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The fate of AFM1 during production of a long maturing cheese (Parmesan cheese) was assessed. Different levels of AFM1 contamination and of the fat/casein (F/C) ratio of milk were considered, in order to evaluate if these factors can influence the enrichment factor (EF) of AFM1 in cheese. For this purpose, 24 cheese-makings were carried out using naturally contaminated milk at 3 different AFM1 levels and at 2 F/ C ratios. AFM1 analysis was performed by HPLC in raw milk, cream, cauldron milk, liquid cattle rennet, whey, curd and cheese at 3, 9, 16 and 24 months of ageing. The mass balances of the cheese-making processes were close to 100%; in whey, AFM1 concentration was about 40% less than the concentration in cauldron milk. The EF in curd was between 4.0 and 5.2, with an average value of 4.7 ± 0.4; this factor was not significantly affected by either AFM1 contamination level or F/C ratio. During maturation, AFM1 concentration and consequently EF increased from curd to 16 ageing months; successively, AFM1 slightly decreased at 24 months and consequently the EF. At 3, 9, 16 months of maturation, the EF was significantly higher for cheeses prepared using milk with low F/C than those with high F/C milk; on the contrary, EF was not significantly influenced by the AFM1 contamination level. In cheeses, EF values were between 4.7 and 6.3; from these results, the maximum admissible level for AFM1 in Parmesan cheese should be about 0.275 mg kg1.

Objective Lysozyme is an enzyme that hydrolyzes bacterial peptidoglicans and for this reason is used in cheese manufacturing in order to prevent a defect of long-ripened hard cheese called “late blowing”, due to the outgrowth of spores of Cl. tyrobutyricum and Cl. butyricum. Moreover, germination of L. monocytogenes spores into vegetative cells is also sensitive to lysozyme. Lysozyme can be an allergenic molecule and for this reason there are concerns about its use in food industry. The immunological and clinical response of consumption of lysozyme containing cheese, has been evaluated in 25 egg-sensitive subjects with or without lysozyme sensitization. Methods Twenty-five egg-sensitive subjects were enrolled in this study. All the subjects were already treated for egg-sensitization and presented positive Skin Prick Test. All the subjects had a BMI ≤ 25 kg/m2 and were in the range of 20-50 years. Each subject was studied twice and received randomly 30 gr of Grana Padano (containing lysozyme) or TrentinGrana cheese (lysozyme-free) of two different aging periods: 16 or 24 months. A wash-out period of 1 week between each cheese intake was adopted. Blood samples were taken in fasting conditions and 1 hour after cheese intake and Ig A, total Ig E and lysozyme, ovomucoid and ovalbumin-specific Ig E measured. Results No adverse reactions were observed in both groups of patients after cheese samples were given. Lysozyme did not determine any variation of specific Ig E compared with basal level. In lysozyme sensitive patients a significant relationship between Ig A and lysozyme specific Ig E was observed when lysozyme-containing cheese was given, confirming that lysozyme can pass the gut barrier. Conclusions Neither adverse events nor immunological responses were observed after ingestion of cheese containing lysozyme. However, the immunological properties of peptides deriving from cheese protein hydrolysis need to be clarified as well as the effect of lysozyme on bacterial p

Purpose Lysozyme, obtained from egg white, is a potential food allergen used in the dairy industry to prevent late blowing of the loaf caused by the outgrowth of clostridial spores (Cl. butyricum and Cl. tyrobutyricum) during cheese aging. The aim of this study was to evaluate the possible correlation between egg protein allergy in paediatric age and sensitization to egg lysozyme, used for the preparation of Grana Padano cheese. Methods The tolerability of Grana Padano cheese has been evaluated in paediatric patients allergic to egg proteins through an oral provocation test with increasing amounts of cheese containing, or not, lysozyme at 12 months and 24 months of aging. Results When lysozyme sensitized children received 12-months aged and lysozyme-containing cheese, several immediate and late adverse reactions such as itching, abdominal pain, vomiting, nausea, dermatitis, rhinitis, bronchial asthma, urticaria, angioedema, were seen in 5 out of 21 subjects; only 1 out of 21 children showed an adverse reaction after challenge with 24-months ripened lysozyme-containing cheese. Conclusions There is a possible relationship between the severity of allergic reactions and the lysozyme-specific IgE level in blood. In particular vomiting, hypotension and abdominal pain were present when IgE level was higher than 7 kU/L. A ripening time of 24 months may reduce allergy problems when lysozyme-containing cheese is given to sensitized subjects, probably due to the hydrolysis of antigenic epitopes during aging.

A study was conducted to evaluate the excretion pattern of melamine from feed into eggs, plasma, kidney, liver and muscle of laying hens. In particular, 90 laying hens were randomly allocated to three dietary treatments and fed diets contaminated with melamine at a level of 2.5, 25 and 250 mg of melamine/kg of diet for T1, T2 and T3 groups, respectively. The diets were offered in six replicate boxes (five hens each) for 13 days. Eggs were collected from each group for melamine quantification on days 0, 1, 3, 6, 9 and 13. At the end of the experimental period, one hen per box was randomly selected and slaughtered to collect plasma, liver, kidney and muscle samples. During the experiment, feeding diets with increasing levels of melamine had no effect ( P.0.05) on weight gain, feed intake, egg production, egg weight and mortality of laying hens. The melamine in eggs increased from day 1 after melamine ingestion and reached a plateau between days 6 and 13 of melamine ingestion. At steady-state condition, the melamine egg concentrations increased ( P,0.01) with treatments, being 0.026, 0.352 and 4.631 mg/kg for T1, T2 and T3, respectively. Similarly, the carryover of melamine from feed to egg increased ( P,0.05) with the levels of melamine in the diets, varying from 0.50 to 0.70 and 0.84 for T1, T2 and T3, respectively. The melamine was detected in plasma of all tested groups, increasing ( P,0.01) with levels of melamine in the diets (0.030, 0.266 and 4.102 mg/l in T1, T2 and T3, respectively). Melamine was not detected in kidney, liver and muscle of hens fed T1. Except for kidney sampled in the T3, no melamine concentration higher than 2.5 mg/kg, representing the maximum allowable limit set by the US Food and Drug Administration and European Union for food and feeds, was measured. The melamine resulted higher in plasma and kidneys than in the liver and muscle both in T2 and T3. The results confirmed the presence of an excretion pattern of melamine from feed to eggs and

Objectives High Ca content is one of the most important characteristic of dairy products, According to some Authors dairy products have a better Ca digestibility compared to plant foods and this characteristic has been related to the inclusion of Ca in the caseinophosphopeptides (CPP). Because ripening time and lysozyme can affect peptide pattern we decided to study the effect of these two factors on in vitro Ca digestibility. Experimental methods 20 samples of Grana Padano produced with lysozyme and 17 samples produced without lysozyme (total 37 samples), aged between 11 and 25 months were obtained from 2 different cheese-factories. In vitro Ca digestibility (dCa) was determined using the methods of Perales et al (J Agric Food Chem, 2005, 53: 3721). Molecular weight (MW) of peptides was determined by exclusion chromatography and CPP were determined by HPLC-MS. Analysis of variance was carried out with SAS 9.1 using GLM procedure of the SAS 9.1. The correlation between variables was performed with the PROC CORR of SAS 9.1. Results The dCa (%) at ripening time of 12, 15-20 and > 20 months were: 71.75, 76.10, 86.04 for Grana Padano and 73.21, 63.70, 62.59 for lysozyme-free cheese. In Grana Padano dCa and aging were positively related (r2 = 0.27; P<0.05). Since Ca is almost entirely associated with caseins, the difference in dCa could be due to a different proteolysis mediated by the presence of lysozyme as reported by Sforza et al. (Eur J Mass Spectrom, 2004, 10: 421). In the range of MW from 1000 to 2500 D, we observed an higher number of Ca-binding sequences in lysozyme containing cheese compared to Trentin Grana and this fact could explain the different result. Furthermore dCa in lysozyme containing cheese was positively correlated to the concentration of peptides having MW in the range 1000-1500 D and 1500-2500 D. Conclusions A larger number of cheese samples is necessary in order to better describe the effect of ripening and lysozyme addition on Ca digestibility

The aim of this study was to assess Ca digestibility using in vitro and in vivo methodology (rats). The tested foods were: cheese (Grana Padano; Emmentaler), soybean-based products (tofu; burger; milk; yogurt), and legumes (peas; beans). Ca digestibility was found to be high in Emmentaler (84.3%), Grana Padano (83.6%) and tofu (80.3%), with significantly lower values for soya burgers (64.1%) and soya milk (60.6%). The lowest values were detected in peas (49.6%) and beans (31.4%). Poor correlation was found between in vivo and in vitro data. The current RDAs have been established on the basis of 30% Ca digestibility, a value which reduces the risk of calcium deficiency but underestimates the contribution of dairy products. The adoption of specific, instead of general, digestibility values for each food might improve the accuracy of dietary formulations. This will require considerable efforts to develop simple and reliable in vitro methods to assess foods.

The objective of this study was to compare the effect of Bt corn and isogenic corn on the growth of weaned piglets. One hundred and twenty-eight weaned piglets weighing 8.8 ±1.27 kg live weight were randomly assigned to 4 groups of 32 animals each (16 castrated males and 16 females). Bt corn (line MON810) and isogenic corn were produced at two farms located in the provinces of Lodi and Venice (northern Italy). The Bt corn had the same chemical composition as the isogenic corn but a lower content of fumonisin B1 (FB1). The experimental period (35 days) was in two phases: 0-14 d and 15-35 d. There was no significant difference in average daily gain (ADG) among groups during the first feeding phase. Compared to animals fed isogenic corn, the piglets fed Bt maize gained more weight during the second feeding phase (Bt: 464.1 g/d, isogenic: 429.1 g/d; P < 0.05). Also, the ADG over the entire trial was higher in piglets fed Bt corn versus piglets fed isogenic corn (Bt: 396.4 g/d, isogenic: 374.1 g/d; P < 0.05). The ADG of the whole period decreased linearly (P <0.05) with respect to the FB1 content of the diet. Final weight was higher in piglets fed the diet containing Bt corn (Bt: 22.68 kg, isogenic: 21.83 kg; P < 0.05). No differences in feed intake and in the feed:gain ratio were observed, although a linear response between FB1 and feed:gain ratio in first 14 days of the experiment was detected.

The potential of anaflatoxin B1 (AnAFB1) conjugated to keyhole limpet hemocyanin (KLH) as a vaccine (AnAFB1-KLH) in controlling the carry over of the aflatoxin B1 (AFB1) metabolite aflatoxin M1 (AFM1) in cow milk is reported. AFB1 is the most carcinogenic compound in food and foodstuffs amongst aflatoxins (AFs). AnAFB1 is AFB1 chemically modified as AFB1-1(Ocarboxymethyl) oxime. In comparison to AFB1, AnAFB1 has proven to be non-toxic in vitro to human hepatocarcinoma cells and non mutagenic to Salmonella typhimurium strains. AnAFB1-KLH was used for immunization of cows proving to induce a long lasting titer of anti-AFB1 IgG antibodies (Abs) which were cross reactive with AFB1, AFG1, and AFG2. The elicited anti- AFB1 Abs were able to hinder the secretion of AFM1 into the milk of cows continuously fed with AFB1. Vaccination of lactating animals with conjugated AnAFB1 may represent a solution to the public hazard constituted by milk and cheese contaminated

A total of 52 Italian and French commercial cheeses were analysed for fatty acid composition and conjugated linoleic acid (CLA) concentration. The cheeses were first grouped according to the ruminant species of the milk used inmanufacturing, then according to the following criteria: (1) cheeses obtained from milk of the same ruminant species but using different production technologies; (2) cheeses produced from milk of different ruminant species but through similar cheesemaking processes. Comparative studies of fatty acid composition and CLA levels in the different cheese classes were carried out. In our study, the arrangement of the ruminant species according to the increasing CLA concentration in cheese was: goat = cow < sheep. Sheep cheeses had the highest levels of CLA (9.86 mg/g fat), a-linolenic acid (0.75%) and trans-vaccenic acid (1.63%), and the lowest contents of linoleic acid (1.80%) and oleic acid (16.83%). The comparison of cheeses obtained from milk of the same ruminant species but through different production technologies reported statistically significant differences in the fatty acid profiles that could be due to a different degree of lipolysis in the cheeses compared. Nevertheless, statistically significant differences in CLA concentration were not found; this suggests that the factors involved in the cheesemaking process generally do not affect the CLA content in milk fat.

Iodine and selenium are essential trace elements involved in the regulation of thyroid metabolism and antioxidant status. Two experiments were undertaken on lactating cows to determine the milk concentrations of iodine and selenium, carry over (CO) in milk, the fraction in curdle portion and how milk yield affects the milk iodine and selenium concentrations and CO. Sources of elements were potassium iodide and sodium selenite. In Experiment 1, 12 cows were randomly allotted to three diet groups in a completely randomized design: control group (CTR) - total mixed ration (TMR) containing 1.71 and 0.08 mg/kg dry matter (DM),Group 1 (T1) - TMR plus 23.8 and 2.2 mg; Group 2 (T2) - TMR plus 45.5 and 4.3 mg, respectively, for iodine and selenium. In Experiment 2, 30 cows were allotted to three groups according to milk yield: high (H), average (A) and low (L). Within each group, cows were randomly assigned two levels of iodine and selenium: Level 1: TMR containing 1.55 and 0.15 mg/kg DM; Level 2: TMR plus 47.2 mg and 8.0 mg, respectively, iodine and selenium. In both experiments, individual milk samples were collected and analyzed for iodine and selenium contents. In Experiment 1, Grana Padano cheese was obtained at lab scale and the iodine and selenium fractions in the curd were measured. In Experiment 1, the iodine intake increased (P < 0.001) the concentration and total excretion in milk. The CO increased (P < 0.05) from 16 (CTR) to 27 (T1) and 26% (T2); the sampling time was significant (P < 0.05) with no interaction with treatments. Concentration of selenium in milk was increased (P < 0.05) by treatment and CO decreased (P < 0.01) from 26 (CTR) to 12 (T1) and 9% (T2). The iodine showed a mild enrichment factor in the curdle (about 1.7-fold), whereas selenium enriched five- to sevenfold. In Experiment Z the level of iodine supplementation affected (P < 0.05) the concentration and total excretion in milk. No effects on milk iodine concentration were related to milk yield

Antisecretory factor (AF) is an endogenous protein that has shown to be a potent inhibitor of intestinal fluid secretion and inflammation. AF content in sows' milk is important for protection against neonatal diarrhoea in suckling piglets. Feeding specific hydrothermally processed cereals (HPC) has proven to increase the plasma level of AF and to be helpful in counteracting diarrhoea in domestic animals. The aim of the study was to investigate the effects of an AF-inducing diet on piglets' growth performance and intestinal mucosa

Six pregnant heifers, coming from a herd with a history of high concentration of Polychlorobifenyls (PCB) into the milk, were fed with a very low-PCB diet starting from the 6th month of pregnancy. After parturition cows were milked for at least 190 d with a maximum of 270 d. Diet was made of: corn silage (31.7% of DMI), dehydrated alfalfa (13.3% of DMI), grass hay (3.7% of DMI) and concentrate (51.3% of DMI). The average DMI was 23.12 kg/d. Milk production was recorded and samples of milk and blood were taken and analyzed for PCB (18, 28, 31, 52, 44, 101, 149, 118, 153, 138, 180 and 194 congeners) content using a GC-MS technique. The average milk yield (kg/d) of the 6 cows was 26.0, 22.5, 23.2, 24.5, 28.9, 29.3. The maximum PCB concentration of 100 ng/g of fat allowed by the Italian law was reached after 144-209 days of lactation. One animal after 204 days had a PCB concentration of 102 ng/g fat. If log(10) of PCB concentration (ppb) in milk fat is regressed against days in milking (DIM) the following significant equation was obtained: log(10) PCB (ng/g of milk fat)= 2.796 -0.00474 DIM; r(2) 0.72; P<0.01 The initial level of contamination is not the main factor affecting the time required in order for PCB to return to below the legal threshold of 100 ng/g fat, while daily milk yield significantly affects PCB excretion. Body condition and energy balance could be important factors affecting PCB excretion. In the presence of high contamination, about 6 months of lactation are required in order to obtain milk with a sufficiently low PCB content. Among the seven congeners considered by Italian legislation, PCB 101, PCB 118, PCB 138, PCB 153 constitute almost all the PCBs found in tissues and milk, with a much smaller presence of PCB 180, and the numbers of the congeners PCB 28 and PCB 52 are almost insignificant, probably because they accumulate little in the body. The congeners PCB 138 and PCB 153 are those most frequently found. For PCB 138 the liver is the principa

Bioavailability of methionine (Met) of three commercial supplements was assessed in three lactating dairy cows by a standardized blood plasma test. A spot dose of rumen-protected D,L-Met (SmartamineMTM or SM; 65.4 g/cow/day), Met hydroxy analog (Alimet® or AL; 57.5 g/cow/day) and its isopropyl ester (MetaSmart or MT; 88.5 g/cow/day) were fed daily (9:00h) by oral bolus, providing 50 g/cow/day of D,L-Met, to 3 cows in a Latin square design. Blood samples were obtained by jugular venipunctures the day before (day 0) and five days after (day 5) the treatment at 9:30h, 13:00h and 17:00h and plasma was harvested. On day 0, the Met concentration was similar among treatments. At day 5, the plasma Met was increased with a different response (P<0.05) among treatments: +285.8% for SM (89.67 at day 5 versus 23.79 μmol/L at day 0), +167.2% (55.62 versus 21.60 μmol/L, respectively) for MT and +50.9% for AL (35.07 versus 23.19 μmol/L, respectively).

CLA levels and fatty acid composition were measured to compare the fat composition in organic bulk milk, destined to the production of Grana Padano cheese, with those produced by conventional system. All analysed organic samples were characterized by higher annual means of CLA, vaccenic acid (TVA) and linolenic acid (LNA) in comparison with conventional samples (with P<005). Nevertheless, no particular effect of the production technology was seen on the CLA content. The animal diet appears to be the factor which has the highest effect on the CLA concentration in milk and milk products and an organic diet based on fresh or dried forage, that is rich in CLA precursory fatty acids, may improve the yield of fatty acids with beneficial effects on health.

According to general consensus, the global climate is changing, which may also affect agricultural and livestock production. The potential impact of climate change on food security is a widely debated and investigated issue. Nonetheless, the specific impact on safety of food and feed for consumers has remained a less studied topic. This review therefore identifies the various food safety issues that are likely to be affected by changes in climate, particularly in Europe. Amongst the issues identified are mycotoxins formed on plant products in the field or during storage; residues of pesticides in plant products affected by changes in pest pressure; trace elements and/or heavy metals in plant products depending on changes in their abundance and availability in soils; polycyclic aromatic hydrocarbons in foods following changes in long-range atmospheric transport and deposition into the environment; marine biotoxins in seafood following production of phycotoxins by harmful algal blooms; and the presence of pathogenic bacteria in foods following more frequent extreme weather conditions, such as flooding and heat waves. Research topics that are amenable to further research are highlighted.

In an in vitro experiment, aluminosilicates (Atox (R) and Novasil (TM) Plus) and a yeast cell wall derivate (Mycosorb (R)) were used as sequestering agents (SAs) to verify their capacity for binding aflatoxin B I (AFB1) in vitro. SAs were individually mixed at three different ratios with AFB1 (1:5000. 1:50,000 and 1:500,000, w/w) in water (CTR), rumen fluid from a lactating cow with a low rumen pH (LRS) or rumen fluid from a dry cow with a high rumen pH (HRS), and then used in a 3 x 3 x 3 factorial arrangement of a completely randomized design. At the 1:500,000 ARSA ratio Atox (R) and Novasil (TM) Plus sequestered over 0.87 and 0.98 of the AFB1 in the CTR and rumen solutions (LRS and HRS), respectively. This efficacy decreased when the amount of clays was reduced, with higher values (P<0.001) for Atox (R) compared with Novasil (TM) Plus (0.50 vs. 0.28 in CTR; 0.58 vs. 0.16 in LRS and 0.44 vs. 0.27 in HRS). Mycosorb (R) had a lower sequestering efficacy (P<0.001) in all of tested experimental conditions, with 0.34 being the maximum value obtained in the CTR solution. In a parallel in vivo experiment, complexes between AFB1 and SAs (ARSA) were obtained by mixing one litre of AFB1 contaminant solutions (0.845, 0.790, 0.832 and 0.911 mu g/mL) with 50 g Atox (R), 150 g Mycosorb (R), 50 g Novasil (TM) Plus and 4000 mL rumen fluid, respectively. The unbound AFB1 was eliminated from the ARSA complexes after centrifugation and washing of the precipitates. The strengths of the complexes were investigated in vivo by measuring both the aflatoxin M1 (AFM1) levels and the AFB1 recovery rate (RR) in milk from cows administered through the esophagus, before the morning meal, 300 mL/cow of the prepared ARSA complex suspension for a total of 0.447, 0.360. 0.460 and 0.367 mu g/mL AFB1, respectively for Atox (R), Mycosorb (R), Novasil (TM) plus and contaminated rumen fluid (R-SA). When the prepared ARSA complexes were given to cows, differences (P<0.05) were observed for the total excr

Aflatoxin M1 (AFM1) residues in milk are regulated in many parts of the world and can cost dairy farmers significantly due to lost milk sales. Additionally, due to the carcinogenicity of this compound contaminated milk can be a major public health concern. Thirty-four lactating dairy cows were utilised to investigate the relationship between somatic cell counts (SCC), milk yield and conversion of dietary aflatoxin B1 (AFB1) into milk AFM1 (carryover (CO)). The AFM1 in milk increased as soon as the first milking after animal ingestion with a pattern of increment up to the observed plateau (between 7th and 12th days of AFB1 ingestion). There was a significant (P,0.01) effect of the milk yield whereas no effect could be attributed to the SCC levels or to the milk yield3SCC interaction. Similarly, the main effect of milk yield was also observed (P,0.01) on the total amount of AFM1 excreted during the ingestion period. Although the plasma concentration of gamma-glutamyl transferase was significantly affected by aflatoxin administration, levels of this liver enzyme were within the normal range for lactating dairy cows. The current data suggest that milk yield is the major factor affecting the total excretion of AFM1