Effect of high-oleic trait and paste storage variables on sensory attribute stability of roasted peanuts

There has been much interest in the effect of the high-oleic acid trait of peanuts on various quality factors since discovery of high levels of oleic acid in a peanut mutant genotype. The trait provides greater oxidative stability for the high-oleic oil and seed. Several research groups have investigated high-oleic peanut oil and roasted peanut flavor characteristics, which were similar within high-oleic lines compared to Florunner. It was observed that some high-oleic lines derived from the Sunrunner cultivar have consistently higher predicted breeding values for roasted peanut attribute than Sunrunner itself. This study investigated if this apparent effect of the trait was an artifact arising from the handling procedures during processing and storage or from flavor fade. High-oleic lines used were derived by backcrossing the trait into existing cultivars, and the comparison of sensory attribute intensity was with the recurrent parent used in backcrossing. Previous comparisons have been between lines differing in more than just oleate content, that is, with widely different background genotypes that could contribute to the differences observed. Differential rates of change in sensory attributes were found in different background genotypes, suggesting that the comparison of high- and normal-oleic lines should be made in common background genotypes as well as in common production and postharvest environments. There was no measurable change in roasted peanut attribute in samples stored at -20 degrees C over the 63 day duration of this experiment. There were changes in roasted peanut in samples stored at 22 degrees C, confirming that storage at -20 degrees C is sufficient for large studies that require multiple sensory panel sessions over a period of weeks.     

Sensory attribute variation in low-temperature-stored roasted peanut paste

Length of sample storage can become significant in sensory studies due to panel fatigue limitations and samples needed for a reasonable expectation of finding significant differences. In roasted peanut sensory studies samples are stored between -10 and -23 degrees C to prevent or retard changes. Studies of up to 13 months' duration have examined stability and slow-rate sensory changes. Sweet taste was relatively stable, whereas bitter and tongue burn attributes increased slightly. Stale taste increased, suggesting lipid oxidation was taking place even at -23 degrees C. Painty attribute did not increase until stale was >3. An increase in fruity attribute was unexpected. With increases in fruity and stale attributes a decrease in roasted peanut was expected. However, storage at -23 degrees C seems to stabilize the roasted peanut lability when compared to storage at -10 degrees C. Fruity and stale interactions with roasted peanut and lability of roasted peanut were shown to be three separate and identifiable effects on roasted peanut.     

湿涝胁迫对不同种质花生生长和农艺性状的影响

研究了花生营养生长末期至开花期根部淹没处理对18个不同耐涝性品种的影响.结果表明, 湿涝使多数花生品种株高降低, 单株分枝数、总果数与饱果数减少, 而果、仁生长得以促进且饱满度提高.经过湿涝处理后, 基于性状变化的品种聚类分析结果与基于产量变化的品种耐涝性分类有较高统一性(18个品种可归类为6个性状变化类型), 又有一定差异性, 即多数湿涝敏感品种的果、仁数量或重量性状不同步变化, 而经过湿涝生态压力选择选育的绝大多数耐性品种表现为株型变小, 果、仁数量或重量性状同步增长, 且饱果数率、饱果重率提高.说明耐湿涝生态育种是有成效的.在需水较多的生育期(营养生长末期至开花期), 只要有流水通过且花生植株顶部不被淹没, 湿涝的影响是有限的, 对多数耐涝品种甚至可促进果仁发育.因此, 对花生受洪涝灾害影响的评估, 应因湿涝程度、发育时期、品种耐性而异.     

Allergenic properties of roasted peanut allergens may be reduced by peroxidase

Peanut allergy is a public health issue. The culprits are the peanut allergens. Reducing the allergenic properties of these allergens or proteins will be beneficial to allergic individuals. In this study, the objective was to determine if peroxidase (POD), which catalyzes protein cross-linking, reduces the allergenic properties of peanut allergens. In the experiments, protein extracts from raw and roasted defatted peanut meals at pH 8 were incubated with and without POD in the presence of hydrogen peroxide at 37 degrees C for 60 min. The POD-treated and untreated samples were then analyzed by SDS-PAGE, western blots, and competitive inhibition ELISA. IgE binding or allergenicity was determined in blots and ELISA. Results showed that POD treatment had no effect on raw peanuts with respect to protein cross-linking. However, a significant decrease was seen in the levels of the major allergens, Ara h 1 and Ara h 2, in roasted peanuts after POD treatment. Also, polymers were formed. Despite this, a reduction in IgE binding was observed. It was concluded that POD induced the cross-linking of mainly Ara h 1 and Ara h 2 from roasted peanuts and that, due to POD treatment, IgE binding was reduced. The finding indicates that POD can help reduce the allergenic properties of roasted peanut allergens.     

Sodium azide induced high-oleic peanut (Arachis hypogaea L.) mutant of Virginia type

Less prone to oxidation than its conventional counterpart, high-oleic peanut (Arachis hypogaea L.) containing?≥?72% oleate and?<?8% linoleate is preferred by processors, seed sellers and consumers. Development of high-oleic peanut cultivars with suitable pod/seed size and shape may satisfy the need from food processors manufacturing whole kernel or halve products. In this study, a high-oleic Virginia type peanut mutant was identified through screening of a 15 mmol/L sodium azide mutagenized M3 population with near infrared spectroscopy. Sequencing of the mutated and wild type FAD2A/FAD2B genes detected 2 point mutations. The G448A mutation in FAD2A was the same as in previous reports, causing an amino acid change of D150N. G558A in FAD2B was a novel mutation, resulting in a stop codon and premature termination of protein synthesis. 16 promising lines with acceptable productivity and pod/seed characters have been tentatively bred, which will be evaluated further in yield tests with replications after seed increase.

     

Assessment of genetic diversity among Chinese high-oleic peanut genotypes using miniature inverted-repeat transposable element markers

Genetic Resources and Crop Evolution - As compared with normal-oleic peanuts, high-oleic peanuts proved to be heart-healthier and had a prolonged shelf life and extended seed longevity. However,...     

Effect of location on starch content and tuber texture characteristics in potato breeding lines and cultivars

The texture of boiled potato tubers is one of the most important quality traits. The variation of tuber texture is usually examined in relationship with dry matter or starch content. The objective of the work was to examine variation and stability of texture and starch content in tubers grown in various environments. Both traits were evaluated for the set of potato breeding lines and 10 table potato cultivars. The lines were developed in the program of parental lines carried out in M?ochów Research Center, Poland. The environments were represented by three locations, which differed in cultivation system as well as climatic and soil conditions. The traits were influenced by the effects of genotype, location and their interactions. The effect of location on texture was not explained by the changes in starch content. The calculated stability parameters indicated that unstable expression of both traits was more pronounced and more frequent in breeding lines than in the cultivars. The short period of selection used in the development of the parental lines is not conducive to select potato genotypes with stable expression of quality traits. The starch content was at most moderately related with various characteristics of tuber texture.     

Relationships of sweet, bitter, and roasted peanut sensory attributes with carbohydrate components in peanuts

Certain roasted peanut quality sensory attributes have been shown to be heritable. Currently the only means of measuring these traits is the use of a trained sensory panel. This is a costly and time-consuming process. It is desirable, from a cost, time, and sample size perspective, to find other methodologies for estimating these traits. Because sweetness is the most heritable trait and it has a significant positive relationship to the roasted peanut trait, the possible relationships between heritable sensory traits and 18 carbohydrate components (inositol, glucose, fructose, sucrose, raffinose, stachyose, and 12 unknown peaks) in raw peanuts from 52 genotypes have been investigated. Previously reported correlations among sweet, bitter, and roasted peanut attributes were evident in this study as well. Where there was positive correlation of total sugars with sweetness, there also was positive correlation of total sugars with roasted peanut attribute and negative correlation of total sugars with bitterness and astringency. The expected generalized relationship of total sugars or sucrose to sweetness could not be established because the relationship was not the same across all market-types. Further work is needed to determine the nature of the chemical components related to the bitter principle, which appear to modify the sweet response and interfere with the sensory perception of sweetness, particularly in the Virginia market-type. Also, certain carbohydrate components showed significant relationships with sensory attributes in one market-type and not another. These differential associations demonstrate the complexity of the interrelationships among sweet, bitter, and roasted peanut sensory attributes. Within two market-types it is possible to improve the efficiency of selection for sweetness and roasted peanut quality by assaying for total carbohydrates. On the basis of the regression values the greatest efficiency would occur in the fastigiate market-type and then the runner.     

Oil, sugar, and starch characteristics in peanut breeding lines selected for low and high oil content and their combining ability

Peanut seeds contain approximately 50% oil on a dry weight basis, making them a high fat food. Reduction of the oil content would make peanuts a more desirable food to fat conscious consumers. Removal of existing oil by processing is not feasible for in-shell peanuts, the dominant product of the North Carolina-Virginia area. To reduce oil content in in-shell peanuts, a genetic solution must be found. However, while reduced oil content is a desirable objective, changes in oil must not be accompanied by significant decreases in any of the desirable aspects of peanut flavor. Because the impact of selection for low or high oil on flavor is not known, it would be useful to know in what form dry matter is being stored in the seed, particularly if it is not being stored as oil. Screening of 584 accessions identified two lines (PI 269723 and PI 315608) with high and two (Robusto 2 and Robusto 3) with low oil contents, each pair differing in sugar content. The four parents were crossed in diallel fashion to investigate patterns of inheritance. General combining abilities (GCA) for oil content closely followed values of the parental lines. One low oil parent (Robusto 2) had a correspondingly elevated GCA for sugar content, but neither low oil parent had the effect of elevating starch in progeny. Reciprocal cross differences were found for starch and sugar contents, suggesting influences of cytoplasmic genes on those traits. These lines serve as resource material for researchers interested in the genetic and physiological aspects of the oil-sugar-starch relationship in peanuts.     

鸡油组织中的磷脂对鸡油挥发性风味化合物形成的影响

磷脂是肉类特征性风味的重要前体物质。鸡油具有浓郁的脂香和鸡汤香气,磷脂可能对其风味有重要作用。该研究采用去除鸡油组织中的磷脂,以及在鸡油中添加磷脂等处理方法,结合顶空固相微萃取-气相色谱-质谱联用技术和感官评价方法研究经不同处理鸡油中的挥发性风味物质相对含量和风味的变化。结果表明添加了磷脂的鸡油,其特征性风味成分显著增加,特别是（E,E）-2,4-癸二烯醛和1-辛烯-3-酮分别增加了4.5倍和10.4倍;而去除磷脂鸡油的挥发性风味物质种类和丰度显著减少;感官评价结果也表明添加磷脂鸡油的风味最浓郁,而去除磷脂鸡油的风味最弱。因此,该研究证明鸡油组织中的磷脂对鸡油的风味具有重要的贡献作用,添加磷脂可显著增加鸡油的香气。该研究结果为浓香鸡油的开发提供理论依据和参考工艺。     

花生品质对其蛋白质凝胶性的影响

为了探讨不同花生品种的感官品质、理化与营养品质、加工品质与其蛋白质凝胶性之间的关系,提出适宜肉制品加工凝胶型蛋白质专用花生品种的主要特性和评价方法,构建适宜加工凝胶型蛋白质花生品质评价模型。以62个花生品种制得的分离蛋白粉为原料,采用物性仪测定其分离蛋白凝胶性,分析各品种花生的品质特性与凝胶性之间的关系,采用有监督主成分分析对41个品种的品质数据建立凝胶型蛋白质花生品质评价模型,并用另外21个品种品质数据进行验证。结果显示,不同品种花生蛋白质在相同条件下制得的凝胶特性差异显著。果形、粗蛋白、粗纤维、半胱氨酸、甘氨酸、精氨酸、亮氨酸、伴花生球蛋白Ⅰ、花生球蛋白/伴花生球蛋白、23.5kDa等10个指标与凝胶性在0.05水平上关系显著,采用有监督主成分分析建立凝胶型蛋白质花生品质评价模型,验证模型的相关系数为0.937。研究结果表明,花生的品质特性显著影响花生蛋白质的凝胶性。花生粗蛋白含量、胱氨酸含量、精氨酸及伴花生球蛋白Ⅰ含量高的品种具有更好的凝胶性。通过凝胶型蛋白质花生品质评价模型可以预测该品种花生蛋白质的凝胶性,为不同花生品种的加工利用和专用品种的选择提供依据。     

超高压微射流对花生蛋白结构的影响

为了探讨超高压微射流对花生蛋白理化性质和结构的影响.该文研究了花生蛋白溶液经超高压微射流处理后的颗粒大小、游离巯墓基团、疏水基团和紫外吸收基团的变化规律.结果表明:花生蛋白的颗粒尺寸和游离巯基基团含量随着超高压微射流均质压力的增大而显著减小;疏水基团和紫外吸收基团的含量则随着均质压力的增大而显著增大,说明超高压微射流处理可破坏花生蛋白的内部基团,使蛋白的结构发生变化.     

Effect of beta-cyclodextrin on aroma release and flavor perception

Binding and release of volatile compounds to and from beta-cyclodextrin were measured in model aqueous systems using static equilibrium headspace and dynamic headspace dilution. Beta-cyclodextrin decreased the static equilibrium headspace for some volatiles (e.g., ethyl octanoate and decanone) due to binding, but dilution studies demonstrated that binding was readily reversible. Dynamic release of hydrophobic volatile compounds was similar to that observed from emulsions. When beta-cyclodextrin was added to fat free yogurt, the release of a commercial lemon flavoring was modified and was similar to release from a regular fat yogurt. Sensory difference testing confirmed the release results. The data demonstrate that beta-cyclodextrin can be used to modify flavor delivery in both model and real systems; the effects in the latter are sensorially significant.     

利用缺体回交法选育小黑麦异代换系的研究

以4D缺体为母本，黑麦为父本进行杂交，授粉后16～18d进行幼胚培养，培养的试管苗用0．05%秋水仙素处理，加倍后的植株再用缺体回交1～2次，就可获得小黑麦异代换系。在第二次回交的F₁(B₁F₁)代里，单体代换植株占18．5%；双单体代换占24%，这两种类型经自交后都获得了4D／4R异代换系，有的异代换系已直接用于生产。     

超高压微射流对花生蛋白结构的影响（简报）

为了探讨超高压微射流对花生蛋白理化性质和结构的影响,该文研究了花生蛋白溶液经超高压微射流处理后的颗粒大小、游离巯基基团、疏水基团和紫外吸收基团的变化规律。结果表明：花生蛋白的颗粒尺寸和游离巯基基团含量随着超高压微射流均质压力的增大而显著减小;疏水基团和紫外吸收基团的含量则随着均质压力的增大而显著增大,说明超高压微射流处理可破坏花生蛋白的内部基团,使蛋白的结构发生变化。     

Effect of sucrose on the perceived flavor intensity of chewing gum.

The release of sucrose and menthone from chewing gum was measured in-mouth and in-nose, respectively, during eating. Swabs of saliva were taken from the tongue and analyzed using a rapid, direct liquid-mass spectrometry procedure. Menthone concentration in-nose was monitored on a breath-by-breath basis using direct gas phase atmospheric pressure chemical ionization-mass spectrometry. Simultaneously with the volatile release, trained panelists followed the change in mint flavor by time-intensity (TI) analysis. Two types of commercial chewing gum were analyzed. Both showed that the panelists perception of mint flavor followed sucrose release rather than menthone release. The temporal analysis of the chemical stimuli, with simultaneous TI analysis, provided unequivocal evidence of the perceptual interaction between nonvolatile and volatile flavor compounds from chewing gum.     

Effect of irrigation on soil aeration in relation to peanut production

The root zone of the plant must be well supplied with both water and oxygen. Water potential should be kept close to saturation but if a low water tension is maintained, particularly in clay soil, plants will suffer most of the time from a sub-optimal level of oxygen supply in the root zone. The diffusion rate of gases in air is about 10,000 times greater than in water. Thus, it is obvious that the rate of gas diffusion decreases as the water content of the soil increases. These two requirements are apparently contradictory and the assessment of optimum level of soil aeration in the root environment is essential for better crop establishment and growth. Influence of irrigation treatments (three depths of irrigation of 2, 4 and 6 r cm and four IW/CPE ratios of 0.45, 0.60, 0.75 and 0.90) on the soil oxygen diffusion rate (ODR) during various growing phases of peanut crop ( Arachis hypogaea L.) were studied on a lateritic sandy loam soil (ultisols) for two consecutive seasons. The rate of ODR decreases as water content of the soil increases after irrigation and then increases gradually with the lapse of time. However, it starts decreasing with decrease in soil moisture after 96 h of irrigation.     

超高压处理对杏汁香气成分的影响

为了探讨超高压处理对杏汁香气成分的影响,将杏原汁在500 MPa压力、25℃温度条件下处理20 min后,经顶空固相微萃取与毛细管气相色谱-质谱联用技术检测超高压处理前后杏汁香气成分的变化,并用面积归-化法测定了各种成分的质量分数.结果表明超高压处理后对杏汁中香气成分的有较明显影响,其中己醛、2-己烯醛、糠醛、己醇、叶醇、芳樟醇、橙花醇、β-苯乙醇等香味成分的质量分数分别增长了68.14%、95.26%、46.76%、61.11%、58.56%、35.75%、37.75%和42.30%;酯类、内酯类的香气成分的含量有所降低;酮类香味成分的含量则没有明显变化.感官评定表明:超高压处理不仅能很好地保持了杏的特征香气,而且使杏汁的青鲜香气更加突出,有利于产品风味品质的提高,这与杏汁中香气成分检测结果相一致,因此对杏加工来说超高压处理是一种很有前景的冷加工技术.     

连作对花生根系分泌物化感作用的影响

采用连续收集法提取连作5 年、3 年和轮作处理的花生结荚期根系分泌物, 研究其对土壤微生物及花生种子发芽、幼苗生长发育和细胞膜过氧化的化感作用及连作对花生根系分泌物化感作用的影响。结果表明,花生结荚期根系分泌物对花生根腐镰刀菌36194 菌丝的生长、叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性及丙二醛(MDA)含量存在促进作用, 对固氮菌14046 的生长, 花生种子胚根的伸长、幼苗的苗高、茎叶鲜重、根系鲜重、叶片叶绿素含量等有抑制作用, 促进和抑制作用均随根系分泌物添加浓度和连作年限的增加呈增强趋势。连作花生结荚期根系分泌物化感物质在土壤中的累积, 很可能是导致花生连作障碍的原因之一。     

Effect of forest management on the breeding bird community in southern Sweden

A natural and a managed forest of similar age were compared. Total bird density was three times higher in the natural forest. All species groups had higher population densities in the natural forest, but woodpeckers and warblers much more so than other groups. Hole-nesting species made up about the same proportion of the bird communities in the natural and the managed forests.Bird density in a young spruce plantation was one-ninth of that in the natural forest. Species number was higher in the natural than in the managed forest.