8-Resin Resinous flavours

Crude turpentine is distilled to obtain refined products used in the fragrance and flavour industry. Only the unsaturated mono- and bicyclic terpenes are of interest for resin production. These are mainly a-pinene, p-pinene and dipentcne (D,L-limonene) (Fig. 17). D-Limonene is obtained by extraction of orange peel in citrus fruits. 

Contaminants in recycled plastic packaging waste (HDPE, PP) were identified by MAE followed by GC-MS analysis [290]. Fragrance and flavour constituents from first usage were detected. Recycled material also contained aliphatic hydrocarbons, branched alkanes and alkenes, which are also found in virgin resins at similar concentration levels. Moreover, aromatic hydrocarbons, probably derived from additives, were found. Postconsumer PET was also analysed by Soxhlet extraction and GC-MS most of the extracted compounds (30) were thermally degraded products of additives and polymers, whereas only a few derived from the original contents... 

They are used in many food products and pharmaceuticals to add flavours. Some of these families are manufactured for use as solvents (i.e., acetone) and for preparing materials like adhesives, paints, resins, perfumes, plastics, fabrics, etc. 

While the first two examples of using adsorption methods to produce aroma isolates were from gas streams. Tan et al. [28] applied adsorption methods to the isolation of flavouring extracts from mushroom blanching water. Unfortunately, only an abstract was available of this work so it lacks detail. It appears that they evaluated the use of two different resins (not described) and ethanol, pentane, hexane, and other solvents for desorption. They claim to have had good success in obtaining a useful aroma isolate. 

Methylbutanoates and methylbutyl esters are essential flavour compounds in fruit flavours they can be produced biotechnologically as mentioned before. Chowdary et al. [33] have described the production of a fruit-like flavour isoamyl isovalerate by direct esterification of isoamyl alcohol and isovaleric acid in hexane with the help of Mucor miehei lipase immobilised on a weak anion-exchange resin. 

Large-scale synthesis of (Z)-3-hexenyl acetate in hexane with lipase, (Z)-3-hexenol and acetic acid was described by several authors [40-42]. (Z)-3-Hex-enyl acetate has a fruity odour and shows a significant green note flavour. It can be produced using lipase from Candida antarctica immobilised on an acrylic resin [40, 41] or using immobilised lipase from Mucor miehei [42]. The conversion was reported to be about 90%. 

Furfiirylthiol is a key flavour especially for coffee, beef and roast-like food aromas. It was synthesised in concentrations of up to 1 g L using /1-lyase activity of whole bacterial cells, e.g. Enterobacter cloacae or Eubacterium limosum [256] (Scheme 23.21). Resting cells were used to cleave the sulfur-carbon bond of a furfural-cysteine conjugate and an XAD-4 resin connected to the gas outlet... 

To obtain the characteristic flavourful and aromatic vanilla bean, a long process of controlled fermentation and drying is necessary. The characteristic aroma of vanilla is of vanillin, which is present at a concentration of 1 to 2.5%. Further, vanilla beans contain volatile oils, resins, vanillic acid, /wm-hydroxybenzoic acid, tannins, fixed oils, sugar, gum, waxes and water. 

Moyler, D.A. and Clery, R.A. (1997) The aromatic resins their chemistry and uses, in Special Publication 214 Flavours and Fragrances, Royal Society of Chemistry, Cambridge, UK, pp. 96-115. 

In recycled PP, 61 compounds were detected and 35 of them were identified. Many peaks showed very low separation levels making their identification difficult. In virgin and recycled PP the following compounds were identified Ethylbenzene and xylene were found only in the recycled resin. Present in both virgin and recycled PP were a large number of branched alkanes and n-alkanes between Qg and C25. Octadecanoic acid, methyl ester and dibutyl palmitate, which is a typical compound used in the cosmetic industry, were found only in the recycled PP. Amines such as hexamine, 3-ethyl and NIN"N" trimethyl dipropylene triamine were identified in both PP materials. Carboxylic acids and ketones were absent in both polymeric materials and so were fragrance or flavour compounds [113]. 

Lactic acid 1,2-Propanediol 2,3-Pentanedione, acrylic acid, acrylate polymers, cyclic lactide (dilactide), propylene glycol Acidulant biopolymers, flavourings, pH buffers, preservatives, resins, solvent Polymers Hofvendahl et al., 1999 Hofvendahl and Hahn-Hagerdal, 2000 Datta and Henry, 2006 Bennett and San, 2001... 

The quality of vanilla extract is defined by Winton s analytical values (Merory, 1960) (Table 15.7). The concentration of vanillin is a major criterion, although organoleptic quality does not depend on it entirely. The various characteristic flavour notes that define vanilla are woody, pruney, resinous, leathery, floral and fruity aromatics (Gillette and Hoffman, 1992). Bourbon vanilla serves as the standard by which the chemical and sensory qualities... 

Alpha Packaging manufactures NatureWorks PLA bottles on stretch blow-moulding machines. Alpha states that PLA is ideal for oil-based products, as well as products with flavour and aroma attributes. The PLA resin is FDA-approved and suitable for food contact. It is used for dairy, juice and water bottles, as well as trays for deli meats, salads and single-serve meals. 

Flavouring agents and enhancers are used to create or improve the flavour of a particular foodstuff. This is the biggest group of additives. Some flavours are natural, for example plant extracts and resins, while others are... 

A range of chemicals can also be produced from specialities such as levoglucosan to commodities such as resins and fertilisers as summarised in Table 7. Food flavourings are commercially produced from wood pyrolysis products in many countries. All chemicals are attractive possibilities due to their much higher added value compared to fuels and energy products, and lead to the possibility of a bio-refmery concept in which the optimum combinations of fuels and chemicals are produced. 

As has been shown by Quest International [31], lipoxygenases also accept a relatively broad spectrum of phenolic compounds as substrates. Of interest to the flavour industry are the lipoxygenase-catalyzed conversions of isoeugenol and coniferyl benzoate from Siam resin to vanillin (4-15% peld. Fig. 7.12). At present, the commercialization of these biotransformations is hampered by the... 

Solid-liquid extraction is applied on an industrial scale to produce oils and fats from oil-bearing seeds. In the food and flavour industry, extracts and resins, such as hop, chamomile, peppermint, valerian, vanilla, red pepper and liquorice, are obtained from herbs, roots, seeds and drugs. The technology has also found application in the pharmaceutical industry for the extraction of antibiotics, alkaloids and caffeine. 

Main components During fermentation, vanillin (up to app. 2.5%) is formed from the odourless glucovanillin by enzymatic hydrolysis. Its aroma is rounded-off and modified by p-hydroxybenzoic acid, p-hydroxybenzaldehyde, p-hydroxybenzyl methyl ether, vanillyl alcohol, vanillic acid, cinnamic acid ester and various other trace constituents [291, 292], Also the resins, gums, amino acids and other organic acids contribute to the typical flavour of the cured beans [293[. For further constituents and characterisations of fruits from different growing areas see [294[. 

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