Fruit Bartlett pear

Pears. Triplicate samples of 20 Bartlett pears each were used and a fourth sample was placed in cold storage for subsequent examination, as with the apples. Washing trials were performed in a standard type washer (an Ideal fruit washer with an unheated main tank unit and a water rinse tank unit, Model WKA, manufactured by the Ideal Grader and Nursery Company, Hood River, Ore.). 

The flavour of distillates from apple and pear is characterised by typical aroma compounds from these fruits formed by enzymatic degradation of fatty acids to C6-fragments like hexanol, trans-2-hexenol, as well as ethyl esters and acetates of hexanoic acid. In distillates of pears, especially of the variety Bartlett pear, the characteristic pear flavour is mainly dominated by the ethyl and methyl esters of frans-2-czs-4-decadienoic acid and trans-2-trans-A-decadienoic acid [27-29], The biogenesis of these monounsaturated, diunsaturated, and triunsaturated esters may be explained by -oxidation of unsaturated linoleic and linolenic acid in the fruits. The sesquiterpene compound a-farnesene, which is formed during postharvest ripening and storage of Bartlett pears [28], shows that quality and intensity of distilled pear spirits is mainly influenced by the quality and degree of ripeness of the fruits. 

Methanol occurs in some foods. Distilled fruit spirits such as those from the fermentation of Bartlett pears contain some methanol. This has led to European standards for methanol limits in distilled fruit spirits. The levels of methanol can be reduced by appropriate adjustment of fermentation conditions and the distillation processes used.3... 

Polyunsaturated aliphatic alkohols, aldehydes, ketones, and esters occur as fragrance components in fats, oils, fruits and plants 158). As an example the synthesis of ethyl (2 ,4Z)-2,4-decadienoate (232, pear ester ), which is responsible for the aroma of bartlett pears 161) is given. 2,4-Diunsaturated ester 232 may be obtained by a number of highly stereoselective syntheses, a lot of them making use of the Wittig reaction. Ohloff and Pawlak condensed 4,5-epoxy-( )-2-pentenal 228 with the ylide generated from 229 (butyllithium/ether) to the alkadiene epoxide 230 which was oxidized with periodic acid to the 2,4-decadienal 231. 231 is subsequently converted with MnOj/NaCN in ethanol to the pear ester 232162) [75 % (Z)-amount of the C-4 double bond] (Scheme 44). 

Aliphatic esters in various combinations play a major part in many flavors, particularly fruit flavors 441), Hexyl acetate develops the strongest and most typical odor in Cox s Orange Pippin apples (279). Hexyl 2-methylbutyrate contributes highly to the flavor of Golden Delicious apples (265). Methyl and ethyl esters of ( )-3-hexenoic, (Z)-4-decenoic (32) and )- and (Z)-4-octenoic acids have some importance in the flavor of pineapple 408). Methyl (Z)-4-decenoate (32) and methyl thiohexanoate account for about 56% of the odor provided by the components of the oxygenated fraction of hop oil 202). Ethyl (jE, Z)-2,4-decadienoate (35) is considered as the character impact compound in the aroma of Bartlett pears (227) (Table 2). The application of this pear ester in reconstitution work has been facilitated by the development of highly stereospecific syntheses 405, 407, 457). Isobutyl an-gelate is considered as an essential constituent of Roman camomile oil 85). 

Before windsurfing became a big hit, Hood River was famous among epicureans for its orchards and vineyards. The area s fruits are coveted by gourmet chefs worldwide. In the autumn, take a drive down the Mt. Hood Loop tour and stop at any of the fruit stands along the way. Another way to enjoy the local bounty is to visit the Hood River Harvest Festival held in mid-October. Pick up locally grown winter pears, Bartletts, Newton apples, cherries and peaches amid a backdrop of colorful fall foliage. Admission to the festival is free. 

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