Control of the growth of Alicyclobacillus acidoterrestris in industrialized orange juice using rosemary essential oil and nisin.

The use of rosemary essential oil (RO) and its combination with nisin (RO+N) in preventing the multiplication of Alicyclobacillus acidoterrestris in orange juice was evaluated. The minimum inhibitory and bactericidal concentrations (MIC and MBC) for RO were both 125 µg ml-1 while RO+N displayed a synergistic effect. The use of RO and RO+N at concentrations of 1, 4 and 8× MIC in orange juice for 96 h was evaluated in terms of their sporicidal effectiveness. With regard to the action against A. acidoterrestris spores, RO at 8× MIC was sporostatic, whereas RO+N at 1× MIC was sporicidal. Morphological changes in the structure of the micro-organism after treatment were also observed by microscopy. Furthermore, flow cytometric analysis showed that most cells were damaged or killed after treatment. In general, the antioxidant activity after addition of RO+N decreased with time. The results demonstrate that using the combination of RO and nisin can prevent the A. acidoterrestris growth in orange juice.

Fusarium species and fumonisins associated with maize kernels produced in Rio Grande do Sul State for the 2008/09 and 2009/10 growing seasons

Ear rots caused by Fusarium spp. are among the main fungal diseases that contribute to poor quality and the contamination of maize grains with mycotoxins. This study aimed to determine the visual incidence of fungal-damaged kernels (FDKs), the incidence of two main Gibberella (a teleomorph of Fusarium) complexes (G. fujikuroi and G. zeae) associated with maize using a seed health blotter test, and the fumonisin levels, using high performance liquid chromatography, in samples of maize grains grown across 23 municipalities during the 2008/09 and 2009/10 growing seasons. Additionally, 104 strains that were representative of all of the analysed samples were identified to species using PCR assays. The mean FDK was seven per cent, and only six of the samples had levels greater than six per cent. Fusarium spp. of the G. fujikuroi complex were present in 96% of the samples, and G. zeae was present in 18% of the samples (5/27). The mean incidence of G. fujikuroi was 58%, and the incidence of G. zeae varied from 2 to 6%. FB1 was found in 58.6%, FB2 in 37.9%, and both toxins in 37.9% of the samples. The FB1 and FB2 levels were below the quantification limits for 41.3% of the samples, and the mean FB1 levels (0.66 µg/g) were higher than the mean FB2 levels (0.42 µg/g). The PCR identification separated the 104 isolates into three of the G. fujikuroi complex: F. verticillioides (76%), F. subglutinans (4%) and F. proliferatum (2%); and G. zeae (anamorph = F. graminearum) (18%). Our results confirmed the dominance of F. verticillioides, similar to other regions of Brazil, but they differed due to the relatively higher incidence of F. graminearum. Total fumonisin levels were below the maximum limit determined by current Brazilian regulations.

Estimates of maximum limits of food colours use in Brazil through the Danish Budget Method and the Bär and Würtzen-modified method.

The establishment of the permissible levels for the use of additives in foods must be based on the Acceptable Daily Intake (ADI). A method that may be applied for this purpose is the Danish Budget Method which estimates the maximum amount of the additive that may be added to the food based on the functional properties of the additive, and on the categories of the food in which the additive will be used. Based on the latest information Bär and Würtzen propose some modifications to the original Budget Method, one of which is the addition of a correction factor which takes into account the competition between different food additives with the same functional properties. In the present paper, both the Budget Method and the Bär and Würtzen-modified method were applied to evaluate whether the maximum levels of food colours use exceeded their ADI or not. Applying the original Budget Method, the results showed that the colours Sunset Yellow, Amaranth, Erythrosine, Ponceau 4R and Cochineal possibly exceeded the ADI; while applying the modified method only the colours Erythrosine and Cochineal would exceed the ADI. Brazilian regulatory authorities should be advised to establish maximum limits of use for the following categories of colours: Caramel, Inorganic, Natural and Artificial Colours Identical to the Natural Ones, where ADIs have been evaluated by JECFA.

Fumonisins B1 and B2 in Brazilian corn-based food products.

Eighty-one samples of corn products were acquired from markets and supermarkets in the city of Campinas, SP, Brazil, and were analysed for fumonsins B1 and B2 (FB1 and FB2). Forty samples (49%) were positive for FB1 (0.03-4.93 (micrograms/g) and 44 samples (54%) for FB2 (0.02-1.38 (micrograms/g). The samples, in order of decreasing contamination, were, corn meal (all contaminated, 0.56-4.93 (micrograms/g FB1), followed by degerminated corn (8/11 samples, nd-4.52 (micrograms/g FB1), corn flour (9/11 samples, nd-1.46 (micrograms/g FB1), precooked corn flour (4/6 samples, nd-1.79 (micrograms/g FB1), corn grits (2/2 samples, 0.17-1.23 (micrograms/g FB1), and popcorn (4/9 samples, nd-1.72 (micrograms/g FB1). Relatively lower incidences and levels of contamination were found in corn flakes (1/4 samples, nd-0.66 (microgram/g FB1) and corn flour baby cereal (1/2 samples, nd and 0.44 (microgram/g FB1). The samples of corn on the cob (common corn in the milky stage, 7 samples) and of the typical foods 'curau' (2 samples) and 'pamonha' (7 samples), both prepared with corn in the milky stage, did not show any detectable contamination. Canned sweet corn, also harvested in the milky stage, exhibited a very low incidence of and level of contamination (2/11 samples, nd-0.08 (microgram/g FB1). The intake of corn products is low in urban areas and in most rural areas in Brazil. In certain rural areas, however, corn products play a greater role in daily meals and the calculated intake of FB1 is higher than a proposed Tolerable Daily Intake of 800 ng/kg bw/day. This is the first report on fumonisins in Brazilian corn-based food products.