Non-destructive tests on the prediction of apple fruit flesh firmness and soluble solids content on tree and in shelf life

The aim of this study is to investigate the effect of sunburn injury on fruit quality parameters (colour-coverage, depth of affected tissue, fruit flesh firmness, soluble solids content) of apple.The symptoms of sunburn injury appeared in concentric ring shape, differed from each other and surface colour-coverage. This can be due to the ratio of the injury. The authors observed the following colours on the fruit surface (from the epicentre of the blotch on the transversal diameter of the fruit) dark brown (strongly affected), light brown (moderately affected), pale red transition (poorly affected), red surface colour-coverage (not affected).Sunburn of apple fruits is a surface injury caused by solar radiation, heat and low air relative humidity that in the initial phase results in a light corky layer, golden or bronze discolouration, and injuries to the epidermal tissue, in the surface exposed to radiation. Thus it detracts from its appearance, but in most cases, it would not cause serious damage to the epidermal tissue. The depth of affected tissue is not considerable, its values are between 1.5-2.0 mm generally. It is commonly known that the tissue structure of apple fruit is not homogeneous. Accordingly, the degree of injury shows some differences under the different parts of the fruit surface.On the basis of flesh firmness research, the authors established that the measure of flesh firmness of the affected part of apple fruit increases with the effect of sunburn. The consequence of this is the suffered plant cells will die, the water content of this tissue decreases and the fruit gets harder. This water-loss caused the increase of soluble solids content.

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Modelling Soluble Solids Content Accumulation in ‘Braeburn’ Apples

Plants ◽

10.3390/plants10020302 ◽

2021 ◽

Vol 10 (2) ◽

pp. 302

Author(s):

Konni Biegert ◽

Daniel Stöckeler ◽

Roy J. McCormick ◽

Peter Braun

Keyword(s):

Explanatory Power ◽

Partial Least Square ◽

Optical Measurements ◽

Soluble Solids ◽

Sensor Data ◽

Soluble Solids Content ◽

Mixed Effect ◽

Laboratory Errors ◽

Solids Content ◽

Non Destructive

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.

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The Quality of Superior Seedless Bunches during Shelf Life as Determined by Growth on Different Rootstocks

Agriculture ◽

10.3390/agriculture11100990 ◽

2021 ◽

Vol 11 (10) ◽

pp. 990

Author(s):

A. A. Lo’ay ◽

Hamed Ismail ◽

Hazem S. Kassem

Keyword(s):

Shelf Life ◽

Soluble Solids ◽

Ion Leakage ◽

Soluble Solids Content ◽

Close Attention ◽

Oxidative Reactions ◽

Seedless Grape ◽

Metabolism Enzyme ◽

Solids Content

Vineyard rootstocks are an important tool in the local and international market for growing the Superior Seedless grape cultivar, which is highly favored by customers. As a result, it is vital to pay close attention to the quality of clusters during handling. The current study aimed to determine whether Superior Seedless vines can be grown on specific rootstocks, resulting in higher quality during shelf life. Vines of the Superior Seedless vine cultivar that were used were 13 years old and had been grown on sandy soil. These vines were grafted onto four different rootstocks (genotypes), namely Freedom, 1103 Paulsen, SO4, and Own Root. The soluble solids content (SSC%) was selected as 16%. Bunches were subsequently stored in the lab at 27 ± 1 °C with 57 ± 3% air relative humidity for three days. Rootstock 1103 Paulsen’s quality was found to be superior to that of the other rootstocks, according to the results of the study. Rootstock 1103 Paulsen maintained its ascorbic acid (AA) content, which is reflected in its antioxidant capacity, according to the results. In addition, lipid peroxidation accumulation and ion leakage percentages indicated that oxidative reactions were at their lowest levels. The results show that 1103 Paulsen decreases cellular metabolism enzyme activities at the shelf life level and improves the bunch quality of Superior Seedless (scion) grapes within 4 days of application. As a whole, the results show that the 1103 Paulsen rootstock produces Superior Seedless bunches of a high quality that is preserved throughout the shelf life period.

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Effect of Some Citrus Essential Oils on Post-Harvest Shelf Life and Physicochemical Quality of Strawberries during Cold Storage

Agronomy ◽

10.3390/agronomy10101466 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1466

Author(s):

Said A. Shehata ◽

Emad A. Abdeldaym ◽

Marwa R. Ali ◽

Reda M. Mohamed ◽

Rwotonen I. Bob ◽

...

Keyword(s):

Weight Loss ◽

Essential Oils ◽

Shelf Life ◽

Polyphenol Oxidase ◽

Oxidase Activity ◽

Soluble Solids ◽

Soluble Solids Content ◽

Polyphenol Oxidase Activity ◽

Total Antioxidant ◽

Solids Content

Utilization of essential oils alone or incorporation with edible films is an appropriate technique to conserve the quality attributes and reduce post-harvest deterioration in fresh vegetables and fruits. Strawberries, being perishable fruits have a short shelf life, and using essential oils is considered one of the most suitable methods to prolong their shelf life during storage. The current study assessed the impact of different essential oils, including lemon oil (L), orange oil (O) and mandarin oil (M) on the physicochemical and microbial load of strawberries (Fragaria × ananassa cv. Festival) stored at 2 ± 1 °C and 95% relative humidity (RH) for 18 days. The differences in the physicochemical and microbial properties of strawberries were assessed by determining the following parameter changes: weight loss, decay percentage, firmness, soluble solids content, titratable acidity, color, anthocyanins, vitamin C, total phenol, total antioxidant, catalase activity, polyphenol oxidase activity, sensory evaluation, microbial content, total coliforms, molds, and yeasts. The results of this study indicated that the fruits treated with all essential oils treatments (L, O and M) had higher total antioxidant content and physicochemical properties than untreated fruits, due to protection against the microbial growth of molds, and yeasts. At the end of the storage period, the treated fruits showed a greater acceptance and sensory attributes than the untreated fruits. Furthermore, the correlation study showed a significant and negative relationship between the total antioxidant of treated fruits and following quality attributes including, weight loss, decay percentage, respiration rate soluble solids content, polyphenol oxidase activity, molds, and yeasts. It is noteworthy that all the essential oil treatments extended the shelf-life of strawberries and delayed their deterioration up to 18 days.

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