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Jan-Louis Bezuidenhout and Hannes Robbertse

Discoloration of the lenticels of some mango cultivars is a serious problem, affecting the economic value of the fruit. Mango fruit lenticels develop from ruptured stomata on fruit from 20 mm in `TA' and `Keitt' and 30 to 40 mm in `Kent'. Lenticels enlarge as the fruit grow due to stretching of the fruit surface. Adult lenticels of `TA' and `Keitt' are larger in size than those of `Kent'. `Kent' lenticels are also better insulated than `TA' and `Keitt', having a thick cuticle in the lenticel cavity and, in some instances, a phellogen is also present where `TA' and `Keitt' lack both of the above mentioned. Resin present in the skin of the fruit play an important role in the discoloration of `TA' and `Keitt' lenticels. Resin of both `TA' and `Keitt' fruit contain a considerable amount of an aggressive compound termed terpenes. These terpenes are volatile and able to move out of the resin ducts via the sublenticellular cells to the outside of the fruit. The integrity of tonoplasts situated in sublenticellular cells are lost due to the presence of terpenes, causing vacuolar bound phenols to come into contact with polyphenol oxidase, present in the cell walls. The product of the resultant reaction is a quinone, accumulating as a brownish deposit in the cell walls, the black markings visible from the outside. This is the spontaneous discoloration process. Lenticel discoloration may also occur due to maltreatment, i.e., rough handling, to high temperatures, extended period on brushes on the packline, breaking of the cold chain, and spilling of resin onto the surface of the fruit.

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Robyn McConchie and N. Suzanne Lang

Abbreviations: AER, assimilate export rate; CER, carbon exchange rate; DNMR, Duncan's new multiple range test; GSH, reduced glutathione; GSSG, oxidized glutathione; MDA, malionaldehyde; POD, peroxidases; PPO, polyphenol oxidase. 1 Graduate Research

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William J. Sciarappa, Jim Simon, Ramu Govindasamy, Kathleen Kelley, Frank Mangan, Shouan Zhang, Surendran Arumugam, Peter Nitzsche, Richard Van Vranken, Stephen Komar, Albert Ayeni, Gene McAvoy, Chung Park, William Reichert, David Byrnes, Qingli Wu, Brian Schilling, and Ricardo Orellana

The rapid expansion of Asian populations in the United States presents significant opportunities and challenges for the eastern U.S. produce sector to take advantage of their close proximity to densely populated areas. Initial crop studies followed by ethnic consumer and crop surveys were conducted to examine vegetable, leafy green, and herb consumption and expenditures among Chinese, Asian Indians, and other Asian groups. Consumer choices were used to prioritize subsequent production trials. Family expenditures were determined for specific Asian produce types and total produce purchases. This market data were extrapolated to the east coast Asian populations to assess potential market size (90% confidence interval, error margin 5.6%). Chinese consumer values ranged from $245 to $296 million per annum and Asian Indians ranged from $190 to $230 million per annum. The average annual fresh fruit and vegetable expenditures by both Asian groups were 2 to 3.5 times respective national averages. Leading Chinese vegetables determined by average expenditures were baby bok choy, pak choy, oriental eggplant, snow pea, oriental spinach, and napa cabbage. Highest expenditure of leafy greens and herbs for Chinese consumers were chives and garland chrysanthemum. This market-driven survey reported consumption of over 100 Asian crops and 42 cultivars were ranked “feasible” to grow in the eastern section of the United States. Horticultural matrices of selection criteria narrowed the list to the most promising candidates for production. As a result, 28 cultivars were then grown in University research and demonstration plots at Massachusetts, New Jersey, and Florida in determining growth characteristics and yield to focus horticultural crop producers. Leading vegetable cultivars for Asian Indian consumers were bitter gourd, eggplant, fenugreek leaves, cluster beans, and bottle gourd. Leading leafy greens and herbs for Asian Indians were turmeric, fenugreek, sorrel spinach, and radish greens. Most of these Asian cultivars were demonstrated to grow well in the three main growing zones of 5, 7, and 9. Phytochemical attributes such as antioxidant activity, polyphenols, and mineral contents were analyzed for several of the leading crop candidates. This initial field and laboratory data shows that many of these ethnic crops can be grown in the eastern United States to direct production opportunities and are nutrient rich to help drive consumer demand.

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Muttalip Gündoğdu, Tuncay Kan, and Mustafa Kenan Gecer

important for apricot production and processing as a result of its favorable climatic and geographical conditions ( Altindag et al., 2006 ; Ercisli, 2009 ). The apricot varieties contain different levels of polyphenols as summarized by Macheix et al. (1990

Open access

Carol A. Miles, Travis R. Alexander, Gregory Peck, Suzette P. Galinato, Christopher Gottschalk, and Steve van Nocker

particles with a greater ratio of surface area to volume when milled, which allows for more efficient pressing ( Root and Barrett, 2005 ). Achieving a higher polyphenol concentration with less apple tissue could also reduce waste generation in the milling

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Zhongshuai Gai, Yu Wang, Jutang Jiang, Hui Xie, Zhaotang Ding, Shibo Ding, and Hui Wang

( Chen and Zhou, 2005 ). Total tea polyphenols were extracted and determined spectrophotometrically according to the standard method established by the International Organization for Standardization 14502-1 as described by Han et al. (2016) . Gallic acid

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Travis R. Alexander, Thomas S. Collins, and Carol A. Miles

titratable tannin contents of their respective musts ( Barker, 1903 ; Tavernier and Jacquin, 1949 ). Polyphenols also provide protective health benefits via their antioxidant capacity, and regular polyphenol consumption is associated with decreased

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Rui Sun, Hui Li, Qiong Zhang, Dongmei Chen, Fengqiu Yang, Yongbo Zhao, Yi Wang, Yuepeng Han, Xinzhong Zhang, and Zhenhai Han

post-harvest flesh browning in many fruits, including apple. The browning of fresh-cut apple mainly results from enzymatic browning of phenolic compounds, catalyzed by polyphenol oxidase (PPO) in the flesh tissue ( Gil et al., 1998 ). Therefore, flesh

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Mari Loehrlein

fermentation; (3) Investigate changes in polyphenol constituents and free fatty acids of cocoa pulp of Ghanaian beans during fermentation; and (4) Investigate the effects of pulp pre-conditioning and fermentation on the fermentative quality of Ghanaian cocoa

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Jaime Prohens, Adrián Rodríguez-Burruezo, María Dolores Raigón, and Fernando Nuez

(hydroxycinnamic acid derivatives) to be accessible to polyphenol oxidases, which catalyze their oxidation to quinones, which react nonenzymatically with O 2 , sulfhydryl compounds, amines, amino acids, and proteins to give brown-colored compounds ( Ramírez et al