Cultivar discrimination of stored apple seeds based on geometric features determined using image analysis

Digital image analysis can allow determining the features of seeds and their interpretation in a fast, inexpensive, and non-destructive way. The research aimed to develop discriminative models based on geometric features to distinguish seeds belonging to different apple cultivars. Images of seeds of apples ‘Gala’, ‘Jonagold’ and ‘Idared’ were acquired using a flatbed scanner. The linear dimensions and shape factors were calculated, and after attribute selection, they were used for the discriminant analyzes of seeds for ‘Gala’ with ‘Idared’, ‘Gala’ with ‘Jonagold’, ‘Idared’ with ‘Jonagold’ and ‘Gala’ with ‘Idared’ with ‘Jonagold’ with the use of discriminative classifiers from Bayes, Function, Meta, Rules and Decision Trees groups. In the case of models build based on selected linear dimensions, the accuracy of discrimination was equal up to 84% for distinguishing seeds of all three apple cultivars for the J48 classifier from Decision Trees and 93% for analysis of ‘Gala’ and ‘Idared’ for the J48 from Decision Trees. The slightly lower correctness of up to 82% for discrimination of ‘Gala’, ‘Idared’ and ‘Jonagold’, Multi Class Classifier) and 90% (‘Gala’ and ‘Jonagold’, J48) were obtained for models build based on selected shape factors. The analyzes performed based on sets including selected combined linear dimensions and shape factors of seeds provided the correctness of up to 86% for the discrimination of three apple seed cultivars (J48) and 91% (‘Gala’ and ‘Jonagold’, J48). The results can be used in practice for the assessment of the authentication of seeds of apple cultivars with high probability.     

Antioxidant enzyme activities in apple varieties and resistance to superficial scald development

The activities and isozyme profiles of superoxide dismutase (SOD), guaiacol peroxidase (POX) and ascorbate peroxidase (APX) were monitored in skin tissues of scald-resistant and scald-susceptible apple cultivars (Malus domestica Borkh.). SOD activity was high in Gala, with moderately high levels in Idared, McIntosh and Delicious, and low levels in Cortland and Empire. Guaiacol peroxidase activities were high in Empire, McIntosh and Delicious, with moderate to low levels in Cortland, Gala and Idared. Ascorbate peroxidase activity was nearly similar in all the cultivars. Native PAGE and activity staining showed great differences in the guaiacol peroxidase isozyme profiles. Ascorbate peroxidase isozyme profiles showed a fast moving isozyme present in all cultivars. Tissue printing for peroxidase in varieties such as Empire and Crispin showed intense activity, especially in the epidermal region. α-Farnesene levels were variable in all the cultivars. The results suggest that other biochemical characteristics in addition to the antioxidant enzyme activities and α-farnesene levels may be involved in determining the susceptibility/resistance to superficial scald development.     

Allergenicity of different apple cultivars assessed by means of skin prick test and sensitisation to recombinant allergens Mal d 1 and Mal d 3 in a group of Italian apple‐allergic patients

To evaluate differences in skin prick test response to apple cultivars in patients with apple allergy, 19 patients (10 adults and 9 children) underwent prick‐to‐prick skin prick test with eleven commercial and noncommercial apple cultivars, and evaluation of specific IgE to apple and recombinant apple allergens Mal d 1 and Mal d 3. The results show that different reactions might be evoked in a single patient by different apple cultivars and also separately for the peel and the pulp of a single cultivar. The cultivars were ranked according to their allergenicity level, being Jonathan, Jonagold, Golden Delicious and Fiesta the most allergenic when considering the pulp and Gala, Fiesta and Golden Delicious for the peel. Further investigations are needed to clarify if a single patient can be allergic only to well‐defined apple cultivars and which allergometric tests are necessary to ascertain this.     

Effects of various clarification treatments on phenolic compounds and color of apple juice

The purpose of this study was to investigate the changes that occur during conventional clarification using gelatin, bentonite, silica sol, and water-soluble chitosan on the phenolic compounds, antioxidant activity, and color of apple juice. The apple material used in this study was of two varieties: Sampion and Idared. The changes in the polyphenols composition (procyanidins, hydroxycinnamic derivatives, and dihydrochalcones) were monitored through the clarification process. Sampion apple control juices contained more total polyphenols than do Idared apple juices. In Sampion variety apple juice, the dominant polyphenols are the flavan-3-ols (86% of total polyphenols), followed by hydroxycinnamic acids (9.7%), dihydrochalcones (3.0%), and flavonols (1.3%). In Idared apple juice the hydroxycinnamic acids (especially chlorogenic acid) are dominant (about 48% of total polyphenols), followed by flavan-3-ols (40%). However, the concentration of polymeric procyanidins in Sampion apple juices was 62.8 and 46.3% less when the Profloc (chitosan) and gelatin treatments were used, respectively. Aktivbentonit and Puranit (bentonite) supplementary added in juices clarification have some protective effect on polymeric procyanidins only with Profloc treatment. That kind of effect was not observed in Idared apple juices with almost eight times smaller polymeric procyanidins concentration than in Sampion apple juices. The antioxidant activity, measured by the DPPH (1,1-diphenyl-2-picrylhydrazyl radical) method, ranged from 0.20 mg TEAC/mL in Idared apple juice to 0.30 mg TEAC/mL in Sampion apple juice, measured by the ABTS method, from 0.17 to 0.48 mg TEAC/mL, respectively. Clarification of apple juices with chosen clarifying agents has statistically no significant (p>0.05) influence on antioxidant capacity. This study suggests that chitosan can be used as a conventional clarifying aid of apple juices and that treatment has no impact on their biochemical parameters.     

DEVELOPMENT OF A PHOTOGRAPHIC SCALE FOR THE VISUAL EVALUATION OF APPLE STRIPE DENSITY1

This research developed a photographic scale for the evaluation of stripe density for 5 apple cultivars (Carousel, 8M-15-10, Fuji, Gala, and Jonagold) using a series of two experiments. In Experiment 1, subjects were able to significantly discriminate and reproducibly score the stripe density of apples using unstructured graphic line scales. Photographs of selected apples were then labelled with the corresponding mean scores and used as visual references for Experiment 2. In Experiment 2, subjects reproducibly evaluated the stripe density of apples using structured line scales (anchored with 3 or 5 photographic references), with similar mean scores from the 3- or 5-point scales. Subject differed very little in their variances reflecting the potential usefulness of these line scales for commercial evaluation of apple stripe density in whole apples.     

Differentiation of volatile aroma components in organically and conventionally produced apples by stir bar sorptive extraction combined with gas chromatography and EI/CI TOF mass spectrometry

Volatile aroma components and contents of organically and conventionally produced apples of the cultivars Elstar, Jonagold, Jonagored and Braeburn were studied. In three cultivars investigated, the aroma contents of organically produced apples were significantly lower (Elstar 16%, Jonagold 29%, Jonagored 68%). For Braeburn, no statistically significant difference was observed. In particular, the main aroma components were present at much lower concentrations in organically produced apples. In all apple cultivars, these were hexanal, trans-2-hexenal, 2-methylbutylacetate and hexylacetate. twenty-three aroma components were identified in total, in different relative ratios in the different apple cultivars: saturated esters, saturated and unsaturated aldehydes and alcohols. Some components identified in the conventionally produced cultivars were not present in the organically produced cultivars at all. The aroma components were extracted from juice freshly prepared from the apples by stir bar sorptive extraction (SBSE) technique and characterised by FID gas chromatography and EI/CI TOF mass spectrometry.     

纳米SiOx保鲜果蜡对苹果贮藏性能的影响

以"乔纳金"和"红富士"为试材,研究了纳米SiOx保鲜果 蜡对两个品种苹果果实的呼吸强度、失重率、硬度和可溶 性固形物含量变化的影响。实验结果表明,纳米SiOx保 鲜果蜡有效抑制了果实的呼吸强度,显著降低了果实的 失重率,延缓了果实硬度和可溶性固形物含量的下降(p< 0.05),其对苹果货架期的延长已经与进口果蜡相近,某些 性能甚至优于进口果蜡。     

Changes of contents and antioxidant activities of polyphenols during fruit development of four apple cultivars

Polyphenols are functional components in apples and can be separated into four groups by Sephadex LH-20 as epicatechin, procyanidolic oligomers, chlorogenic acid and procyanidolic polymers. Antioxidant activities of each group were determined by FRAP and DPPH radical scavenging assay. It was found that procyanidolic oligomers and procyanidolic polymers influenced the total polyphenols content (measured by Folin–Ciocalteu method) much more in Jonagold, Golden Delicious, Fuji and Guoguang four apple cultivars. The Fe-reducing activity of procyanidolic oligomers in the four apple cultivars increased significantly during the development while the other three compounds changed irregularly. And the Fe-reducing activities of epicatechin and procyanidin contributed much more to the total Fe-reducing activities during the fruit development in the four apple cultivars. The DPPH scavenging activities of four compounds in Jonagold and Golden Delicious decreased during fruit development and that of Fuji and Guoguang changed irregularly. Chlorogenic acid was the main contributor in Jonagold, Golden Delicious and Fuji to the total scavenging activity. In Guoguang, it was procyanidolic oligomers that contributed much to the total scavenging activity.     

Synthesis of higher alcohols during cider processing

Ciders from two apple cultivars Gloster and Gala, were prepared. Apples were crushed and juice was extracted, immediately after crushing or after 24 h of maceration. Juice was allowed to ferment at 15°C and analysed for higher alcohols and sugars during fermentation. All higher alcohols analysed increased during fermentation as a result of yeast activity. More higher alcohols were synthesised in cider made from Gala cultivar than in cider from Gloster cultivar. Maceration increased the synthesis of iso-amyl alcohol, 2-phenyl ethanol, n-propanol, n-butanol, iso-butanol and methanol. Sensory evaluation classified cider made from non-macerated Gloster cultivar as the best followed by non-macerated Gala cultivar and macerated Gala cultivar. Sensory evaluation score correlated negatively to the sum of higher alcohols.     

Comparative polyphenolic antioxidant profile and quality of traditional apple cultivars as affected by cold storage

‘Kathista’ and ‘Lortiko’ are regarded as traditional and highly appreciated apple cultivars in Cyprus, yet their postharvest behaviour and phytochemical content are largely unknown. Such fruits were examined for their qualitative traits, phenolic composition and antioxidant capacity after harvest or short, intermediate or extended cold storage and additional ripening at room temperature (RT), using ‘Gala’ as reference cultivar. Total phenolic content was dependent on cultivar and length of cold storage, while hydroxycinnamic acids were always at higher levels compared to total flavonols for all the examined cultivars. No clear trends regarding the influence of cold storage or RT maintenance on fruit antioxidant properties were evident. Overall, quality attributes and polyphenolic content of the traditional apple cultivars were comparable with ‘Gala’ at harvest; thus, they can be considered a good source of nutraceuticals as summer apple cultivars. However, extended cold storage deteriorates fruit behaviour and antioxidant capacity, particularly in ‘Lortiko’ fruit.     

基于品质指标的苹果浊汁品种与产地差异性分析

以来自7?个不同主产区的21?个主栽品种,共41?份苹果鲜果为研究对象,对每个品种鲜榨浊汁的出汁率、浊度、果汁颜色、褐变度、透光率、可溶性固形物、可滴定酸、总酚、糖、有机酸、VC、矿物质、抗氧化性等品质指标进行测定。运用描述性分析、逐步线性判别分析进行数据处理。结果表明：不同品种或不同产地的苹果浊汁,品质差异较大。总体来看,a*值、原始浊度、褐变度、可滴定酸、葡萄糖、蔗糖、苹果酸等指标的变幅均较大,分别为94.07%、70.41%、42.86%、35.26%、42.02%、42.40%、37.69%。对于不同品种的苹果浊汁,由于褐变度、总酚、抗氧化性等色泽品质指标以及糖、酸等营养品质指标间具有较大差异,其分布呈现分散状态。其中新红星品种的褐变度、总酚含量、DPPH自由基清除率等品质指标普遍居高,色泽品质差异最显著。富士品种大部分样品的果糖、葡萄糖、蔗糖、苹果酸等指标含量较高,具有较好的营养品质。然而对于不同产地间的样品,其浊度、可滴定酸、可溶性固形物等加工品质指标具有较大差异,样品分布较为分散。河北省样品的出汁率、原始浊度、可滴定酸等指标普遍较低,加工品质较差。来自山东省不同品种苹果浊汁的样品以及来自不同产地富士苹果浊汁的样品间均具有较大差异,并且分别获得了77.8%和72.7%的判别准确率。以上结果表明,不同产地、不同品种苹果原料制得的苹果浊汁存在较大差异,通过对其品质指标进行差异性分析,可为上游育种与种植产业结构调整提供数据基础;通过判别模型的建立实现品种与产地的识别与预测,可以指导企业对苹果原料进行制汁专用化筛选。     

Polyphenol content and antioxidative activity in apple purées with rhubarb juice supplement

The purpose of the present study was to evaluate the effect of rhubarb juice addition and peeling in apple purée production and storage on its phenolic composition, antioxidant activity and colour. The apple material used in this study was of two varieties: Sampion and Idared. The apple purées prepared in three variants (control purées, peeling purées and purées with 5% of rhubarb juice) were stored for 3 and 6 months at 30 °C. Apple purées were investigated for their antioxidant activity, change of colour and contents of phenolic compounds plus the polymer procyanidins and degree of polymerization (DP). The preparation of purées from apples without peeling and the addition of rhubarb juice during purée preparation had significant influence on polyphenol content. The purée prepared from peeled apples of Idared variety had phenolic content 2.2 times lower than the control sample (non‐peeled apples). The highest level of total polyphenols was found in Idared + rhubarb sample (129.82 mg 100 g^?1 purée). The content of this compound in Idared control sample was more than 2.8 times lower than in Idared purées with rhubarb. The use of non‐peeled Idared apples and 5% of rhubarb juice in purée preparation significantly increased polymeric procyanidins from 11.68 to 75.20 mg 100 g^?1 and other phenolics from 9.23 to 54.62 mg/100 g. This effect for Sampion apples was smaller. The procyanidins during purées storage were more stable in samples with rhubarb juice addition. The purée samples with the addition of rhubarb juice had higher antioxidant activity measured using ABTS (2,2′azinobis‐(3‐ethylbenzthiazoline‐6‐sulphonic acid)) than purée samples without the addition (two times higher for Idared variety) of rhubarb juice. After 3 and 6 months of storage at temperature 30 °C, the antioxidant capacity decreased in all purées. Rhubarb juice had only high and positive effect on L* value in the case of Idared variety. The results showed that all Sampion apple purées had higher L* values than Idared.     

不同品种苹果化学成分及抗氧化活性比较

测定13种苹果的L-抗坏血酸、可溶性糖、滴定酸和总酚含量及pH值,比较13种苹果的抗氧化活性,包括还原力、脂质过氧化抑制率、 ·OH和DPPH自由基清除率,并依据化学成分对13种苹果进行聚类分析。结果表明,13种苹果的化学成分及抗氧化活性有差异,其中以新红星、藤牧1号和延光的抗氧化活性最强,而秦冠、粉红女士和红富士的抗氧化活性最小。苹果中的总酚含量与抗氧化活性之间显著正相关,两者均受基因型影响。聚类结果显示,美国八号、太平洋红玫瑰为抗坏血酸含量最高的一类,可溶性糖含量较高的乔纳金、太平洋红玫瑰、粉红女士、秦冠和红富士聚为一类,粉红女士为滴定酸含量最高的一类,糖酸比最高的一类是秦冠和红富士,藤牧1号、延光、新红星和乔纳金的总酚含量较高。     

基于图像处理的苦荞品种判别

为了建立不同品种苦荞种子的正确分类方法,以11个不同品种的苦荞种子为研究材料,使用扫描仪获取种子彩色图像,通过图像处理软件提取每个种子的特征变量28个,建立了一个包含11个品种440个苦荞种子,12 320个数据的矩阵。通过逐步法筛选有效特征变量,并利用有效变量构建判别模型。结果表明,筛选出的18个变量中,颜色变量为苦荞品种判别的主要变量。颜色变量和形态变量相结合,构建的贝叶斯判别模型,回判正确率达到了96.8%,交互验证正确率达到了94.7%。利用计算机图像处理技术和现代统计方法,能有效地对苦荞种子的颜色与形态特征进行精确量化和快速分析,可作为不同品种苦荞种子分类鉴别的一种客观,准确、有效的方法。     

MODELING THE SENSORY QUALITIES OF PROCESSED APPLES AFTER CONTROLLED ATMOSPHERE STORAGE AND FROZEN STORAGE1

Durational effects of controlled atmosphere storage (CA) and frozen storage on apple quality were studied for commercially processed pies made from Northern Spy, Idared and Nova Spy apples. Sensory tests on apple pie quality indicated that the duration of apples in CA significantly affected the quality of the processed apple. Extending the CA duration of the apples to 45 weeks resulted in a pie filling with reduced apple flavor, tartness and astringency, and with increased sweetness and off‐flavor. To minimize flavor/taste changes throughout the processing season, close attention must be given to the product's sugar/acid formulation: by week 27 for Idared apples and by week 33 for Northern Spy and Novaspy apples. The texture and appearance of processed Novaspy and Idared fruits were affected earlier in CA than Northern Spy apples. The frozen product was relatively stable for all three varieties, especially for apples processed early in the storage season (15–27 weeks). A strategy that utilizes short‐ to medium‐term CA with longer‐term frozen storage would optimize quality across the season.     

A COMBINATION OF HEAT TREATMENT AND CHITOSAN COATING DELAYS RIPENING AND REDUCES DECAY IN “GALA” APPLE FRUIT

ABSTRACT

Apples (Malus domestica Borkh. cv. Gala) were heat‐treated at 38C for 4 days (heat treatment [HT]) before or after coated with 1% chitosan (CTS). Following treatment, apples were stored at 0C for 8 weeks and 20C for 7 days as shelf life. The effectiveness of the combined treatments on the ripeness, quality and decay development caused by Penicillium expansum and Botrytis cinerea was evaluated. Severe heat damage was observed on the fruits heat‐treated after CTS coating (CTS + HT), appeared as external decay and internal brown after treatment. However, no damage on fruits heated before CTS coating (HT + CTS) during the whole storage. Besides the completely control of blue mold and gray mold on artificially inoculated fruits during storage, the HT + CTS treated fruit showed the lowest respiration rate, ethylene evolution, malondialdehyde and membrane leakage, and the highest firmness and consumer acceptance among the treatments. At the same time, this combined treatment could inhibit the lost of green color, titratable acidity and weight loss compared with HT alone.

PRACTICAL APPLICATIONS

“Gala” apple fruits become more popular in the world because of its high productivity and good quality. Hot air treatment alone has been used to delay ripening of Gala but caused the loss of peel green, titratable acidity and weight. This work investigated the effects of hot air treatment combined with chitosan (CTS) coating on the ripening, quality and decay development for Gala apple fruits. Compared with fruits heat‐treat alone, fruits heat‐treated before CTS coating (heat treatment + CTS) preserved original peel color, maintained titratable acidity and weight, completely control decay development and showed the highest consumer acceptance after storage. The information obtained from this study suggested that this combined treatment may be a suitable method for the commercial application on Gala apple fruits.     

COOKING CHARACTERISTICS OF FOUR CULTIVARS OF BAMBARA GROUNDNUTS SEEDS AND STARCH ISOLATE

The proximate composition and textural changes during the cooking of four bambara groundnut (Voandzeia subterranea) seed cultivars were evaluated. Bambara groundnut seeds contained 18–21% protein 6–8% fat, 8–10% moisture and 1.2–2.6% ash. Changes in hardness in relation to cooking time was monitored for 2 h. The cooking time for softening was shorter for the cream and brown colored cultivars than for the red black colored cultivars. The swelling and viscosity properties of starch isolates prepared form the seeds were studied. There were no varietal differences (p≤0.05) in starch viscosity and swelling properties among cultivars. Estimation of tannin content of bambara groundnut seeds showed that tannin contents of the red and black seed cultivars (0.96% and 1.1%, respectively) were significantly higher (p≤0.05) than the tannin contents of cream and brown seed cultivars (0.68% and 0.72%, respectively).     

Quality of Minimally Processed Apple Slices from Selected Cultivars

Twelve cultivars were prepared as slices and stored 12 days at 2°C. Changes in respiration and quality factors were compared. Initial respiration rates among cultivars varied from 3.5 mL CO₂/kg/hr in Delicious to 7.6 mL CO₂/kg/hr in Monroe and decreased rapidly during the first 3 days. Idared, McIntosh, Delicious, and Rome showed relatively low respiration throughout storage. Firmness of slices during storage decreased gradually for 7 days and more rapidly thereafter. Empire, Golden Delicious, and Idared apples showed minimum changes in firmness. Change in color of slices was rapid during the first 3 days. Cortland. Emuire. Golden Delicious. New York 674. and Delicious showed least browning. Titratable acidity, pH, soluble solids, and weight changes during storage were small and varied by cultivar. NY674, Cortland, Golden Delicious, Empire, and Delicious showed more desirable attributes for minimal processing.     

Non-destructive evaluation of apple maturity using an electronic nose system

Currently, random and destructive sampling techniques are used to evaluate apple quality. Thus there is need to develop a non-destructive technique to assess apple quality. Maturity indices such as starch index and puncture strength were used to categorize Gala apples into three maturity groups referred to as immature, mature and over mature fruits. Multivariate analysis of variance (MANOVA) of the electronic nose (EN) sensor data indicated that there were different maturity groups (Wilks’ Lambda F = 3.7, P < 0.0001). From the Discriminant analysis (DA), EN could effectively categorize Gala apples into the three maturity groups with the correct classification percentage of 83%.