Levels of nitrate, nitrite and nitrosamines in model sausages during heat treatment and in vitro digestion - The impact of adding nitrite and spinach (Spinacia oleracea L.)

Nitrite derivatives react with endogenous precursors forming N-nitrosamines associated with development of colorectal cancer. The present study aims to investigate the formation of N-nitrosamines in sausage during processing and in vitro gastrointestinal digestion after adding sodium nitrite and/or spinach emulsion. The INFOGEST digestion protocol was used to simulate the oral, gastric, and small intestinal phases of digestion, and sodium nitrite was added in the oral phase to mimic the input of nitrite from saliva as it has shown to affect the endogenous formation of N-nitrosamines. The results show that the addition of spinach emulsion, in spite of it being a source of nitrate, did not affect the nitrite content in either batter, sausage, or roasted sausage. The levels of N-nitrosamines increased with the added amount of sodium nitrite, and further formation of some volatile N-nitrosamines was observed during roasting and in vitro digestion. In general, N-nitrosamine levels in the intestinal phase followed the same trend as in the undigested products. The results further indicate that nitrite present in saliva may cause a significant increase in N-nitrosamine levels in the gastrointestinal tract and that bioactive components in spinach may protect against the formation of volatile N-nitrosamines both during roasting and digestion.

Meat consumption and consumer attitudes - A Norwegian perspective

Norway has lower meat consumption than other North European countries. Meat is acknowledged as important for food security in Norway, as Norway's agricultural possibilities are best suited for free-ranging and self-foraging animals. Meat has a strong position in the Norwegian diet, particularly as a centrepiece for special occasions. Good taste, product variety, and affordable price make meat a convenient choice. Norwegian consumers are not worried about animal welfare in local production, nor highly driven by environmental motives for reducing their consumption. Meat analogues have a very small market share, and taste and processing level do not make it a primary replacement for meat reducers. Still, Norwegian consumers' attitudes towards meat have become more diverse in later years. More consumer segments display meat-reducing behaviours citing both health and sustainability reasons. Females are particularly interested in reducing meat consumption, young age and urban lifestyle are other characteristics of meat reducing segments.

Formation of Malondialdehyde, 4-Hydroxynonenal, and 4-Hydroxyhexenal during in Vitro Digestion of Cooked Beef, Pork, Chicken, and Salmon

Red meat high in heme iron may promote the formation of potentially genotoxic aldehydes during lipid peroxidation in the gastrointestinal tract. In this study, the formation of malondialdehyde (MDA) equivalents measured by the thiobarbituric acid reactive substances (TBARS) method was determined during in vitro digestion of cooked red meat (beef and pork), as well as white meat (chicken) and fish (salmon), whereas analysis of 4-hydroxyhexenal (HHE) and 4-hydroxynonenal (HNE) was performed during in vitro digestion of cooked beef and salmon. Comparing products with similar fat contents indicated that the amount of unsaturated fat and not total iron content was the dominating factor influencing the formation of aldehydes. It was also shown that increasing fat content in beef products caused increasing concentrations of MDA equivalents. The highest levels, however, were found in minced beef with added fish oil high in unsaturated fat. This study indicates that when ingested alone, red meat products low in unsaturated fat and low in total fat content contribute to relatively low levels of potentially genotoxic aldehydes in the gastrointestinal tract.

Chicken meat nutritional value when feeding red palm oil, palm oil or rendered animal fat in combinations with linseed oil, rapeseed oil and two levels of selenium

Chicken meat nutritional value with regard to fatty acid composition and selenium content depends on the choice of dietary oil and selenium level used in the chickens' feed. The objective of this study was to investigate the effect of replacing commonly used rendered animal fat as a dietary source of saturated fatty acids and soybean oil as a source of unsaturated fatty acids, with palm oil and red palm oil in combinations with rapeseed oil, linseed oil and two levels of selenium enriched yeast on chicken breast meat nutritional value. The study also wished to see whether red palm oil had a cholesterol lowering effect on chicken plasma.204 male, newly hatched broiler chickens were randomly divided into twelve dietary treatment groups, and individually fed one out of six dietary fat combinations combined with either low (0.1 mg Se /kg feed) or high (1 mg Se/kg feed) dietary selenium levels. Linseed oil, independent of accompanying dietary fat source, lead to increased levels of the n-3 EPA, DPA and DHA and reduced levels of the n-6 arachidonic acid (AA). The ratio between AA/EPA was reduced from 19/1 in the soybean oil dietary groups to 1.7/1 in the linseed oil dietary groups. Dietary red palm oil reduced total chicken plasma cholesterol levels. There were no differences between the dietary groups with regard to measured meat antioxidant capacity or sensory evaluation. Chicken meat selenium levels were clearly influenced by dietary selenium levels, but were not influenced by feed fatty acid composition. High dietary selenium level lead to marginally increased n-3 EPA and higher meat fat % in breast muscle but did not influence the other LC PUFA levels. Chicken breast meat nutritional value from the soybean oil and low selenium dietary groups may be regarded as less beneficial compared to the breast meat from the linseed oil and high selenium dietary groups. Replacing rendered animal fat with palm oil and red palm oil had no negative effects on chicken muscle nutritional value with regard to fatty acid composition. Red palm oil decreased total chicken plasma cholesterol, confirming the cholesterol reducing effect of this dietary oil.