TEXTURE OF FRESH-PACK WHOLE CUCUMBER PICKLES: CORRELATION OF INSTRUMENTAL AND SENSORY MEASUREMENTS*

Correlations were determined between Texture Profile Analysis parameters of brittleness, hardness or total work of compression obtained with the Instron testing machine and sensory responses of firmness or crispness in evaluating texture of fresh-pack processed whole cucumbers (1-in. diam) of three ‘firm’ pickling cultivars (Explorer, Chipper, GY 3), two ‘soft’ pickling cultivars (Green F, Mincu) and a parthenocarpic slicer (MSU 6902 G). Further, correlations were determined between the TPA parameters and Magness-Taylor fruit pressure test (FPT) firmness. TPA hardness and total work correlated well with sensory responses; FPT firmness correlated satisfactorily with sensory firmness. Mean textural values from the various methods were compared with those obtained in the same manner for raw cucumbers. TPA brittleness tended to disappear in the processed fruit. Processing reduced mean TPA values across the six varieties to 35-58% of raw fruit values; it decreased mean FPT firmness to only 88%.     

TEXTURE OF SALT STOCK WHOLE CUCUMBER PICKLES: CORRELATION OF INSTRUMENTAL AND SENSORY MEASUREMENTS*

Correlations were determined between Texture Profile Analysis (TPA) parameters of brittleness, hardness or total work of compression obtained with the Instron testing machine and sensory responses of firmness or crispness in evaluating texture of fermented salt stock whole cucumbers (1-in. diam) of three ‘firm’ pickling cultivars (Explorer, Chipper, GY 3), two ‘soft’ pickling cultivars (Green F, Mincu) and a partheonocarpic slicer (MSU 6902 G). Correlations were also determined between the TPA parameters and Magness-Taylor fruit pressure test (FPT) firmness. Correlations were good between TPA parameters and FPT firmness. Correlations were poorer between instrumental and sensory methods due largely to inordinately high sensory scores assigned to salt stock of the slicer by all panelists. Mean textural values from the various methods were compared with those obtained in the same manner for raw cucumbers. TPA brittleness tended to disappear in salt stock. Processing reduced mean TPA values across the six varieties to 39-86% of raw fruit values. Mean FPT firmness was relatively unchanged at 99% that of raw fruit. Desalting from 16% down to 8 % or 4% NaCl reduced TPA values but increased FPT firmness.     

Maturity and ripening effects on chemical and sensory properties of apple juice

The effects of harvest maturity and ripening on the chemical composition and sensory characteristics of ‘McIntosh’ and ‘Spartan’ apple juice were evaluated. Juice was extracted from fruit harvested at seven weekly intervals beginning 3–4 weeks before commercial harvest and from fruit held in air storage (1°C) for 1 to 3 months. Internal ethylene concentration and starch index were used as maturity indices. Principal component analysis of juice data (pH. titratable acidity, organic acids, soluble solids, sugars, phenols, turbidity, and Hunterlab colour) showed a distinctive maturity effect on the characteristics of juice extracted from fruit immediately after harvest or after storage. Triangle testing showed aroma and flavour differences in both ‘McIntosh’ and ‘Spartan’ to be first discernable when ethylene was first detected (internal ethylene concentration ≥ 0.1 μl litre^?1) and starch hydrolysis evident (starch index 3.0–5.0 for ‘McIntosh’, 1.5–3.0 for ‘Spartan’), or after 2–3 months of air storage. Sensory profiling of fruity aroma, total aroma, fruit flavour by mouth, sweetness, and sourness in the juices showed increased fruitiness and sweetness and decreased sourness with advancing maturity.     

Tocopherol and tocotrienol compositions of raw table olive fruit

The tocopherol (Tp) and tocotrienol (Tt) compositions of raw Greek olive fruit pericarp were determined by high-performance liquid chromatography. The following four types of fruit collected from three main varieties of olive trees were analysed: ‘Conservolea’ (green), ‘Halkidiki’ (green), ‘Conservolea’ (black) and ‘Calamon’ (black). α-Tp was found to be the predominant Tp in all types. The variety and stage of maturity influenced the Tp and Tt composition. β-Tp and α-Tt were found only in trace quantities in green olives. The same was true for α-Tp in all types and γ-Tp in ‘Conservolea’ (green). The calculated α-Tp equivalents (Tp and Tt compositions expressed as α-Tp according to their relative biological activities) were 21·6, 29·7, 36·8 and 39·4 μg g^?1 pericarp or 138, 132, 189 and 196 μg g^?1 lipid for ‘Conservolea’ (green), ‘Halkidiki’ (green), ‘Conservolea’ (black) and ‘Calamon’ (black), respectively.     

Effects of variety, ripening condition and ripening stage on the quality of sulphite-free dried mango slices

The influence of cultivar and fruit ripeness on sensory properties and all-trans-β-carotene contents of dried mango slices was evaluated. Different ripeness stages, quantitatively defined by a ripening index (RPI), were generated from a single lot per cultivar by subjecting mature-green mangoes of the cultivars ‘Nam Dokmai’, ‘Kaew’, and ‘Chok Anan’ to different postharvest ripening regimes. Fruits were ripened for 2 and 3 days at 24±2 °C/45–60% relative humidity (RH) and 33±2 °C/50–70% RH, with application of calcium carbide (CaC₂) or 2-chloroethylphosphonic acid (CEPA, Ride^®) beside the control, terminating postharvest ripening when fruit firmness allowed proper peeling and slicing. After ripening, fruits were washed, peeled, sliced and subsequently dried in a conventional tray dryer at 70 °C for 8–10 h, until the water activity of the dried fruits was below 0.65. Mangoes cv. ‘Kaew’, followed by ‘Chok Anan’, were more suitable for drying than cv. ‘Nam Dokmai’ because of superior all-trans-β-carotene contents of the products. Maximum β-carotene contents of dried mango slices from cvs. ‘Chok Anan’ and ‘Kaew’ corresponded to retinol equivalents of 333–383 and 483–905 per 100 g of edible portion (dry weight), meeting daily mean requirements of vitamin A for adults according to FAO/WHO. Similar to the fresh fruit, exponential rise of all-trans-β-carotene contents with increasing fruit ripeness was also observed for the dried products of cvs. ‘Nam Dokmai’ and ‘Chok Anan’. Consistently, accelerated ripening at 33 °C, instead of 24 °C, resulted in higher all-trans-β-carotene contents of dried fruits. Both good sensory acceptance and cultivar-specific maximum all-trans-β-carotene contents of 13–16 and 20–23 mg kg^?1 usually characterised the products of ‘Nam Dokmai’ and ‘Chok Anan’ fruits with RPI levels between 3 and 4. Conversely, fruits cv. ‘Kaew’ of RPI levels above 6 generally yielded products inferior in sensory acceptance and β-carotene contents, while superior product quality was found at higher RPI levels than for the other two cultivars.     

Fruit dry matter concentration: a new quality metric for apples

BACKGROUND: In the fresh apple market fruit must be crisp and juicy to attract buyers to purchase again. However, recent studies have shown that consumer acceptability could be further enhanced by improving taste. This study evaluates the use of fruit dry matter concentration (DMC) as a new fruit quality metric for apple. RESULTS: Fruit samples collected at harvest, in the two main fruit growing regions of New Zealand, showed a variation in mean fruit DMC from 130 to 156 g kg^?1 with ‘Royal Gala’ and with ‘Scifresh’ from 152 to 176 g kg^?1. Individual fruit DMC showed a larger range, from 108 to 189 g kg^?1 with ‘Royal Gala’ and from 125 to 201 g kg^?1 with ‘Scifresh’. Fruit DMC proved a more reliable predictor of total soluble solids after 12 weeks of air storage at 0.5 °C than TSS at harvest for both ‘Royal Gala’ and ‘Scifresh’. Fruit DMC was also positively related to flesh firmness, although this relationship was not as strong as that seen with soluble solids and was more dependent on cultivar. Consumer studies showed that consumer preference was positively related to fruit DMC of ‘Royal Gala’ apples. CONCLUSION: Fruit DMC can therefore be measured before or at harvest, and be used to predict the sensory potential for the fruit after storage. Copyright © 2010 Society of Chemical Industry     

Evaluation of the EEC four-plate test and Premi test for screening antibiotic residues in trout (Salmo trutta)

The four‐plate test (FPT) method was used for the determination of sulfadiazine/trimethoprim residues in trout in the European Community (EC). This microbiological inhibition test used three media seeded with Bacillus subtilis at different pH values (6, 7.2 or 8.0) and a fourth medium seeded with Micrococcus luteus. The Premi test was also used for the determination of sulfadiazine/trimethoprim residues in trout. The effects of a trout muscle supernatant on detection limits of antibiotics with microbiological inhibition tests were measured. The supernatant was applied directly on top of the paper disks impregnated with aqueous antibiotic solutions. Inhibition zones were compared with those obtained by the same standard solution of sulfadiazine/trimethoprim without the trout supernatant. The detection limit of penicillin, sulfadimidine, streptomycin groups of antibiotics were determined for checking the test plates. For supernatant from fish fed with pellets containing antibiotics (sulfadiazine/trimethoprim), the inhibition zones increased according to the duration of the feed application. In the control group, no inhibition zones were detected. The concentration of the residues accumulated and reached a plateau after 5 days. The antibiotics were detectable in the same concentration as on day 7, but three days later (on day 10) they were no longer detectable in the fish samples. In contrast to the ‘FPT’, 3 days after discontinuing the medicated diet, there were still residues detectable by ‘Premi test’ on day 10. Data is presented that shows that the FPT and the Premi test methods are very useful for the determination of sulfadiazine/trimethoprim residues in trout.     

Phenolic and carotenoid profiles of papaya fruit (Carica papaya L.) and their contents under low temperature storage

BACKGROUND: Tropical fruits are rich in phenolic and carotenoid compounds, and these are associated with cultivar, pre‐ and postharvest handling factors. The aim of this work was to identify major phenolics and carotenoids in ‘Maradol’ papaya fruit and to investigate their response to storage temperature. RESULTS: Ferulic acid, caffeic acid and rutin were identified in ‘Maradol’ papaya fruit exocarp as the most abundant phenolic compounds, and lycopene, β‐cryptoxanthin and β‐carotene were identified in mesocarp as the major carotenoids. Ranges of contents of ferulic acid (1.33–1.62 g kg^?1 dry weight), caffeic acid (0.46–0.68 g kg^?1 dw) and rutin (0.10–0.16 g kg^?1 dw) were found in papaya fruit, which tend to decrease during ripening at 25 °C. Lycopene (0.0015 to 0.012 g kg^?1 fresh weight) and β‐cryptoxanthin (0.0031 to 0.0080 g kg^?1 fw) were found in fruits stored at 25 °C, which tend to increase during ripening. No significant differences in β‐carotene or rutin contents were observed in relation to storage temperature. CONCLUSION: Phenolics and carotenoids of ‘Maradol’ papaya were influenced by postharvest storage temperature with exception of β‐carotene and rutin. Ripe papaya stored at 25 °C had more carotenoids than those stored at 1 °C. Low (chilling) temperature (1 °C) negatively affected the content of major carotenoids, except β‐carotene, but preserved or increased ferulic and caffeic acids levels, as compared to high (safe) temperature (25 °C). Copyright © 2010 Society of Chemical Industry     

18 个品种授粉‘鸭梨’果实品质和香气成分分析与评价

研究不同品种授粉对‘鸭梨’果实品质和香气成分的影响,探究‘鸭梨’果实品质性状的花粉直感效应,为授粉品种筛选和‘鸭梨’果实品质改善提供依据。以30 a生‘鸭梨’为试材,分别以18 个不同品种特性花粉为‘鸭梨’进行人工授粉,其中以‘雪花梨’授粉果实为对照,测定果实单果质量、果点直径、果点密度、石细胞团含量、可溶性固形物、糖酸组分含量及香气组分相对含量等品质指标,利用主成分分析对不同品种的授粉效果进行综合评价。结果表明,不同品种授粉对‘鸭梨’果实外观品质、内在品质及香气成分均有影响,变幅在12.57%～96.10%之间;与‘雪花梨’授粉果实相比,‘南水’、‘丰水’和‘库尔勒香梨’授粉‘鸭梨’果实可溶性固形物、可溶性糖含量和固酸比均显著提高,分别提高了0.55%～0.76%、7.53～16.54 mg/g和1.96～4.54,改善‘鸭梨’果实营养品质;‘南水’、‘库尔勒香梨’、‘Crispel’、‘绿宝石’和‘翠玉’授粉‘鸭梨’果实酯类物质相对含量显著增加了7.77～17.85 倍,其中乙酸己酯相对含量显著提高了2.76～14.86 倍,同时检测出6 种特有酯类香气物质,分别为乙酸乙酯、己酸乙酯、丁酸乙酯、(E)-乙酸-2-己烯-1-醇酯、乙酸苯乙酯和反-2-顺-癸二烯酸乙酯,改善‘鸭梨’果实香味。与父本果实品质特性相比,授粉‘鸭梨’果实在石细胞团含量、果肉质地、可溶性固形物、可溶性糖及香气组分方面表现明显的花粉直感效应,而在单果质量、果点直径、果点密度及总酸含量方面无明显花粉直感效应;综合评价表明,‘南水’授粉效果最好,适宜为‘鸭梨’授粉树。     

Perception of flavour in standardised fruit pulps with additions of acids or sugars

We hypothesised that adding sugars or acids to pulps derived from fruit of different genetic background, or of lower or higher carbohydrate status should give similar results until a threshold for sweetness or acidity perception in the pulp background was reached. Pulps made from fruit of Actinidia deliciosa ‘Hayward’—a fresh sweet-acid kiwifruit—and A. chinensis ‘Hort16A’—a sweet tropical flavoured kiwifruit, were compared. Flavour volatiles and background sugar and acid composition differed between the two fruit. Using high (14.1–14.5%) or low (11.5–11.9%) soluble solids (SS) pulps, trained tasters perceived added sugar as sweeter, confirming earlier research with consumers. Added acids (7 mmoles H⁺ 100 g⁻¹) reduced perceptions of sweetness and tasters perceived quinic acid to have a strong impact on the pulps tasted, resulting in a greater perception of acidity than addition of citric, ascorbic or malic acids. However perceptions of acidity also depended on background pulp composition. Addition of sugar or acid to pulps affected measured headspace volatiles. Volatile compounds affected included mid-chain length aldehydes, alcohols and esters, but only a few showed significant alteration. For example, hexanal, (E)-3-hexen-1-ol and (Z)-3-hexenol increased significantly when malic acid was added to ‘Hayward’ pulps. We suggest that the release of alcohols was associated with change in acidity and pulp metabolism rather than a ‘salting out’ effect. Perceived changes to banana and lemon flavours with both sugar and acid addition appear to be due to interactions in taster mouths or associated memories rather than release of specific volatiles.     

Tentative zinc biofortification of banana fruit via bunch spray and bunch stalk feeding

Due to the importance of banana consumption in developing countries and producing zinc-rich foods, the objective of this study was to evaluate the feasibility of banana bunch sprays and bunch stalk feeding with Zn aiming to biofortify this fruit. Zn sprays were carried out with a dose of 80 g ha⁻¹ using ZnCl₂ and ZnCl₂ combined with a chelating agent in two banana cultivars (‘Maravilha’ and ‘FHIA 18’). Bunch stalk feeding with Zn was carried out by fixing plastic bags on the stem end containing solutions of ZnSO₄ (0, 0.5, 1.0 and 2.0 g L⁻¹) in two banana cultivars (‘Williams’ and ‘Prata Anã’). Both strategies resulted in a maximum fruit Zn content of 0.14 mg 100 g⁻¹. Although it was possible to increase the Zn content in banana fruit from ‘FHIA 18’ and ‘Prata Anã’ cultivars, both strategies did not result in biofortified banana fruit with a Zn level which would fulfil the Zn dietary reference intake (DRI) of 2 mg dia⁻¹ for children. Banana bunch sprays with Zn did not affect the fruit quality, but bunch stalk feeding with Zn resulted in fruits with lower ratio, pH and ascorbic acid content.     

Effects of exogenous nitric oxide on contents of soluble sugars and related enzyme activities in 'Feicheng' peach fruit

BACKGROUND: Sugar content is one of the main characteristics related to the quality of fruit. Research confirms that nitric oxide (NO) involves a physiological process and prolongs the storage life of fruit. However, little attention has been paid to the effects of NO on sugar metabolism in fruit during storage. In this study, the effect of different concentrations (0, 10, 30 µmol L^?1) of exogenous NO treatment on sugar content and related enzyme activities in ‘Feicheng’ peach fruit was investigated during storage (0–12 days after harvest) at room temperature (25 °C). RESULTS: Results showed that the decrease of firmness and accumulation of sugar and acid:sugar ratio in peach fruit during storage were significantly inhibited by treatment with 10 µmol L^?1 NO. Treatment with 10 µmol L^?1 NO could promote fructose and glucose metabolism during the first 4 days of storage, and increase the content of sucrose and the activities of sorbitol dehydrogenase, sorbitol oxidase and sucrose phosphate synthase in peach fruit during storage. However, acid invertase activity from 8 to 12 days of storage and neutral invertase activity during the first 4 days of storage were inhibited by treatment with 10 µmol L^?1 NO. At the same time, treatment with 10 µmol L^?1 NO inhibited sucrose synthase (SS) activity in decomposition during storage and SS activity in synthesis from 8 to 12 days of storage. CONCLUSION: Treatment with 10 µmol L^?1 NO had a significant impact on content of soluble sugars and related enzyme activities in ‘Feicheng’ peach fruit during storage (0–12 days) at room temperature (25 °C). Copyright © 2011 Society of Chemical Industry     

No improvement in fruit quality through chemical flower thinning in sweet cherry (Prunus avium L.)

BACKGROUND: Chemical flower thinning with ammonium thiosulfate (ATS) was applied on branches of sweet cherry (Prunus avium L.) cultivars ‘Blaze Star’, ‘Samba’, ‘Techlovan’ and ‘Merchant’ (all grafted on GiSelA 5) in a two‐year field study in 2006 and 2007. Different concentrations of ATS (8.82 and 17.64 g L^?1) and different application times were studied. Fruit quality parameters analysed included crop load, fruit size, fruit weight, flesh/stone ratio, content of soluble solids, pH value and content of titratable acids. RESULTS: Crop load was significantly affected (P < 0.01) by application, cultivar and year. Fruit size, fruit weight and content of titratable acids were not improved by any of the application strategies. An influence of cultivar and application on pH value was observed (P < 0.05). Flesh/stone ratio was significantly enhanced (P < 0.05) in ‘Blaze Star’ only, while content of soluble solids was significantly affected in ‘Techlovan’ only in 2007. CONCLUSION: No general improvement in quality parameters was achieved by chemical flower thinning in the P. avium cultivars studied over a two‐year field experiment. Copyright © 2009 Society of Chemical Industry     

Mechanical flower thinning improves the fruit quality of apples

BACKGROUND: Apple ‘Golden Delicious Reinders’ and ‘Gala Mondial’ trees were mechanically blossom‐thinned with 30–77 × g (300–480 rpm rotation) and 5 or 7.5 km h^?1 vehicle speed to improve fruit quality, minimise leaf damage, reduce hand and chemical thinning and to prevent or overcome alternate bearing; adjacent untreated or manually thinned apple trees served as controls. RESULTS: Mechanical thinning (43 × g, 360 rpm, 5–7.5 km h^?1) had a positive effect on fruit size (15% larger), firmness (8.4 in Gala vs. 7.6 kg cm^?2 in the unthinned control), sweetness (124 vs. 117 g kg^?1 sugar in the control), contained the largest malic acid content (4 g kg^?1 vs. 3.4 g kg^?1 in the control) and 17% more anthocyanin (normalised anthocyanin index = 0.8 in Gala vs. 0.7 in the control); fruit of Golden and Gala showed additionally advanced starch breakdown and ripened earlier. CONCLUSIONS: Since increases in rotor speed, viz. centrifugal force, versus increases in the vehicle speed resulted in opposing effects, an integrated coefficient of thinning (ICT) was devised with optimum values of 10–40 (at 43 × g, 5–7.5 km h^?1), where an ICT > 50 led to tree damage and ICT < 8 led to sub‐optimum thinning efficacy. Copyright © 2010 Society of Chemical Industry     

Physicochemical Changes in Seven Tomato (Lycopersicon esculentum) Cultivars During Ripening

Seven tomato cultivars were studied for compositional changes during ripening at green, breaker, turner, and ripe stages. Result indicated changes in total soluble solids (4.15 to 6.62 g/100 g), acidity (0.36 to 0.54 g/100 g), reducing sugars (0.76 to 4.04 g/100 g), total sugars (1.67 to 5.52 g/100 g), lycopene in skin (0.07 to 14.28 mg/100 g), and in pulp (0.04 to 6.73 mg/100 g) during ripening from green to red ripe stage. Cultivar UC-828 was found superior with respect to total soluble solids (6.62 g/100 g), reducing sugars (4.04 g/100 g), and total sugars (5.52 g/100 g) where as cultivar 8–2–1–2–5 was found superior with respect to lycopene in skin (14.28 mg/100 g) and in pulp (6.73 mg/100 g). Hunter color values showed a change from negative value of ‘a’ (greenness) to positive values (redness) where as ‘b’ decreased. The (b/a) and tan^?1 (b/a) showed a similar pattern of first increased and then decreased. The puncture resistance was decreased from 10.5 to 2.3 N indicating softening during ripening. Correlation studies showed that lycopene content best correlated with Hunter ‘a’ values during ripening (R² = 0.84 to 0.93). Intercultivar variation in physicochemical parameters at all stages of ripening revealed that Castle Rock was the best cultivar.     

梨质地变化规律与动力学模型

为了研究梨在采后贮藏过程中质地变化规律以对可食用期评估,实验测定了‘黄金’、‘玉冠’和‘丰水’3 个品种梨在贮藏过程中泰勒（Magness-Taylor,MT）硬度、果肉硬度、果肉弹性率和感官总体可接受度的变化,并建立了质地参数变化的动力学模型。结果表明：MT硬度、果肉硬度、果肉弹性率总体上均随贮藏时间延长逐渐降低,但果肉弹性率对贮藏时间变化的灵敏性优于MT硬度和果肉硬度,且果肉弹性率与感官总体可接受度的相关性更强;采用零级和一级动力学模型、Logistic模型和威布尔模型对各质地参数拟合,结果均是威布尔模型的拟合结果最佳;通过威布尔模型和感官评定,得到‘黄金’、‘玉冠’和‘丰水’梨的MT硬度分别低于14.762、10.411 N和7.255 N,果肉硬度分别低于8.215、7.438 N和5.181 N,果肉弹性率分别低于4.571、5.572 N/mm和3.609 N/mm后不具备商品价值,不建议食用。研究结果可为梨的贮藏和食用提供指导依据。     

Effect of cultivar and fruit storage on basic composition of clear and cloudy pear juices

BackgroundPears due to low acidity are a suitable raw material for the production of multifruit nectars thus it is justified to determine the chemical composition and investigate the effect of cultivar and fruit maturity on juices quality.MethodsJuices from ‘Alexander Lucas’ and ‘Conference’ cultivars were produced after harvest and after 3 months of pears storage.ResultsAverage yield of clear juices was 76.4% for ‘Conference’ cultivar and 74.3% for ‘Alexander Lucas’. In the case of cloudy juices, the yield was lower by about 3%. Processing of ‘Conference’ cv. from stored fruit resulted in yield decrease compared to fruits after harvest; this was not in case of ‘Alexander Lucas’ in 2008, where juices produced from stored fruits were characterized by a higher yield compared to fresh fruit.Total solids content in clear juices was 125–135 g/L and 135–141 g/L for cloudy juices. ABTS^●+ and total phenolics analysis showed that cloudy juices were characterized by a higher antioxidant activity and phenolics content than the clear ones.ConclusionPear storage, on the contrary to apples, does not decrease their suitability for cloudy juice production. Cloudy juices as a rule have higher antioxidant activity than the clear ones.     

How to prevent ripening blockage in 1-MCP-treated 'Conference' pears

BACKGROUND: Some European pear varieties treated with 1‐methylcyclopropene (1‐MCP) often remain ‘evergreen’, meaning that their ripening process is blocked and does not resume after removal from cold storage. In this work this was confirmed also to be the case in ‘Conference’ pears. To reverse the blockage of ripening 1‐MCP treatments combined with external exogenous ethylene were tested. RESULTS: 1‐MCP treatment of ‘Conference’ pears is very effective in delaying ripening and, more specifically, softening. The same 1‐MCP concentration in different experimental years caused a different response. The higher dose of 1‐MCP (600 nL L^?1) always resulted in irreversible blockage of ripening, whereas the behaviour of fruit receiving a lower dose (300 nL L^?1) depended on the year, and this did not depend on maturity at harvest or on storage conditions. Simultaneous exposure to 1‐MCP and exogenous ethylene significantly affected fruit ripening, allowing significant softening to occur but at a lower rate compared with control fruit. CONCLUSION: The application of exogenous ethylene and 1‐MCP simultaneously after harvest permitted restoration of the ripening process after storage in ‘Conference’ pears, extending the possibility of marketing and consumption. Copyright © 2011 Society of Chemical Industry     

Effect of solid content and composition of hydroxypropyl methylcellulose-lipid edible coatings on physico-chemical and nutritional quality of 'Oronules' mandarins

BACKGROUND: Citrus fruit represent an important source of vitamin C, as well as other bioactive compounds. Edible coatings have the potential to extend shelf life of citrus by providing a semi‐permeable barrier to water and gases, which depends on coating composition, solid content (SC), and cultivar. However, little is known about the effect of coatings on citrus nutritional quality. This work studies the effect of coating composition and SC of hydroxypropyl methylcellulose (HPMC)–beeswax (BW)–shellac coatings on the physico‐chemical, sensory and nutritional quality of ‘Oronules’ mandarins. Coatings prepared at the same lipid content differed in the BW:shellac ratio (1:3 and 3:1) and SC of the formulations (40 and 80 g kg^?1). RESULTS: The coating with 1:3 BW:shellac ratio and 80 g kg^?1 SC was the most effective controlling weight loss, although it was less effective than the commercial wax tested. Increasing SC had a greater effect than the BW:shellac ratio in fruit internal atmosphere and sensory quality, with the presence of off‐flavour when coatings were applied at 80 g kg^?1 SC. Nutritional quality was not affected by the application of the different treatments. CONCLUSION: HPMC–lipid coatings have the potential to extend shelf life of ‘Oronules’ mandarins. However, care should be taken controlling formulation SC to avoid the build‐up of off‐flavour. Copyright © 2011 Society of Chemical Industry     

Effects of 1‐MCP applied postharvest on epicuticular wax of apples (Malus domestica Borkh.) during storage

BACKGROUND: Certain apple cultivars develop a greasy feel when overripe. Treating fruits with the ripening inhibitor 1‐methylcyclopropene (1‐MCP, SmartFresh^™) reduces fruit greasiness. This study examines the nature of this phenomenon. ‘Royal Gala’ apples were treated with 1‐MCP at 1.0 µl L⁻¹ following harvest. Periodically, during storage at − 1 °C for up to 6 months, fruits were evaluated for internal ethylene concentration, fruit epicuticular wax morphology (using scanning electron microscopy) and non‐polar organic solvent‐extractable (NPOSE) wax constituents of the cuticle (using gas chromatography/mass spectrometry). RESULTS: In 2004, 1‐MCP strongly inhibited internal ethylene production; however, total weight of NPOSE wax during storage was unaffected by treatment. In 2005, several wax constituents present in both ‘Autumn Gold’ and ‘Royal Gala’ showed differences during storage. In 2006, cuticular wax constituents comprising 80% of the total from ‘Royal Gala’ showed no treatment differences. Although several minor constituents did exhibit differences within treatment and sampling date, these did not appear sufficient to cause the subtle differences in surface wax morphology. CONCLUSION: 1‐MCP strongly inhibited ethylene production and delayed development of certain wax constituents thought responsible for fruit greasiness during cold storage. Subtle differences in surface wax morphology appeared unrelated to wax production. Published in 2008 by John Wiley & Sons, Ltd.