辣椒红色素的稳定性及在食品中的应用研究

研究了辣椒红色素的稳定性以及在食品中的应用.研究发现,辣椒红色素对热稳定;辣椒红色素在pH=2-12之间色素稳定;在暗室和室内光线下,色素无褪色现象,在日光下不到半天的时间色素几乎损失殆尽,紫外光对色素有明显的影响;Cu2 与色素发生反应,色泽改变,其它金属离子(Sn2 、Al3 )浓度大于300mg.ml-1对色素有一定影响;辣椒红色素对还原剂和防腐剂稳定,对氧化剂不稳定.本文还研究了辣椒红色素在食品中的着色及稳定性.     

Determination of polyphenol levels variation in Capsicum annuum L. cv. Chelsea (yellow bell pepper) infected by anthracnose (Colletotrichum gloeosporioides) using liquid chromatography–tandem mass spectrometry

Healthy fruits of Capsicum annuum L. cv. Chelsea (yellow bell pepper) and one infected by Colletotrichum gloeosporioides were analysed for polyphenols via high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC–MS/MS). Among seven polyphenols characterized, four components in the C. annuum fruits were identified for the first time. To investigate the characteristics of the polyphenols as defence materials, the content change of the fruit polyphenols inoculated with C. gloeosporioides was monitored by HPLC. It was observed for the first time that de novo induced N-caffeoyl putrescine (1) and caffeoyl O-hexoside (2) appeared to act as a phytoalexin in the defence mechanism of the C. annuum fruits against C. gloeosporioides, and constitutively formed feruloyl O-glucoside (3), kaempferol O-pentosyldihexoside (4) and dihydroxyflavone O-hexoside (7) as a phytoanticipin in the diseased C. annuum fruits.     

Changes in volatile compounds of Habanero chile pepper (Capsicum chinense Jack. cv. Habanero) at two ripening stages

The steam volatile components of Yucatan Habanero chile pepper (Capsicum chinense Jack. cv. Habanero) at two ripening stages (green and orange) were analyzed using GC and GC/MS. Both samples had several compounds in common. One hundred and two compounds were identified, from which (E)-2-hexenal, hexyl 3-methylbutanoate, (Z)-3-hexenyl 3-methylbutanoate, hexyl pentanoate, 3,3-dimethylcyclohexanol, and hexadecanoic acid were found to be the major constituents. During Habanero chile pepper maturation, the majority of volatile compounds decreased or even disappeared, some of them with green odour notes while esters, which have fruity odour notes, increased at the same time.     

低温胁迫对青椒膜脂代谢的影响

目的为了研究低温胁迫对青椒膜脂代谢的影响。方法以“晋黎”青椒为实验材料,测定10℃(对照)和4℃(低温胁迫)等不同贮藏温度下青椒相对电导率、丙二醛(MDA)、脯氨酸、磷脂酶D(PLD)、脂氧合酶(LOX)活性、脂肪酸组分的变化情况。结果在低温胁迫下,青椒的相对电导率升高,MDA积累,脯氨酸含量增加,PLD和LOX活性升高,亚油酸、亚麻酸减少,硬脂酸增加,脂肪酸不饱和指数降低。结论低温胁迫诱导青椒PLD和LOX活性上升,引起不饱和脂肪酸降解,饱和脂肪酸增加,膜流动性减弱,最终导致膜失去完整性,在这过程中脯氨酸含量明显升高。     

The effect of a natural antioxidant on the stability of heat-treated paprika

The colour loss occurring in a paprika made from the dehydrated fruits of pepper, Capsicum annuum L. var. Ocal (control), was compared with the colour lost by a similar paprika submitted to an industrial sanitation process involving water vapour. The heat treatment resulted in a considerable greater loss of colour when the paprika was stored at 25 °C in different relative humidities (0, 23, 57 and 75%) compared with the control paprika. The study also analysed the effect of adding a natural antioxidant (rosemary extract at 1%) to the heat‐treated product. In this case, colour stability increased significantly in all the conditions assayed; the lower the humidity, the greater the increase in stability.     

Isolation and characterization of mutatoxanthin-epimers from red paprika (Capsicum annuum)

 (3S,5R,8R,3′R)- and (3S,5R,8S,3′R)-mutatoxanthin were isolated from red spice paprika (Capsicum annuum) and characterized by their UV-VIS, CD, ¹H-NMR, ¹³C-NMR and mass spectra. Received: 22 November 1999 / Revised version: 11 February 2000     

Characteristics of pigment composition and colour value by the difference of harvesting times in Korean red pepper varieties (Capsicum annuum, L.)

The main pigments of Capsicum annuum cv. Hanbando and Dabotop in dried red fruits were capsanthin, zeaxanthin, beta‐cryptoxanthin and beta‐carotene. Total carotenoid contents were twice as high at the fourth harvest compared with the second harvest in both varieties. The ratios of capsanthin to yellow fraction were above 1.0 in Hanbando and below 1.0 in Dabotop. Zeaxanthin content at the third harvest was about three times higher than at the second harvest in Dabotop. ASTA colour values harvested in the second, third and fourth weeks were 114, 152 and 178 in Hanbando and 115, 137 and 140 in Dabotop. Hue value of Hanbando was below 1.0 at all harvests and that of Dabotop was above 1.0 at the second and fourth harvests. The comparison of the C* values of two varieties revealed that Hanbando had the most vivid redness at the fourth harvest, whereas Dabotop was most vivid at the second harvest.     

Carotenoid loss in dried red pepper products

The carotenoid loss in dried red peppers, whole, and as coarse and fine powders, with and without seeds, was studied under various water activities, storage temperatures, and packaging atmospheres. Carotenoid loss of red pepper is affected by water activity, package atmosphere, storage temperature, and treatment of pepper. Nitrogen flushing or high water activity can increase carotenoid retention. To maintain good colour quality, both high carotenoid retention and low browning, red peppers should be stored in the form of coarse powder with seeds, at water activity below 0.3, and in a nitrogen atmosphere.     

Antioxidant constituents in some sweet pepper (Capsicum annuum L.) genotypes during maturity

Changes in total phenolics, antioxidant activity (AOX), carotenoids, capsaicin and ascorbic acid were monitored during three maturity stages in 10 genotypes of sweet pepper. In an attempt to explain the variations during maturity stages (green, intermediate and red/yellow), the data was expressed both on fresh and dry weight basis. All the antioxidant constituents (phenolics, ascorbic acid and carotenoids) and AOX, when expressed on fresh weight basis in general, showed an overall increasing trend during maturity in all the genotypes studied. On dry weight basis, phenolic content declined in majority of the genotypes during maturity to red stage. This decline was significant (P<0.05) in Parker, Torkel, HA-1038 and Flamingo. Genotype Flamingo and Golden Summer had the highest phenolic content of 852.0 mg 100 g⁻¹ and 720.5 mg 100 g⁻¹, at their final red and yellow maturity stages, respectively. With maturation, most of the cultivars showed a declining trend with regard to capsaicin content while total carotenoids and β-carotene content increased significantly. Anupam was a promising genotype in terms of both total carotenoids and β-carotene content. Ascorbic acid content declined progressively with advancing maturity. Genotype HA-1038 had the maximum content (3030 mg 100 g⁻¹ dwb) at the green stage. AOX in general, increased with maturity and registered a 1.30-1.95fold increase from green to red stage.The study proposes the nutritional significance of consuming sweet peppers at the red maturity stage because of enhanced functional properties. Overall genotype Flamingo and Anupam represent superior genotypes for both nutrition and germplasm improvement.     

Characterization of total capsaicinoids,colour and volatile compounds of Habanero chilli pepper (Capsicum chinense Jack.) cultivars grown in Yucatan

Total capsaicinoids, colour and volatile compounds of 10 Habanero chilli pepper (Capsicum chinense Jack.) cultivars grown in Yucatan, grouped by their colours: four red, five orange and one brown, were determined. The content of capsaicinoids, responsible for the pungency of chilli peppers, varied between 41.8 and 65.9 mg g⁻¹ dry fruit. Mean concentration of orange cultivars was 55.0 mg g⁻¹, while red cultivars had 45.0 mg g⁻¹ dry fruit, indicating that the first ones are more pungent. The composition of volatile compounds of the Habanero chilli peppers differs clearly for the different cultivars. Orange and brown cultivars have in general higher amounts of esters, with their fruity odour notes, than red cultivars. These differences are reflected in the amount of total volatiles, which is higher in orange and brown cultivars in comparison with red cultivars. From these results it can be concluded that orange and brown cultivars are better in terms of their flavour-relevant chemical composition than red cultivars.