Orange terpenes, oxidation

Orange terpenes were emulsified in various carrier s and spray-dried. The spray-dried powders were aged for 3 days at 80 C in a draft oven. Beta-pinene is an oxidation product in orange terpenes which can be measured by GC. The beta-pinene level is proportional to the degree of oxidation of the orange terpenes. High levels of beta-pinene content in the spray-dried powders indicate poor oxidation resistance imparted to the encapsulated terpenes by the carrier. 

A Beckman Model 4 GC was equipped with a carbowax column, temperature 180 C (inlet). A microliter injection was made and the oxidized beta-pinene peak was measured. The retention time for the oxidized beta-pinene peak is 5.5 minutes. The encapsulated orange terpenes were first dissolved in water before injection. 

Another important aspect of encapsulation efficiency is the resistance to oxidation that the carrier imparts to the flavor oils. The oxidation resistance properties are critical to shelf-life stability of the encapsulated product. Oxidation properties can be measured organoleptically by a taste panel or by gas chromatograph of the recovered oil. Peaks related to oxidation products of orange terpenes obtained from GC analysis can be monitored as the powders are aged for three days at 80 C. The GC was used to measure beta-pinene, an oxidation product of orange terpenes. The results are reported in square inches. The greater the area for the beta-pinene peak, the poorer the oxidation resistance of carrier towards the orange terpenes. The data is presented in TABLE 5 ... 

OXIDATION RESISTANCE OF ORANGE TERPENES vs. CARRIER TYPE... 

Sodium cocoamphoacetate 68647-72-3 d-Limonene Orange Terpenes 68647-73-4 EmCon Tea Tree Tea tree (Melaleuca altemifolia) oil Tea Tree Oil 68647-77-8 Aromox APA-T Chemoxide TAO Tallowamidopropylamine oxide... 

Essentia.1 Oils. Essential oils (qv) are extracted from the flower, leaf, bark, fmit peel, or root of a plant to produce flavors such as mint, lemon, orange, clove, cinnamon, and ginger. These volatile oils are removed from plants either via steam distillation, or using the cold press method, which avoids heat degradation. Additional processing is sometimes employed to remove the unwanted elements from the oils, such as the terpenes in citms oils which are vulnerable to oxidation (49,50). 

The most important (and also the most expensive) grapefruit aroma compound is the bicyclic terpene nootkatone. It is manufactured by oxidation of valencene, which is extracted from Valencia oranges. Figure 1.23 shows two routes for this oxidation, a stoichiometric reaction using chromium trioxide, and a catalytic alternative using sodium hypochlorite (bleach) in the presence of 1 mol% osmium tetraoxide catalyst. 

Tagetes oH. Dark yellow to orange-colored, extremely oxidation-sensitive oil with a typical, terpene-aro-matic, bitter-fruity odor and taste. 

Two samples of papaya oil extracted from dried papaya seed harvested in Somalia yielded 25-26% of an orange-yellow colored liquid with a smell of cress. The composition of fatty acid was similar to other reported values. The relatively high polyphenol content (2.5% in seed oil) gives the seed oil excellent stability to oxidation. The phosphatides are low while the carotenoids are significant (lOmg/lOOg). Unlike the majority of vegetable oils, the terpenic alcohols constituted the most abundant fraction found in the unsaponifiable fraction (Strocchi et al., 1977). 

The main products of limonene oxidation, carvone and carveol, cause a terpenic off-flavour in essential oils and juices. Valencene oxidation products, such as (-F)-nootkatone, cause a grapefruit-like off-flavour in orange juices. Large amounts of alcohol (-F)-o(-terpineol, which arises, for example, during storing of juices by acid catalysed hydration or microbial transformation of limonene, is also perceived as an off-flavour. 

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