Limited survey for the presence of aflatoxins in foods from local markets and supermarkets in Valencia, Spain

Aflatoxin B1 (AFB1), B2 (AFB2), G1 (AFG1) and G2 (AFG2) were extracted by matrix solid-phase dispersion with C18 silica and acetonitrile as the eluting solvent, analysed by liquid chromatography with fluorescence detection and confirmed by liquid chromatography with mass spectrometry using an electrospray interface in 58 samples grouped as cereals, dried fruits, herbs and spices, pulses, snacks, and nuts and nut products collected from local markets and supermarkets in Valencia, Spain. All samples analysed by the proposed method were previously studied with an enzyme-linked immunosorbent assay as a screening protocol for the fast detection of mycotoxins. The samples containing residues (3/58) were hazelnut (0.42 and 0.52 μg kg^-1 for AFB1 and AFG1, respectively), nut cocktail (0.29 and 0.47 μg kg^-1 for AFB1 and AFG1, respectively) and pinhol (0.30 μg kg^-1 for AFG1). Such values were below the legislated maximum residue levels for the European Union.     

Effect of extrusion conditions on iron stability and physical and textural properties of corn snacks enriched with soybean ferritin

Soybean sprouts cultured in 20 mm FeSO₄ were introduced into corn snacks (1.75–3.50%) to supplement iron. The effect of extrusion process on the ferritin iron stability and on product quality was studied. Iron stability in these fortified snacks depended mainly on feed moisture levels, with the best results seen when the feed moisture and temperature were 12% and 110 °C, respectively. Lower feed moisture was beneficial to hardness, expansion ratio and bulk density, while lower temperature increased snack hardness and density, while worsening the expansion ratio. The snacks’ water absorption was strongly and directly dependent on the temperature, while their solubility mainly depended inversely on feed moisture. All of the variables tested altered the colour of the snacks. The conditions that were best for producing the ferritin‐fortified snacks – 12% feed moisture, and temperature equal than or less to 140 °C – may yield a product with the desired quality features.     

武汉面点小吃的地方特色

我国在主食上形成了“南米北面”的格局。武汉受区域位置的影响,其面点小吃在选料上呈现出米面结合的特色。特殊的地理环境使武汉的饮食物产极其丰富,人们在长期的饮食生活中形成了软糯鲜香的口味审美特征。并由于武汉的饮食物产、武汉人的饮食追求以及各地的文化交融,形成了武汉面点小吃以酵面、米浆、肉糖制馅、蒸炸为主的工艺特色。     

Commercial processed food may have endocrine-disrupting potential: soy-based ingredients making the difference

Processed and packaged food items as well as ready-to-eat snacks are neglected and poorly characterised sources of human exposure to endocrine-disrupting chemicals (EDCs). In this study we investigated the presence of xenoestrogens in commercially processed and packaged Finnish foods, arising from substances deliberately added or inadvertently contaminating the food, substances formed as a result of food processing, or substances leaching from food packaging materials. Samples were obtained in three separate batches of equivalent products from both a supermarket and a local representative of a global chain of hamburger restaurants and extracted by a solid-phase extraction method. Their endocrine-disrupting potential was determined by yeast bioluminescent assay, using two recombinant yeast strains Saccharomyces cerevisiae BMAEREluc/ERα and S. cerevisiae BMA64/luc. In this test system, the majority of samples (both foodstuffs and wrappers) analysed proved negative. However, all batches of industrially prepared hamburgers (but not those obtained from a hamburger restaurant) as well as pepper salami significantly induced luciferase activity in the BMAEREluc/ERα yeast strain indicating the presence of xenoestrogens, with estradiol equivalents of these products ranging from 0.2 to 443 pg g^–1. All three products contained soy-based ingredients, which apparently accounted for, or at least contributed to, their high estrogenic activity, since no signal in the assay was observed with extracts of the packaging material, while two different soy sauces tested yielded an intense signal (28 and 54 pg ml^–1 estradiol-equivalent). These findings imply that by and large chemicals arising in the processing or packaging of foodstuffs in Finland constitute an insignificant source of xenoestrogens to consumers. However, soy-derived ingredients in certain food items might render the entire products highly estrogenic. The estrogenic activity of soy is attributed to isoflavones whose health effects – though widely considered beneficial – are controversial. As hamburgers are a popular type of food among children, the findings are noteworthy and possibly of concern.     

Mitigation measures for acrylamide reduction in dough-based potato snacks during their expansion by frying

ABSTRACT

Acrylamide (AA) can occur in fried and baked food products which contain reducing sugars and free asparagine. Recently, the European Commission established mitigation measures and benchmark levels for the reduction of AA in food. The content of reducing sugars in raw materials and the temperature and time of the expansion process by frying were considered in this study of the preparation of dough-based potato snacks, mainly destined for children. Final moisture and bulk density were also evaluated. An increase from 0.15 to 1.0% in reducing sugar content, due to the addition of micro-ingredients in the dough, caused a remarkable AA increase of five- to six-fold. During frying at temperatures between 175 and 195°C, AA was produced after only a few seconds; the AA content was affected more by process time than by temperature. The best temperature/time conditions for expansion by frying were 185°C for 8 s.     

The physico-chemical characteristics of extruded snacks enriched with tomato lycopene

Adding tomato derivatives to traditional starchy extruded snacks can improve their nutritional properties by adding lycopene and fibre; however the physico-chemical properties of these products must also be considered. Ingredients and extrusion parameters, including temperature, alter these properties, but their effect on lycopene content is not known. In this study, crisp low density extruded snacks were manufactured from corn, wheat and rice, with or without dried tomato skin or paste powder extruded at temperatures of 140, 160 or 180 °C. Lycopene content and the physico-chemical properties (expansion, density, hardness, colour parameters and percentage of moisture loss) of the extruded products were measured. Lycopene retention was higher in products containing tomato skin powder and significantly lower when wheat flour was used to make the snacks. Increases in the processing temperature improved the physico-chemical characteristics of the snacks but had no significant effect on lycopene retention (P > 0.05).     

Co‐extrusion of pearl millet‐whey protein concentrate for expanded snacks

A study was conducted to develop pearl millet‐based extruded snacks with whey protein concentrate (WPC) to enhance its acceptability and nutritional value. Pearl millet grits (841 μ) was extruded with different levels (0%, 2.5%, 5.0% and 7.5%) of WPC at constant feed rate (10.5 kg h^?1) and moisture content (14%). Addition of whey protein at 7.5% level significantly (P ≤ 0.05) increased T_g from 75.1 ± 0.26 °C to 120.5 ± 1.28 °C and T_m from 89.1 ± 1.51 °C to 158.7 ± 1.37 °C, which resulted in less expanded and harder extrudates. The expansion index of extrudates was negatively correlated (P ≤ 0.05) with protein (r = ?0.940), bulk density (r = ?0.949), hardness (r = ?0.971) and breaking strength (r = ?0.921), while positively correlated (P ≤ 0.05) with overall acceptability (OAA; r = 0.988). Keeping in view the nutritional, textural and consumer's acceptability, incorporation of 5% WPC in pearl millet grits (841 μ) was recommended for preparation of acceptable expanded snacks.     

Studies on deep-fat fried snacks from some cereals and legumes

Deep-fat fried products, prepared from cereals, legumes and their blends, are universally popular due to their desirable organoleptic profile. Grain types differ in their chemical make-up and physicochemical properties, which may account for the differences in the oil content of the snacks. In addition, the frying medium also plays an important role in the oil pick-up during deep-fat frying. This work attempts to correlate these parameters with the oil content in a traditional Indian extruded and deep-fat fried product, sev, using flours from rice, wheat, amaranth, chickpea, cowpea, black gram and green gram. No correlation between the proximate constituents (water-holding capacity and oil-holding capacity) and the oil content of the fried sev was seen. Oil content in sev was minimum when fried in cottonseed oil. © 1998 SCI.