VALTER ARTHUR

VALTER ARTHUR

(Fonte: Lattes)

Resumo

Possui graduação em Biologia pela Universidade Metodista de Piracicaba (1977), mestrado em Energia Nuclear na Agricultura (Esalq) Universidade de São Paulo (1982) e doutorado em Agronomia (Entomologia) (Esalq) Universidade de São Paulo (1985). Atualmente é professor Associado no Centro de Energia Nuclear na Agricultura da Universidade de São Paulo. Tem experiência na área de Agronomia, com ênfase em Radioentomologia (tratamento quarentenário de pragas de importância agrícola) e Irradiação de alimentos (conservação e desinfecção de produtos agropecuários). (Texto extraído do Currículo Lattes em 27 dez. 2021)

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Natural coloring red beetroot under effects of gamma radiation
2021 - HARDER, MARCIA N.C.; FORMAGGIO, IAN H.; HARDER, LARISSA N.C.; BOVI, DEBORA C.M. de L.; ARTHUR, PAULA B.; ARTHUR, VALTER
As color is an important attribute related to the visual appeal and quality of food products, the reduction of pigment losses during food processing is a basic concern fr the industry. Based on this, the objective of this work was to evaluate the resistance of betalain from beet against the use of gamma radiation. Analyzes were carried out on pigments belonging to the betalain class on beets exposed to different doses of gamma radiation (Co60) using doses of 5, 10 and 15 kGy on beets, in addition to anon-irradiated sample for control. Color parameters were evaluated using the CIE L, a*, b * methodology, as well as the quantification of betalain in the samples. By of results the color parameters were affected in until 50% in relation the control. And the quantity betalain activity in the sample irradiated with doses of gamma radiation was more less 65% in relation the control. Therefore, it can be concluded that there is a potential resistance of the betalain pigment in the face of high doses of radiation, which returns interest to red beetroot dyes since most pigments are fragile to thermal treatments or with ionizing radiation.
Effects of gamma radiation in okra’s conservation
2021 - ARTHUR, PAULA B.; LEANDRO, RODRIGO S.R.; HARDER, LARISSA N.C.; HARDER, MARCIA N.C.; ARTHUR, VALTER
Okra is a very important vegetable in simple world cuisine. The aim of this work was to evaluate the effects of gamma radiation of Cobalt-60 in the conservation of okra (Abelmoschus esculentus). After 1 day of okras’s harvest, they were selected based in the size, presence of mechanical and phytophatologycal damages, and put in polystyrene trays and covered with thin polyethylene film. Then they were irradiated with doses of: 0 (control); 75; 100; 125; 150 and 200 Gy, at a dose rate of 0.259 kGy/h. The experiment was carried out in chamber regulated at 10o C of temperature and 80% of relative humidity. All analyses physical and chemical of the samples were carried out after 7 and 15 days of the storage. The results did not show any significative difference between the control and irradiated samples, except the viscosity that decreased with the increase of the dose of radiation. The dose of 75 Gy can be indicated to the conservation of okras because it was the one that showed best result in the coloration of okras.
Gamma radiation effects in precooked figs
2021 - HARDER, M.N.C.; HARDER, L.N.C.; LEANDRO, R.S.R.; ARTHUR, P.B.; ARTHUR, V.
Gamma radiation effects in jatoba flour
2021 - HARDER, M.N.C.; HARDER, L.N.C.; LEANDRO, R.S.R.; ARTHUR, P.B.; ARTHUR, V
Sterilizing of Alphitobius diaperinus (Panzer, 1797) (Coleoptera: Tenebrionidae) irradiated in pupa stage
2021 - ARTHUR, P.B.; VILLAVICENCIO, A.L.C.H.; HARDER, M.N.C.; MACHI, A.R.; LEANDRO, R.S.R.; ARTHUR, V.
The use of irradiation process in stored grain may be the solution for the losses caused in these products by insects, as it does not induce resistance in the insects and leaves no toxic residue, and is considered an efficient and safe method of control of insects. The aim of the experiment was to determine the sterilizing dose of ionizing radiation from cobalt-60 to Alphitobius diaperinus (Panzer, 1797) (Coleoptera: Tenebrionidae) in peanuts irradiated in pupa stage. The experiment was conducted in the laboratory of Radiobiology and Environment of the Center for Nuclear Energy in Agriculture - CENA / USP., Piracicaba, SP, Brazil. Peanuts samples infested with pupae of A. diaperinus were utilized in the experiment that consisted of 8 treatments with 5 repetitions. Each repetition consisted of 20 pupae a total of 100 individuals per treatment. Were irradiated with doses of 0 (control), 25, 50, 75, 100, 125, 150 and 175 Gy, in a source of cobalt-60, Gammacell-220 type, with a rate dose of 381Gy / h. The experiment was conducted in a controlled temperature of 25 ± 5 ° C and relative humidity of 70 ± 5%. After of irradiation process was evaluated of the number of emerged adult insects in each repetition in the treatments. The results showed that the sterilizing dose in F1 generation was 125 Gy and the pupa lethal dose 150 Gy. The dose of 150 Gy of gamma radiation can be used as phytosanitary treatment to control of immature stages of A. diaperinus infested peanuts.
Shelf-life of papaya nectar submitted to ionizing radiation
2021 - HARDER, M.N.C.; ANDRADE, T.; REIS, F.M.; FEITOSA, N.M.; PEREIRA, P.; ROBERTO, S.P.; NEME-OYAN, F.F.; HARDER, L.N.C.; OLIVEIRA, S.R.; ARTHUR, V.
A kind of drink consumption that has grown and appreciated for the most people is the nectar. The papaya nectar was recognized as a differentiated form of this fruit, with which the industry also gains in time of conservation, since the papaya is an extremely perishable fruit. The aim of this study was to evaluate gamma radiation as a way of conserving papaya nectar. The nectar was developed and subjected to gamma radiation at the dose of 1 kGy in a dose tax of 0.356 kGy.hour-1 and compared this treatment with the control group (0 kGy). According to the results obtained, it can be concluded that the dose used was adequate for the conservation of this product for the period evaluated reaching the aim.
Apple porridge submitted to gamma radiation for shelf-life extended
2021 - HARDER, M.N.C.; BREVIGLIERI, E.; OLIVEIRA, B.B.; ZAMBONI, K.; CARVALHO, S.; NEME-OYAN, F.F.; HARDER, L.N.C.; OLIVEIRA, S.R.; ARTHUR, V.
Among many apple products, apple porridge is a popular product nowadays. It is a practical, healthy and tasty product that can be consumed throughout the day. However, it is an extremely perishable product. Therefore, the aim of this work was to evaluate the shelf-life period of apple porridge after the application of gamma radiation as a conservation technology. After the formulation of apple porridge was developed, which was subjected to gamma radiation at the dose of 1kGy in a dose tax of 0.356 kGy.hour-1 and compared this treatment with the control group (0kGy). From the results presented, it can be concluded that the conservation period of apple porridge submitted to gamma radiation is 60 days. From the 90th day, the samples showed microbial growth, becoming not accepted for consumption. In comparison to the control group, the use of gamma radiation was promising, since the standard sample showed contamination before 30 days. By the results it can be concluded that the dose used was adequate for the conservation of this product for the period evaluated.