PHYSICOCHEMICAL CHARACTERISTICS AND MINERAL CONTENT OF STRAWBERRIES GROWN IN SOIL AND SOILLESS SYSTEM

ABSTRACT

The main characteristics related to the nutritional quality were investigated in strawberry fruit cultivated in soilless systems (open and closed system) using peat, composted cork and coconut fiber like organic substrates. The values of compounds such as ash, humidity, acidity (TA) and pH, starch, reducing sugars (SS), total soluble solids (TSS), and minerals (calcium, potassium, sodium, magnesium, phosphorous, nitrogen, copper, iron, zinc and manganese) were determined. The results obtained for all parameters were compared statistically with those of traditional cultivation. Significant differences were observed between open and closed system in cork and coconut fiber for TSS, SS and SS/TA ratio. Differences in N, P, Ca, Mg, Zn and water content between the fruits from open and closed system were observed in coconut fiber. The two crop system, soil and soilless, had significantly different N and P contents, pH, TSS, SS, and sugars/acids (SS/TA) ratio. The strawberries cultivated in soil show higher values of pH, Ca, Zn, Fe, P, N, SS, TSS and SS/TA ratio. The discriminant functions that calculated applying discriminant analysis allow differentiation between the different groups of samples confirmed the role of minerals in the characterization of strawberries from different crop type using different systems or substrates.

PRACTICAL APPLICATIONS

Recently, soilless culture has known a strong development in the southern regions of Spain, France and Italy because of the phase out of methyl bromide. The interest in strawberry soilless culture is increasing every year, and the production area of strawberry soilless culture in Western Europe can be estimated around 1.270 ha. This article evaluates the chemical composition of strawberries cultivated in soilless system using several substrates. The results are important both for consumers who want to buy the best quality fruit, and for producers who want to develop sustainable production methods that increase the competitiveness of strawberry cultivation.

     

EFFECTS OF PHOMOPSIS PEACH ROT ON PULP LOSSES AND PUREE QUALITY

The effects of a Phomopsis sp. on four peach (Primus persica) cultivars and three fruit maturities were evaluated for pulp losses and quality changes of peach puree. Fruits were inoculated with 2 mm × 2 mm of agar with Phomopsis mycelium and incubated at room temperature (24 to 26 C) for 3 days. The early-maturing cultivar Goldilocks had higher susceptibility to Phomopsis than the late maturing Babygold 8. Mature fruit had a slightly higher degree of susceptibility to Phomopsis than less mature fruit, except for Goldilocks, which showed equal susceptibility at all maturity stages. Pulp losses, percentage of decayed tissue, titratable acidity, Howard mold counts, soluble solids (SS), SS/acid ratio, viscosity, pH and changes in color were variable among cultivars and maturities. Puree made with 1% or more Phomopsis-decayed tissue may be unacceptable because of a high (16–75%) mold count.     

Comparison of six cultivars of strawberries (<Emphasis Type="Italic">Fragaria x ananassa</Emphasis> Duch.) grown in northwest Poland

The aim of this study was to compare the value of Senga Sengana, a long-term standard cultivar, with other cultivars grown in northwest Poland, namely Dukat, Elkat, Selva, Elsanta and Kent. The fruits were obtained from a commercial plantation and cultivated by applying conventional farming practice. Among the strawberry cultivars studied Elsanta berries had the highest vitamin C content and its leaves the highest ellagic acid content. Kent berries had the highest contents of total sugar, total polyphenol, total anthocyanin and ellagic acid derivatives. Dukat berries had the highest dry weight and soluble solids content. Senga Sengana berries had a slightly higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging effect than other cultivars. Consumer-objective colour measurements were performed to evaluate the quality of the fruit. Elsanta and Elkat berries were found to have the highest L (lightness), a^* (redness), C^* (chromaticity) and h (hue angle) values.     

QUALITY EVALUATION OF MELON CULTIVARS. CORRELATION AMONG PHYSICAL-CHEMICAL AND SENSORY PARAMETERS

Soluble solid content, pH, firmness and color as measured by tristimulus colorimetry of nine cultivars of melon (Cucumis melo L.) were correlated with external appearance, texture and flavor. The Piel de Sapo type cultivars, RQ‐200 and Sancho, were the most appreciated for their external appearance, and MTV, a Rochet type cultivar, was preferred for its texture and flavor. ACL, a Yellow type cultivar, showed the highest pH and soluble solids (SS) content, while the Tendral type cultivars were the firmest. Flavor was positively correlated with pH and SS content, which confirms consumers’ preference for fruits with a high pH and high sugar content. The negative correlation between firmness and texture suggests that consumers prefer tender fruit. The colorimetric parameters served to differentiate three groups of cultivars as regards external color: Yellow type cultivars, Tendral type cultivars and Piel de Sapo and Rochet type cultivars. As regards internal color, none of the parameters clearly discriminated between the types of cultivars considered.     

Relationship of Quality Characteristics of Peaches (cv. Loring) to Maturity

The effect of maturity and ripening on the quality characteristics of Loring peaches was determined. Size, weight, Minolta a values, sucrose, total sugar, soluble solids (SS) and SS/TA ratio of cv. Loring peaches increased significantly with increased degree of maturity of fruit. Firmness, titratable acidity (TA) and delayed light emission (DLE) decreased significantly with increased maturity grade. The fruit of grades 1 and 2 did not attain sensory characteristics similar to tree ripe fruit (grades 6 and 7). The fruit of those grades were less sweet and more sour than grades 3-7. The optimum maturity for harvesting Loring peaches for optimum quality was maturity grade 5.     

Physicochemical Characteristics of 18 Cultivars of Nigerian Cowpeas (V. uniguiculafa) and Their Cooking Properties

Eighteen cultivars of cowpeas (V. unguiculata) were analyzed for cooking time, swelling capacity, leached solid, percent seed coat, seed density, amylose, tannins, proteins, and soluble sugars. The physicochemical characteristics varied with the seed coat color, the hilum color, and the skin texture. The cooking time was positively correlated to protein, seed density, percent seed coat, swelling capacity and leached solids, and negatively correlated to the levels of amylose, soluble sugars and tannins. There were significant correlations (p < 0.05) between sugars and swelling capacity, protein and seed density; and seed density and swelling capacity. The mean percent seed coat was significantly different (p < 0.05) between the varieties with wrinkled seed coats and those with smooth seed coats.     

Plum Juice Quality Affected by Enzyme Treatment and Fining

Juice from six plum (Primus domestica L.) cultivars, Au Red, Abundance, Pobeda, Shiro, Peach Plum and Early Golden, was extracted using 0.2% Clarex® L pectinase. The juice was processed as high temperature-short time (HTST)-unfined juice, fined juice or HTST-fined juice, and analyzed for yield, clarity, pectin content, soluble solids, pH, titratable acidity, color, sugars, total anthocyanins and total phenolics. Pectinase treatment resulted in 41–214% increase in juice yields, with highest increase for Au Red. Enzyme-extracted juice averaged 54% lower pectin than controls, and fining further reduced pectin. Enzyme treatment also improved juice soluble solids and color. A consumer type sensory panel indicated juice from Abundance, Pobeda and Peach Plum had best flavor and acceptability.     

不同品种番茄理化指标分析与研究

使用6种不同品种的番茄为实验原料,以可溶固形物含量、VC含量、番茄红素含量、色差为检测指标,分析各品种番茄中理化成分的含量,实验结果表明,里格尔87-5可溶固形物含量为5.3°Bx,其次为UC-82可溶固形物含量为5.1°Bx;不同品种间VC含量差异较大,其中UC-82中VC含量最高为28.9mg/100g;不同品种番茄番茄红素含量差异较大,其中里格尔87-5红素含量较高,可达到6.22mg/100g;在送样的6个品种番茄中,里格尔87-5的A值最大,色泽较好。     

INFLUENCE OF YEAR,CULTIVAR AND FRUIT MATURITY ON QUALITY OF PEACH PUREE1

A 3-year study was conducted to evaluate the effect of year, cultivar and fruit maturity on the quality of peach puree and to determine the relative importance (RI) of these factors on the quality components hue angle (color), pH, acidity, soluble solids (SS) and SS/acid ratio. The results indicated that year, cultivar and fruit maturity had a strong effect and that they are very important in determining the quality of peach puree by affecting the different quality components. In general, fruit maturity had stronger RI than year and cultivar on the quality parameters studied. The data obtained for different maturities and cultivars fit a linear regression that accounted for 95% of the variability for all quality parameters measured. pH and SS/acid ratio increased while acidity and hue angle decreased and SS showed small or no increase as the fruit reached more advance stages of maturity.     

PHYSICOCHEMICAL PROPERTIES OF FOUR TOMATO CULTIVARS GROWN IN NIGERIA

The physicochemical characteristics of tomato fruits from three commercial cultivars available in the local market were compared with a Wild cultivar. The results showed that the Ibadan‐Local and Wild cultivars had a higher fruit yield than Ife‐1 and Roma‐VF cultivars. The Wild cultivar has a high skin and seed content. The shape of the fruits varied from spherical to pear‐like. Physicochemical properties such as specific gravity, pH, titratable acidity, ash and refractive index did not vary significantly while total solids, longitudinal (stem→blossom end) and cross‐sectional diameters (transverse diameter), vitamin C and reducing sugars were significantly different (P > 0.05) among the cultivars investigated. The results showed that the Wild cultivar has attributes (i.e., physicochemical characteristics) comparable to commercial cultivars to recommend it to breeders for cultivation.     

2种草莓成熟过程中果实特征品质指标的变化

研究‘米拉’(‘Mira’)和‘哈尼’(‘Honeoye’)2个草莓品种的白色未熟期、粉色转熟期和红色成熟期3个阶段成熟过程中与风味、生理功能活性相关的特征品质指标变化。结果表明随着草莓成熟果实中总可溶性固形物含量、芳香性挥发成分、花色苷成分积累量有显著性上升,而总酸、总酚、总黄酮含量和抗氧化能力均有所下降。相关性和主成分分析结果表明,草莓成熟过程中总酚、总黄酮、总可溶性固形物和总酸含量均与总抗氧化-亚铁还原能力(ferric reducing-antioxidant power,FRAP)以及氧自由基吸收能力(oxygen radical absorption capacity,ORAC)的变化之间存在高相关性(r为0.859 1~0.994 7),而总花色苷含量与FRAP和ORAC之间的相关性仅为0.315 0和0.385 3。同时得出草莓果实的成熟度与芳香性挥发成分和花色苷组分积累量呈正相关性。     

Physicochemical and volatile profile alterations in pasteurized and frozen strawberry pulp during storage

This study evaluated the physicochemical characteristics and volatile profile of strawberry pulp subjected to factors, pasteurization (unpasteurized and pasteurized), freezing method (static air and forced air), and their interactions, during 12 months. Strawberry fruit were washed, sanitized, and pulped. The pulp was packaged, pasteurized, and frozen (0, 2, 4, 6, and 12 months). We concluded that pasteurization alters the strawberry pulp color. The impact of pasteurization and freezing method on the strawberry pulp pH, titratable acidity, and soluble solids variables is negligible. We tentatively identified 13 volatile compounds in fresh fruit and pulp, ethyl acetate, ethyl hexanoate, and linalool being the volatiles with the highest area percentage in the two products. The esters were predominant in both the fruit and strawberry pulp. Time is the most determining factor in modifying the strawberry pulp volatile profile, having an isolated effect on the increase of ethanol, ethyl butanoate, and linalool.

Practical applications

The strawberry is very used worldwide as raw material to different products, due to its color, flavor, and aroma. Thus, obtaining further information about the changes caused by processing and storage is of great importance for the food industry. This study shows the effect of simultaneous application of different processing techniques (pasteurization and freezing methods) on physicochemical variables and volatile profile of strawberry pulp over prolonged storage. Significant and unpublished results involving color, pH, acidity, soluble solids, and volatile compounds of strawberry frozen pulp over storage period are presented and may be applied for food industry to keep the pulp quality.     

Changes in the composition of aromatic compounds and other quality parameters of strawberries during freezing and thawing

Six strawberry cultivars were analysed, as fresh and as frozen and thawed fruit, for their content of anthocyanins, ascorbic acid, titratable acid, soluble solids and aromatic compounds. During freezing and thawing the content of titratable acid and soluble solids remained constant, whereas the content of anthocyanins and ascorbic acid decreased. The composition of aromatic compounds was also changed during freezing and thawing and greatest decreases were found fortrans-2-hexenal and hexanol. The content of volatile acids, linalool and methyl hexanoate was doubled after freezing and thawing, and, for all cultivars except from Pandora and Dania, ethyl butanoate and ethyl hexanoate increased strongly. This cultivar-dependent ethyl ester formation occurred during thawing rather than during freezing.     

Agronomic Characteristics and Chemical Composition of Newly Developed Day-Neutral Strawberry Lines by Agriculture and Agri-Food Canada

The agronomic characteristics and chemical composition of seven advanced day-neutral strawberry lines and a commercial cultivar ‘Seascape’ were evaluated for their horticulture and quality attributes. The results showed that the advanced strawberry lines had the best horticultural characteristics, such as more resistance to diseases, less weight and juice losses and better fruit glossiness during storage, compared to ‘Seascape’. Among the advanced lines, FIN005–55 had the better fruit quality with higher soluble solids content (SSC)/titratable acidity (TA) ratio and highest SSC, FIN005–7 had the highest total phenolic content (TPC) and antioxidant capacity (AC), and both had potential for commercial trials.     

STORAGE STABILITY OF STRAWBERRY JAM COLOR ENHANCED WITH BLACK CARROT JUICE CONCENTRATE

Black carrot juice concentrate was added to enhance the color of strawberry jams prepared from two locally grown cultivars, Osmanl? and Kara. Compared to other cultivars processed to jams, these two cultivars are lightly colored but very aromatic. Color and pigment stability of colored and noncolored (control) strawberry jams were studied during storage. The use of black carrot concentrate as a source of natural colorant stabilized the color of strawberry jam. The stabilization was more noticeable for jams prepared from Osmanl? cultivar. Monomeric anthocyanin degradation was fitted to a first‐order reaction model. Storage temperature had a strong influence on anthocyanin degradation. As the storage temperature increased, the stability of anthocyanins decreased significantly in both colored and noncolored jams. Parallel to decrease in monomeric anthocyanins, hue (h°) values of all jam samples increased throughout the storage. However, increase in h° values was much smaller in colored samples than in noncolored samples. High correlation was found between h° value and anthocyanin concentration at 22C (r = 0.910–0.978) and 37C (r = 0.931–0.981).     

RELATIONSHIP BETWEEN THE BOSTWICK MEASUREMENT AND FLUID PROPERTIES

Consistency of tomato concentrates was evaluated in a Bostwick consistometer. The concentrates were produced in a semibatch evaporator at soluble solids content from 5.3 to 24.0°Brix. The apparent viscosity, yield stress and density were measured at 20C. With respect to the gravity current analysis, the Bostwick measurement correlated well with the theoretical ratio of the apparent viscosity to density (R² = 0.96). For the concentrates with yield stress values in the range of 60–200 Pa, the predicted extent of flow based on the slump analysis was within 2% of the measured extent of flow in the Bostwick consistometer.     

Genotype and growing season influence blueberry antioxidant capacity and other quality attributes

Forty‐two blueberry cultivars (thirty‐six Vaccinium ashei, three V. ashei derivative hybrids and three northern highbush standards) were evaluated for their antioxidant capacities and other fruit quality attributes over two growing seasons. Total anthocyanins, phenolic content and antioxidant capacities varied substantially among species and cultivars. ‘Early May’ (V. ashei) had the highest amounts of anthocyanins, phenolics and antioxidant capacity. Cultivars from V. ashei hybrid derivatives had lower mean antioxidant components than those from northern highbush standards or V. ashei. The antioxidant capacity, as well as total anthocyanins and phenolics, had significant cultivar × year interactions. Correlation coefficient between years for total anthocyanins, total phenolics and oxygen radical absorbance capacity were high with values of 0.86, 0.81 and 0.93, respectively. Similar interactions were observed for soluble solids content (SSC), sugar, titratable acid and organic acids among cultivars both within and across the growing seasons. Correlation coefficients between years for SSC, fructose, glucose and sucrose were 0.78, 0.71, 0.83 and 0.96, respectively. Fructose and glucose were detected as two major sugars with sucrose as a minor constituent. ‘Clara’ contained the highest amounts of SSC and sugars, while ‘Satilla’ had the lowest. In general, V. ashei cultivars had a higher mean SSC and sugar contents than did the hybrid derivatives or the northern highbush standards. Cultivars of V. ashei contained higher malic acid than citric acid, whereas in hybrid derivatives and northern highbush cultivars, citric acid was the predominant organic acid. The diversity in the amount of these fruit quality attributes and antioxidant capacities presents a great opportunity for genetic improvement of blueberries through breeding programmes. The objective of the study was to identify blueberry cultivars with high antioxidant activity and good fruit quality, so they can be used as parents for future blueberry breeding programmes to develop new cultivars with higher antioxidant activity.     

CHANGES IN QUALITY CHARACTERISTICS DURING PEACH (CV. ‘MAJESTIC’) MATURATION1

Changes in the physical, chemical and sensory characteristics of peaches (cv. ‘Majestic’) were determined. Size, weight, ground color “a” values and SS/TA ratio increased significantly with increased degree of maturity; whereas, firmness, DLE, hue angle, titratable acidity, quinic acid, and citric acid decreased significantly. Malic acid increased significantly with maturity up to grade 5 then significantly decreased. In general sucrose content and total sugars increased through grade 6 and then decreased for tree ripe fruit. Sensory evaluation results showed no significant differences among maturity grades for sweet, sour, juice and overall peach flavor attributes. However, grade 1 and 2 fruit had lower scores for sweet and overall peach flavor attributes and tended to be more sour than grades 3–6 and tree ripe fruit. Correlation coefficients between maturity grade and all the selected quality parameters, except for the sour flavor attribute, were significant at the 1% level. DLE had the highest correlation with maturity grade followed by ground color “a” value, SS/TA ratio and firmness.     

Changes in physicochemical characteristics and volatile compounds of apricot (Prunus armeniaca L. cv. Bergeron) during storage and post-harvest maturation

The effects of storage and post-harvest maturation on the physicochemical characteristics and volatile constituents of Bergeron apricot were investigated during the 2007 season over two experiments. Fruits, harvested at two distinct stages of maturity, in two different experimental orchards, were stored in cold chambers at +1 °C for up to 3 weeks and then subjected to a post-harvest maturation in ripening chambers at 20 °C and 60–70% RH up to 7 days. Firmness, soluble solids (SS), titratable acidity (TA), and the levels of the main volatiles were determined. Physicochemical changes included a significant decrease of firmness during both storage and post-harvest maturation whereas the levels of SS and TA were found to be very similar. The results also indicated that, whatever their initial stage of maturity at harvest, the rates of softening of apricots during storage and/or post-harvest maturation were very comparable. During post-harvest maturation, the levels of C₆-compounds decreased drastically whereas, at the same time, those of esters, lactones and terpenic compounds greatly increased. During storage at 1 °C, a decrease of C₆-compounds was also observed. As regards other compounds, there were some statistically different results between samples but the changes observed for lactones, esters and terpenic compounds were relatively small in comparison to those observed during post-harvest maturation at 20 °C. The results also showed that, at the end, qualitative and quantitative differences can be observed in the “ready-to-eat” apricots according to their initial stage of maturity at harvest. On average, apricots harvested at the most advanced stage of maturity have, on average, the highest levels of soluble solids and the highest levels of volatile compounds of interest.     

RIPENING AND QUALITY CHANGES IN MANGO FRUIT AS AFFECTED BY COATING WITH AN EDIBLE FILM

Mango fruit has a relatively short storage life of about 2 to 3 weeks at 13C. In order to prolong the storage life of ‘Haden’ mangoes, fruit were coated with 3 concentrations (8,16 and 24 g.L^?1) of the edible coating film “Semperfresh” and then stored at 13C and 85% RH. Fruit were then evaluated every 4 days for up to 32 days for total soluble solids (TSS), titratable acidity (TA), pH, firmness, weight loss, color of the skin, and ascorbic acid content. All 3 concentrations applied to the fruit affected fruit ripening. TA, firmness, and green color were higher in coated fruit, and weight loss, SST, and pH were lower compared with the noncoated fruit. “Semperfresh” had no effect on decay development. Ascorbic acid decreased in all stored fruit, but this decrease was slower in coated fruit, and there were no significant differences between the different “Semperfresh” concentrations.