Evaluation of antioxidants stability by thermal analysis and its protective effect in heated edible vegetable oil

In this work, through the use of thermal analysis techniques, the thermal stabilities of some antioxidants were investigated, in order to evaluate their resistance to thermal oxidation in oils, by heating canola vegetable oil, and to suggest that antioxidants would be more appropriate to increase the resistance of vegetable oils in the thermal degradation process in frying. The techniques used were: Thermal Gravimetric (TG) and Differential Scanning Calorimetry (DSC) analyses, as well as an allusion to a possible protective action of the vegetable oils, based on the thermal oxidation of canola vegetable oil in the laboratory under constant heating at 180 ºC/8 hours for 10 days. The studied antioxidants were: ascorbic acid, sorbic acid, citric acid, sodium erythorbate, BHT (3,5-di-tert-butyl-4-hydroxytoluene), BHA (2, 3-tert-butyl-4-methoxyphenol), TBHQ (tertiary butyl hydroquinone), PG (propyl gallate) - described as antioxidants by ANVISA and the FDA; and also the phytic acid antioxidant and the SAIB (sucrose acetate isobutyrate) additive, which is used in the food industry, in order to test its behavior as an antioxidant in vegetable oil. The following antioxidants: citric acid, sodium erythorbate, BHA, BHT, TBHQ and sorbic acid decompose at temperatures below 180 ºC, and therefore, have little protective action in vegetable oils undergoing frying processes. The antioxidants below: phytic acid, ascorbic acid and PG, are the most resistant and begin their decomposition processes at temperatures between 180 and 200 ºC. The thermal analytical techniques have also shown that the SAIB antioxidant is the most resistant to oxidative action, and it can be a useful choice in the thermal decomposition prevention of edible oils, improving stability regarding oxidative processes.

Chemical characterization of the flour of peel and seed from two papaya cultivars

Papaya is among the currently most important tropical fruits grown in Brazil and in the world. The fruit is mainly consumed fresh although it offers many industrial products. The processing of this fruit, as well as its fresh consumption, results in large amounts of waste, such as peels and seeds. Papaya consumption is one of the causes of significant loss of food value; therefore, new aspects on the use of its waste as by-products, or in the production of food additives, or even the incorporation of its flour in food have aroused great interest because these are products of high nutritional value, and their use may be economically viable. The objective of this study was to produce and characterize peel and seed flours from two papaya cultivars (Havai and Calimosa) for their chemical constituents focusing on possible use in foods. The proximate and mineral composition, titratable acidity, soluble solids, pH, contents of vitamin C, and phenolic compounds were determined. According to the results obtained, the papaya peel and seed flours had high contents of protein and fiber and therefore can be used as alternative sources of nutrients and can also be added in foods avoiding waste and adding value to the fruit.

In vitro antioxidant, antimutagenic and antiproliferative activities of collagen hydrolysates of jumbo squid (Dosidicus gigas) byproducts

AbstractHydrolysates from two different jumbo squid byproducts (fins and arms), produced by trypsin and protease type XIV were compared on the basis of their antioxidant (DPPH and ABTS radical scavenging assays), antimutagenic (Ames test) and antiproliferative (Transformation cell proliferation in M12.C3F6 murine cells) activities. Jumbo squid arms had higher content of collagen than fins, and their hydrolysates had the highest antioxidant activity. Also, jumbo squid arm-derived collagen hydrolyzed with protease XIV showed the highest antimutagenic activity. The four hydrolysates obtained showed low antiproliferative activity, however they are susceptible for further studies to be applied as food additives.

Cytotoxic and genotoxic potential of powdered juices

Abstract Powdered juices are widely consumed by the population especially because of their convenient preparation, availability in various fruit flavors and low cost when compared to other industrialized beverages. They have complex formulation, consisting of several classes of food additives. However, there are no scientific studies on the toxicity of these foods. Thus, this study evaluated the toxicity at the cellular level of industrialized powdered juices of orange and guava flavors of three different food companies. This analysis was made using root meristem cells of Allium cepa L., at the exposure times of 24 and 48 hours, and two concentrations, 30 g/1000 mL, considered ideal for consumption according to the label of the products, and 30 g/500 mL. Both flavors of juices, of the three companies, in both concentrations and the two exposure times promoted significant antiproliferative effect to root meristem cells and caused a statistically significant number of mitotic spindle changes and micronuclei in cells of the test system used. Therefore, under the studied conditions, all the samples of juice powder exhibited cytotoxic and genotoxic potential.

An educator's perspective of Dr. Feingold's K-P (Kaiser- Permanents) elimination diet for hyperkinetic children and others

Do evaluation of the literature and a regional observational report support Dr. Feingold's claim that the K-P (Kaiser-Permanente) elimination diet improves the behaviours of hyperkinetic children, and others? Dr. Feingold suggests that some hyperkinetic children, and other children as well, are genetically predisposed to intolerance of food additives, particularly food colours and flavours. He claims that the K-P diet, that eliminates salicylates and artificial food colours and flavours, improves the hyperkinetic child's behaviour, muscle co-ordination, and scholastic performance. Public acceptance of the K-P diet has outstripped acceptance in the medical and scientific communities. Evaluation of available data and additional studies are needed to arrive at a conclusion of acceptance or rejection of the K-P diet for hyperkinetic children and others. My interest in the K-P elimination diet for hyperkinetic children is educational. My experience as an elementary school teacher in special education and in the classroom from K-8 has taught me that attentiveness is crucial to learning. Hyperkinesis appears to impair a child's ability to attend. Learning problems appear, followed by behavioural and social problems. l If we accept the possibility of a relationship between diet and attentiveness, and attentiveness and school behaviours, then the diet-behaviour link could be of lay importance. For instance, if a diet such as the K-P diet could do what is claimed, substantial benefits could accrue to the child. One could, for example, improve a child's behaviours. One could identify attending disturbances early in the child's education, possibly minimizing, or eliminating future difficulties in school. Finally, the greatest benefit may be the fulfillment of the basic goal of our Ontario schools, that the eh~ld-,lIla1p.evelop happily and competently within our educational framework. 2 This thesis reports evidence from the literature and from a regional observational investigation to determine the possibility of a link between the behaviours of children and Dr. Feingold's K-P elimination diet. The literature research examines (1) Dr. Feingold's concept of H-LD, (2) his K-P elimination diet, and (3) the response from three sectors, medicine, science, and the public. The regional investigation examines the observed behaviours of nine children in Regional Niagara during a nine-month period on the K-P diet.

Assessment of meat authenticity using bioinformatics, targeted peptide biomarkers and high-resolution mass spectrometry

In recent years, we observed a significant increase of food fraud ranging from false label claims to the use of additives and fillers to increase profitability. Recently in 2013, horse and pig DNA were detected in beef products sold from several retailers. Mass spectrometry has become the workhorse in protein research and the detection of marker proteins could serve for both animal species and tissue authentication. Meat species authenticity will be performed using a well defined proteogenomic annotation, carefully chosen surrogate tryptic peptides and analysis using a hybrid quadrupole-Orbitrap mass spectrometer. Selected mammalian meat samples were homogenized, proteins were extracted and digested with trypsin. The samples were analyzed using a high-resolution mass spectrometer. The chromatography was achieved using a 30 minutes linear gradient along with a BioBasic C8 100 × 1 mm column at a flow rate of 75 µL/min. The mass spectrometer was operated in full-scan high resolution and accurate mass. MS/MS spectra were collected for selected proteotypic peptides. Muscular proteins were methodically analyzed in silico in order to generate tryptic peptide mass lists and theoretical MS/MS spectra. Following a comprehensive bottom-up proteomic analysis, we were able to detect and identify a proteotypic myoglobin tryptic peptide [120-134] for each species with observed m/z below 1.3 ppm compared to theoretical values. Moreover, proteotypic peptides from myosin-1, myosin-2 and -hemoglobin were also identified. This targeted method allowed a comprehensive meat speciation down to 1% (w/w) of undesired product.

Studies on the Bioactive Natural Antioxidants From Oilseeds

Antioxidants are substances that when present at low concentrations compared to that of an oxidisable substrate significantly delays or inhibits oxidation of that substrate in food products or in living systems. Antioxidants are either endogenous to the body or derived from the diet. Several types of synthetic antioxidants like BHT, BHA, TBHQ etc. are also used in the food industry. However, findings and subsequent publicity has fostered significant consumer resistance to the use of synthetic food additives as antioxidants, colourants etc. and therefore food industry is in search of potential natural antioxidants from edible sources.The major dietary sources of antioxidant phytochemicals are cereals, legumes, fruits, vegetables, oilseeds, beverages, spices and herbs. In the present study, we have focused on rice bran and its byproducts. Rice is one of the oldest of food crops and has been a staple food in India from very ancient times. It is also the staple food for about 60% of the world's population. Rice bran is a byproduct of the rice milling industry and is a potential commercial source of a healthy edible oil viz. rice bran oil and a variety of bio-active phytochemicals.Defatted rice bran (DRB), a byproduct of rice bran oil extraction, is also a good source of insoluble dietary fiber, protein, phytic acid, inosito I, vitamin B and a variety of other phytochemicals. Though the antioxidant potential of DRB has been demonstrated, it still remained a relatively unexplored source material, which demanded further investigation especially with regard to its detailed phytochemical profile leading to practical application. The focus of the present investigation therefore has been on DRB primarily to establish its phytochemical status and feasibility of using it as a source of bio-active phytochemicals and natural antioxidants leading to value addition of DRB otherwise used as cattle feed. To gain a better understanding of the value of rice bran as a source of phytochemicals, five popular rice varieties of the region viz. PTB 50, PTB 39, PTB 38, JA Y A, and MO 10 and a wild variety (oryza nivara) that is mainly used for medicinal applications in traditional ayurvedic system were characterized along with commercial samples of rice bran. The present study also explains the feasibility of a process for the extraction, enrichment, and isolation of antioxidant compounds from DRB. The antioxidant potential of the extracts were evaluated both in bulk oils and in food relevant model emulsions, using standard in vitro models. Radical scavenging effects, indicative of possible biological effects, were also evaluated.

“Effect of spice oleoresins in microbial decontamination and their potential application in quality stabilization of Tuna (Euthynnus affinis) during storage”

Unprocessed seafood harbor high number of bacteria, hence are more prone to spoilage. In this circumstance, the use of spice in fish for reduction of microorganism can play an important role in seafood processing. Many essential oils from herbs and spices are used widely in the food, health and personal care industries and are classified as GRAS (Generally regarded as safe) substances or are permitted food additives. A large number of these compounds have been the subject of extensive toxicological scrutiny. However, their principal function is to impart desirable flavours and aromas and not necessarily to act as antimicrobial agents. Given the high flavour and aroma impact to plant essential oils, the future for using these compound as food preservatives lies in the careful selection and evaluation of their efficacy at low concentrations but in combination with other chemical preservatives or preservation processes. For this reason they are worth of study alone or in combination with processing methods in order to establish if they could extend the shelf-life of foods. In this study, the effect of the spices, clove, turmeric, cardamom, oregano, rosemary and garlic in controlling the spoilage and pathogenic bacteria is investigated. Their effect on biogenic amine formation in tuna especially, histamine, as a result of bacterial control is also studied in detail. The contribution of spice oleoresin in the sensory and textural parameters is investigated using textural profile analysis and sensory panel. Finally, the potential of spices in quality stabilization and in increasing the shelf–life of tuna during frozen storage is analysed

Development of Electrochemical and Fluorescent Sensors

Chemical sensors have growing interest in the determination of food additives, which are creating toxicity and may cause serious health concern, drugs and metal ions. A chemical sensor can be defined as a device that transforms chemical information, ranging from the concentration of a specific sample component to total composition analysis, into an analytically useful signal. The chemical information may be generated from a chemical reaction of the analyte or from a physical property of the system investigated. Two main steps involved in the functioning of a chemical sensor are recognition and transduction. Chemical sensors employ specific transduction techniques to yield analyte information. The most widely used techniques employed in chemical sensors are optical absorption, luminescence, redox potential etc. According to the operating principle of the transducer, chemical sensors may be classified as electrochemical sensors, optical sensors, mass sensitive sensors, heat sensitive sensors etc. Electrochemical sensors are devices that transform the effect of the electrochemical interaction between analyte and electrode into a useful signal. They are very widespread as they use simple instrumentation, very good sensitivity with wide linear concentration ranges, rapid analysis time and simultaneous determination of several analytes. These include voltammetric, potentiometric and amperometric sensors. Fluorescence sensing of chemical and biochemical analytes is an active area of research. Any phenomenon that results in a change of fluorescence intensity, anisotropy or lifetime can be used for sensing. The fluorophores are mixed with the analyte solution and excited at its corresponding wavelength. The change in fluorescence intensity (enhancement or quenching) is directly related to the concentration of the analyte. Fluorescence quenching refers to any process that decreases the fluorescence intensity of a sample. A variety of molecular rearrangements, energy transfer, ground-state complex formation and collisional quenching. Generally, fluorescence quenching can occur by two different mechanisms, dynamic quenching and static quenching. The thesis presents the development of voltammetric and fluorescent sensors for the analysis of pharmaceuticals, food additives metal ions. The developed sensors were successfully applied for the determination of analytes in real samples. Chemical sensors have multidisciplinary applications. The development and application of voltammetric and optical sensors continue to be an exciting and expanding area of research in analytical chemistry. The synthesis of biocompatible fluorophores and their use in clinical analysis, and the development of disposable sensors for clinical analysis is still a challenging task. The ability to make sensitive and selective measurements and the requirement of less expensive equipment make electrochemical and fluorescence based sensors attractive.

Carbohydrate-based anti-adhesive inhibition of Vibrio cholerae toxin binding to GM1-OS immobilized into artificial planar lipid membranes

We have studied 'food grade' sialyloligosaccharides (SOS) as anti-adhesive drugs or receptor analogues, since the terminal sialic acid residue has already been shown to contribute significantly to the adhesion and pathogenesis of the Vibrio cholerae toxin (Ctx). GM1-oligosaccharide (GM1-OS) was immobilized into a supporting POPC lipid bilayer onto a surface plasmon resonance (SPR) chip, and the interaction between uninhibited Ctx and GM1-OS-POPC was measured. SOS inhibited 94.7% of the Ctx binding to GM1-OS-POPC at 10 mg/mL. The SOS EC50 value of 5.521 mg/mL is high compared with 0.2811 mu g/mL (182.5 pM or 1.825 x 10(-10) M) for GM1-OS. The commercially available sialyloligosaccharide (SOS) mixture Sunsial E (R) is impure, containing one monosialylated and two disialylated oligosaccharides in the ratio 9.6%. 6.5% and 17.5%, respectively, and 66.4% protein. However, these inexpensive food-grade molecules are derived from egg yolk and could be used to fortify conventional food additives, by way of emulsifiers, sweeteners and/or preservatives. The work further supports our hypothesis that SOS could be a promising natural anti-adhesive glycomimetic against Ctx and prevent subsequent onset of disease. (C) 2009 Elsevier Ltd. All rights reserved

Acrylamide concentrations in potato crisps in Europe from 2002 to 2011

A dataset of manufacturers' measurements of acrylamide levels in 40,455 samples of fresh sliced potato crisps from 20 European countries for years 2002 to 2011 was compiled. This dataset is by far the largest ever compiled relating to acrylamide levels in potato crisps. Analysis of variance was applied to the data and showed a clear, significant downward trend for mean levels of acrylamide, from 763 +/- 91.1 ng g(-1) (parts per billion) in 2002 to 358 +/- 2.5 ng g(-1) in 2011; this was a decrease of 53% +/- 13.5%. The yearly 95th quantile values were also subject to a clear downward trend. The effect of seasonality arising from the influence of potato storage on acrylamide levels was evident, with acrylamide in the first 6 months of the year being significantly higher than in the second 6 months. The proportion of samples containing acrylamide at a level above the indicative value of 1000ngg(-1) for potato crisps introduced by the European Commission in 2011 fell from 23.8% in 2002 to 3.2% in 2011. Nevertheless, even in 2011, a small proportion of samples still contained high levels of acrylamide, with 0.2% exceeding 2000ngg(-1).

Survey of aflatoxin M1 in cheese from the North-east region of Sao Paulo, Brazil

In the present study, 24 samples of Minas Frescal cheese and 24 samples of Minas Padrao cheese produced in the North-east region of the state of Sao Paulo, Brazil, were analysed for aflatoxin M1 (AFM1) by high-performance liquid chromatography (HPLC) between March and August 2008. AFM1 was detected in 13 (27.1%) samples at concentrations ranging from 0.037 to 0.313 ng g-1. The mean concentrations of AFM1 in positive samples of Minas Frescal and Minas Padrao cheese were 0.142 +/- 0.118 and 0.118 +/- 0.054 ng g-1, respectively. It is concluded that the incidence of AFM1 in Minas cheese may contribute to an increase in the overall ingestion of aflatoxins in the diet, hence indicating the need for the adoption of a tolerance limit for AFM1 in cheese in Brazil.

Aflatoxins and cyclopiazonic acid in feed and milk from dairy farms in Sao Paulo, Brazil

The occurrence of aflatoxins (AF) B(1), B(2), G(1), G(2) and cyclopiazonic acid (CPA) in feeds, and AFM(1) and CPA in milk was determined in dairy farms located in the northeastern region of Sao Paulo state, Brazil, between October 2005 and February 2006. AF and CPA determinations were performed by HPLC. AFB(1) was found in 42% of feed at levels or 1.0-26.4 mu g kg(-1) (mean: 7.1 +/- 7.2 mu g kg(-1)). The concentrations of AFM(1) in raw milk varied between 0.010 and 0.645 mu g l(-1) (mean: 0.104 +/- 0.138 mu g l(-1)). Only one sample was above the tolerance limit adopted in Brazil (0.50 mu g l(-1)) for AFM(1) in milk. Regarding CPA in feed, six (12%) samples showed concentrations of 12.5-1533 mu g kg(-1) (mean: 57.6 +/- 48.7 mu g kg(-1)). CPA was detected in only three milk samples (6%) at levels of 6.4, 8.8 and 9.1 mu g l(-1). Concentrations of aflatoxins and CPA in feed and milk were relatively low, although the high frequency of both mycotoxins indicates the necessity to continuously monitor dairy farms to prevent contamination of feed ingredients.

Photocatalytic Decolorization of Commercial Acid Dyes using Solar Irradiation

This work investigates the solar heterogeneous photocatalytic degradation of three commercial acid dyes: Blue 9 (C.I. 42090), Red 51 (C.I. 45430), and Yellow 23 (C.I. 19140). TiO(2) P25 from Degussa was used as the photocatalyst. The dyes were completely degraded within 120 min of treatment in the following increasing order of removal rate: Blue 9 < Yellow 23 < Red 51. The photocatalytic color removal process was well described by a two-first-order in-series reaction, followed by another first-order reaction. Photolytic experiments showed that this process is quite inefficient and highly selective towards Red 51 only. The dyes` solution was completely decolorized and organic matter removals up to 99% were achieved with photocatalysis. The lack of selectivity and the possibility of using solar light to excite the photocatalyst are promising results regarding the feasibility of this technology.

Effect of ion supplementation of a commercial soft drink on tooth enamel erosion

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)