroma impact compounds such as neral and geranial, and creates off-flavors or their precursors from Maillard, Strecker, and acid catalyzed hydration reactions. Off-flavors such as 4-vinylguaiacol, p-cymene, and carvone are the products of chemical reactions. Other off-flavors such as butane-2,3-dione, guaiacol, and 2,6-dichlorophenol are indicators of microbial contaminations. Since most orange juice consumed worldwide is processed, the goal of this review is to summarize the widely scattered reports on orange juice aroma differences in the three major juice products and subsequent aroma changes due to packaging, storage, and microbial contamination with special emphasis on results from GC-O studies.

Identification of Different Pink Pomelo Varieties by Gas Chromatography-mass Spectrometry and Olfactometry Coupled to Chemometrics

“…As reported, aldehydes play an important role in contributing to citrus flavour [28]. For aldehydes, the content was generally from 0.21% (MJ samples) to 6.42% (NH samples) among these six pink pomelo samples.…”

Local processing and nutritional composition of indigenous fruits: The case of monkey orange (Strychnos spp.) from Southern Africa

“…(3) In orange juice processing, high mechanical extraction pressure application, de-pulping and aeration conditions can reduce the volatile components and alter the flavor of the resultant juice. (69) Since traditional monkey orange juice extraction is mild due to equipment constraints and processing steps are limited to heating and hand extraction, the extent of aroma alteration and odor development by processing is hypothesized to be minimal though there are no studies to this effect. Saka et al (27) identified a reduction in the mineral elements calcium and magnesium from fresh to processed juice of S. cocculoides.…”

Non-enzymatic browning in citrus juice: chemical markers, their detection and ways to improve product quality

“…Extensive amount of literature on markers of NEB and analytical methods to monitor NEB in citrus juice have been reported; but no comprehensive review published on these aspects. Recently Perez-Cacho and Rouseff published a review on the processing and storage effects on orange juice aroma (Perez-Cacho and Rouseff 2008). Herein, we have reviewed the chemistry of NEB, markers of NEB, analytical methods to monitor NEB or detect markers of browning and ways to improve the quality of juice.…”