Methods available for the measurement of antioxidant capacity are reviewed, presenting the general chemistry underlying the assays, the types of molecules detected, and the most important advantages and shortcomings of each method. This overview provides a basis and rationale for developing standardized antioxidant capacity methods for the food, nutraceutical, and dietary supplement industries. From evaluation of data presented at the First International Congress on Antioxidant Methods in 2004 and in the literature, as well as consideration of potential end uses of antioxidants, it is proposed that procedures and applications for three assays be considered for standardization: the oxygen radical absorbance capacity (ORAC) assay, the Folin-Ciocalteu method, and possibly the Trolox equivalent antioxidant capacity (TEAC) assay. ORAC represent a hydrogen atom transfer (HAT) reaction mechanism, which is most relevant to human biology. The Folin-Ciocalteu method is an electron transfer (ET) based assay and gives reducing capacity, which has normally been expressed as phenolic contents. The TEAC assay represents a second ET-based method. Other assays may need to be considered in the future as more is learned about some of the other radical sources and their importance to human biology.

https://faculty.missouri.edu/~glaserr/3700s14/Antioxidant-Capacity_jf0502698.pdf

Standardized Methods for the Determination of Antioxidant Capacity and Phenolics in Foods and Dietary Supplements

https://aggie-horticulture.tamu.edu/faculty/cisneros/Papers/Thaipong_2006.pdf

Comparison of ABTS, DPPH, FRAP, and ORAC assays for estimating antioxidant activity from guava fruit extracts

Phenolic compounds in plants and agri-industrial by-products: Antioxidant activity, occurrence, and potential uses

This publication is based on studies carried out from August 2010 to January 2011 by The Swedish Institute for Food and Biotechnology (SIK) on request from the FAO. The two studies on global food losses (one for high/medium-income countries and one for low income countries) have been carried out to serve as a basis for the international congress Save Food!, 16-17 May 2011, at the international packaging industry fair Interpack2011 in Dusseldorf, Germany.
The study highlights the losses occurring along the entire food chain, and makes assessments of their magnitude. Further, it identifies causes of food losses and possible ways of preventing them. The results suggest that roughly one-third of food produced for human consumption is lost or wasted globally, which amounts to about 1.3 billion tons per year. This inevitably also means that huge amounts of the resources used in food production are used in vain, and that the greenhouse gas emissions caused by production of food that gets lost or wasted are also emissions in vain.

Global food losses and food waste: extent, causes and prevention.

Food waste in the global food supply chain is reviewed in relation to the prospects for feeding a population of nine billion by 2050. Different definitions of food waste with respect to the complexities of food supply chains (FSCs)are discussed. An international literature review found a dearth of data on food waste and estimates varied widely; those for post-harvest losses of grain in developing countries might be overestimated. As much of the post-harvest loss data for developing countries was collected over 30 years ago, current global losses cannot be quantified. A significant gap exists in the understanding of the food waste implications of the rapid development of ‘BRIC’ economies. The limited data suggest that losses are much higher at the immediate post-harvest stages in developing countries and higher for perishable foods across industrialized and developing economies alike. For affluent economies, post-consumer food waste accounts for the greatest overall losses. To supplement the fragmentary picture and to gain a forward view, interviews were conducted with international FSC experts. The analyses highlighted the scale of the problem, the scope for improved system efficiencies and the challenges of affecting behavioural change to reduce post-consumer waste in affluent populations.

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Food waste within food supply chains: quantification and potential for change to 2050

/pdf/influence-of-place-packing-or-tray-packing-on-the-cooling-2z31cgm30g.pdf

Influence of Place Packing or Tray Packing on the Cooling Rate of Palletized `Anjou' Pears

ADDITIONAL INDEX WORDS. Persea americana, alternative oxidase, cyanide-resistant respiration, respiratory control, residual respiration ABSTRACT. Partially ripened avocado (Persea americana (Mill.) cv. Hass) fruit harvested in either June or Aug. 1994 were kept at 10 °C in air (21% O2), 20% CO2(17% O2, balance N2), or 40% CO2 (13% O2, balance N2) for 7 to 12 days and then were transferred to air at 10 °C for 2 to 3 days. Mitochondrial respiration was stimulated in response to elevated CO2 treatments at 10 °C. A shift to alternative pathway (Alt) respiration occurred on day 4 in experiments using avocados from both harvest dates, with a return to initial levels in only the 20% CO2-treated fruit (June-harvested fruit after return to air). Elevated CO2 at 20 °C decreased the in vitro O2 consumption of isolated mitochondria compared to mitochondria kept in air. The Alt pathway contributed less to the total O2 uptake of CO2-treated mitochondria compared to mitochondria kept in air. The respiratory control ratios of the CO2-treated fruit and mitochondria were higher and lower, respectively than the air controls. Induction of 33 to 37 kD proteins (corresponding to the size of the alternative oxidase proteins) occurred in avocados after 4 days in 40% CO2. These results indicate that elevated CO2 has various effects depending on concentration, duration and temperature of exposure, and mitochondrial function of avocado fruit, such as increased and altered respiratory oxidation and up- regulation of alternative oxidase proteins.

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Changes in Alternative Pathway and Mitochondrial Respiration in Avocado in Response to Elevated Carbon Dioxide Levels

VII. QUALITY AND QUALITY EVALUATION C. COLOR AND GLOSS 1. AULENBACH, B.B., J.N. Yeatman, and J.T. Worthington. 1972. Quality sorting of Red Delicious apples by light transmission. USDA, Mktg. Res. Rpt. 936, 21 p. 2. BIRTH, G.S. 1979. Radiometric measurement of food quality -A review. J. Food Sci. 44:949-953, 957. 3. CLYDESDALE, F.M. 1976. Instrumental techniques for color measurement of foods. Food Technol. 30(10):52-59. 4. DULL, G.G., G.S. Birth, and J.B. Magee. 1980. Nondestructive evaluation of internal quality. HortScience 15:60-63. 5. FRANCIS, F.J. 1980. Color quality evaluation of horticultural crops. HortScience 15:58-59. 6. FRANCIS, F.J. and F.M. Clydesdale. 1975. Food Colorimetry: Theory and applications. AVI Publ. Co., Westport, CT, 477 p. 7. GUNASEKARAN, S. 1990. Delayed light emission as a means of quality evaluation of fruits and vegetables. Crit. Rev. Food Sci. Nutr. 29:19-34. 8. HUNTER, R.S. 1975. The measurement of appearance, John Wiley & Sons, NY, 348 p. 9. JAHN, O.L. and J.J. Gaffney. 1972. Photoelectric color sorting of citrus fruit. USDA, Tech. Bull. 1448, 56 p. 10. WARD, G., and A. Nussinovitch. 1996. Gloss properties surface morphology relationships of fruits. J. Food Sci. 61: 973-977. See also: Section VI G (Pigments).

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Postharvest handling and physiology of horticultural crops a list of selected references

and temperature conditions between the treatments (Brown and Brown, 1992). In conclusion, foam mulch maintained its integrity for the entire growing season and provided similar weed suppression to the black plastic mulch. Mulch color did not affect weed suppression. This is probably because regardless of color the foam mulch did not allow light penetration and likely served as a physical barrier impeding weed emergence. Mulch color but not mulch type affected early, ripe fruit, and total yield. Yields in blue foam mulch were greater than in the other treatments. Tomato fruit yields in black foam and black plastic mulches were similar. Further research is needed to confirm the effect of blue color on tomato yield and to compare blue foam mulch with blue plastic mulch. Microenvironment monitoring is also needed under foam mulch to determine its effects on the crop environment and to understand how foam mulch impacts tomato growth and yield. Foam mulch is currently being commercialized for use in high-value situations. Foam mulch may also have potential for use in organic vegetable production. At this stage, foam mulch is more costly than plastic mulch and is uneconomical to use on larger conventionally-produced, commercial plantings of tomato or basil. We expect that as application technology is improved and the use of foam mulch becomes more common, the price of foam mulch will decrease and its use in larger vegetable plantings will increase.

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Genotypic Variation in Chilling Sensitivity of Mature-green Bananas and Plantains

Postharvest losses in quantity and quality of tropical and subtropical fruits are commonly very high, especially as many of these fruits are produced in developing countries and transported long distance to markets in developing and developed countries. Biological factors involved in deterioration of fresh fruit quality include the rates of respiration, ethylene production and transpiration and fruit sensitivity to ethylene and also compositional changes that affect color, texture, flavor (taste and aroma) and nutritional quality. Several physiological disorders also reduce fruit quality postharvest. These are the result of products' responses to various environmental and physical stresses, including temperature (the most significant factor), relative humidity, ethylene, atmospheric composition (concentrations of oxygen, carbon dioxide and other gases), and light. Lastly, other biological factors such as disease and insect infestation can reduce fruit quality. There are many opportunities to reduce quality deterioration associated with biological factors by selecting genotypes that have lower respiration and ethylene production rates, less sensitivity to ethylene, slower softening rate, improved flavor quality, enhanced nutritional quality (vitamins, minerals, dietary fiber, and phytonutrients including carotenoids and phenolic compounds), reduced browning potential, decreased susceptibility to chilling injury, and/or increased resistance to postharvest decay-causing pathogens. This chapter describes some of the important biological and environmental factors that influence deterioration rates, therefore causing losses of tropical and subtropical fruits. The potential uses of biotechnological approaches for improving quality and postharvest life are also briefly discussed.

Adel A. Kader

Papers

Influence of Place Packing or Tray Packing on the Cooling Rate of Palletized `Anjou' Pears

Changes in Alternative Pathway and Mitochondrial Respiration in Avocado in Response to Elevated Carbon Dioxide Levels

Postharvest handling and physiology of horticultural crops a list of selected references

Genotypic Variation in Chilling Sensitivity of Mature-green Bananas and Plantains

Postharvest biology of tropical and subtropical fruits.