Assessment of Microwave Permittivity for Detecting Fruit Maturity

1994 ◽  
Vol 347 ◽  
Author(s):  
Stuart O. Nelson ◽  
W. Roy Forbus ◽  
Kurt C. Lawrence

ABSTRACTPermittivity measurements from 0.2 to 20 GHz were taken on fresh peaches of three varieties at three stages of maturity during the growing season to determine whether dielectric properties might be correlated with maturity. Other physical properties of the peach tissue, such as density, moisture content, firmness, and total soluble solids content, were also determined. Two indices, based on dielectric constant and loss factor values at 0.2 and 10 GHz were found to correlate with stage of maturity, but they were dependent on the variety, and further study is necessary to determine their practical usefulness.

HortScience ◽  
2000 ◽  
Vol 35 (4) ◽  
pp. 550C-550b
Author(s):  
Melissa Neal ◽  
Ellen B. Peffley

Over the past several growing seasons researchers at Texas Tech University have observed that certain onions appeal to rabbits more than other onions, meaning that rabbits tend to nibble on certain lines or varieties and leave other lines undisturbed. We were interested in determining the cahracteristics of the onions that rabbits seemed to like. Onions were planted at random in the TTU breeding nursery. During the growing season all onions were rated for rabbit appeal - those with chewed leaves and or bulbs were recorded as liked by the rabbits. All onions in each plot, whether disturbed or undisturbed by the rabbits, were tested for pyruvate concentration and soluble solids content after harvest. Pyruvates were measured by mmol/gram pyruvic acid and soluble solids content by °Brix refractometer reading. The most damage occurred in onion lines that had the lowest pyruvate levels. Soluble solids did not appear to affect the rabbits' nibbling.


2003 ◽  
Vol 25 (1) ◽  
pp. 59-62 ◽  
Author(s):  
Cassandro Vidal Talamini do Amarante ◽  
Clarice Aparecida Megguer ◽  
Luiz Eduardo Bassay Blum

Apple trees, cultivars Gala and Fuji, were sprayed at full bloom with thidiazuron (TDZ) at the doses of 0, 5, 10, or 20 g (a.i.) ha-1 and fruit were assessed for quality and maturity. In both cultivars, the increase of TDZ dose had detrimental effects on fruit quality, causing a reduction of fruit red surface and an increase of percentage of fruit that was asymmetrical and with calyx-end rot. TDZ caused an increment of calyx-end aperture that might have increased calyx-end rot. TDZ increased density and the length : diameter (L : D) ratio of the fruit. The number of viable seeds was not affected by TDZ. TDZ resulted in a substantial delay of fruit maturity in 'Gala' but not in 'Fuji'. TDZ also reduced soluble solids content (SSC) in 'Gala' and reduced titratable acidity in both cultivars.


OENO One ◽  
2000 ◽  
Vol 34 (2) ◽  
pp. 57 ◽  
Author(s):  
Aziz Ezzahouani

<p style="text-align: justify;">A study was conducted to determine the effects of post-bloom applications of forchlorfenuron (CPPU) at 5 and 10 ppm, and the practice of cane girdling on fruit quality of two table grape cultivars (cvs.) « Perlette » (seedless) and « Italia » (seeded). For « Perlette » cv, CPPU treatments increased significantly berry weight and crop per vine, relatively to the control. However, soluble solids decreased while the acidity increased, reflecting a late maturation of berries from the treated vines. The delay of fruit maturity was also observed in « Italia » grapes, measured by a significant decrease in fruit soluble solids content. Girdling had a slight and non significant effect on fruit quality for both cvs.</p>


2009 ◽  
Vol 70 (1) ◽  
pp. 135-144 ◽  
Author(s):  
Marek Gajewski ◽  
Zenon Węglarz ◽  
Anna Sereda ◽  
Marta Bajer ◽  
Agnieszka Kuczkowska ◽  
...  

Quality of Carrots Grown for Processing as Affected by Nitrogen Fertilization and Harvest TermIn 2007-2008 the effect of nitrogen fertilization and harvest term on quality of two carrot cultivars was investigated. The field experiment was carried out in Żelazna Experimental Station of Warsaw University of Life Sciences. Karotan F1and Trafford F1cultivars, commonly grown for juice industry, were the objects of the experiment. Carrot seeds were sown at the beginning of May. Nitrogen fertilization was applied in five rates, ranged from 0 to 120 kg·ha-1and in two terms — before sowing and in the middle of growing season. Roots were harvested in three terms: mid-September, mid-October and the first decade of November. After harvest there were determined: nitrates (NO3) content in carrot roots and juice, soluble solids, colour parameters of juice in CIE L*a*b*system. The dose and the term of nitrogen fertilization influenced nitrates content in carrots, and the highest NO3concentration was found in carrots fertilized with 120 kg·ha-1of N before sowing. Karotan showed higher nitrates accumulation than Trafford. The content of nitrates in the roots was markedly higher than in carrot juice. Nitrates content in carrots decreased with delaying of harvest time, in opposite to soluble solids content. Soluble solids content and colour parameters of carrot juice were not affected by nitrogen fertilization, but the lowest L*, a*and b*values were observed at the last term of harvest.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 520e-520
Author(s):  
Juan E Manzano ◽  
Oswaldo Valor

Mango fruits `Criollo de Bocado' harvested at the mature-green stage were treated with a hydrothermic treatment of 55 °C for 3 min and stored for 20 days at temperatures of 10 ± 2, 15 ± 2 and 28 ± 2 °C. A randomized design 2 × 3 × 4 with three replications was used. Some chemical parameters were analyzed, such as total soluble solids content (% TSS), pH, tritatable acidity, and TSS/tritatable acidity ratio. TSS content increased with storage time at low temperature. The pH increased measurably with storage temperature, while tritatable acidity values results had inconsistent data.


2019 ◽  
Vol 12 ◽  
pp. 01018
Author(s):  
V.B. Costa ◽  
S.B. de Andrade ◽  
P.L.P.K. Lemos ◽  
A. Bender ◽  
C. Goulart ◽  
...  

The Campanha Gaucha region, southern Brazil, has received significant investments in Viticulture during the last decades, especially for the production of quality wines. However, implementing the production of American and hybrid grapes in this region constitutes and opportunity to supply the increasing demand of the grape juice market in Brazil. Juices of two varieties, “Bordô” and “Concord”, from two locations, Dom Pedrito and Santana do Livramento, were analysed in terms of the following physico-chemical aspects: total city, volatile acidity, density, pH, soluble solids content, color intensity, and hue. “Bordô” juices presented higher total acidity and did not differ in relation to location. Higher volatile acidity was found in “Concord” juice from Santana do Livramento. Higher pH was found in the variety “Concord” and in the location Dom Pedrito. For this same location, the “Concord” grape juices showed higher soluble solids values. Color intensity was higher in Santana do Livramento. Color hue was higher in Dom Pedrito. Both variety and location impacted significantly on physico-chemical aspects of grape juices, although all the grapes were produced within the Campanha Gaucha region.


Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 302
Author(s):  
Konni Biegert ◽  
Daniel Stöckeler ◽  
Roy J. McCormick ◽  
Peter Braun

Optical sensor data can be used to determine changes in anthocyanins, chlorophyll and soluble solids content (SSC) in apple production. In this study, visible and near-infrared spectra (729 to 975 nm) were transformed to SSC values by advanced multivariate calibration models i.e., partial least square regression (PLSR) in order to test the substitution of destructive chemical analyses through non-destructive optical measurements. Spectral field scans were carried out from 2016 to 2018 on marked ‘Braeburn’ apples in Southwest Germany. The study combines an in-depth statistical analyses of longitudinal SSC values with horticultural knowledge to set guidelines for further applied use of SSC predictions in the orchard to gain insights into apple carbohydrate physiology. The PLSR models were investigated with respect to sample size, seasonal variation, laboratory errors and the explanatory power of PLSR models when applied to independent samples. As a result of Monte Carlo simulations, PLSR modelled SSC only depended to a minor extent on the absolute number and accuracy of the wet chemistry laboratory calibration measurements. The comparison between non-destructive SSC determinations in the orchard with standard destructive lab testing at harvest on an independent sample showed mean differences of 0.5% SSC over all study years. SSC modelling with longitudinal linear mixed-effect models linked high crop loads to lower SSC values at harvest and higher SSC values for fruit from the top part of a tree.


2017 ◽  
Vol 45 (1) ◽  
pp. 120-125 ◽  
Author(s):  
Ersin ATAY ◽  
Seckin GARGIN ◽  
Ahmet ESITKEN ◽  
N. Pinar GUZEL ◽  
A. Nilgun ATAY ◽  
...  

Orchard performance is influenced by weed competition. In this study, the effects of weed competition on nutrient contents, chemical and physical fruit quality properties were sought. The study was carried out in a high-density apple orchard (‘Golden Delicious’/M.9) over two consecutive growing seasons. The effect of weed competition was studied at three different levels: weak, moderate and strong. Fruit firmness, soluble solids content, macronutrients (such as nitrogen, potassium and calcium) and potassium+magnesium/calcium ratio in fruit were significantly affected by weed competition. Strong weed competition negatively affected soluble solids content and potassium+magnesium/calcium ratio. In both trial years, soluble solids content was significantly higher in weak weed competition. In the first year of the study, soluble solids content ranged between 13.77±0.06% (strong weed competition) and 15.20±0.10% (weak weed competition). In the following year, soluble solids content values were determined as 13.13±0.23% in strong weed competition and 13.83±0.21% in weak weed competition. Weak weed competition showed superiority for fruit weight and potassium+magnesium/calcium ratio. As a whole, this study indicates that insufficient weed control in tree rows might be a limiting factor for fruit quality in high-density apple orchards.


1991 ◽  
Vol 71 (1) ◽  
pp. 231-234 ◽  
Author(s):  
M. Meheriuk ◽  
G. H. Neilsen ◽  
D.-L. McKenzie

Calcium chloride (CaCl2) and Ca(OH)2 sprays reduced rain splitting in Van cherries (Prunus avium L.). Multiple applications were better than single sprays. Soluble solids content was increased in many instances by the treatments. Fruit shrivel was appreciable in cherries sprayed with Ca(OH)2 particularly in hot seasons. Single or multiple applications of Nutri-Save (a polymeric coating), Pro-Stick (a sticking agent) and Envy (an antitranspirant) did not affect rain splitting in Stella cherries. Key words: Prunus avium L., calcium sprays, fruit shrivel, cherry


Sign in / Sign up

Export Citation Format

Share Document