Juice manufacture, analysis

The introduction of synthetic materials into natural products, often described as adulteration , is a common occurrence in food processing. The types of compounds introduced, however, are often chiral in nature, e.g. the addition of terpenes into fruit juices. The degree to which a synthetic terpene has been added to a natural product may be subsequently determined if chiral quantitation of the target species is enabled, since synthetic terpenes are manufactured as racemates. Two-dimensional GC has a long history as the methodology of choice for this particular aspect of organic analysis (38). 

To detect adulteration of wine. Bums et al. (2002) found that the ratios of acetylated to p-coumaroylated conjugates of nine characteristic anthocyanins served as useful parameters to determine grape cultivars for a type of wine. Our laboratory utilized mid-infrared spectroscopy combined with multivariate analysis to provide spectral signature profiles that allowed the chemically based classification of antho-cyanin-containing fruits juices and produced distinctive and reproducible chemical fingerprints, making it possible to discriminate different juices. " This new application of ATR-FTIR to detect adulteration in anthocyanin-containing juices and foods may be an effective and efficient method for manufacturers to assure product quality and authenticity. 

Following previous works on physico-chemical characterisation of sunflower low-methoxyl pectins (Alarc o-Silva, 1990, Leitao at al., 1995) and technological utilisation in the manufacture of low calorie gels (Alarc o-Silva et al., 1992), this investigation was carried out to test the suitability of that pectin to the confection of grape juice reduced calorie jellies in comparison with two types of commercial pectin. Aiming at the optimisation of low-calorie jelly formula, based on consumers preferences, the jellies were submitted to a sensory panel test judgement and instrumental texture-analysis. 

As previously indicated, the evaluation of fruit juice will, as a rule, require an expert appraisal of the entire analysis. In practice there will be key parameters to be noted and adhered to during the manufacture of fruit juices and related products. Of these, the soluble solids content and titratable acidity are the major indicators to be taken into account when identifying the status and suitability of a juice product for use in an application. 

If it is a challenge to confirm the authenticity of a herbal extract, it is even more of an analytical challenge in a complex finished product that might contain juice and other ingredients. This means that a manufacturer should check incoming raw materials and that they should be delivered with a certificate of analysis from a reputable laboratory that specialises in this area. 

Oxalic acid, a poisonous compound, is found in certain vegetables such as spinach and rhubarb, but in concentrations well below toxic limits. The manufacturers of a spinach juice concentration routinely test their product using an oxalic acid analysis to avoid any problems from an unexpectedly high concentration of this chemical. A titration with potassium permanganate is used for the oxalic acid assay, according to the following net equation. 

Uses preserving foods, fats, fruit juices, alkaloidal solutions, etc. manufacture of benzoates, benzoyl compounds, and dyes mordant in calico printing curing tobacco as a standard in volumetric and calorimetric analysis pharmaceutic aid (antifungal agent) in plasticizers, perfiimes, cosmetics and dentifrices Cross balsam Peru. ICU, NICU A... 

Ascorbic Acid Concentration. An enzymatic kit from Boeringer Mannheim (Sweden) was used for determination of ascorbic acid concentration in the juice. Before measurement, the packages were shaken and 1 mL orange juice was collected in an eppendorf tube. The juice was then centrifuged at 4000 rpm for 20 minutes and the supernatant was used for analysis as described by the manufacturer (Boeringer cat. No 409677). 

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