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Over the last decade a considerable increase in the number of studies addressing the use of antioxidants from natural sources has led to the identification and understanding of the potential mechanisms of biologically active components. This results from the fact that they can be used to replace synthetic antioxidants commonly used in food. Murtilla (Ugni molinae Turcz) is a native berry grown in Chile, and in the present study, the phenolic composition and antioxidant activity of its fruits were studied. Hydroalcoholic extracts of dehydrated fruits from two genotypes of murtilla (Ugni molinae Turcz.) were produced. Extracts of wild murtilla and 14-4 genotype fruits had 19.35 and 40.28mg GAE/g for Total Phenolic Compounds, 76.48, and 134.35μmol TEAC/g for DPPH, and 157.04 and 293.99 μmol TEAC/g for ABTS, respectively. Components such as quercetin, epicatechin, and gallic, benzoic and hydrocaffeic acids were identified by CG/MS analysis. All of them showed antioxidant activity. Therefore, it is possible to say that the hydroalcoholic extracts of murtilla have antioxidant potential to be used in lipidic food.

The effectiveness of grape extracts as food ingredient has been tested in various systems. The objective of this study was to evaluate the efficiency of four concentrations of residues of the wine industry in delaying lipid oxidation in processed chicken meat stored under refrigeration. The development of oxidation during the 14-day storage was evaluated through the thiobarbituric acid reactive substances method (TBAS). The analyses of phenolic compounds and antioxidant activity were performed in grape residue extracts through DPPH (1,1-difenil-2-picrilidrazil) method, lipid peroxidation inhibition and Rancimat. The profile of polyphenols was determined using reversed-phase high-performance liquid chromatography. Isabel grape extract (IGE) and Niagara grape extract (NGE) showed significant content of phenolic compounds. NGE and IGE had high antioxidant activity. The addition of grape extracts significantly increased the oxidative stability of processed and cooked chicken meat during the storage time. The extracts from both grape varieties when applied in concentrations of 40 and 60 mg of GAE, presented results similar to that of Butyl hydroxy toluene (BHT).

Dietary oxidized poultry offal fat: performance, carcass and meat composition, and oxidative stability of frozen thigh meat of broiler chickens ABSTRACT -Two hundred male Ross broiler chicks were raised from 10 to 40 days of age and fed a corn-soy diet with 4% of fresh or oxidized poultry offal fat to evaluate the effects of dietary fat quality on broiler performance and on oxidative stability of frozen thigh meat during storage. Fresh poultry fat, characterized by low concentration of oxidation products determined by specific absorbances of 5.80 and 0.69 at 232 and 270 nm, respectively, was supplied by a local renderer and stored frozen (-18 o C) until diets were produced. Oxidized poultry fat was obtained by heating the fresh poultry fat in a fryer at 110-120 o C until specific absorbances reached 11.33 (at 232 nm) and 2.31 (at 270 nm), which show increased concentration of oxidation compounds. At 41 days of age, 136 birds were slaughtered and carcass characteristics were evaluated. Skinless and deboned raw thigh meat was packed and stored for 9 months in a non-illuminated freezer at -20 o C. Thiobarbituric acid reactive substances (TBARS) were assessed monthly in the frozen samples to evaluate the oxidative status of stored meat. Birds performance and carcass characteristics were not affected by the presence of oxidized poultry fat in the diet. After six months of storage, the oxidative stability of frozen thigh meat from broilers fed oxidized poultry fat was reduced, indicated by higher TBARS values.Key Words: carcass and meat yield, chicken meat quality, lipid oxidation, meat color, TBARS IntroduçãoNa avicultura moderna, óleos e gorduras são incorporados às dietas objetivando, principalmente, fornecer grande quantidade de energia e ácidos graxos essenciais, melhorar a conversão alimentar e a palatabilidade das rações, reduzir o incremento calórico, facilitar a absorção das vitaminas lipossolúveis, além de apresentar outras vantagens operacionais na fábrica de rações.

Cold-pressed Brazil nut oil (BNO) is a valueadded nontimber forest coproduct of market interest, despite the lack of knowledge about its ambient storage stability. The objective of the present study was to investigate oxidative changes in BNO stored in clear and brown glass bottles under retail conditions with a focus on monitoring for the first time the formation of volatile aroma compounds (VAC), the depletion of tocopherol analogs, and the tendency of radical formation. VAC, whose formation continuously increased and correlated with storage time, were detected using headspacesolid-phase microextraction-gas chromatography-mass spectrometry. Depletion of tocopherols was more pronounced for the oil stored in clear glass bottles and the content loss was higher for alpha-tocopherol than for gamma-tocopherol. Furthermore, the tendency of radical formation was detected using a spin-trapping electron spin resonance spectroscopy method, which was demonstrated to be a simpler, faster, and less sample-demanding tool to monitor the oxidative status of BNO stored under retail conditions and its results significantly correlated with those obtained using traditional methods for the determination of primary oxidation products. However, the simultaneous measurement of key off-flavor volatiles is recommended for samples with unknown history. J Am Oil Chem Soc (2018) 95: 721-730 722 J Am Oil Chem Soc J Am Oil Chem Soc (2018) 95: 721-730

Um aumento no índice de peróxido diretamente proporcional à radiação absorvida por grãos foi observado por Hanis et al. (1988), entretanto, mesmo pertencendo à classe dos constituintes de alimentos mais sensíveis à irradiação, em doses superiores a 10 kGy, não se observou alteração significativa nos lipídios dos cereais.

The Brazil nut is an important product from the Amazonian region and its productive chain is an income source for local communities. The effect of combinations of packaging atmospheres (loose or vacuum-packed) and storage temperatures (4±1 °C or 24±2 °C) on the tendency of lipid radical formation and on volatiles was investigated for the first time in shelled Brazil nut kernels. It was observed that refrigeration, whether combined with lose packing or vacuum packing, was effective to reduce the tendency for lipid radical formation, as detected by spin-trapping electron spin resonance (ESR) spectroscopy, as well as peroxides, conjugated dienes and 3-octen-2-one. However, the combination of refrigeration with vacuum packing, even using low-density polyethylene (LDPE) pouches with a high oxygen transmission rate (OTR), also reduced the formation of hexanal, which is a major off-flavor volatile, and thus should be recommended for the storage of Brazil nut kernels for the studied period. RESUMEN: Evolución en la formación de radicales lipídicos y pérdida de volátiles en nueces de Brasil empaquetadas al vacío y almacenadas a temperatura ambiente o refrigeradas.La nuez de Brasil es un producto importante de la región amazónica y su cadena productiva es fuente de ingresos para las comunidades locales. Se investigó por la primera vez el efecto de combinaciones de atmósferas de empaquetado (sueltas o empaquetadas al vacío) y temperaturas de almacenamiento (4 ± 1 °C o 24 ± 2 °C) sobre la evolución de la formación de radicales lipídicos y en los volátiles en nueces de Brasil. Se observó que la refrigeración, en combinación con envasado solo o al vacío, fue eficaz para reducir la formación de radicales lipídicos, como se detectó mediante espectroscopía de resonancia magnética de espín (ESR), así como de peróxidos, dienos conjugados y 3-octen-2-ona. Sin embargo, la combinación de refrigeración con envasado al vacío, incluso utilizando bolsas de polietileno de baja densidad (LDPE) con alta velocidad de transmisión de oxígeno (OTR), también redujo la formación de hexanal, que es un volátil de sabor desagradable, por lo que debería recomendarse para el almacenamiento de almendras de Brasil durante el período estudiado.ORCID ID: Sartori AGO https://orcid.org/0000-0002-6782-5379, Sampaio GR https://orcid.org/0000-0002-7763-4664, Bastos DHM https://orcid.org/0000-0002-9095-2843, Spoto MHF https://orcid.org/0000-0001-9219-6343, Skibsted LH https://orcid.org/0000-0003-1734-5016, Regitano-d'Arce MAB https://orcid.org/0000-0001-6801-6277Citation/Cómo citar este artículo: Sartori AGO, Sampaio GR, Bastos DHM, Spoto MHF, Skibsted LH, Regitanod'Arce MAB. 2018. Tendency of lipid radical formation and volatiles in lose or vacuum-packed Brazil nuts stored at room temperature or under refrigeration. Grasas Aceites 69 (4), e283. https://doi.