Meat processing and colon carcinogenesis: Cooked, nitrite-treated and oxidized high-heme cured meat promotes mucin depleted foci in rats

Processed meat intake is associated with colorectal cancer risk, but no experimental study supports the epidemiologic evidence. To study the effect of meat processing on carcinogenesis promotion, we first did a 14-day study with 16 models of cured meat. Studied factors, in a 2 × 2 × 2 × 2 design, were muscle color (a proxy for heme level), processing temperature, added nitrite, and packaging. Fischer 344 rats were fed these 16 diets, and we evaluated fecal and urinary fat oxidation and cytotoxicity, three biomarkers of heme-induced carcinogenesis promotion. A principal component analysis allowed for selection of four cured meats for inclusion into a promotion study. These selected diets were given for 100 days to rats pretreated with 1,2-dimethylhydrazine. Colons were scored for preneoplastic lesions: aberrant crypt foci (ACF) and mucin-depleted foci (MDF). Cured meat diets significantly increased the number of ACF/colon compared with a no-meat control diet (P = 0.002). Only the cooked nitrite-treated and oxidized high heme meat significantly increased the fecal level of apparent total N-nitroso compounds (ATNC) and the number of MDF per colon compared with the no-meat control diet (P < 0.05). This nitrite-treated and oxidized cured meat specifically increased the MDF number compared with similar non nitrite-treated meat (P = 0.03) and with similar non oxidized meat (P = 0.004). Thus, a model cured meat, similar to ham stored aerobically, increased the number of preneoplastic lesions, which suggests colon carcinogenesis promotion. Nitrite treatment and oxidation increased this promoting effect, which was linked with increased fecal ATNC level. This study could lead to process modifications to make non promoting processed meat

A randomised cross-over trial in healthy adults indicating improved absorption of omega-3 fatty acids by pre-emulsification

BACKGROUND: The health benefits of increased intakes of omega-3 fatty acids are well established but palatability often presents a problem. The process of emulsification is used in the food industry to provide a wider spectrum of use, often with the result of increased consumption. Moreover, as emulsification is an important step in the digestion and absorption of fats, the pre-emulsification process may enhance digestion and absorption. In this study the levels of plasma fatty acid and triacylglycerol (TAG) following the ingestion of either an oil mixture or an emulsified oil mixture have been compared. METHODS: In this randomised cross-over study, 13 volunteers received the oil mixture and 11 received the oil emulsion as part of an otherwise fat free meal. Blood samples were collected at 0, 1.5, 3, 4.5, 6, 7.5 and 9 hours after ingestion of oil, separated and stored at -20°C. Plasma triacylglycerols were assessed spectrophotometrically and fatty acids were determined by gas chromatography. Following a washout period of twenty days the procedure was repeated with the assignments reversed. RESULTS: The postprandial plasma TAG and the C18:3 (n-6), C18:3(n-3), C20:5(n-3) and C22:6 (n-3) polyunsaturated fatty acid (PUFA) levels for the emulsified oil group were increased significantly (P = 0.0182; P = 0.0493; P = 0.0137; P < 0.0001; P = 0.0355 respectively) compared with the non-emulsified oil group. The C16:0 and C18:0 saturated fatty acids, the C18:1 (n-9) monounsaturated fatty acid and the C18:2 PUFA were not significantly different for the oil and emulsified oil groups. CONCLUSION: Pre-emulsification of an oil mixture prior to ingestion increases the absorption of longer chain more highly unsaturated fatty acids (especially eicosapentaenoic acid and docosahexaenoic acid) but does not affect absorption of shorter chain less saturated fatty acids, suggesting that pre-emulsification of fish oils may be a useful means of boosting absorption of these beneficial fatty acids. Trial registration: Current Controlled Trials ISRCTN4320260

Contents and composition of individual phospholipid classes from biceps femoris related to the rearing system in Iberian pig

International audienceDuring dry-cured ham processing, phospholipids (PL) are the main substrates of lipolysis and oxidation. However, the published data on individual PL classes in the pig muscle are inconsistent. This study determined the PL class contents and composition in biceps femoris of Iberian pigs according to the rearing system (Montanera vs Pienso). Phosphatidylcholine (PC), phosphatidylethanolamine (PE), cardiolipin (CL) and sphingomyelin contents were higher in the Montanera pigs than in the Pienso pigs. Total PL and PC, PE, phosphatidylinositol + phosphatidylserine and CL contained higher levels of oleic acid and slightly higher levels of n-3 polyunsaturated fatty acids (PUFA) but lower levels of n-6 PUFA in the Montanera pigs than in the Pienso pigs. The rearing system had no effect on the plasmalogen content but influenced aldehyde composition, mainly in PE and in total PL. These results can partially explain the differences in sensory properties of dry-cured ham between the Montanera and Pienso systems

Emulsion encapsulation in calcium-alginate beads delays lipolysis during dynamic in vitro digestion

We assessed the behaviour of encapsulated oil-in-water emulsions in alginate beads under dynamic digestionconditions to test their suitability for ileal brake activation. A dynamic gastrointestinal digestion system (DIDGI)was used with three consecutive compartments simulating the stomach, duodenum and distal small intestine.Digestive media were collected periodically to follow lipolysis, as well as the solubilisation of absorbable lipidspecies in mixed micelles. Free emulsions (i.e., non-encapsulated) in absence or presence of empty alginate beadswere used as controls.In the free emulsions lipolysis occurred rapidly with micellar solubilisation not rate limiting, which indicatesproximal digestion and absorption. Encapsulation of emulsions in calcium-alginate beads delayed lipolysis ty-pically for 3 h by diffusion limitation, after which most probably mechanical disintegration took place. Ourfindings do not only increase the understanding of the dynamics of lipid digestion, but also directly link to thedesign of encapsulates (size and mesh size) for long-term weight management strategies

Hypervirulent Klebsiella pneumoniae infection in a woman with a CDH1 gene mutation

The CDH1 gene, which encodes E-cadherin, may be associated with cancer when mutated, but the significance of mutations in the context of infection is unknown. In this report, we describe a case of disseminated hypervirulent Klebsiella pneumoniae infection in a 49 year old Caucasian woman with a documented CDH1 mutation

n-3 fatty acid enriched eggs and production of egg yolk powders: An increased risk of lipid oxidation?

Lipid oxidation is generally favoured by thermal processing and long-term storage. Oxidised lipids can alter nutritional and sensorial properties of foods. As eggs are widely used in food industries in dried powder form, our aim was to determine whether compositional or processing parameters have an impact on lipid oxidation from the shell eggs up to the dried powders and subsequent storage. Two batches of shell eggs were processed: one issued from hens fed with a standard diet and another receiving a diet enriched in extruded linseed, rich in linolenic acid. The extent of lipid oxidation was evaluated by quantification of conjugated dienes (CD) and malondialdehyde (MDA), but also by assessment of tocopherols, lutein and zeaxanthin losses. Results highlighted the remarkable oxidative stability of control and enriched yolk powders as revealed by a moderate increase of the quantities of CD and MDA, the lack of oxidised cholesterol and small loss of a-tocopherol

Seasonal composition of lipids, fatty acids, and sterols in the edible red alga Grateloupia turuturu

International audienceComposition of lipids, sterols, fatty acids (FA), and phospholipids in the edible Rhodophyta Grateloupia turuturu from Britanny, France, was investigated over four seasons in order to identify compounds with potential benefits in health and nutrition. The lipid content was found to vary from 3.3 to 4.1 % dry weight. No marked variations were observed for glycolipids accounting for 42.3-46.8 %, whereas neutral lipids and phospholipids fluctuated from 20.1 % (summer) to 41.8 % (winter), and 11.2 % (winter) to 33.4 % (summer), respectively. Polyunsaturated FA of the total lipids were found from 20.4 % (winter) to 31.1 % (summer), including 20:5 omega 3 acid as the major one (up to 16.3 % in summer). Phosphatidylcholine (20.0-43.7 %) and phosphatidylserine (24.6-37.5 %) were the dominant phospholipids in all seasons. Compounds of interest were identified in minor amounts such as squalene, alpha-tocopherol, phytonadione (vitamin K-1), cholesteryl formate, cholest-4-en-3-one, and cholesta-4,6-dien-3-one. Cholesterol was the major sterol with a lower content in spring and summer

Lipid and amino acid profiles support the potential of Rhynchophorus phoenicis larvae for human nutrition

This work was supported in part by the SCAC (Service de Coopération et d’Action Culturelle) of the French Ambassy of Yaoundé – Cameroon [Code projet Prisme/Numéro Prisme: 0185 CMR B16 0011]The authors wish to thank Lucie Ribourg, Marion De Carvalho and Mathieu Fanuel for helping us in tocopherol analysis, DSC analysis of lipid extracts and MALDI TOF analysis of TAGs structures. We also thank John Fogoh Muafor from Living Forest Trust (LIFT) and Ministry of Forestry and Wildlife (Cameroon) for providing the larvae from the wildIn view of future use of insects in the diet, Rhynchophorus phoenicis larvae were evaluated for their potential as protein and lipid sources. Their lipid and protein contents represented 21.35 +/- 2.01 g/100 g and 8.18 +/- 0.44 g/100 g fresh weight (FW), respectively, with energy content of 940.0 kJ (224.9 kcal)/100 g FW. Indispensable amino acids were in higher amounts than in Food and Agriculture Organization (FAO) reference protein, with remarkably high scores for tryptophan and sulfur amino acids. Total lipids comprised neutral lipids (97.53 +/- 0.05 g/100 g lipid), glycolipids (0.59 +/- 0.04 g/100 g), phospholipids (1.88 +/- 0.06 g/100 g) and tocopherols (146 +/- 13 mu g/g). Total and neutral lipids had palmitic and oleic acids (38 and 46 g/100 g total fatty acids, respectively) as main fatty acids, and palmitoyl, dioleylglycerol (POO) (36.4 +/- 0.3%) and dipalmitoyl, oleylglycerol (PPO) (30.3 +/- 0.3%) as main triacylglycerol molecular species. This composition explains the lipid melting/crystallization profile. Polyunsaturated fatty acids represented 0.76 +/- 0.17 g/100 g fresh larvae (linoleic acid: 0.58 +/- 0.11 g/100 g; alpha-linolenic acid: 0.17 +/- 0.06 g/100 g). They concentrated in the phospholipids, characterised by a majority of choline-carrying species and high levels of lyso-phospholipids. These results confirm that Rhynchophorus phoenicis larvae are a potential alternative source of dietary fat and proteins that can be used to address under-nutrition and malnutritio