Sugar Content Of Juice Research Articles

Rapid and nondestructive detection of watercore and sugar content in Asian pear by near infrared spectroscopy for commercial trade

Watercore and sugar content are internal qualities which are impossible for exterior determination. Therefore the aims of this study were to develop models for nondestructive detection of watercore and predicting sugar content in pear using Near Infrared Spectroscopy (NIR) technique. A total of 93 samples of Asian pear variety "SH-078" were used. For sugar content, spectrum of each fruit was measured in the short wavelength region (700–1100 nm) in the reflection mode and the first derivative of spectra were then correlated with the sugar content in juice determined by digital refractometer. Prediction equation was performed by multiple linear regression. The result showed Standard Error of Prediction (SEP) = 0.58°Bx, and Bias=0.11. The result from t-test showed that sugar content predicted by NIR was not significantly different from the value analyzed by refractometer at 95% confidence. For watercore disorder, NIR measurement was performed over the short wavelength range (700–850 nm) in the transmission mode. The first derivative spectra were correlated with internal qualities. Then principle component analysis (PCA) and partial least squares discriminant analysis (PLSDA) were used to perform discrimination models. The accuracy of the PCA model was greater than the PLSDA one. The scores from PC1 were separated into two boundaries, one predicted rejected pears with 100% classification accuracy, and the other was accepted pears with 92% accuracy. The high accuracy of sugar content determining and watercore detecting by NIR reveal the high efficiency of NIR technique for detecting other internal qualities of fruit in the future.

It is not worthwhile to fertilize sweet sorghum (Sorghum bicolor L. Moench) with cattle slurry: Productivity and nitrogen-use efficiency

Sweet sorghum (Sorghum bicolor L. Moench) is a viable alternative to maize when irrigation water is unavailable or too expensive. In areas with intensive livestock activities animal slurries are predominantly applied to maize. Although sweet sorghum is fairly investigated species, little is know about the efficiency with which the crop can use nitrogen (N) applied in the form of cattle slurry. Then, a field experiment was devised to explore the following research questions: (i) what is the effect of cattle slurry and industrial fertilizers on sweet sorghum productivity? (ii) which is the N-use efficiency for cattle slurry and industrial fertilizers applied to sweet sorghum? The study was conducted in the years from 2008 to 2012 (five years) in the alluvial plain of the Po Valley, Northern Italy. The fertilization treatments applied annually were: (i) no fertilization (control); (ii) industrial fertilizers 120kgNha−1, applied in the form of urea, +52kgP ha−1, applied in the form of superphosphate, (IF); (iii) cattle slurry 10mm, i.e. 10Lm−2 (CS10); and (iv) cattle slurry 20mm, i.e. 20Lm−2 (CS20). The indigenous soil N supply varied from 112 to 243kgNha−1. The experiment was not irrigated. The observed average annual yields were, in decreasing order: 34.6MgDMha−1 in 2008, 31.7 in 2011, 29.5 in 2009, 27.9 in 2010 and 27.2 in 2012. Physiological efficiency applied N (PEN, kg yield increase per kgN uptake), recovery efficiency applied N (REN, kgN uptake increase per kgN applied) and agronomic efficiency of applied N (AEN, kg yield increase per kgN applied) were evaluated in this study. In the range of observed values the PEN was 63kg DM yield per kgN uptake, the REN varied from 0 to 0.33 and the AEN was zero in all the years of experiment. Fertilization tends to increase N uptake but not yield nor stem juice sugar content. Our findings indicate that under conditions of good soil fertility, sweet sorghum should be considered poorly suited to receive cattle slurry application, due to the absence of yield gain and to the low N-use efficiency. Moreover, the high N uptake achieved by the crop with no fertilization, combined with the modest REN suggest the animal slurry should rather be applied to crops possessing higher efficiency in utilizing N applied with fertilizers. Nevertheless, the frugality of sweet sorghum should be considered a virtue in the light of the increasing interest in reducing the input for energy crop production.

Determining Effects of Sowing Time and Nitrogen Fertilizer Rate on Brix of Sweet Sorghum Using a Gear-Type Extractor

Sweet sorghum is an attractive energy crop, but the short harvest window and the poor storability of stalks and sugar juices are obstacles in the production of ethanol from sweet sorghum. The sugar content and harvest window of sweet sorghum are very important for ethanol yield and the operating rate of an ethanol production plant. To avoid sugar degradation, the sugar content of sweet sorghum juice needs to be measured immediately after juice extraction from the whole plant. A gear-type extractor suitable for the whole sweet sorghum plant was designed, fabricated, and tested for precise and convenient determination of the sugar content of sweet sorghum. The mean extraction speed of the developed extractor was 9.3 s plant-1. The effects of sowing time and nitrogen fertilizer rate on the sugar content and harvest window were investigated. The sugar contents of sweet sorghum sown on May 1, June 1, and July 3 applying 70 kg ha-1 nitrogen fertilizer and of sweet sorghum sown on May 29 applying 70, 140, and 210 kg ha-1 nitrogen fertilizer were determined using the developed extractor. Brix exceeded 10% for around 30 and 60 days for sweet sorghum sown in May and July, respectively. The sugar content of the juice from sweet sorghum with 70 kg ha-1 N fertilizer applied was higher than that of sweet sorghum with 210 kg ha-1 N fertilizer applied. The results indicate that the later sowing and the lower nitrogen fertilizer rate could prolong the harvest window of sweet sorghum. The harvest window of sweet sorghum used as a feedstock for ethanol production was prolonged to three months by sowing twice and applying 70 kg ha-1 nitrogen fertilizer in one year in Tottori, Japan (35 32' N, 134 10' E).

Juice, sugar, and bagasse response of sweet sorghum (Sorghum bicolor (L.) Moench cv. M81E) to N fertilization and soil type

AbstractThe objective of this research was to determine the optimum nitrogen fertilizer rate for producing sweet sorghum (a promising biofuel crop) juice, sugar, and bagasse on silt loam, sandy loam, and clay soils in Missouri. Seven nitrogen fertilization rates were applied, ranging from 0 to 134 kg N ha−1. Regardless of the soil and year, the juice content of sweet sorghum stalk averaged 68.8% by weight. The juice yield ranged from 15.2 to 71.1 m3 ha−1. Soil and N rate significantly impacted the juice yield (P < 0.0001). The pH and the density of the juice were not affected by the soil or N. The sugar content (Brix) of the juice varied between 10.7% and 18.9%. N fertilization improved the sugar content of the juice. A negative correlation existed between the sugar concentration and the juice yield. In general, the lowest sugar content was found in the clay soil and the impact of the N fertilization on juice sugar content was most pronounced in that soil. The juice sugar yield ranged between 2 and 9.9 Mg ha−1, with significant differences found between years, N rates, and soils. N fertilization always increased the sugar yield in the clay soil, whereas in loam soil, a significant sugar response was recorded when the sweet sorghum was planted after corn. The average juice water content was 84% by weight. The dry bagasse yield fluctuated between 3.2 and 13.8 Mg ha−1 with significant difference found with N rate, soil, and year. When sweet sorghum was grown after soybean or cotton, its N requirement was less than after a corn crop was grown the previous year. In general, a minimum of 67 kg N ha−1 was required to optimize juice, sugar, and bagasse yield in sweet sorghum.

Parental combining ability as a good predictor of productive crosses in sweet sorghum [Sorghum bicolor (L.) Moench

The exploitation of heterosis through the development and deployment of hybrids for commercial cultivation is one of the effective approaches for genetic enhancement of crop plants for traits of economic importance. Developing an objective criterion of choosing the parents for developing and testing hybrids is essential for maximizing the success of heterosis breeding. A set of 18 crosses produced from parents differing in their gca effects for bio-energy traits such as millable cane yield, juice volume and juice sugar content (as indicated by Brix %) were evaluated in replicated trial in the experimental plots of the Department of Genetics and Plant Breeding, University of Agricultural Sciences, Bangalore during 2006-07. The utility of parental general combining ability for producing high frequency of superior crosses for a set of bio-energy traits in sweet sorghum was investigated. The study suggested that parents with contrasting gca effects produce crosses with higher sca and heterotic potential for the bio-energy traits. The use of female parents with higher gca effects is important for realizing greater probability of crosses with sca effects and heterosis in desirable direction for bio-energy traits.

Phenometric studies on stalk juice and sugar contents of silo sorghum types

Bioenergies (among them e.g. bioalcohol) can be solutions for the replacement of fossil fuels. For its production, plants with high sugar or starch content can be used. Juice pressed from the stalk of sugar sorghum has high sugar content (14-17%) that makes it suitable for bioethanol production. During our experiment, we examined 53 restorer male lines; among them 22 were silo type sugar sorghum. We studied the following traits: plant height, breeding time, level of foliation, stalk diameter, characteristics of stalk medulla, juice content of stalk, sugar content of stalk juice. According to examined characteristics, we selected six restorer male lines for studies in the forthcoming years: RL 1, RL 2, RL 3, RL 4, RL 5, RL 9, RL 12, RL 15, RL 18. Their stalk medullas were wet, stalk diameters were medium-thick, sugar contents of juices varied between 17 and 24% at the end of milk mature. Harvest was made in September, they can be classified into early maturation group. Male sterile female lines were the following: SL 1, SL 2, SL 3, SL 4, SL 5. The maintainer male lines were: CL 1, CL 2, CL 3, CL 4, CL 5. In Hungary, there are only a few male sterile femalelines, so we will use these lines for hybrid production during the next years.

Treatment of Grape Juice by Osmotic Evaporation

ABSTRACT: Osmotic evaporation (OE) was applied to grape juice to increase the sugar content and thus to improve the quality of wine obtained after fermentation. The use of aqueous solutions of glycerol as extractant avoids corrosion and scaling, which are the main problems in OE with brines. Preliminary experiments were performed on lab scale using water or glucose solutions as feed, and NaCl or glycerol as extractant. The runs with NaCl allowed measurement of the membrane transport properties, whereas glycerol was used to quantify the concentration polarization phenomena involved. The extract side concentration polarization severely limited the flux achievable for glycerol concentration above 50% wt, while the extract side concentration was negligible in the OE with NaCl. The feed side concentration polarization played a minor role for glucose content up to 40% wt. Experiments with grape juice were performed on pilot scale equipped with plate and frame modules. The performance were in good agreement with lab results on glucose model solutions, the lower flux observed was due only to the low temperature of operation. The process was tested on 3 types of grape juice (white, rosé, and red). Treated and control juices were fermented, and corresponding wines were analyzed for selected parameters and evaluated by sensory analysis. The OE treatment removed water from grape juice and increased both the total soluble solids and sugar content of juice, thus ethanol content and dry extract in wine always increased. The osmotic evaporation significantly improved sensory quality of red wine that was judged as having a full body, more structure, and persistence.

Long-term ozone exposure and ozone uptake of grapevines in open-top chambers

Ozone uptake of pot-grown grapevines, fruit yield and sugar concentrations in juice were studied over the course of 4 years. In three of the study years, plants were exposed to contrasting ozone levels in open-top chambers. Results showed that juice quality was more sensitive to ozone exposure than grape yield. Ozone-induced reductions in grape yield were best described by the level of ozone exposure in the 2 years prior to harvest, whereas sugar content of juice was mainly affected by current and previous year ozone exposure. Regression models were developed to facilitate quantitative assessments of the effects of ozone on yield and quality. The observed effects on grape yield and on carbohydrate accumulation in fruit were slightly better explained when a threshold of 6 nmol m −2 s −1 was applied to cumulative uptake of ozone (CUO6) compared with AOT40 exposure or other CUO thresholds. Curvilinear regression models were developed which explained up to 75% of variance of the datasets. These models indicate a critical level of 1.1 mmol m −2 ozone (CUO6 from June to September) to protect carbohydrate accumulation in fruit with ozone taken up by the plants over consecutive years. For grape yield the CUO6 threshold was 2.2 mmol m −2 ozone. Exceedance of this threshold would be expected to reduce grape yield and sugar translocation to fruit by 10% with substantial degree of uncertainty (95% confidence interval 1–19%). For individual years, the critical level could be increased to 2.3 mmol m −2 for carbohydrate accumulation and 3.5 mmol m −2 CUO6 for grape yield if the CUO6 of 0 in the subsequent year was not exceeded.

Effect of fertilizer mechanism and harvest time on juice volume, sugar brix and bioethanol in three varieties of sweet sorghum (Sorghum bicolor)

An experiment was conducted during the rainy season of 20142015 at Experimental Garden of Indonesian Research Cereals Institute, Gowa, Indonesia to evaluate the effect of fertilizer nutrient release mechanism and harvest time on volume and sugar content of juice and bioethanol yield of 3 varieties of sweet sorghum (Sorghum bicolor (L.) Moench). The experiment was performed in the field using split-split plots design, where the main plot received mechanism of fertilizer that consisted; fast release (P ), slow release (P ) and combination of both fast re- 1 2 lease and slow release (P ), while the sub-plots received harvest time treatments, viz. Harvesting before physi- 3 ological maturity (W ), Harvesting at the exact physiological maturity (W ) and Harvesting after physiological matu- 1 2 rity (W ), and in the sub-sub-plots 3 varieties viz. Numbu (V ), Super 1 (V ) and Super 2 (V ). The results 3 1 2 3 showed that fertilization with P gave the best average results of juice volume and others parameters compared to 3 P . P fertilization gave the best results of sugar content, while P gave the best results of bioethanol produciton. 1 2 3 W gave the best results of volume of juice, while W and W gave the best results of sugar content. W and W re- 1 3 2 1 3 corded the best results on bioethanol. V varieties recorded the highest volume of juice. 2

Near-Infrared Monitoring of the Growth Period of Japanese Pear Fruit Based on Constituent Sugar Concentrations

To develop nondestructive monitoring techniques in plant science, near-infrared spectroscopy (near-IRS) was applied to estimate the growth stages of the fruit of the Japanese pear tree based on the constituent sugar concentrations in the juice. Regular differences were observed among the spectra of juice from pears of different maturity, and the absorption bands of these spectra were assigned to carbohydrate. The multiple linear regression calibration equations of each constituent sugar (namely, sucrose, glucose, fructose, and sorbitol) used three to seven wavelengths as independent variables. The correlation coefficients of each sugar concentration were 0.97, 0.90, 0.99, and 0.98, with standard error of prediction values of 0.17, 0.15, 0.21, and 0.40 respectively. Results of measurement of each constituent sugar concentration in Japanese pear juice by near-IRS indicated that the sugar components changed with the growth period of fruits. Therefore, near-IRS can be used to effectively evaluate the growth s...

Analysis of the sugar content of fruit juices and drinks using ultrasonic velocity measurements

SummaryThe use of ultrasound to determine the sugar content of fruit juices and drinks has been assessed. The velocity of ultrasound and the density were measured in solutions of D‐glucose, D‐fructose, and sucrose at various concentrations (0–40% w/v) and temperatures (10–30°C). The velocity of ultrasound was measured in 50:50wt:wt mixed solutions of sucrose and D‐glucose over the same range of concentrations and temperatures. Measurements of the velocity of ultrasound, the density and the refractive index were made on various fruit juices and drinks at 20°C. The sugar content of the juices and drinks was determined by enzymatic assay. Ultrasonic measurements are shown to predict sugar contents in pure sugar solutions to within 0.2% w/v and in mixed sugar solutions to within 0.5% w/v. The ultrasonic measurements were sensitive to sugar species. It is shown that ultrasound compares well with other techniques for sugar content determination in fruit juices and drinks, and has the advantage that the equipment can be used for on‐line process control. Applications for this ultrasonic technique are proposed.

The Production of Resveratrol (3,5,4'-trihydroxystilbene) by Grape Berries in Different Developmental Stages

Resveratrol ( trans -3,5,49-trihydroxystilbene), a grapevine phytoalexin related to grey mold resistance, is produced by grape berries of Vitis vinifera L. and Vitis labrusca L. in response to UV-irradiation; its production decreases during fruit ripening. In vinifera varieties, the resveratrol content of whole berries steadily declined between the green stage and complete maturity, nearing zero in ripe fruit, while a pronounced decrease was observed in the berries of V. labrusca after veraison. On the other hand, resveratrol synthesis was found to be located in the skin, thus showing that the principal resistance of grapes to fungal attacks takes place at this level. Finally, the decrease of resveratrol production during maturation was also confirmed by the fact that there is a clear negative correlation between the resveratrol content of grape skin and the developmental stage of berries measured by the sugar concentration of juice.

Application for Near Infrared Spectroscopy for Predicting the Sugar Content of Fruit Juices

ABSTRACTNear infrared spectroscopy, operated in the transmission mode, was used to predict the total sugar content of a variety of fruit juices. Attempts were made to determine individual sugars in some of the juices. The best results were obtained for total sugar determination when separate calibrations were used for each type of juice. For orange juice, when n=35, r=0.87, the standard error of calibration = 0.22, and the bias and standard error of prediction = 0.04 and 0.25 respectively. Minimal amount of sample preparation was required for the rapid and nondestructive analysis of the total sugar content of juices. The potential application and limitations of the method are discussed.

Use of refractometer to determine soluble solids of astringent fruits of Japanese persimmon (Diospyros kakiL.)

SummaryA method was developed to determine soluble solids refractometrically in astringent Japanese persimmon fruits with a high soluble tannin content. Adding 5% PEG # 6000 to the fruit juice in equal amount followed by centrifugation or filtration removed interfering tannins effectively from the mixture by forming precipitates. The refractometer readings were taken with the resultant solution and 2.5% PEG # 6000 and then the refractometer sugar value of the original juice was calculated by multiplying by two the difference of the two readings. The calculated value approximated closely to the total sugar content of juice.

Crop Load and Efficiency for Light Utilization in the Grape Caused by Different Training

An ecological investigation of the relation between crop load and some cultural conditions was made for the grapes“Kyoho” (Vitis labruscana Bailey × Vitis vinifera L.) and“Campbell Eary” (Vitis labruscana Bailey) .(1) Correlation coefficients (γ) between crop load and the sugar content in juice from the fruit, the percentage of dry matter in the fruit and the total dry matter production were -0.821, -0.734 and +0.875, respectively.(2) For“Kyoho, ”a leaf area of approximately 1200 m2 was necessary to produce 1000 kg of fruit (17°Brix) in cultivation by the horizontal overhead training system. The data of the total dry matter production and the dry weight of the fruit, indicate that 42% or more of the total leaf area in the orchard contributes to the production of fruit.(3) “Kyoho”grown in Ohbu city during the second half of August took about 5 days to increase 1° Brix, but this tendency to increase leveled off in September.(4) “Kyoho”cultivated by the horizontal overhead training system in Ohbu city had a small crop load, and the gross sugar production for the total area of the orchard was low. However, fruits of excellent quality were produced at a relatively early stage.“Kyoho”cultivated by a modified Munson training system in Mizunami city had an excessive crop load, and the leaf area index was extremely small. As the result, the gross sugar production of the total fruit was large. However, the maturing stage was delayed, and some trees died. An orchard of“Campbell Early”cultivated by a modified Kniffin training system in Aomori had a moderate crop load. In spite of this, there was a large leaf area index and the gross production of sugar was high.(5) The distribution of light intensity in the orchards and the light-photosynthesis curve for the grape leaves showed that the efficiency for light utilization was very high in the orchard with the modified Kniffin training system, but was low in the horizontal overhead training system.

Influence of Temperature on the Storage of Satsuma Orange

Mature Satsuma oranges (Citrus unshiu Marc.) were harvested on November 27, 1968 and were stored at various temperatures and 80-90% R. H. Decaying condition and respiration of fruits, changes in sugar, acid and ascorbic acid concent of juices, were studied during and after storage.1. At 20°C, the decay by stem-end rot increased rapidly after 60 days of storage, and marked shriveling appeared on the peels of fruits. Although the fruits stored at 10°C maintained its keeping qualities for a longer period (120 days), eventually the shriveling and stem-end rot occurred. At lower temperatures, 2°C and 5°C, the decay by penicillum mold increased rapidly after 120 and 160 days of storage, respectively. The shriveling of peel could not observed in the fruits at the both temperatures. The fruit at 2°C, however, showed symptom of chilling injury from the middle of April, and objectionable graying developed on the peel.At 2°C, a pronounced decrease in respiration occurred soon after the beginning of storage, and the low respiration level remained constant until the increasing time of decay, when a slight increase in respiration took place. The same pattern of respiration was observed in the other cases.In below 6°C, ascorbic acid and sugar concentration of juice, which extracted from fruit, remained approximately the same as in the fruit before storage, but total acids concentration and sugar concentration decreased remarkably even in undecayed fruit at the end of storage period as compared with those of fruit stored low temperature.At 2°C, evolution of volatile substances from the fruits increased pronouncedly with the development of chilling injury, and those fruits were always accompanied with the rise of respiration.2. CO2 production of fruits transferred from 2°, 6° and 10°C increased for the first 8-12 hours after transfer to 20°C and then decreased, and it was evident that there was a cumulative time-temperature influence of chilling exposure upon the degree of stimulation in CO2 evolution.The low temperature during storage resulted in the notable decrease of chemical compositions in fruit juices after transfer to 20°C.Naturalization, in which the temperature of fruits rised gradually, prevented the rapid rise of respiration. And also, number of decayed fruits and decrease of chemical compositions of fruits in this treatment were more less than those of fruits transferred directly to 20°C.

Título en español.

(1) La substancia responsable de las discrepancias encontradas en la determinación de azúcares reductoras y azúcares totales por el método de Lane-Eynon es el ácido ascórbico. Si se corrige para el ácido ascórbico, usando el factor 0.686, la discrepancia desaparece y el método de Lane- Eynon es aplicable. (2) Para conseguir el contenido de azúcares en el jugo de acerola, lo único que hay que determinar son los azúcares reductores corregidos, ya que se ha probado experimental y estadísticamente que no hay ninguna diferencia significativa entre azúcares reductores corregidos y azúcares totales corregidos. (3) El contenido de azúcares en el jugo de acerola almacenado a 45°F y a temperatura de salón no varía después de 1 año. (4) Cuando el jugo de acerola se almacena a 45°F la cantidad del ácido ascórbico disminuye con menos prontitud que cuando se almacena a temperatura de salón. Sin embargo la temperatura no afecta significativamente el contenido de azúcares en el jugo.

Studies on the sugar concentration of the juice in the stalk of sugar sorghum (Sorghum vulgare PERS. var. saccharatum BOERL).

The following experiments were made at Tokyo University Farm in 1948 and 1949. For the experimentation one variety of Japanese species was used. Sugar concentration of the juice was estimated by the sugar hand-refractometer, and for crushing the stalks the small compressor of vermicelli was used. EXPERIMENT I : (See Fig. I) Change in the Sugar Concentration of the Juice in the Stalks of Sugar Sorghum after the Heading Time. The best time for cutting and crushing the stalks of sugar sorghum has not been clearly known. It has been differently said either to be in the milk-ripe stage, or in the dead-ripe stage, or in the middle of the two. Experiment No. I. was carried out in order to know clearly about the harvesting time. The result follows : The sugar concentration was the highest from the fifth week to the tenth week after the heading, in other words, between the red-ripe stage (which corresponds to the yellow-ripe stage of wheat) and the dead-ripe stage. The concentration was not so high either in earlier or later period than that. In the earlier period the concentration was low, and in the later period there was a change in the quality of the juice. On the other hand, the amount of the deprived juice was almost same from the heading time to the matured time. The percentage of the weight of the deprived juice to that of the raw stalk was 65∼75% on the average. It is rare in the plant world that the amount of the juice does not decrease long time after the plant was decayed. Therefore, in deciding the time for cutting sugar sorghum, it is not necessary for us to be worried about the amount of juice to be obtained. After all, the cutting time is any day between the fifth and tenth week after the heading. EXPERIMENT II : (See Fig. II) The Effect of the Seeding time on the Concentration of Juice. In 1948 the writer found that there was a difference in the concentration of juice according to the heading time. (Of course, all plants were sown at the same time) The concentration of juice was higher in those that headed later than these that headed earlier, but the latter grew better than the former. Accordingly, in 1949 in order to put off the heading time without impairing the growth of the plant, the seeds were sown as late as possible. The writer compared the concentration of juice of those that were sown late to head later with that of those that were sown early to head earlier. He found the concentration of juice in the former was higher than the later, so long as there was no difference between the two in growth and that there was no difference between the two groups of the plants concerning the amount of juice contained in a plant. EXPERIMEMT III : (See Fig. III) The Effect of the Sowing Density upon the Sugar Concentration of Juice. This experiment was done in order to learn the difference of the concentration of juice between the stalks planted thinly and those planted thickly. The sugar concentration was higher in the latter than in the former group. In this experiment again the difference in the amount of juice obtained from a plant was so little that it could be ignored entirely. Nor were these differences between the amount of the Juice obtained from sugar sorghum of the said two groups per one tan (about one-forth acre).