Evaluation of peach and nectarine fruit quality and correlations between sensory and chemical attributes

Sensory attributes and chemical composition in peach and nectarine fruits of nine different cultivars were evaluated and compared. The cultivars investigated in the research were: ‘Maria Marta’, ‘Romestar’, ‘325 × A/8’, ‘224 × A/13’, ‘V × S/4’, ‘Bea’, ‘Maria Aurelia’, ‘Venus’ and ‘Spring Red’. In sensory evaluation the ‘Maria Aurelia’ was the highest rated, and the ‘224 × A/13’ was the lowest. The cultivars ‘325 × A/8’, ‘224 × A/13’, ‘V × S/4’ and ‘Spring Red’ were poor in sugars; however, the ‘Spring Red’ was rich in organic acids. Similarly, the ‘Maria Aurelia’ and ‘Venus’ fruits had higher contents of organic acids and were also rich in sugars. Furthermore, the relationships among sensory and chemical attributes of fruit quality were studied. The sensory evaluations of sweetness, taste, and aroma were well correlated with some chemically measured attributes of peach and nectarine quality: sweetness was influenced by citric acid, shikimic acid and sugars/organic acids ratio; aroma was correlated with total organic acids, sucrose, sorbitol and malic acid; taste was related to malic/citric acid ratio, total sugars, sucrose, sorbitol and malic acid. The results of the research indicate that sensory evaluation provides a good tool in the quick assessment of peach and nectarine fruit quality. Copyright © 2005 Society of Chemical Industry     

Sensory, chemical and gas chromatographic evaluation of five raspberry cultivars

Five raspberry cultivars, ‘Chilcotin’, ‘Chilliwack’, ‘Meeker’, ‘Skeena’ and ‘Tulameen’, were evaluated for sensory attributes, and chemical and flavor volatile compounds. ‘Chilliwack’ and ‘Tulameen’ received high ratings in sweetness and overall impression with high soluble solids, total sugars and sugar:acid ratio. ‘Chilcotin’ rated low in overall impression and sweetness, and high in sourness and astringency, with low soluble solids, sugar:acid ratio and total sugars, and high titratable acidity. Principal factor analysis (PFA) of the sensory results separated the cultivars based on desirable (appearance, color, texture, aroma and sweetness) and less desirable (sourness, bitterness, astringency and off-flavor) attributes. Twenty-eight volatile compounds were analyzed by dynamic headspace and 18 identified by gas chromatography-mass spectrometry (GC-MS), most of which were terpenes which included -pinene, sabinene, γ-terpinene, - and β-ionone and caryophyllene. Volatile compounds varied among cultivars, with benzaldehyde (11·1–31·8%), -pinene (4·0–11·5%), ethyl heptanoate (6·9–15·2%), β-myrcene (13·2–19·6%) and γ-terpinene (12·2–20·0%) as the predominant volatiles. Correlation analysis established no relationships between sensory and chemical data with volatile compounds.     

Analysis of phenotypic variation of sugar profile in different peach and nectarine [Prunus persica (L.) Batsch] breeding progenies

BACKGROUND: Specific sugar contents are well known for contributing to a range of quality traits of fresh fruits such as flavour, texture and health properties. Peaches and nectarines of 205 genotypes from 14 different breeding progenies cultivated under Mediterranean conditions were evaluated by high‐performance liquid chromatography for their content of these sugar traits. RESULTS: A high contribution of cross to the phenotypic variance of all evaluated fruit quality traits was found. There were significant differences in mean sugar concentrations between peach and nectarine, yellow‐ and white‐fleshed or freestone and clingstone genotypes. Pre‐selected genotypes from the original breeding programme showed enhanced soluble solid content (SSC), total sugar and sucrose contents. A significant effect of year was found for SSC, sucrose and glucose contents, whereas no effect was found for fructose and sorbitol contents. Individual sugar contents correlated significantly with each other and with other fruit quality traits. CONCLUSION: A significant effect of cross, year and qualitative traits on the sugar profile of peaches and nectarines was found. Moreover, the differences shown in sugar traits between the breeding population and the pre‐selected genotypes indicated the importance of sugar profile in the global quality of peaches and nectarines. Copyright © 2009 Society of Chemical Industry     

Quality, bioactive compounds, and antioxidant activity of new flat-type peach and nectarine cultivars: a comparative study

In this work, some organoleptic and nutritive parameters related to fruit quality (color, firmness, total soluble solids, and total acidity), the content of bioactive compounds (total phenolics and total carotenoids) as well as the total antioxidant activity (TAA) due to hydrophilic (H-TAA) and lipophilic (L-TAA) compounds have been determined in both skin and flesh of 10 flat peach and nectarine genotypes (7 peaches and 3 nectarines). Results showed that genotype plays an important role in determining the organoleptic and nutritive quality, as well as the concentration of bioactive compounds and the related TAA, since these parameters differed largely among cultivars. Overall data suggest that for commercial purposes and consumer's acceptability (based on color, firmness, acidity, and bioactive compounds), the flat nectarine "ASF-06-83" and the flat peaches "Sweet Cap" and "ASF-06-91" could be considered as the best cultivars. Additionally, it is suggested that the content of bioactive compounds should be included as an important factor in future breeding program to obtain new genotypes with enhanced bioactive compounds. PRACTICAL APPLICATION: Genotype of flat peaches and nectarines plays an important role in determining the organoleptic and nutritive quality, as well as the content of bioactive compounds. Given the differences on bioactive compounds concentration and antioxidant activity among peaches and nectarines flat cultivars, these parameters should be included as an important factor in future breeding program to obtain new genotypes with enhanced bioactive compounds.     

基于游离氨基酸、挥发性组分和感官评价的2 种酸化技术加工乳饼的滋味特征差异分析

为明确传统酸水乳饼和发酵型乳饼的特征呈味物质,利用氨基酸分析仪和气相色谱仪分别对传统酸水乳饼和发酵型乳饼中的特征呈味物质（游离氨基酸、游离脂肪酸）进行测定,采用滋味活度值（taste activity value,TAV）判定特征呈味物质,同时进行感官评价;并且结合游离氨基酸和挥发性成分分析特征呈味物质与感官属性之间的相关性。结果表明,谷氨酸、组氨酸和癸酸、月桂酸、肉豆蔻酸、油酸、亚油酸的TAV大于1,对乳饼的滋味有着重要贡献。在感官和呈味物质组成方面,2 种工艺加工的乳饼明显区分开。发酵型乳饼的总体滋味强度高于传统酸水乳饼（P＜0.05）,感官属性以酸味、甜味、苦味和鲜味为主,而传统酸水乳饼伴有不愉悦的异味。偏最小二乘法对特征呈味物质与感官属性之间的相关性分析表明,感官属性与游离氨基酸相关性高,传统酸水乳饼的咸味与精氨酸,异味与甘氨酸、癸酸和棕榈烯酸呈显著正相关（P＜0.05）;发酵型乳饼的酸味与硬脂酸和亚油酸,甜味与天冬氨酸、苏氨酸、丝氨酸、谷氨酸、丙氨酸以及亚油酸,苦味与缬氨酸、蛋氨酸、异亮氨酸、亮氨酸、酪氨酸以及肉豆蔻酸,鲜味与天冬氨酸、谷氨酸、丙氨酸均呈显著正相关（P＜0.05）。发酵酸化技术促进蛋白质和脂肪的分解,改善乳饼的滋味。     

Chemical compounds and sensory assessment of kiwifruit (Actinidia chinensis (Planch.) var. chinensis): electrochemical and multivariate analyses

This study reports the analytical and sensory analyses made on selected kiwifruit genotypes (Actinidia chinensis (Planch.) var. chinensis) produced from seeds of fruit gathered in the Guangxi region of the People’s Republic of China. The analytical measurements of some soluble sugars, such as glucose and fructose, and non-volatile acids, such as malic and ascorbic acid, were carried out using innovative analytical procedures based on fast and selective devices that require very little or no sample treatment. The multivariate techniques, Principal Component Analysis and Cluster Analysis, useful when many variables are involved, allowed the classification of kiwifruit genotypes according to sugar and non-volatile acid contents and sensory properties. Citric acid, the major organic acid, ranged from 0.8 to 1.8 g per 100 g of fresh weight and malic acid content was 0.1–0.5 g per 100 g of fresh weight. The levels of fructose and glucose (present in approximately equal amounts in most of the genotypes analysed), were higher than that of sucrose in almost all the genotypes. Ascorbic acid content in kiwifruit samples from genotypes of Actinidia chinensis (Planch.) var. chinensis was higher than the typical mean content in Actinidia chinensis var. deliciosa (A Chev) cv Hayward. Sensory assessment showed that total fruit aroma and flavour were the best discriminating attributes and were highly correlated with overall quality. No consistent correlation was found between overall quality and the sensory attributes of sweetness, juiciness and firmness.     

Sensory quality and compositional characteristics of blackcurrant juices produced by different processes

Effects of enzymatic and non-enzymatic juice pressing on key orosensory and chemical quality factors of blackcurrant juices were studied in laboratory scale using berries of five different cultivars (Mortti, Mikael, Marski, Ola and Breed15). Enzymatic processing increased the juice yield by 10–22% and the content of various phenolic compounds in juice by 4–10-fold as compared to the non-enzymatic process. Higher intensity of the mouth-drying astringency of the enzyme-aided juice was the most significant orosensory difference between the processes. Juices of different blackcurrant cultivars varied in sweetness, sourness and bitterness. The most intensive sensory attributes of the juices were sourness and puckering astringency regardless of processing method. They correlated positively with each other and were contributed by acid content and pH. In enzyme-aided juices, the contents of flavonol glycosides and hydroxycinnamic acids were associated with mouth-drying astringency, and sugar/acid ratio correlated with sweetness. These correlations were less clear in non-enzyme juices possibly due to lower content of phenolic compounds and the high content of pectin.     

Preliminary characterisation of peach cultivars for their antioxidant capacity

Eleven peach cultivars (white‐ and yellow‐flesh peaches, nectarines and canning clingstone peaches) were assayed for their antioxidant capacity and their content of some important organic compounds as well as vitamin C, carotenoids and phenols. Antioxidant capacity, determined by FRAP assay, varied between genotypes. Those with the highest value of Ferric Reducing Antioxidant Power (FRAP) were Federica and Springcrest. Antioxidant capacity was correlated to the amount of organic components with significant differences among the cultivars. In some case, antioxidant capacity was related to phenol content, as in yellow–flesh peaches. These results suggest the importance of genotype for determining antioxidant capacity, which, in turn, is related to the organic constituents, such as phenols, vitamin C and carotenoids.     

Radiation Disinfestation of California Stone Fruits Infested by Medfly—Effectiveness and Fruit Quality

The effectiveness of radiation disinfestation of California peaches, nectarines and plums infested by Mediterranean fruit flies (Ceratitis capitata) and the effects of gamma-radiation up to 1 kGy (100 krad) on the sensory qualities of these fruits were studied. Medfly eggs in infested peaches and nectarines treated at 0.4–0.5 kGy (40–50 krad) in a Cobalt-60 irradiator did not hatch. Results in irradiated plums were inconclusive. Results of triangle tests with a taste panel of 15–20 show no differences in sensory qualities between plum and nectarine samples irradiated at 0.3 kGy and their controls. Some differences were detected between irradiated samples and controls: color and flavor of peaches at 0.3 kGy; color of plums and peaches 0.5 kGy; aroma of peaches and texture of plums at 0.5 kGy. At 1 kGy, differences were found in the texture of plums, nectarines, and peaches, and color and flavor of nectarines. Better control of harvesting, shipping and handling would help retain the qualities of these irradiated fruits.     

Assignation of Sweet Cherry Selections to 3 Taste Groupings Based on Perceived Sweetness and Sourness

ABSTRACT: Providing consumers with basic taste properties of sweet cherries at point of purchase would allow consumers to make purchase decisions based on fruit's intrinsic sensory attributes. The objective of this study was to develop a model to predict taste-grouping assignation of cherries into the following categories: (1) low sweetness/high sourness, (2) balance between sweetness and sourness, and (3) high sweetness/low sourness. A sensory panel (n = 10) was trained to recognize sweetness and sourness in 5 cultivars of sweet cherries and assign a taste grouping based on the perceived balance of sweetness and sourness. Four of these same cultivars were then evaluated for sweetness and sourness by a consumer panel (n = 117) and instrumentally for titratable acidity (TA) and soluble solids concentration (SSC). Results showed that for 3 of the 4 cherry cultivars, the sweetness/sourness balance of the cherries was not significantly different as evaluated instrumentally or by the trained panel. However, the balance determined by the consumer and the trained panel was different for 3 of the 4 cherry cultivars (P < 0.05). Based on trained panel perceived sweetness and sourness, a multinomial logit model was developed to predict the assignation of cherry taste grouping. The likelihood of group assignment depended on both the perceived sweetness and sourness of the cherry, with taste groupings agreed upon for 3 of 5 sweet cherry cultivars. As previous studies have indicated a positive relationship between cherry sweetness and sourness to consumer acceptance, these groupings show promise for assisting consumers in cherry selection at the point of purchase. Practical Applications: The prediction models proposed in this study suggest that both sweetness and sourness are important in the cherry characterization and the ratio between the 2 attributes may be appropriate for making taste-grouping assignments. These groupings may then be used to provide additional sensory information to consumers to assist them in cherry selection at the point of purchase.     

CHANGES OF SUGAR PROFILES IN CANNED CLINGSTONE PEACHES

The effect of post-canning storage on sugar profiles in canned clingstone peaches (Primus persica var. ‘Halford’) sweetened with various combinations of sucrose, 62 D. E. corn syrup and 42% high fructose corn syrup was investigated. The sugars in the peach syrups were monitored at 1, 20 and 30° C after storage for 0, 6, 9 and 12 months. The individual sugars in the peach syrups were separated and analyzed by high pressure liquid chromatography (HPLC). Storage of the canned peaches at 30° C resulted in a rapid decrease in sucrose and a simultaneous increase in fructose and glucose. The hydrolysis of sucrose was successively slower at 20 and 1°C. It was observed that the sugar profiles were also dependent on the initial concentration of the sugar components, time of storage and acidity of the canned peaches. The concentration of maltose showed great fluctuation during storage. The rapid loss in quality acceptance of canned clingstone peaches at high storage temperature was explained by the changes in sugar profiles and the accompanying undesirable chemical and physical changes.     

Variations in the soluble sugar and organic acid contents in radish (Raphanus sativus L.) cultivars

The radish is a root vegetable of the Brassicaceae family that is mainly consumed in Far Eastern Asian countries. Because chemical indexes indicating the quality of a radish have not been established, we investigated the variations in the contents of the soluble sugars and organic acids that influence taste among seven radish cultivars. In terms of the total soluble sugar content, which is a strong index of sweetness, Koshin, Kouto, and Shogoin were the three highest among the seven cultivars. Sobutori, which is the most common radish cultivar in Japan, was the lowest. The total organic acid contents varied among the seven cultivars, although they were five to thirteen times lower than the total soluble sugar contents. These results indicate that there are variations in the soluble sugar and organic acid contents among radish cultivars; therefore, these contents may be used as chemical indexes for the quality of radishes.     

不同肉质桃品种的2 个成熟度果实常温贮藏特性比较

目的：比较不同肉质和成熟度的桃品种常温条件下的贮藏特性。方法：以软溶质型桃‘霞晖1号’、硬溶质型桃‘霞晖6号’、不溶质型桃‘金晖’为试材,研究7、8 成熟度条件下果实常温贮藏过程中果实硬度、乙烯释放量、可溶性固形物、可溶性糖和有机酸含量的变化。结果：货架期间,所有处理桃果实均有正常乙烯释放峰值出现,不溶质桃果实具有最长的果实货架生理周期,但可溶性固形物和可溶性糖含量较软溶质和硬溶质品种低,风味不足,‘霞晖6号’8 成熟果实在贮藏过程中,能保持较高的可溶性固形物和可溶性糖含量,风味渐佳。结论：硬溶质肉质类型桃在货架期间贮藏效果较好,8 成熟是其适宜的采收成熟度。     

Multivariate analysis of maturity stages,including quality and aroma,in ‘Royal Glory’ peaches and ‘Big Top’ nectarines

Ethylene production, quality attributes and aroma compounds were analysed to determine the maturity evolution of ‘Big Top’ nectarines and ‘Royal Glory’ peaches at harvest dates ranging from 89 to 116 days after full bloom (DAFB) for nectarines and from 85 to 112 DAFB for peaches. These cultivars are highly coloured even in the early stages of maturity. However, the two cultivars had different patterns of ethylene production, this being slower in nectarines than in peaches. Principal component analysis (PCA) was used to provide partial visualisation of the complete data set in a reduced dimension plot. Separation of the two cultivars can be shown by means of a two‐dimensional plot of the samples. Although only some aroma compounds are slightly correlated with quality parameters, when aroma volatiles were included in the PCA, the aroma compound set allowed both cultivars to be classified into three stages of maturity: immature, intermediate and fully mature. Compounds such as propanol, hexyl acetate, 2‐methylpropyl acetate, limonene, butanol, (Z)‐3‐hexenyl acetate, buthyl acetate, linalool, ethanol, propyl acetate and ethyl acetate are the most important volatiles for ‘Big Top’ nectarines. It is suggested that the presence of these compounds can be used to indicate when the fruit should be harvested. The presence of γ‐decalactone, δ‐octalactone, γ‐octalactone, ethyl butyrate, hexanal and (E)‐2‐hexenol can be used to indicate the harvesting maturity stage for ‘Royal Glory’ peaches. The optimum maturity date for harvest would be 105–107 DAFB for ‘Big Top’ nectarines and 93–95 DAFB for ‘Royal Glory’ peaches. © 2002 Society of Chemical Industry     

乳酸菌发酵桃脯制备工艺

以桃为原料进行乳酸菌发酵,然后利用发酵后的桃块经糖液煮制,常温浸糖,适温烘制做成乳酸菌发酵桃脯。通过试验,确定乳酸菌发酵桃脯制备方法:45%糖液煮至桃没有生心,糖煮时间10 min,常温浸糖时间24h,将浸糖后成型的桃块放入烘箱中,60℃烘制20 h。按照此方法制得的桃脯酸甜可口,不仅桃味浓郁,而且还具有乳酸菌发酵产品特有的风味。     

Sensory Attributes and Instrumental Analysis Relationships for Strained Processed Carrot Flavor

Regression models relating sensory attributes and composition of tin genotypes of processed strained carrots were developed. Fresh carrot-flavor, aroma, and aftertaste were associated with high total sugar to terpinolene ratios. Sweet taste and sweet aftertaste were associated with high levels of total sugar and high total sugar to terpinolene ratios. Cooked flavor and cooked aftertaste were associated with high terpinolene content. Selection of genotypes with high total sugar to terpinolene ratios should improve strained processed carrot sensory quality.