Chemical characteristics of canarium salomonense oil

Canarium salomonense (ngali nuts) had an oil content of 736 g kg^?1 dry weight. The major fatty acids present were oleic (41–6%), palmitic (34–9%) and stearic (12–6% of the total fatty acids). The nuts produced a yellow oil which had a low free fatty acid content. The fatty acid composition of C salomonense is similar to palm oil and could be used as a general purpose cooking oil.     

Gelatin-chitosan edible film activated with Boldo extract for improving microbiological and antioxidant stability of sliced Prato cheese

The objective of this study was to produce edible gelatin-chitosan blended films containing Boldo extract, and then they were applied on sliced Prato cheese. Colour, pH, moisture and fat content parameters and antioxidant and antimicrobial activity were assessed, during storage at 4 °C up to 10 days. The films did not provoke changes in fat content and pH (P < 0.05). Boldo extract incorporation in blended films (GEL50:CH50+ B) enabled significant protection against oxidation when compared with the control sample, and it did not allow psychrotrophic microorganism growth, and a considerably low development of coliforms was shown in sliced Prato cheese samples.     

间接竞争ELISA法检测坚果类过敏原特异性研究

以腰果蛋白为过敏抗原,腰果蛋白致敏的阳性小鼠血清作为一抗,羊抗鼠Ig E-HRP为二抗建立双抗体间接酶联免疫吸附实验（ELISA）体系,通过棋盘法确定腰果蛋白最佳反应条件工作浓度为15.92μg/m L,最佳一抗稀释度均为1∶400,最佳酶标二抗的稀释度为1∶1000,腰果蛋白浓度为1.99μg/m L。并用该方法分别对腰果、核桃、榛子、开心果、板栗、杏仁等六种坚果进行检测分析,未发现有交叉反应,本实验建立的间接竞争性ELISA诊断方法具有良好的敏感性和特异性,为坚果过敏性食品的监测及时而准确的诊断奠定了基础。      

CHANGE OF FAT CONTENT AND FATTY ACID COMPOSITION OF TURKISH HAZELNUTS (CORYLUS AVELLANA L.) DURING STORAGE

Hazelnuts (Corylus avellana L.) were collected from three different cultivars (Tombul, Palaz and Kal?nkara) at the harvest season of 1996. The dried nuts were stored shelled and unshelled in polyethylene bags at 21C and 60–65% relative humidity for 12 months. During storage, the total fat content increased, the palmitic and oleic acid content of the oil increased, linoleic acid, ranged from 12.41 to 10.35%. No significant differences were found for other fatty acids during storage. The effect of storage of shelled and unshelled hazelnuts on the total fat content was significant.     

STABILITY OF OIL-IN-WATER EMULSIONS. 2. Effects of Oil Phase Volume, Stability Test, Viscosity, Type of Oil and Protein Additive

SUMMARY –Stability of oil-in-water emulsions stabilized in sodium caseinate, gelatin and soy sodium proteinate was found to be increased by either an increase in the aqueous phase protein concentration (0.5–2.5%) or oil phase volume (20–50%). Both factors were significantly interrelated. Emulsions stabilized by soy sodium proteinate were generally higher in stability as compared to those stabilized by gelatin or sodium caseinate. With emulsions containing gelatin, greater stability occurred when the stability testing temperature was increased from 37–70°C and when the time interval was decreased from 24 hr to 90 min. Maximum relative viscosities of emulsions stabilized by gelatin and sodium caseinate were 2.0 and 2.5, respectively. Emulsions stabilized by soy sodium proteinate were quite viscous, with relative viscosity from 1.5–30 depending on both protein concentration and oil phase volume. Interchanging the emulsified oil among corn, soybean, safflower and peanut oils did not alter emulsion stability when examined at three concentrations of soy sodium proteinate. Changing the oil to olive oil significantly increased emulsion stability at each soy sodium proteinate level with oil phase volumes of 30, 40 and 50%.     

坚果的主要生物活性成分及其保健作用

坚果作为高档零食,其营养价值和保健功能也越来越受到人们的关注?本论文综述了常见坚果(如澳洲坚果、核桃、榛子、杏仁、松子、板栗、山核桃、开心果,日本核桃、巴西坚果、花生等)中的酚类(原花青素、酚酸、黄酮、单宁、烷基酚、维生素E等)?酸类?甾醇类、色素(类胡萝卜素、叶绿素等)、硒、糖苷、功能性脂肪酸等营养物质和生物活性成分,并阐述了食用坚果与预防心血管疾病?延年益寿?预防糖尿病?控制体重等保健作用的关系?这对于进一步研究坚果与健康的关系、正确挑选与消费坚果均具有较好的指导意义。     

The compositional quality and volatile compounds of samples from the blend of monovarietal olive oils cultivated in Tunisia

Chemlali olive oil has been blended with oils obtained from Oueslati and Chetoui varieties to improve the quality of the former one. Parameters such as acidity, acids compositions, phenol content, oxidative stability and volatile compounds were characterised for various blends Chemlali × Oueslati and Chemlali × Chetoui. The accumulation of volatiles originating from the lipoxygenase pathway in the monovarietal oils was different and closely dependent on the genetic store of each variety. The concentrations appeared to proportionally vary according to the relative proportion of each monovarietal oil in the mixtures. The blending process improved fatty acids by increasing the oleic acid content and decreasing the palmitic and linoleic acids levels of Chemlali oil. At 40% blending, oleic acid increased from 54% to 62%, while palmitic acid decreased from 18.59% to 16% when Oueslati and Chetoui olive oil was used.     

Effect of calcium and sodium caseinates on physical characteristics of soy protein isolate–lipid films

The effect of addition of caseinates to soy protein isolated (SPI) based films containing lipids (33% of oleic acid or 85:15 oleic acid (OA)–beeswax blend (BW)) on water vapour permeability (WVP), mechanical and optical properties was evaluated. SPI–lipids was combined with caseinates (sodium or calcium) in different SPI:caseinate ratios with the aim of improving water vapour barrier, mechanical and optical properties of SPI films containing lipids. Caseinate incorporation to SPI based films provoked an increase of elastic modulus and tensile strength at break, mainly for calcium caseinate. Both caseinates contributed to increase the water vapour barrier properties of soy protein-based films. Caseinates also provoked an increase of transparency of SPI based films and colour softening. The most effective combination was 1:1 sodium caseinate:SPI ratio, when film contains 85:15 oleic acid:beeswax ratio.     

Brazil nuts and associated health benefits: A review

Epidemiological studies have shown an inverse relationship between nut intakes and chronic diseases such as cardiovascular diseases and cancers. The composition of lipids, minerals, and phytochemicals, and their associated health functions in Brazil nuts are critically reviewed. The nuts have high nutritive food value containing 60–70% oil and 17% protein. Brazil nuts contain abundant dietary antioxidants, especially selenium (Se). One single Brazil nut provides 160% of the US Recommended Daily Allowance (RDA) of selenium - perhaps the best source of Se from plant-based foods. Brazil nuts possess phenolics and flavonoids in both free and bound forms and are rich in tocopherol, phytosterols, and squalene. These compounds' possible beneficial effects are due to their antioxidant and antiproliferative activities, which are linked to a reduced risk for developing atherosclerosis and cancer.     

COMPOSITION OF DEHYDRATED PROTEIN EXTRACTS FROM POULTRY BONE RESIDUE

The composition of protein extracted from poultry bone residue by an alkali solution (pH 10 ± 0.05) and recovered by freeze-drying was determined. The dried extract contained approximately 60% protein. Calcium, phosphorus, magnesium, zinc, and lead were not substantially extracted from the bone residue; however, iron, copper, sodium, and potassium were concentrated by the process. SDS-PAGE patterns of the extracts were similar to poultry muscle tissue. The predominant amino acids in the extract were glutamic acid, aspartic acid, glycine, leucine, and lysine. Hydroxyproline was detected in the extract indicating the presence of collagenous material. The major fatty acids in the extract were oleic (38.7%), palmitic (23.1%), linoleic (15.3%), stearic (7.0%), and palmitoleic (6.77%) acid.     

Food-grade filled hydrogels for oral delivery of lipophilic active ingredients: Temperature-triggered release microgels

Delivery systems are often needed to encapsulate lipophilic active agents, protect them during storage, and then release them within the mouth. In this study, gelatin and caseinate were used to fabricate temperature-sensitive filled hydrogel particles. Filled hydrogel microspheres were formed by electrostatic complexation of caseinate and gelatin in the presence of caseinate-coated lipid droplets. This was achieved by mixing aqueous 1% sodium caseinate and 1% gelatin solutions (volume ratio 1:2) at pH 5.8 with an oil-in-water emulsion. The majority of lipid droplets were trapped within the hydrogel microspheres. Turbidity and viscosity measurements of the hydrogels indicated that hydrogel particles dissociated upon heating because of gelatin melting (around 35 °C). Light scattering and confocal fluorescence microscopy indicated that lipid droplets were released from the gelatin-based hydrogel particles after oral processing, which was attributed to hydrogel melting under simulated mouth conditions. Our results suggest that hydrogel particles based on electrostatic complexation of sodium caseinate and gelatin could be useful as oral delivery systems for lipophilic active agents.     

Effect of γ-irradiation on the physicochemical and sensory properties of cashew nuts (Anacardium occidentale L.)

The present study evaluated cashew nuts' quality as a function of γ-irradiation dose in order to determine dose levels causing minimal undesirable changes to the product. Physicochemical (colour, peroxide value, hexanal content, fatty acid composition, volatile compounds) and sensory (colour, texture, odor, taste) properties of cashew nuts were determined after irradiation at doses up to 7 kGy. Results showed a five-fold increase in peroxide value (PV) and a two-fold increase in hexanal content after irradiation at a dose of 7 kGy. Of the fatty acids determined, stearic acid concentration increased while oleic acid decreased with irradiation dose. PUFA were unaffected by irradiation. Volatile compounds such as aldehydes, ketones and alcohols increased after irradiation indicating enhanced lipid oxidation. Colour parameter a∗ increased (p < 0.05) at doses >3 kGy while colour parameters L∗ and b∗ remained unaffected by irradiation. Sensory analysis showed that cashew nuts remained organoleptically acceptable at doses <3 kGy.     

Effect of gamma irradiation on the physico‐chemical and sensory properties of raw shelled peanuts (Arachis hypogaea L.) and pistachio nuts (Pistacia vera L.)

Backround The present study evaluated the quality of raw peanuts and pistachio nuts as a function of irradiation dose in order to determine dose levels causing minimal undesirable changes to these products. Physico‐chemical (colour, peroxide value, hexanal content, fatty acid composition, volatile compounds) and sensory (colour, texture, odour, taste) properties of raw peanuts and pistachio nuts were determined after irradiation at doses up to 7 kGy. Results Results showed an eight‐ and seven‐fold increase in peroxide value and a twelve and five‐fold increase in hexanal content after irradiation at a dose of 7 kGy for peanuts and pistachio nuts, respectively. An increase was also observed in saturated fatty acids (20.51–28.28% and 15.24–24.87%) with a parallel decrease in unsaturated fatty acids (79.49–71.72% and 84.76–75.13%) for peanuts and pistachio nuts, respectively. Likewise, volatile compounds such as aldehydes, alkanes, ketones and alcohols comprising secondary oxidation products of peanut and pistachio nut lipids increased after irradiation. Pistachio nut colour parameter a* and to a lesser extent parameters, L* and b* decreased after irradiation leading to a slight but noticeable darkening in product colour while colour parameter L*, b* and a* of raw peanut remained unchanged by irradiation up to 7 kGy. Conclusion Based on sensory evaluation, peanuts and pistachio nuts become unacceptable for consumption when irradiated at doses higher than 3 kGy. Copyright © 2009 Society of Chemical Industry     

Barrier properties of sodium caseinate films as affected by lipid composition and moisture content

This work analyses the effect of lipid addition (oleic acid, beeswax and oleic acid-beeswax mixtures) as well as the influence of the relative humidity (RH), or the equilibrium water content of the films, on the permeability of sodium caseinate based films to water vapor and gas (oxygen and carbon dioxide). The effect that lipid addition had on the gas and water vapor permeability was dependent both on the composition of oleic acid-beeswax mixtures and the film’s moisture content. The addition of lipid mixtures reduced water vapor transfer as compared to the control films (without lipid), whereas pure oleic acid or beeswax were less effective. Both control films and films prepared with pure beeswax showed the lowest O₂ and CO₂ permeability, whereas the incorporation of oleic acid exponentially increased these values. A linear increase in water vapor and gas permeability was observed when the water content of the film rose, due to its plasticizing effect, which led to an increase in the molecular mobility. Predictive equations for water vapor permeability (WVP) and gas permeability were established as a function of water content and lipid composition.     

Compositional analysis and roasting behaviour of gevuina and macadamia nuts

This study compares the composition of macadamia and gevuina nuts following natural abscission and air-drying of intact nuts and compares chemical and sensory properties on roasting gevuina nuts using a reported macadamia roasting process. The markedly higher fat content of macadamia (75% vs. 43%) reflected a higher percentage of protein, moisture, ash and carbohydrate in gevuina nuts. Gevuina nuts also had lower energy and pH values than macadamia. Water activities were similar. Both oils were around 80% monounsaturated, but differed widely in positional isomerism. On roasting, macadamia nuts developed sweet, nutty, buttery notes along with brown colour development (measured using L *, a *, b * values) after 20 min at 135 °C while gevuina nut colour and aroma took at least 30 min, where the aroma was more hazelnut-like. Extractable volatiles were significantly higher for macadamias following roasting.     

响应面法优化南极磷虾油微胶囊喷雾干燥制备工艺的研究

为提高南极磷虾油微胶囊化率,降低南极磷虾油微囊化利用成本,以酪蛋白酸钠、明胶、麦芽糊精为壁材,采用喷雾干燥法对南极磷虾油进行微胶囊化包埋,利用单因素实验结合响应面优化包埋工艺,并对微胶囊化后产品的理化性质进行研究。结果表明:酪蛋白酸钠质量分数为24.55%、明胶质量分数为4.86%、芯壁质量比为0.33,麦芽糊精质量分数为45.60%,南极磷虾油微胶囊包埋率为93.79%。微胶囊水分含量2.31%±0.12%,吸湿性强,灰分含量为2.04% ± 0.14%,微胶囊粒径集中在14.8～26.7 μm。响应面法预测各因素对南极磷虾油微胶囊包埋率的影响大小关系为:芯壁质量比>明胶>酪蛋白酸钠。机械强度试验表明,在不同的pH环境和离心时间条件下,微胶囊中南极磷虾油释放率小于0.3%,微胶囊结构非常稳定。     

绍兴香榧坚果品质变异分析及综合评价

为了解绍兴香榧品质情况,提高香榧品质及商品价值,对来自绍兴香榧核心产区12 个香榧样品的21 个外 在和内在指标变异情况进行研究,并对其变异情况及坚果综合品质进行了主成分分析和聚类分析。结果表明：香 榧外观及内在品质各指标差异显著。香榧样品种仁平均油脂质量分数为50.28%,蛋白质平均含量为12.70 g/100 g, 而且不同产区之间差异皆显著（P＜0.05）;香榧种仁不饱和脂肪酸所占比例在60.08%～75.77%,主要为油酸和 亚油酸。经综合评价及聚类分析可知,嵊州的香榧综合评价值最高,其次依次为诸暨的香榧和绍兴稽东的香榧。 种子长度、油脂质量分数、种子质量、蛋白质含量、油酸和亚油酸质量分数是评价香榧品质质量的重要指标。综 合评价分析表明坚果品质综合表现较优的为嵊州香榧。综上,利用主成分分析和聚类分析可以对香榧坚果品质进 行评价和其简化。     

Conjugated linoleic acid production by cells and enzyme extract of Lactobacillus delbrueckii ssp. bulgaricus with additions of different fatty acids

The objective of the study was to determine the effect of fatty acid additions to the cells and enzyme extract of Lactobacillus delbrueckii ssp. bulgaricus (CCRC14009) on CLA production. Washed cells of L. delbrueckii ssp. bulgaricus, obtained by cultivation in a MRS broth, were mixed with BSA and each of the three fatty acids: linoleic, oleic, and linolenic acids in sodium phosphate buffer at pH 6.5. After incubation at 37 °C for 108 h, CLA concentration was analyzed by HPLC. Enzyme extract from the culture was also reacted with each fatty acid at 50 °C for 10 min at pH 5 to test for CLA production. Results showed that linoleic acid addition to the culture improved CLA production, indicating the presence of linoleic acid isomerase activity in the culture. The crude enzyme extract from the culture was observed to be capable of oleic and linolenic acid conversions into CLA, demonstrating the possible presence of desaturase activity in the enzyme extract.     

EFFECT OF PROCESSING ON SOME CHEMICAL CONSTITUENTS OF PISTACHIO NUTS

The effect of processing on changes in fatty acids, sugars and amino acids in pistaschio nuts during blanching, drying and roasting was monitored. Blanching in hot water led to some loss in fatty acids, sugars and amino acids. Roasting further decreased the availability of the constituents. The magnitude of loss of the constituents was in the following order: blanching > roasting > drying. The composition profile of each of the constituents was analyzed. There was variation in the distribution of fatty acids among the raw and processed nuts. Unsaturated fatty acids were more susceptible to changes during processing. The combined loss of oleic and linoleic acids amounted to 22.29% of that present in the raw nuts. Fructose, glucose, sucrose and raffinose were shown to be present in the nuts. The loss of sucrose was higher than the monosaccharides during processing. Glutamic acid, leucine, proline 56.50% of the amino acids present, and blanching, drying and roasting successively caused losses in the availability of these amino acids. The effect of processing on nutritional values has been a subject of concern to consumers and food processors. The present investigation reveals that the loss in various components in the nuts deserves more attention.     

Influence of calcium on tensile, optical and water vapour permeability properties of sodium caseinate edible films

The influence of calcium on sodium caseinate edible films with and without lipid addition (oleic acid (OA)–beeswax (BW) mixtures) was investigated through the analysis of tensile, optical and water vapour barrier properties. Calcium was added by substitution of sodium caseinate by calcium caseinate. Calcium caseinate films have less transparency and more rigidity but they have lower water vapour permeability values than sodium caseinate films. The effect of substitution was different for films with and without lipids. Calcium caseinate increased tensile strength and decreased elongation of films, depending on the level of substitution and lipid presence. Among control films (without lipid), water vapour permeability was reduced when calcium caseinate was present, reaching values of 3.9 (±0.2) g mm kPa⁻¹ h⁻¹ m⁻². Nevertheless, in the films containing lipids, this reduction was inhibited when the level of sodium caseinate substitution exceeded 50%. Film transparency and gloss was reduced by calcium caseinate and lipid presence, although pure calcium caseinate films were glossier. When taking all the studied variables into account, the films prepared with 2:1 NaCas:CaCas ratio and 70:30 OA:BW ratio showed the most adequate properties.