South African Journal of Enology and Viticulture

Selenium (Se) deficiency in humans could be improved by biofortification of food with selenium, 1-Methylcyclopropene (1-MCP) treatment is beneficial for the non-sulfur storage of fresh fruit. This study investigated fruit quality of table grape (Hutai No.8) with foliar Se fertilizer at maturity, and fruit quality changes of table grape during shelf life stages that caused by postharvest 1-MCP treatment in 2016 and 2017. The results showed that foliar Se fertilizer application significantly increased Se content in grape berries at maturity, and the raised rate were 43.09% and 33.24% compared to that of control in 2016 and 2017 respectively, meanwhile it increased the nutritional components in grape berries, including soluble proteins, soluble sugars, Vitamin C, total soluble solids, proanthocyanidin content and so on, and decreased the titratable acidity content. During shelf life stages, 1-MCP application decreased the decay number of grapes, and SE + 1-MCP treatment had the most excellent fruit quality among all treatments in two consecutive vintages. In conclusion, Se fertilizer application could increase Se content in grape berries, also improved the fruit nutritional and health care values at maturity. 1-MCP application could delay the process of ripening and senescence for Se-enriched grape and maintaining the postharvest quality of table grape during shelf life stages, it allows us to market the fruit at a more advanced ripening stage without quality loss.

Ozonated water has recently been incorporated in the management of grapevine diseases, which in turn can alter the fruit quality. When wood-inhabiting pathogens are involved, trunk injection or “endotherapy” represents a promising application method. Thus, the present study aimed to evaluate the effect on grape quality of ozonated water applied to Vitis vinifera L. cv. Bobal grapevines through endotherapy (E) or its combination with spraying (E + S). Grape quality at harvest was evaluated through several enological and chromatic parameters, the phenolic maturity, the varietal aroma potential index (IPAv) and the phenolic and volatile composition. The E treatment improved the chromatic characteristics and favored the accumulation of phenolic compounds. Conversely, E + S had a detrimental effect on the color and phenolic content and, although their synthesis was enhanced, the extractability of anthocyanins was negatively affected. In terms of aroma, both treatments reduced the content of glycosylated precursors but increased certain free volatiles. The application of ozonated water to grapevines, even when injected into the trunk, results in changes in fruit quality and a possible impact on wine attributes. Our findings and those in the literature support that, with the appropriate dose, frequency and method of application, ozonated water could be used with a twofold objective: disease management and grape quality improvement.

‘Ganlv 1’ is a new cultivar of Actinidia eriantha selected from the wild natural population, which has the advantages of moderate taste, high yield, easy peeling and high ascorbic acid (AsA) content. In this study, ‘Ganlv 1’ was used to explore the changes in fruit quality, soluble sugar components, sucrose metabolism-related enzymes activities and sucrose metabolism-related enzyme genes’ expression during the fruit’s development. The results showed that, except for AsA, the changes in the fruit quality index and fruit growth and development during the development of ‘Ganlv 1’ basically exhibited the same trend. The fruit shape index was different in the different development stages of the fruit, and tended to be stable with fruit growth and development. The dynamic changes of the dry matter content indicated that the best time for fruit harvest was about 160 days after full bloom. The main sugar components in the fruit were fructose, glucose and sucrose, and sucrose and glucose were the main sugars in the soft-ripening stage. The trend of sucrose accumulation, the activities of the sucrose metabolism-related enzymes and the expression of the sucrose metabolism-related genes indicated that 130–145 days after full bloom (DAFB) might be the critical period of sucrose metabolism. The results are of great significance for clarifying the developmental characteristics and dynamic changes in the sugar components in A. eriantha fruits, and lay a foundation for further studying of the mechanism of sugar metabolism in A. eriantha.

The wine grape ‘Cabernet Sauvignon’ was selected as test material, the effect of 50 mmol·L−1 NaCl and 50 mmol·L−1 NaHCO3 spraying grape fruit on grape quality was investigated, the influence of proper neutral salt and alkali salt on fruit ripening and quality formation were studied. In order to provide reference basis for further study on the changes of grape fruit quality under saline-alkali condition. The results showed that both of the treatment had no significant effect on grape weight. But compared to the control, the TSS content decreased under the treatments and the TSS content was significantly lower in NaHCO3 stress than NaCl. Moreover, both of treatment delayed the accumulation of anthocyanins and the degree was higher in NaCl stress than NaHCO3. On the contrary, the accumulation of total acid and the content of tartaric acid and malic acid were promoted in treatments compared with control in fruit ripening (after flowering 109 days). Futherly, quantitative real-time PCR analysis showed that saline and alkaline treatment all inhibited the expression of MYBA1 and UFGT genes, which played an important role in anthocyanin synthesis and the result was consistent with the accumulation of anthocyanins, suggesting that the accumulation of anthocyanins was delayed under saline and alkaline stress due to inhibiting the expression of key genes. Therefore, the salt-alkaline treatment of the fruit was not beneficial to the improvement of fruit quality and the fruit ripening process was delayed as well.

Irrigation with moderate salinity stress in a hydroponic system improves the inner and outer fruit quality of tomato (Solanum lycopersicon Mill. ‘House Momotaro’). We investigated the effects of 50 mM NaCl in a hydroponic solution on the levels of various metabolites, including soluble sugars, amino acids, and organic acids, and on the expression levels of salinity-responsive genes during fruit development. Under salinity, Brix (%), surface color density, and flesh firmness of the fruit were significantly enhanced, whereas fruit enlargement was suppressed. Salinity stress strongly promoted the accumulation of sucrose, citrate, malate, and glutamate, and slightly promoted glucose and γ-amino butyric acid in red fruit. At the transcriptional level, up-regulation of ethylene-synthetic 1-aminocyclopropane-1-carboxylate oxidase and down-regulation of photosynthetic chlorophyll a/b binding protein Cab-1B occurred earlier in stressed fruit than in control fruit. Additionally, the carotenoid-biosynthesis regulatory gene, Phytoene synthase 1, and phosphoenolpyruvate carboxykinase (PEPCK) were up-regulated under moderate salinity in the red stage. The expression profiles of these genes in stress-treated fruit were consistent with the changes in fruit quality, including earlier ripening and a deeper red color. Furthermore, the up-regulation of PEPCK suggested that gluconeogenesis is involved in the accumulation of sugars in salinity-stressed fruit.

본 시험은 가을철 기온이 높게 유지되는 대구지역에서 성숙기 동안 '후지'의 과실품질 변화와 수확시기별 과실품질과 저장성을 3년(2007년, 2009년, 2010년) 조사하였다. 성숙기 동안 과실품질의 변화는 만개 후 120-135일부터 만개 후 183-198일까지 조사하였다. 수확시기별 과실품질과 저장성 비교는 만개 후 180일 이후에 수확한 과실들을 대상으로 하였다. 과실 성숙기 동안 대구지역 '후지'의 문제점은 <TEX>$20^{\circ}C$</TEX>의 높은 기온에 따른 착색불량이었다. 수확시기별 과실품질 비교에 있어, 수확시기가 연장될수록 가용성 고형물 함량과 착색은 높아졌다. 수확 시의 과중은 수확시기에 영향을 받지 않았고, 수확 시의 경도와 산 함량은 동결피해가 발생했을 때 심하게 감소되었다. 저온저장 20주 동안의 에틸렌 발생량 및 경도, 산 함량은 수확시기에 따른 차이가 없었다. 2009년 만개 후 216일에 수확한 과실들의 저온저장 중의 가용성 고형물 함량은 수확시의 가용성 고형물 함량과 비교해 비슷하였으나, 2009년 만개 후 201일에 수확한 과실들은 수확시보다 높아졌다. 그러나 동결피해를 받은 후 수확한 과실의 저온저장 후 경도, 가용성 고형물 함량 및 산 함량은 동결피해 발생 전에 수확한 과실보다 낮았다. 결론적으로 가을철 기온이 높은 지역에서 '후지' 과실을 만개 후 180-200일 대비 2-4주 정도 수확시기를 연장시키면 수확시의 가용성 고형물 함량 및 착색이 증가되었으나, 11월 중순 이후로 최저기온이 <TEX>$-3.0^{\circ}C$</TEX> 이하로 떨어지기 시작하기 때문에 11월 중순 이후로 과실을 수확하는 것은 위험하였다. This study was conducted for three years (2007, 2009, and 2010) to investigate the changes in fruit quality during maturation, and the quality and storage ability of fruits harvested at different times of 'Fuji' apple in Daegu region with a high air temperature during the fall season. Changes in apple fruit quality during the maturation period were investigated from 120-135 days to 183-198 days after full bloom. In comparing quality and storage ability of fruits harvested at different times, fruits harvested more than 180 days after full bloom were used. During the maturation period, poor coloring was the problem for 'Fuji' apple in Daegu region by the high air temperature about <TEX>$20^{\circ}C$</TEX>. In comparing quality of fruits harvested at different times, the soluble solid contents and hunter a value were increased by the extended harvest time. Fruit weight during harvest was not affected by different harvest time, while the fruit firmness and titratable acidity during harvest were decreased critically when the freezing damage happened. Ethylene production, fruit firmness, and titratable acidity during cold storage for twenty weeks did not differ according to the different harvest time. Soluble solid contents of fruits harvested at 216 days after full bloom in 2009 were similar at the time of harvest and cold storage. For fruits harvested at 201 days after full bloom, soluble solid content during cold storage was higher than during harvest time. However fruit firmness, soluble solid content, and titratable acidity after cold storage of fruit harvested after freezing damage was lower than those of the fruit harvested before freezing damage. The results show that the extended harvest time of 'Fuji' apples about 2-4 weeks from 180-200 days after full bloom in area with above-air temperature during fall season was seemed to be beneficial to enhancing soluble solid contents and fruit red color, but harvesting after the middle of November was dangerous because minimum air temperature began to fall under <TEX>$-3.0^{\circ}C$</TEX>.

Tangor, an important citrus type, is a hybrid of orange and mandarin and possesses their advantageous characteristics. Fruit quality is an important factor limiting the development of the citrus industry and highly depends on fruit development and ripening programs. However, fruit development and quality formation have not been completely explored in mandarin-orange hybrids. We sequenced the metabolome and transcriptome of three mandarin-orange hybrid cultivars at the early fruiting [90 days after full bloom (DAFB)], color change (180 DAFB), and ripening (270 DAFB) stages. Metabolome sequencing was performed to preliminarily identify the accumulation patterns of primary and secondary metabolites related to fruit quality and hormones regulating fruit development. Transcriptome analysis showed that many genes related to primary metabolism, secondary metabolism, cell wall metabolism, phytohormones, and transcriptional regulation were up-regulated in all three cultivars during fruit development and ripening. Additionally, multiple key genes were identified that may play a role in sucrose, citric acid and flavonoid accumulation, cell wall modification, and abscisic acid signaling, which may provide a valuable resource for future research on enhancement of fruit quality of hybrid citrus. Overall, this study provides new insights into the molecular basis of pulp growth and development regulation and fruit quality formation in mandarin-orange hybrids.

Purpose Organic farming system was considered to increase fruit quality and improve food safety. Moreover, many consumers prefer organic products due to their better taste. Among the Prunus species, apricot is well grown in the world due to its good taste and multi uses. Tunisian apricot cultivars are cultivated in many areas, well adapted and characterized by varied pomological characteristics. In fact, due to the demand of the fresh market, there is growing introduction of commercial cultivars with firmness, visual appeal and flavor as principal traits demanded. Here, we aimed to assess the quality of organic apricot among local and introduced cultivars, in order to identify the cultivar(s) with better fruit quality performances. Research method: For this purpose, morphological (attractiveness, shape, surface, ground color of skin, etc.) and physico-chemical (weight, width, TSS, titrable acidity, etc.) attributes of fruit were studied according to the international descriptors of apricot and to the other investigations on fruit quality. Findings: Few differences of morphological attributes but high significant differences for most physico-chemical attributes of organic fruit were observed between local and introduced apricot cultivars. The organic cultivation system promotes the production of high fruit quality (high value of TSS: > 13°Brix, low value of acidity and big size) for the 3 local cultivars. Limitations: No limitations were founded. Originality/Value: Compared to the introduced apricot cultivars, the local ones are characterized by the performances of their fruit quality and also by their best adaptation under organic cultivation system.

This study aimed to clarify the relationship between grape (Vitis vinifera L.) quality and environmental factors (climate and soil), and to elucidate the theoretical basis and provide technical guidance for the rational planning of the cultivation area and the precise regulation of the cultivation mode in the future. The fruits of three different grape cultivars, Pinot Noir, Merlot, and Vidal, as well as soil samples and meteorological data were collected from three wine grape growing areas (Wuwei, Zhangye, and Jiayuguan) in the Hexi Corridor, Northwest China. Principal-component analysis (PCA) and correlation analysis were conducted to understand the relationship of grape quality with weather conditions and soil properties. The results showed that the titratable acid content of grape berries was significantly negatively correlated with average temperature from August to September, average minimum temperatures from August to September, and from April to October, mean annual minimum temperature, growing degree days from August to September, and soil total nitrogen content, and significantly positively correlated with average rainfall from April to October, annual mean rainfall, and soil available potassium content. In addition, the pH of grape juice was significantly negatively correlated with annual mean rainfall and soil available potassium content. However, it was significantly positively correlated with average temperature and average minimum temperature from August to September, average minimum temperature from April to October, growing degree days from August to September, as well as soil total nitrogen content. In addition, the results of PCA showed that the fruit quality scores of ‘Vidal’ in Jiayuguan, ‘Merlot’ in Zhangye, and ‘Pinot Noir’ in Wuwei were the highest, respectively. In conclusion, the contents of titratable acid, pH, and Brix° are greatly affected by climate and soil factors. ‘Vidal’, ‘Merlot’, and ‘Pinot Noir’ were suitable for planting in Jiayuguan, Zhangye, and Wuwei, respectively. Nowadays, few reports focus on the relationship between grape quality and soil and climate conditions. Based on the investigation and analysis of the differences of climate, soil, and grape berries quality in the three production areas of Hexi Corridor, the relationship among climate, soil, and grape quality by using statistical methods was studied, which could provide references for clarifying the reasons why environmental factors affect grape quality and select the suitable area for wine grape cultivation.

The fruits of myrtle at different stages of development, namely green (G), colour break (C) and mature (M), were used to investigate the changes of fruit quality and anthocyanin composition during its development. Five anthocyanin components, such as delphinidin (Dp), cyanidin (Cy), pelargonidin (Pg), peonidin (Pn) and malvidin (Mv), were detected. Among them, the content of Dp glucoside was the highest (2.12 μg · g−1) and the content of Pn glucoside was the lowest (0.17 μg · g−1) at the green stage. The content of Cy glucoside was the highest (120.94 and 1,200.03 μg · g−1), and the content of Mv glucoside was the lowest (19.50 and 62.72 μg · g−1) at the colour break and mature stages. The single fruit weight, vertical diameter and transverse diameter at the mature stage were significantly higher than those at the colour break and the green stages by 0.87 g, 1.27 mm, 1.53 mm and 1.54 g, 3.4 mm, 3.55 mm, respectively. Fruit quality, the contents of soluble sugar and carotenoids, gradually increased with the development of fruit; and the contents were the highest at the mature stage (17.68% and 16.90 μg · L−1). The contents of titratable acidity, total phenol, flavonoids, chlorophyll a and total chlorophyll gradually decreased with the development of fruit, the content was the lowest at the mature stage (2.71 mmol · 100 g−1, 9.29 μg · g−1, 0.1%, 0.37 μg · L−1, 0.9 μg · L−1) and the content was the highest at the green stage (5.25 mmol · 100 g−1, 21.07 μg · g−1, 0.17%, 8.86 μg · L−1, 15.47 μg · L−1). The difference between the green period and the colour break period was significant.

Developmental metabolomics to decipher and improve fleshy fruit quality

Fruit quality is influenced by cultural management in field, by the fruit picking time and by the storage strategy. The choice of the best techniques and strategies to enhance fruit quality is difficult, and even more complicate is the definition of the internal fruit quality changes occurring in pre- and post-harvest conditions. In fact, internal fruit quality is strictly related to the changes occurring during the ripening and maturation syndrome. Define them with accuracy would allow to verify the techniques adopted validity, to monitor the evolution of the ripening in field and in storage and finally to offer a uniform fruit quality to the consumers. Fruit internal quality is represented by the fruit texture, the sugars and organic acids content, the flavour, etc. Although a precise definition of the quality would require equipped laboratory and knowledgeable personnel, the standard techniques for assessing fruit quality are quite simple (refractometer and penetrometer for flesh soluble solids content and flesh firmness; titration for acidity, etc). These determinations are carried out on samples of a limited number of fruit, often not representative of all the fruit, but give the possibility to have real-time information. However, recently, the availability of non-destructive techniques to assess fruit quality, also offer real-time information, allow to determine quality traits on a high number or even on all the fruit, to repeat the analyses on the same samples monitoring their physiological evolution, to determine with the same measurement a number of information on several fruit quality parameters. Here are reported examples on how the internal fruit quality can be influenced (harvest time, 1-MCP applications, storage strategy) and the possibility offered by NIRs (near infrared spectroscopy) and electronic-nose non-destructive devices to monitor and define fruit quality changes of some fruit specie in pre- and post-harvest situations.

Red-skinned pears with a bright red color and abundant health benefits are favored by consumers. However, fruit coloration and inner quality are usually affected by adverse factors, which lead to a decline in fruit quality and commerciality. Methyl jasmonate (MeJA) has been reported to be involved in many plant processes, including anthocyanin accumulation, while the value of MeJA application for fruit coloration and quality improvement in red-skinned pears is still largely unclear. The application of 0, 0.5, 1.0, or 2.0 mM MeJA at different fruit development stages significantly promoted red coloration in ‘Danxiahong’ pears. Moreover, MeJA treatment increased the fruit soluble solids, improved the total sugar content, decreased the fruit acid content, and significantly increased the total sugar/total acid ratio. However, no significant effect was observed on the fruit’s shape or longitudinal or transverse diameters. RT-qPCR analysis indicated that the expression of anthocyanin biosynthetic regulatory and structural genes, including PbrMYB10, PbrbHLH3, PbrWD40, PbrPAL, PbrCHI, PbrDFR, and other genes, was induced by MeJA treatments. Overall, our findings demonstrate that the application of MeJA plays a significant role in promoting anthocyanin accumulation in pear peels, leading to enhanced fruit coloration. Furthermore, MeJA treatment also positively impacts the improvement of the inner fruit quality. These results not only provide valuable insights into the mechanism of MeJA-mediated coloration but also contribute to a better understanding of the overall role of MeJA in pear fruit development and quality enhancement.

Time-temperature indicators (TTIs) are cost-efficient tools that may be used to predict food quality. In this paper, a diffusion TTI was used to predict fruit quality during storage. Both the color changing characters of TTI and the quality parameters, including weight loss, soluble solids content, vitamin C content, titratable acidity, and antioxidant capacity of three kinds of fruits (kiwifruit, strawberry, and mango), were investigated for storage temperatures (5, 10, 15, and 20°C). The relationships between the color changing properties and fruit quality parameters have been built based on the activation energy (Ea ). The results showed that the storage temperature and time had significant effects on the color changing of TTI and fruit quality. The RGB value of TTI decreased with time, and the higher the storage temperature, the faster the RGB value reduced. Also, the higher the storage temperature, the faster the fruit quality changed and the poorer they were. Furthermore, all of the differences of Ea between TTI color response and fruit quality change are less than 25kJ/mol, which indicates that the TTI can be used to predict these fruit quality. Finally, prediction models were built and validated based on the RGB values of TTI. It provides the possibility for low-cost quality monitoring and has more application potential in food quality predicting. PRACTICAL APPLICATION: By monitoring the color change of diffuse time-temperature indicator (TTI) and the quality change of fruit, the feasibility of TTI for fruit quality monitoring was determined and the quality prediction model was established. The diffusion TTI and fruit quality prediction model can realize the monitoring and predicting of fruit quality based on the TTI, which provides a basis for the combination of TTI Quick Response Code and fruit quality monitoring, with a view to achieving fruit quality status by scanning the Quick Response Code of TTI with mobile phones in the future. This method may provide a new solution to monitor the fruit quality during storage and distribution based on visualization technology that can simplify the methods of detecting fruit quality and achieve fast quality detection. It provides the possibility for low-cost quality monitoring and has more application potential in food quality predicting. Further studies on diffusion TTI are needed to develop its application in more field of food and make the diffusion TTI an intelligent mean for food quality monitoring and predicting.

Effects of climatic variability at different altitudes on the fruit development and quality attributes of kiwifruit in the North -Western Himalayas of India were investigated. The experiment was carried out at five attitudinal locations (1090, 1275, 1425, 1543, and 1924 m above mean sea level) and with two cultivars viz. Hayward and Allison. It was observed that fruit yield and quality varied according to altitude and cultivars. The Hayward cultivar performed better in terms of yield, graded portion, and fruit quality like titratable acidity and ascorbic acid at higher elevations whereas, the Allison cultivar performed better at lower elevations. Findings revealed that the elevation ranging from 1000 to 1450 m was appropriate for the Allison cultivar and the elevation ranging from 1500 to 1950 m was appropriate for the Hayward cultivation. Bangladesh J. Bot. 52(2): 369-379, 2023 (June)