In the present study we aimed to examine the effect of glycine-Zn chelates (ZnGly) used in amounts corresponding to 0, 100, 50 or 25% of the requirement of this element on the fatty acids profile, antioxidative status, and dietetic value (atherogenic index (AI), thrombogenic index (TI), hypocholesterolemic/hypercholesterolemic ratio (h/H)) of breast muscles in broiler chickens. Two hundred 1-day-old Ross 308 male chicks were split into four equipotent experimental groups (assigned to 20 cages, 10 chicks in each, replicated five times): control, ZnGly-100, ZnGly-50 and ZnGly-25. The broilers received feed and water ad libitum. The experiment lasted 42 days. Significant differences in the content of respective fatty acids in the meat of chickens receiving ZnGly were observed in comparison to the control group; but they were not directional changes. A positive effect (P < 0.05) of Zn-Gly on certain indices of meat determined by the oxidoreductive status of the body or regulating such status was noted: superoxide dismutase, catalase and malondialdehyde. A significant effect of ZnGly on the dietetic value of broiler chickens’ breast meat was noted: the highest (P < 0.05) AI value was found in the ZnGly-50 and ZnGly-25 groups, and TI value in the ZnGly-25 group. The h/H relationship can be presented as ZnGly-25 < ZnGly-50 < ZnGly-100 < control group. To improve the dietetic value and to increase the oxidative stability of breast muscle meat, broiler chickens must receive ZnGly in an amount corresponding to more than 25% of the requirement of this element.

The paper aimed to analyse the safety of drinking coffee by adult Poles in terms of Pb and Cd content. The degree to which Cd and Pb passed from coffee grounds into the coffee infusion was also examined. Twenty-three samples of natural coffee were examined. The content of metals was determined using the ICP method. On average, dry coffee contained ca. 0.004 μg Cd and 0.05 μg Pb per 1 g, and 95.5% Cd and 94% Pb passed into the infusion. Drinking coffee supplies these metals in the amount of less than 2% TWI (tolerable weekly intake) for Cd and BMDL (benchmark dose lower confidence limit) for Pb. In the presented studies, the values of CDI (chronic daily intake), THQ (target hazard quotient) and HI (hazard index) indicators were lower than 1, which means that the risk of developing diseases connected with chronic exposure to Cd and Pb consumed with coffee must be evaluated as very low. The content of Cd and Pb in the analysed coffee infusions was very low, so drinking coffee does not pose a risk for consumers in terms of the content of these metals. However, it must be remembered that no threshold limits for toxic metal consumption exist because these metals accumulate in the body for a long time. The studies presented here also showed a low (r = 0.26) but still a positive correlation between the content of Pb in coffee and the degree (%) to which Pb passed into the infusion. This problem should be thoroughly investigated.

The studies aimed to evaluate the significance of cereal products as an essential source of Ca, Mg and K in the diets of Poles. The study covered 226 groups of cereal products most popular in Poland: bread, bread rolls, cooked pasta, cooked grains and cooked rice. The content of Ca, Mg and K was determined by means of FAAS. In addition, considering the recommended daily intake of K, Ca and Mg for the Polish population of adults, the percentage share of respective products in daily supply of these minerals was determined. The content of the above-mentioned minerals in all analysed cereal products can be presented as K > Mg > Ca. Intake of cereal products covers the requirement of K, Mg and Ca among adult Poles, respectively, in ca. 9%, ca. 12 (men)-15 (women) % and ca. 3%. The best source of K, Mg and Ca is bread which in the daily diets of Poles supplies more than 90% of minerals consumed with cereal products. It can be claimed that cereal products are a poor source of Ca, but they supply significant amounts of K and Mg in the diets of Poles, especially given that deficiency of such minerals is common in Poland. It would be important to consider obligatory fortification of flour with minerals which are deficient in the diets of Poles.