Polyphenols and disease risk in epidemiologic studies

Recently, research on natural antioxidants has become increasingly active in various fields. Accordingly, numerous articles on natural antioxidants, including polyphenols, flavonoids, vitamins, and volatile chemicals, have been published. Assays developed to evaluate the antioxidant activity of plants and food constituents vary. Therefore, to investigate the antioxidant activity of chemical(s), choosing an adequate assay based on the chemical(s) of interest is critical. There are two general types of assays widely used for different antioxidant studies. One is an assay associated with lipid peroxidations, including the thiobarbituric acid assay (TBA), malonaldehyde/high-performance liquid chromatography (MA/HPLC) assay, malonaldehyde/gas chromatography (MA/GC) assay, β-carotene bleaching assay, and conjugated diene assay. Other assays are associated with electron or radical scavenging, including the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) as...

Antioxidant assays for plant and food components.

Nanotechnology is an enable technology that has the potential to revolutionize agriculture and food systems. Driven by increasing consumer demand for healthy food products, researchers have been applying tools and knowledge in nanotechnology to address the issues relevant to food and nutrition. This concise review is mainly focused on nanoemulsions and polymer micelles-based delivery systems which have shown enhanced oral bioavailability and biological efficacies (that is, antiinflammation, anti-cancer, and so on) of different phytochemicals. Nanoemulsions are a class of extremely small droplets that appear to be transparent or translucent with a bluish coloration. They are usually in the range 50 to 200 nm but much smaller than the range (from 1 to 100 mum) for conventional emulsions. Nanoemulsion preparation, characterization, and bioavailability have been discussed. Curcumin nanoemulsions show 85% inhibition of TPA-induced mouse ear inflammation as well as the inhibition of cyclin D1 expression, while dibenzoylmethane (DBM) nanoemulsion shows about 3-fold increase in oral bioavailability compared to the conventional DBM emulsion. Biopolymer micelles show significantly improved water solubility/dispersibility and in vitro anti-cancer activity of phytochemicals. More research efforts are still needed for the understanding of the potential impacts of nanoencapsulated phytochemicals on the human body and environment to address the public concerns.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1750-3841.2009.01457.x

Bioavailability and delivery of nutraceuticals using nanotechnology.

Epidemiological studies have noted a consistent association between the consumption of diets rich in fruits and vegetables and a lower risk for chronic diseases including cancer and cardiovascular disease. There is accumulating evidence that much of the health-promoting potential of these plant foods may come from phytochemicals, bioactive compounds not designated as traditional nutrients. In strawberries, the most abundant of these are ellagic acid, and certain flavonoids: anthocyanin, catechin, quercetin and kaempferol. These compounds in strawberries have potent antioxidant power. Antioxidants help lower risk of cardiovascular events by inhibition of LDL-cholesterol oxidation, promotion of plaque stability, improved vascular endothelial function, and decreased tendency for thrombosis. Furthermore, strawberry extracts have been shown to inhibit COX enzymes in vitro, which would modulate the inflammatory process. Individual compounds in strawberries have demonstrated anticancer activity in several different experimental systems, blocking initiation of carcinogenesis, and suppressing progression and proliferation of tumors. Preliminary animal studies have indicated that diets rich in strawberries may also have the potential to provide benefits to the aging brain.

Potential impact of strawberries on human health: a review of the science.

Aspartame is a methyl ester of a dipeptide used as a synthetic nonnutritive sweetener in over 90 countries worldwide in over 6000 products. The purpose of this investigation was to review the scientific literature on the absorption and metabolism, the current consumption levels worldwide, the toxicology, and recent epidemiological studies on aspartame. Current use levels of aspartame, even by high users in special subgroups, remains well below the U.S. Food and Drug Administration and European Food Safety Authority established acceptable daily intake levels of 50 and 40 mg/kg bw/day, respectively. Consumption of large doses of aspartame in a single bolus dose will have an effect on some biochemical parameters, including plasma amino acid levels and brain neurotransmitter levels. The rise in plasma levels of phenylalanine and aspartic acid following administration of aspartame at doses less than or equal to 50 mg/kg bw do not exceed those observed postprandially. Acute, subacute and chronic toxicity studies with aspartame, and its decomposition products, conducted in mice, rats, hamsters and dogs have consistently found no adverse effect of aspartame with doses up to at least 4000 mg/kg bw/day. Critical review of all carcinogenicity studies conducted on aspartame found no credible evidence that aspartame is carcinogenic. The data from the extensive investigations into the possibility of neurotoxic effects of aspartame, in general, do not support the hypothesis that aspartame in the human diet will affect nervous system function, learning or behavior. Epidemiological studies on aspartame include several case-control studies and one well-conducted prospective epidemiological study with a large cohort, in which the consumption of aspartame was measured. The studies provide no evidence to support an association between aspartame and cancer in any tissue. The weight of existing evidence is that aspartame is safe at current levels of consumption as a nonnutritive sweetener.

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Aspartame: A Safety Evaluation Based on Current Use Levels, Regulations, and Toxicological and Epidemiological Studies

Part I. Introduction to Food Components.- Evaluation of Food Quality.- Water.- Part II. Carbohydrates in Food.- Carbohydrates in Food: An Introduction.- Starches in Food.- Pectins and Gums.- Grains: Cereals, Flour, Rice, and Pasta.- Vegetables and Fruits.- Part III. Proteins in Food.- Proteins in Foods: An Introduction.- Meat, Poultry, Fish, and Dry Beans.- Eggs and Egg Products.- Milk and Milk Products.- Part IV. Fats in Food.- Fats and Oils in Products.- Food Emulsions and Foams.- Part V. Sugars, Sweeteners.- Sugars, Sweeteners, and Confections.- Part VI. Baked Products.- Baked Products: Batters and Dough.- Part VII. Aspects of Food Preservation.- Food Preservation.- Food Additives.- Food Packaging.- Part VIII. Food Safety.- Food Safety.- Part IX. Government Regulation of the Food Supply.- Government Regulation of the Food Supply and Labeling.- Appendices.

Essentials of Food Science

Vegetables are the edible portion of plants eaten with (or as) the main course. They are in salads and soups. Vegetables may be processed into beverages or vegetable starches, eaten fresh or lightly processed, dried, pickled, or frozen. They impart their own characteristic flavor, color, and texture to diets, and undergo changes during storage and cooking. Ranked next to the cereal crops wheat, rice, and corn, potatoes are the most prolific vegetable crop grown for human consumption.

Vegetables and Fruits

Food quality is an important concept because the food people choose depends largely on quality. Consumer preference is important to the food manufacturer, who wants to gain as wide a share of the market for the product as possible. Quality is difficult to define precisely, though it refers to the degree of excellence of a food and includes all the characteristics of a food that are significant and that make the food acceptable.

Evaluation of Food Quality

Fundamentos de ciencia de los alimentos

https://link.springer.com/content/pdf/10.1007%2F978-0-387-69940-0_17.pdf

Elizabeth W. Christian

Papers

Essentials of Food Science

Vegetables and Fruits

Evaluation of Food Quality

Fundamentos de ciencia de los alimentos

Food Preservation and Processing