Fully developed and ripe guava (Psidium guajava L.) fruits harvested during Sept-Dec 1993, from field-grown trees which were winter protected by 6-mil clear polyethylene, were examined for physical characteristics and nutrient contents. The purpose of this study was to establish optimum harvest time, fruit yield and physical characters, and nutritional fluctuations over a five week storage time. Fruits picked at turning stage, were observed for fresh weight, fruit girth (horizontal) and height (vertical), fruit volume, and fruit surface & flesh color evaluation (L* a* b* values by chromameter CR-200, Minolta Corp). Nutritional analysis (proximates, vitamins, and minerals) of fruits harvested on Oct 11, Oct 18, Oct 25, Nov 1, and Nov 8 and, refrigerated until analyzed, was performed at Food Science Department, University of Georgia. There were 342 fruits/tree with an average weight of 292 g, fruit girth 26.1” and height 7.5”. L* a* b* values for surface and flesh colors were. +65.61. -6.86, +39.37, and +55.86, +35.41, +19.48, respectively. Nutritional analyses indicated that the guava fruits were high in vitamin C (305 mg per 100 g fruit). K (201 mg), protein (1.4 g) and total dietary fiber (5.1 g) but low in fat (0.19 g per 100 g fruit) and Na (1.3 mg). The harvested fruit kept well for a five weeks period under refrigerated storage. Except for a modest loss of moisture, the storage period showed no significant effect on nutrient contents in the proximates, vitamins or mineral analyses indicating value of cool storage for guavas.
Jed W. Fahey and Paul Talalay
High fruit and vegetable consumption is associated with a striking reduction in susceptibility to malignancy. In addition to other health benefits (e.g., high levels of vitamin C, carotenoids, and dietary fiber), cruciferous vegetables contribute significantly to this chemoprotective effect. Cruciferous vegetables (e.g. Brassica sp.), contain glucosinolates, water-soluble secondary metabolites that are converted to highly reactive isothiocyanates as a defense response to predation or injury. When fed to mammals, isothiocyanates induce Phase 2 enzymes such as glutathione-S-transferase and quinone reductase, that detoxify xenobiotics. Phase 2 enzyme induction potential was assessed for fruits and vegetables from a wide variety of plant families and the Brassica vegetables were particularly rich in such activity. Tremendous variability in glucosinolate content and Phase 2 enzyme induction potential was found between commercial broccoli cultivars (n = 12) and between sites (n = 7) growing transplants produced at the same time, from the same seedlot. Broccoli (B. oleracea var. italica) cvs. Green Comet and Excelsior had an almost identical spatial distribution of Phase 2 enzyme induction potential that varied by position on market-stage plants. Fertilization regime also affected Phase 2 enzyme induction by these two cultivars. Additionally, induction of detoxication enzymes and glucosinolate profiles have been evaluated in primary and axillary shoots of two greenhouse-grown broccoli cultivars (Broccolo Natalino and a proprietary hybrid), harvested over the duration of a 2-month period of side-shoot production. This approach to evaluating the germplasm, positional, temporal, and cultural effects on levels of inducers of mammalian detoxication enzymes should lead to development of cultivation strategies to enhance the chemoprotective effect of Cruciferous vegetables.
Jinghua Guo, Yan Yan, Lingdi Dong, Yonggang Jiao, Haizheng Xiong, Linqi Shi, Yu Tian, Yubo Yang, and Ainong Shi
.9 billion in 2016 ( Mordor Intelligence, 2018 ). The market is likely to register a promising 6.50% compound annual growth rate between 2017 and 2025. Green-leaf vegetables are considered to be a good source of ascorbic acid (vitamin C), beta carotene, iron
Sat Pal Sharma, Daniel I. Leskovar, Kevin M. Crosby, and A.M.H. Ibrahim
al., 2008 ), though some reports on yield and component traits from India are available ( Dhakare and More, 2008 ; Yadav and Ram, 2010 ). Sweetness, flavor, texture and phytonutrient levels of β-carotene and vitamin C in flesh tissue are the
Jeffrey M. Hamilton and Jorge M. Fonseca
Increased consumption of fruits and vegetables is associated with a lower incidence of numerous cancers and cardiovascular diseases ( Surh, 2003 ). The daily intake of plant phenolics and vitamin C, both known for their high antioxidant capacity
Yu Wang, Haobo Yang, Shuai Zhong, Xin Liu, Tong Li, and Chengwen Zong
. uliginosum fruit ( Wei et al., 2014 ). Vitamin C is a well-known antioxidant ( Kalt et al., 1999 ). Fediuk et al. (2002) reported that V. uliginosum fruit contain abundant vitamin C. During ripening, acid content changes due to the accumulation of sugars
Desire Djidonou, Amarat H. Simonne, Karen E. Koch, Jeffrey K. Brecht, and Xin Zhao
Tomato ( Solanum lycopersicum L.) is a major vegetable crop widely grown and consumed (fresh and processed forms) throughout the world. Tomato fruit are rich sources of nutritional components with antioxidant activity such as vitamin C, phenolics
in texture, and good for both fresh eating and drying. A special note for ‘Shuimen’ is its relatively low vitamin C content compared with other jujube cultivars ( Yao, 2014 ). In China, after thousands of years of cultivation, most cultivars were
jujube are small and puffy without much flesh between the skin and the seed; however, it has higher vitamin C and titratable acid contents than jujube cultivars ( Wang et al., 1956 ). Indian jujube, or ber, is also from the same genus ( Ziziphus
requiring an increase in consumption. Spinach is one of the most desirable leafy vegetables due to its high content of β-carotene (provitamin A), lutein, folate, vitamin C, calcium, iron, phosphorus, and potassium. The red color of ‘USDA Red’ comes from