Changes in aromatic volatile composition of strawberry after high pressure treatment Y. Lambert a,b, *, G. Demazeau a , A. Largeteau a , J-M. Bouvier b a Ecole Nationale Supe Ârieure de Chimie et de Physique de Bordeaux, Interface Hautes Pressions, Avenue Pey Berland, BP 108, 33400 Talence, France b CLEXTRAL, Z.I de Chazeau, BP 10, 42 702 Firminy, France Received 7 December 1998; received in revised form and accepted 9 February 1999 Abstract The aromatic volatile compounds of high pressure treated strawberry coulis (Fragaria ananassa Gariguette) were analysed by capillary gas chromatography±mass spectrometry (GC±MS) and compared with aromatic volatile compounds of raw strawberry and heat-treated strawberry coulis. Characterisation of treated and untreated samples was achieved by applying principal compo- nent analysis to the chromatographic data. Aroma of strawberry was speci®cally identi®ed by furaneol (2,5-dimethyl-4-hydroxy- furan-3-one) and nerolidol (3,7,11-trimethyl 1,6,10-dodecatrien-3-ol). No signi®cant changes of all the aromatic volatile compounds were observed between untreated and high pressure-treated (200 and 500 MPa, 20  C, 20 min) strawberry coulis. On the other hand, changes appeared in the composition of aromatic compounds after an ultra high hydrostatic pressure treatment at 800 MPa (20 min, 20  C) and after a sterilisation (120  C, 20 min). # 1999 Elsevier Science Ltd. All rights reserved. 1. Introduction The strawberry is a classic example of a sought-after quality fruit that is, unfortunately, also highly perish- able. Ensuring that top quality strawberries reach the consumer in perfect condition requires very careful attention to their distribution, storage and ®nal display in the shops. Fresh strawberries have a very short life because they are easily bruised and the fact that `if nothing is done' they quickly succumb to fungal attack, principally from Botryris cinerea (Guichard, Chambroy, Reich, Fournier & Souty, 1992). At the moment those cultivars with exceptional ¯avour are sold at a premium for fresh fruit distribution but this quality dierential for fresh fruit becomes less marked after the fruit has been subjected to traditional methods of processing. Because of this, the producers (and potential pro- cessors) of high quality strawberries are interested in any new process that could help to extend the range of processed food products if the quality dierential with respect to other cultivars is maintained. Such a process would retain the organoleptic properties of the raw fruit (that is its texture, colour, taste and smell) as well as the vitamins. The quality, then, would be irreproachable and equivalent to that of the raw fruit though not necessarily presenting the same aspect. Market research has shown that there is a marked demand for high qual- ity fruit components as ingredients in processed food products. These products could be in the form of coulis, sauce, jam or other products that might, for example, form part of a processed milk or dessert preparation. The traditional process for stabilising and conserving foodstus has been the thermal process and its use in modern food processing has relied on increasingly higher temperatures. One of the consequences of this is that not only does the texture and ¯avour of the food- stu suer but the vitamins and smell can be destroyed and the damage can even extend to the production of toxic compounds (Hayashi, 1995). In contrast to this, the use of high pressure for stabilising and conserving foodstus retains the ¯avour (Cheftel, 1995), the colour, the taste of the natural foodstus (Butz, Koller, Tauscher & Wolf, 1994) and the natural properties of the pro- ducts (Balny, Heremans & Masson, 1992). It would appear, therefore, that high-pressure technology could become a powerful tool for taking advantage of the opportunities oered by the `top of the range' quality fruits as represented by certain cultivars of strawberries. Food Chemistry 67 (1999) 7±16 www.elsevier.com/locate/foodchem 0308-8146/99/$ - see front matter # 1999 Elsevier Science Ltd. All rights reserved. PII: S0308-8146(99)00084-9 * Corresponding author. Tel.: +33-556-842-737; fax: +33-556-842- 710. E-mail address: lambert@chimsol.icmcb.u-bordeaux.fr (Y.Lambert)