Acute Evidence of Digestive, Metabolic and Nutritional Differences in Beef and Meat- Analogue Meals

Red meat consumption contributes important nutrients to the diet, including essential amino acids, long chain and complex lipids, vitamins (including B12) and minerals (including iron and zinc) [5]. While supplying these important nutrients, red meat may contain components which may negate optimal health such as the saturated fat content and nitrates, that are added during processing [5]. The degree to which red meat affects health is likely related to its inherent nutritional profile, the quantity consumed and any processing (e.g. nitrates or cooking techniques). Regardless, the simple notion of a complex whole-food containing single nutrients which are 'good' or 'bad' for health is now considered overly simplistic [6]. For example, to reduce heart disease, nutritional guidelines now suggest an increase in polyunsaturated fats at the expense of saturated fat, rather than a complete reduction of all fats [6].

Alongside the controversy over the health consequences of red meat, recent attention has focused on the possibility of using "plant-based" proteins as an alternative to red meat consumption. The search for meat alternatives has resulted in a sharp increase in the production of novel "plant-based" meat analogues that have been designed to replicate the taste and eating experience of red-meat. To date there are very few studies addressing the nutritional differences between traditional red meat and plant-based meat analogues, and the nutritional differences that arise due to different production systems. Given the nutritional composition of red meat is likely to be influenced by the farming and feeding practices of the animals, production procedures and end-user cooking techniques [7], these differences need to be accounted for in the research design and application.

Aims: To investigate the digestive responses to an acute intake of pasture-fed beef, grain-finished beef, lamb and a plant based meat-analogue consumed as a component of a mixed meal. This study is part of a larger programme to understand the nutritional implications of consuming New Zealand, pasture-fed red meat as part of a balanced diet.

Study Design and Setting: The study is designed as randomised cross-over trial to capture biological difference in postprandial nutrient dynamics. Research subjects will act as their own controls and will consume each meal (pasture raised, grain-fed beef, lamb and a meat alternative meal) on a separate occasion in random order. The study compares exemplars of pasture-fed New Zealand beef, grain-finished New Zealand beef, lamb and a meat analogue. The plant-based meat analogue has been selected on the basis of its macronutrient profile (protein and fat) and appearance in order to that best matches that of meat.

The digestion and metabolism of key nutrients in beef will be measured immediately after the ingestion of a single meal. This experimental setting will also be used to examine some subjective qualities of the meal experience, such as satisfaction score (i.e., liking, satisfaction, enjoyment, satiety, appetite) and gastrointestinal score (i.e., comfort, fullness, bloating, rumbling, flatulence, faecal urgency, diarrhoea).