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Active packaging is an innovative and effective way to extend the shelf life of food, but few studies have focused on the effect of its active ingredients on food flavor. This study aimed to develop slow-release polylactic acid/polyhydroxyalkanoates (PLA/PHA) active packaging containing oregano essential oil (OEO) and investigate the effect of active composite packaging on the flavor and quality of pufferfish fillets. The plasticizing effect of OEO increased the elongation at break (EAB) of the films from 23.36% to 65.80%. The adsorption of montmorillonite (MMT) reduces the loss of OEO during processing. The amount of active substance (carvacrol) released from PLA/PHA/OEO/MMT film to pufferfish was 9.70 mg/kg. The pufferfish fillets packed in PLA/PHA/OEO/MMT film showed the slightest difference on the 8th day from the beginning of storage. The slow-release composite films could extend the shelf life of pufferfish fillets by 2-3 days at 4 °C ± 1 °C.

The types and amounts of volatiles in denucleated fruit of 30 Chinese dwarf cherry germplasms were determined by headspace solid-phase microextraction and gas chromatography-mass spectrometry to assess the genotypic variation. Eighty-five volatiles were identified; hexyl acetate, 4-penten-1-yl acetate, prenyl acetate, (Z)-pent-2-enyl hexanoate, geranyl acetate, n-butyl acetate, (3Z)-3,7-dimethylocta-1,3,6-triene, geraniol, pent-2-enyl butanoate, ethyl caprylate, butyl hexanoate, and linalool were the main volatiles. The type and content of volatile varied with genotype. Red fruits had the most abundant aroma and vinicolor fruits exhibited the least. Principal component analysis clustered the 30 Chinese dwarf cherry germplasms into four groups: (1) 2 germplasms (NM2 and HN3) had high ester content, (2) 24 germplasms (BJ1-BJ6, HB1, HB2, HN1, HN2, NM1, NM3, SX1, SX2, SX4-SX6, SX8-SX10, SX12, SX13, SX15, and SX16) contained mainly esters, lactones, and terpenes, (3) 2 germplasms (SX11 and SX14) had high ester and lactone content, and (4) 2 germplasms (SX3 and SX7) had high ester and terpene content.

The volatiles of 75 plums belonging to five species and one interspecific hybrid were investigated by headspace-SPME–GC–MS; 88 volatiles were identified. Prunus salicina and its hybrids had much more compounds and higher contents of volatiles than Prunus domestica and other three Chinese wild species. Aldehydes were the dominant volatiles in P. domestica and Prunus spinosa while esters were the major volatiles in P. salicina, P. salicina hybrids and Prunus ussuriensis fruits. Regarding terpenoids and alcohols, they were relatively high in several P. salicina cultivars, P. salicina hybrids and P. spinosa, and in Prunus cerasifera, respectively. All the plum germplasms could be divided into three groups via principal component analysis: (1) nine cultivars of P. salicina with high ester content, (2) nine Chinese cultivars and one P. salicina hybrid with ester content and two terpenoids, and (3) the rest of the cultivars and three Chinese wild species without characteristic volatiles.

Volatile compounds of three different flavour table-grapes, ‘Jingxiu’, ‘Bimeijia’ and ‘Jingya’, were investigated during and after maturation using SPME/GC–MS. All the alcohols and carbonyls, along with most of the C6 compounds and terpenoids, were evident before veraison, while most of the esters were detected at or after veraison. C6 compounds increased in the early period of maturation, and then decreased. Most alcohols and carbonyls tended to continuously decrease during ripening. Except for geraniol, terpenoids increased until maturation, then decreased. Some esters continued to increase after maturation. Principal component analysis showed that terpenoids and esters were the characteristic volatiles of ripe ‘Bimeijia’ and ‘Jingya’ grapes, respectively. ‘Bimeijia’ had the highest terpenoid content at maturity, while ‘Jingya’ continued to accumulate some esters after maturation. To achieve berries of full-bodied aroma, ‘Bimeijia’ should be harvested at maturity and ‘Jingya’ should have a delayed harvest. For the neutral grape ‘Jingxiu’, delayed harvest is recommended to reduce the ‘green’ odour.

Grape calli systems were used to study the relationships between stilbene production and: (1) four grape genotypes, (2) leaf, berry exocarp and seed tissues and (3) UV-C irradiation. All explants could be de-differentiated. However, subsequent callus growth depended mainly on genotype and tissue type. Non-embryogenic callus accumulated more resveratrols and piceids and had a higher growth index than pro-embryogenic and embryogenic calli. UV-C irradiation for 20 min was most efficient in promoting both the accumulation of resveratrols and piceids and callus growth index. There was dynamic production of resveratrols and piceids in UV-C-irradiated leaf-derived calli over a 72 h period, with optimum harvest time for the highest total stilbene content at 48 h. Accumulation of stilbenes in UV-C-irradiated calli depended upon genetic background and tissue type, with higher stilbene contents in two interspecific root stocks and leaf or exocarp explants.

Using HS–SPME–GC–MS, characteristics of the volatiles of 50 peaches and nectarines representing different germplasm origins were investigated. Ten of these peaches and nectarines were studied in two successive years. Eighty-four compounds were identified. Volatile composition was relatively consistent, but the amount of total volatiles and certain individual compounds varied between years. Moreover, the composition of volatiles and their contents depended on genotypic background and germplasm origin. Total volatiles in wild peaches and a Chinese local cultivar ‘Wutao’ were much higher than in the other groups. All the peaches and nectarines could be classified into four groups by principal component analysis of the volatiles (excluding C6 compounds): ‘Ruipan 14’ and ‘Babygold 7’ with high contents of lactones, Chinese wild peaches and ‘Wutao’ with high contents of terpenoids and esters, seven cultivars with American or European origins with high content of linalool, and others without characteristic composition of volatiles.

Volatile aroma compounds are one of the important characteristics determining fruit quality. Evaluation of volatiles at the germplasm level is useful for future breeding efforts, aimed at improvement of fruit quality, via effects on fruit aroma. The composition and concentration of volatiles in berries of forty-two grape cultivars belonging to seven genotypic groups were evaluated by headspace solid-phase microextraction with GC–MS. Sixty volatiles were detected, of which C6 compounds were the dominant volatiles in V. amurensis grape, neutral cultivars V. vinifera grapes and hybrid grapes between V. vinifera with V. thunbergii or V. amurensis. Alcohols and carbonyls were relatively low in all Vitis germplasm studied. Terpenoids were abundant in V. vinifera with muscat aroma, while esters were dominant in V. labrusca and its hybrids with V. vinifera or V. amurensis. Via principal component analysis, all the grape germplasm studied could be divided into three groups: (1) V. labrusca and its hybrids with V. vinifera or V. amurensis, (2) V. vinifera with muscat aroma and (3) the others, including V. vinifera without muscat aroma plus V. amurensis, and hybrids between V. vinifera and V. thunbergii or V. amurensis. Seasonal quantitative variations of volatiles were observed, but the qualitative volatile composition of the cultivars was consistent.

The composition and content of anthocyanins were surveyed by HPLC–MS for assessing genotypic variation in berry skin of 110 grape cultivars, including 3 species and 5 interspecific hybrids. Twenty-nine anthocyanins were identified. For total anthocyanin content, Vitis vinifera and hybrids of Vitis labrusca and V. vinifera were low, and in general, wild species and rootstock were higher than interspecific hybrids, and wine grapes were higher than table grapes in the same species. As regards the composition of anthocyanins, malvidin-derivatives were the most abundant anthocyanins in the majority of germplasms. All anthocyanins were monoglucoside derivatives in V. vinifera , but all the other Vitis germplasms had both mono- and di-glucoside derivatives. Moreover, peonidin-derivatives and malvidin 3- O -glucoside were, respectively, main anthocyanins in table and wine grapes of V. vinifera . Via principal component analysis, the distribution of the cultivars in a scatter plot depended upon their total anthocyanins content, mono- and di-glucoside derivatives .

0308-8146/$ see front matter 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.foodchem.2010.07.038 DOI of original article: 10.1016/j.foodchem.2010.03.055 * Corresponding author at: Institute of Botany, Chinese Academy of Sciences, Beijing E-mail address: shhli@wbgcas.cn (S. Li). International Partnership Program for Creative Research Teams (Grant No. 0921101001) and the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No. KSCX2-YW-G075-24).