Characterisation of musk lime (Citrusmicrocarpa) seed oil

BACKGROUND: The seeds of musk lime (Citrus microcarpa) represent a substantial waste product of small‐scale citrus‐processing factories, as they constitute about 100.0 ± 3.2 g kg^?1 of the whole fruit and contain a considerable amount of crude fat (338.0 ± 11.3 g kg^?1). Thus the aim of the present study was to determine the physicochemical properties of this fat with a view to potential applications. RESULTS: The iodine and saponification values and unsaponifiable matter and free fatty acid contents of the freshly extracted oil were 118.0 g I₂ per 100 g oil, 192.6 mg KOH g^?1 oil, 22 mg g^?1 oil and 18 mg oleic acid g^?1 oil respectively. The oil had a Lovibond colour index of 33.1 Y + 1.1 B. Its fatty acid profile indicated that 73.6% of the fatty acids present were unsaturated. Linoleic (L, 31.8%), oleic (O, 29.6%) and palmitic (P, 21.4%) acids were the predominant fatty acids, existing mainly as the triacylglycerols POL (18.9%), PLL (13.7%) and OLL (11.9%). The melting and cooling points of the oil were 10.7 and ? 45.2 °C respectively. Electronic nose qualitative analysis of the oil showed the presence of volatile (aroma) compounds, although the concentrations of the more volatile compounds were lower than those present in the seeds. CONCLUSION: Musk lime seeds are a rich source of oil, which is unusual in having linoleic, oleic and palmitic acids dominating the fatty acid composition. This property should make the oil both relatively stable to thermal oxidation owing to the combined presence of oleic and palmitic acids (61.0%) and highly nutritive owing to its high concentration of unsaturated fatty acids (73.6%). Copyright © 2007 Society of Chemical Industry     

The responses of two genotypes of white clover to addition of lime to an acid permanent grassland soil

The response of white clover to addition of lime was studied in pots with an acid permanent grassland soil (pH 4.1), and a comparison made between a commercial cultivar (Blanca) and a white clover indigenous to the acid soil. The yield of both plants increased markedly with addition of lime, but the native genotype reached maximum yield at a lower pH. In both cases, however, only relatively small adjustments of pH were required to produce considerable increases in yield. The addition of lime reduced the amounts of Al and Mn extracted by 1M ammonium acetate and 0.01M CaCl₂, and increased exchangeable Ca. It was suggested that, although plant contents of Mn were high and those of Ca low, the effect of lime was not on the clover plant per se but on nodulation and the supply of N through symbiotic fixation. When no lime was added, both plants contained concentrations of N below that suggested as critical, and had only limited numbers of nodules on their roots. Excess Al and/or Mn, or insufficient Ca may have been responsible for inhibition of nodulation at the low pH of the unlimed soil. Although the indigenous plant also grew poorly when no lime was added, it displayed a number of characteristics which may assist its performance and persistence under acid conditions in the field.     

Pectinesterase extraction from Mexican lime (Citrus aurantifolia Swingle) and prickly pear (Opuntia ficus indica L.) peels

Extracts from Mexican lime (Citrus aurantifolia Swingle) and prickly pear (Opuntia ficus indica L.) peels were tested for their pectinesterase activity. A factorial design was applied in this study as a method for enzyme extraction in which the variables were the source of enzyme (prickly pear and Mexican lime peels) and the NaCl solution concentration (0–3.0 M). In all cases, enzyme extracts obtained using the same NaCl concentration from lime peel showed higher activity than extracts from prickly pear peel. NaCl concentration influenced the pectinesterase extraction process in both cases. Maximum enzyme activities were obtained with NaCl 0.5 M and 1.0 M for Mexican lime and prickly pear peels, respectively.     

Effects of Tropical Citrus Essential Oils on Growth, Aflatoxin Production, and Ultrastructure Alterations of Aspergillus flavus and Aspergillus parasiticus

Ethyl acetate extracts and hydrodistillated essential oils from five cultivars of tropical citrus epicarps were evaluated for their inhibitory activities against Aspergillus fumigatus, Aspergillus niger, Aspergillus flavus, Aspergillus parasiticus, and Penicillium sp. using disk diffusion and broth microdilution assays. Essential oils prepared from kaffir lime (Citrus hystrix DC) and acid lime (Citrus aurantifolia Swingle) epicarps exhibited stronger antifungal activity to all fungi than their ethyl acetate extracts with minimum inhibitory concentration and minimum fungicidal concentration values of 0.56 and 1.13 mg/ml (dry matter), respectively, against aflatoxin-producing A. flavus and A. parasiticus. The dominant components of the essential oil from kaffir lime were limonene, citronellol, linalool, o-cymene, and camphene, whereas limonene and p-cymene were major components of acid lime essential oil. Pure limonene, citronellal, and citronellol were five to six times less fungicidal than the natural essential oils, indicating the synergistic activity of many active compounds present in the oils. Kaffir and acid lime essential oils significantly reduced aflatoxin production of A. flavus and A. parasiticus, particularly lime essential oil, which completely inhibited growth and aflatoxin production of A. flavus at the concentration of 2.25 mg/ml. Target cell damage caused by acid lime essential oil was investigated under transmission electron microscopy. Destructive alterations of plasma and nucleus membrane, loss of cytoplasm, vacuole fusion, and detachment of fibrillar layer were clearly exhibited in essential-oil-treated cells.     

Analysis and characterization of aroma‐active compounds of Schizandra chinensis (omija) leaves

Volatile components from leaves of Schizandra chinensis (omija), a native plant of Korea, were extracted by simultaneous distillation–extraction (SDE) and analyzed by gas chromatography–mass spectrometry (GC‐MS) using two types of capillary column with different polarities (DB‐5MS and DB‐Wax). The GC‐MS analysis of volatile compounds obtained by SDE revealed that germacrene D is the most abundant compound (22.6%) in omija leaves, followed by β‐elemene (17.4%), (E)‐2‐hexenal (8.7%), and (E)‐β‐ocimene (7.2%). Aroma‐active compounds were determined by gas chromatography–olfactometry (GC‐O) using the aroma‐extract‐dilution analysis method. (E,Z)‐2,6‐Nonadienal (cucumber) was the most intense aroma‐active compound due to its higher flavor‐dilution factor (243–729) than any other compound. (Z)‐3‐Hexenal (green/apple), (E)‐2‐hexenal (green/fruity), and (E)‐β‐ocimene (wither green/grass) were also identified as important aroma‐active compounds by GC‐O. In addition, the volatile compounds were extracted by solid‐phase microextraction (SPME), and the quantitative analysis of the SPME samples gave slightly different results, depending on the type of SPME fiber, compared with those from SDE, However, the aroma‐active compounds identified in SPME were similar to those in SDE. Copyright © 2004 Society of Chemical Industry     

Quantitative composition of volatile constituents in cultivated strawberries,Fragaria ananassa cv. senga sengana,senga litessa and senga gourmella

The volatile components of cultivated strawberries Fragaria ananassa cv. Senga Sengana, Senga Litessa and Senga Gourmella were studied by gas chromatography-mass spectrometry. Employing standard-controlled aroma separation by combined vacuum distillation-liquid-liquid extraction, as well as prefractionation on silica gel, the aroma substances of freshly harvested and deep-frozen strawberries from two growing seasons were quantitatively determined by gas chromatography. Methyl and ethyl butanoate, methyl and ethyl hexanoate, trans-2-hexenyl acetate, trans-2-hexenal, trans-2-hexen-1-ol as well as 2,5-dimethyl-4-methoxy-3(2H)-furanone were identified as main volatile components. In comparison to Senga Litessa and Senga Gourmella, Senga Sengana showed higher amounts of aroma compounds. In general, deep-freezing resulted in decreases of the concentrations of most of the aroma substances, but higher amounts of 2,5-dimethyl-4-methoxy-3(2H)-furanone were found in deep-frozen berries than in the freshly harvested ones.     

Comparative study on the antioxidant capacity and cholinesterase inhibitory activity of Citrus aurantifolia Swingle, C. aurantium L., and C. bergamia Risso and Poit. peel essential oils

Abstract: The interest in medicinal plant research and in the aroma‐therapeutic effects of essential oils in humans has increased in recent years, especially for the treatment of pathologies of relevant social impact such as Alzheimer's disease. The present study was taken up to evaluate the antioxidant capacity and the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity of the peel essential oils from three Citrus species, C. aurantifolia Swingle, C. aurantium L., and C. bergamia Risso & Poit. Essential oils were analyzed by GC and GC‐MS and they contain mainly limonene, α‐pinene, β‐pinene, γ‐terpinene, and linalyl acetate. C. aurantifolia oil showed the highest radical scavenging activity on ABTS assay (IC₅₀ value of 19.6 μg/mL), while C. bergamia exhibited a good antioxidant activity evaluated by the β‐carotene bleaching test (IC₅₀= 42.6 μg/mL after 60 min of incubation). C. aurantifolia inhibited more selectively AChE. Obtained data suggest a potential use of Citrus oils as a valuable new flavor with functional properties for food or nutraceutical products with particular relevance to supplements for the elderly. Practical Application: The demonstrated antioxidant activity and procholinesterase properties of Citrus essential oils suggested their use as a new potential source of natural antioxidant to added as extra‐nutrient for using in food industries as a valuable new flavor with functional properties for food or nutraceutical products with particular relevance to supplements for the elderly.     

Effect of selected aromatic medicinal plant sancho (Zanthoxylum schinifolium) on osteoblastic MC3T3-E1 cells

This study was performed to investigate the bioactivity of sancho (Zanthoxylum schinifolium) essential oil (EO) on bone metabolism and its function of osteoblastic MC3T3-E1 cells. The volatile aroma components of sancho EO were collected using a Clevenger-type apparatus by steam distillation extraction method, and determined by GC-MS. β-Phellandrene (22.54%) was the most abundant volatile compound in sancho EO, followed by citronellal (16.48%) and geranyl acetate (11.39%). It increased the collagen and mineralization of osteoblasts (p<0.05), indicating that sancho may help prevent osteoporosis.     

Growth and fermentation kinetics of a mixed culture of Saccharomyces cerevisiae var. bayanus and Williopsis saturnus var. saturnus at different ratios in longan juice (Dimocarpus longan Lour.)

Cofermentation of longan juice by mixed cultures of Saccharomyces cerevisiae var. bayanus EC‐1118 and Williopsis saturnus var. saturnus CBS254 at two inoculation ratios (EC‐1118:CBS254 = 1:100 and 1:1000 cfu mL^?1) was performed to ascertain their impact on longan wine aroma compound formation. The results showed improved aroma compound profiles in the longan wine fermented with mixed yeasts in comparison with the longan wines fermented with single yeasts in terms of increased production of acetate esters, fatty acid ethyl esters, alcohols and carboxylic acids. The impact of cofermentation on longan wine aroma formation was affected by the ratio of S. cerevisiae EC‐1118 to W. saturnus CBS254 with 1:100 cfu mL^?1 being more effective. This research suggests that the inoculation ratio of mixed yeasts may be used as an effective means of manipulating longan wine aroma.     

Volatile flavour compounds in suspension culture of Agastache rugosa Kuntze (Korean mint)

For the production of volatile flavour compounds from Agastache rugosa Kuntze (Korean mint) suspension culture, callus was obtained from the leaves of A rugosa. Cell growth of A rugosa suspension culture was improved when cells were cultivated in Murashige and Skoog medium supplemented with 50 g l^?1 sucrose and 1 mg l^?1 2,4‐dichlorophenoxyacetic acid. Volatiles were isolated from a 15‐day‐old suspension culture by liquid–liquid continuous extraction and identified by gas chromatography/mass spectrometry. 3‐Hydroxy‐2‐butanone was the most abundant compound, followed by 2,4,5‐trimethyl‐3‐oxazoline, 1,2,4‐trimethylbenzene and 1,3‐butanediol. However, the volatile profile of the suspension culture was totally different from that of the intact plant. Fourteen aroma‐active compounds were detected by aroma extract dilution analysis. The most potent aroma‐active compounds representing characteristic aroma of A rugosa suspension culture were 2,3‐butanedione (buttery/cheese), (E,Z)‐2,6‐nonadienal (cucumber/melon) and (E,Z)‐2,6‐nonadien‐1‐ol (cucumber/sweet). Some alcohols and unknown compounds are thought to contribute to the wine‐like aroma characteristics of A rugosa suspension culture. Through a time course study, A rugosa suspension culture was revealed to have an inverse relationship between cell growth and flavour production. © 2001 Society of Chemical Industry     

Volatile composition of wines from cvs. Blanco lexítimo,Agudelo and Serradelo (Vitis vinifera) grown in Betanzos (NW Spain)

Wine aroma is formed by volatile compounds of different chemical natures and origins. Betanzos is the most northern viticole geographic area from Galicia (NW Spain). The aromatic profiles of wines produced from two white varieties (Blanco lexítimo and Agudelo) and one red variety (Serradelo) from Betanzos, harvested in 2006 and 2007, have been established by gas chromatography (GC/FID). A total of 35 varietal and fermentative aroma compounds were identified and quantified in free volatile form, which include terpenols, C₁₃‐norisoprenoids, alcohols, esters, volatile fatty acids and volatile phenols. To ascertain the compounds with major impact odours, the Odour Activity Value (OAV) was calculated. Twelve compounds showed concentrations above their perception threshold (OAV>1). The results obtained suggest that ethyl octanoate (apple), isoamyl acetate (banana), ethyl hexanoate (fruity) and β‐damascenone (floral) were the most powerful odorants for the white wines Blanco lexítimo and Agudelo from Betanzos. Ethyl octanoate and β‐damascenone (fruity and floral aroma respectively) were the most odorant for the red wine Serradelo.     

Influence of spray‐dryer air temperatures on encapsulated lime essential oil

The influence of inlet and outlet air temperatures (180–220 and 80–100 °C, respectively) on the spray drying of lime essential oil was evaluated by using a three‐level factor design. For optimisation, dryer evaporative rate, volatile oil retention, and microencapsulation efficiency were considered as response variables. The response surface analysis produced significant (P < 0.05) polynomial regression equations that were successfully fitted for all response variables, and no significant (P > 0.05) lack of fit was indicated for the reduced models, with the exception of microencapsulation efficiency. This observation confirmed an accurate fitness of the reduced response surface models to the experimental data. The multiple response optimisations indicated that an inlet air temperature of 220 °C and an outlet air temperature of 85 °C were predicted to provide the maximum evaporative rate (7.7 kg h^?1), volatile oil retention (95.7%), and microencapsulation efficiency (99.9%) in the studied ranges. Checking of the optimisation showed that with these optimal parameters, a very good closeness between the experimental and predicted values was obtained.     

Dissolvable and edible film for long-lasting kaffir lime aroma in food

A dissolvable and edible carboxymethylcellulose–alginate film with 34% (w/w) of kaffir lime oil (KLO) was prepared. The prepared films can be redissolved in warm water providing highly dispersed KLO microdroplets. The freshly prepared KLO films (KLO film-0) and 6-month stored KLO films (KLO film-6) were evaluated for consumer acceptance in a Thai Tom-yum soup recipe in comparison with fresh kaffir lime (KL) leaves and commercialised instant Tom-Yum paste. The data analysis from 120 consumers presented the higher liking scores of the soups using the KLO film-0 and KLO film-6 on aroma, taste and overall preference than those using the instant Tom-Yum paste and the KL leaves. Additionally, chefs noted a longer lasting aroma intensity of the soups prepared with KLO films. Thus, this edible KLO film can be used in place of fresh KL leaves with the additional benefits of a long shelf-life, ease of use and better consumer preferences in Tom-Yum soup cooking.     

Effect of drying methods on volatile compounds,fatty acids and antioxidant property of Thai kaffir lime (Citrus hystrix D.C.)

This study investigated the changes in colour, volatile compounds, fatty acids, total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity of kaffir lime leaves (makrud in Thai) Citrus hystrix D.C. after three drying treatments, namely hot‐air (HA) drying, low relative humidity (LRH) air drying and far‐infrared radiation (FIR) drying. Overall, when compared with fresh leaves, a slight decrease in L* values of the three dried samples was observed. TPC, TFC and ferric‐reducing/antioxidant power (FRAP) values were increased by LRH and FIR drying (LRH: 39%, 43% and 28%; FIR: 62%, 39% and 39%), while HA drying decreased TPC, TFC and FRAP values (28%, 21% and 1%), compared with fresh leaves. The main volatile compounds in fresh leaves were citronellal, followed by linalool and viridiflorol. Drying brought about an increase in the concentrations of volatile components, such as citronellal with HA, LRH and FIR drying (79%, 83% and 64%, respectively), compared with the results for fresh leaves (56%). LRH and HA drying increased essential fatty acid alpha‐linolenic acid (ALA, 18:3n‐3), while linoleic acid (LA, 18:2n‐6) was increased by FIR drying. The present study has provided useful information for the industrial use of dried kaffir lime production.     

Analysis of Persian lime essential oil

Commercially produced Persian lime essential oil was qualitatively and quantitatively analyzed by GC-MS. The oxygenated components represent 25% of the total composition. The major and most of the minor components we isolated from essence oil had been previously identified from coldpressed oil or aqueous essence. Three minor components, 3-methyl-2-butanol, trans carvyl and cis carvyl acetate, not previously found in lime, were identified in this study.     

白柠檬果皮油特征香气成分的评价

用客观方法 ,评价了白柠檬果皮油的特征香气成分。用溶剂萃取法提取白柠檬果皮的精油 ,并用硅胶柱将精油分成碳氢化合物和含氧化合物两大部分 ,由于含氧化合物部分具有果皮油的特征香气 ,利用各成分的香气值对该部分进行了评价 ,明确了香叶醛、橙花醛、沉香醇以及一些脂肪族醛等 2 5种成分对白柠檬果皮油香气起着重要作用。用这些成分按着在果皮油中的含量比调配成的混合液具有白柠檬果皮的香气。由此可知 ,利用香气成分的香气值 ,能够筛选出对食品的香气起重要作用的成分。     

Volatile composition and key flavour compounds of spirits from unifloral honeys

The volatile components of industrially produced spirits from three unifloral honeys of campanilla morada (Ipomoea crassicaulis [Benth.] B.L. Robinson), citrus (Citrus spp. L.) and romerillo de costa (Viguiera dentata [Cav.] Spreng.) were studied by combined sensory and instrumental techniques. GC and GC‐MS analyses of the isolated extracts led to the detection of 205 volatile compounds, 150 of them were positively identified. In general, the most abundant classes were saturated alcohols, ethyl esters of saturated fatty acids and terpenes in all samples. Relative aroma intensity of individual volatile components was evaluated by aroma extract dilution analysis of solvent extracts, by gas chromatography‐olfactometry and by odour activity values. Results indicated that 11 compounds: ethanol, ethyl esters of isopentanoic, hexanoic, octanoic and decanoic acids, 2‐phenylethyl acetate, (E)‐β‐damascenone, hotrienol, decanal, methyl anthranilate and ethyl (E)‐cinnamate were the most potent odorants in the honey spirits.     

Artificial neural network modeling of mass transfer during osmotic dehydration of kaffir lime peel

Mass transfer of kaffir lime peel during osmotic dehydration was investigated in this paper. Processing factors were solute concentrations, process temperatures, and immersion time. The results showed that increasing solute concentration and process temperature resulted in a higher reduction in moisture contents of kaffir lime peel and increase in water loss and solid gain rates. Analysis of variance showed significant effects (P < 0.05) of all processing factors except process temperatures for water loss. Multilayer feedforward neural network (MFNN) was proposed to predict percentages of water loss and solid gain of kaffir lime peel during osmotic dehydration based on three processing factors as inputs. The best network with the lowest average mean squared error (MSE) of 0.0066 and the highest average regression coefficient (r²) of 0.9725 from normalized training and validating data sets was composed of one hidden layer with five hidden neurons and used Levenberg–Marquardt algorithm as a training algorithm. A simulation test showed good generalization of the successfully trained MFNN model with the average MSE of 6.5813 and 5.9340, and average r² of 0.9745 and 0.9632, respectively, for water loss and solid gain. Compared with multiple linear regression models, MFNN was found to be more suitable for predicting water loss and solid gain during the OD process of kaffir lime peel.     

Volatile flavour components of grapefruit juice (Citrus paradisi Macfadyen)

The qualitative analysis of volatile flavour components in grapefruit juice (Citrus paradisi Macfadyen) was performed using a gas chromatography/mass spectro-metry/computer system which allowed the identification of 58 components, 25 of them being reported for the first time. The aroma concentrates were obtained by an efficient simultaneous steam distillation/solvent extraction method which made it possible to identify many trace aroma components. Only quantitative differences were found in the aroma composition of fresh grapefruit juice extracted from different fruit batches of the same geographic origin during one season.