Sustainable Intensification? Increased Production Diminishes Omega-3 Content of Sheep Milk

Nikolaos Voutzourakis,Gillian Butler,Leonidas Rempelos,Enrica Franceschin,Mick Eyre,Sokratis Stergiadis,Ioanna Atsali,Nikolaos Tzanidakis,Alexandros Stefanakis,Smaragda Sotiraki,Carlo Leifert

doi:10.3390/su12031228

Abstract

Intensifying agricultural production alters food composition, but this is often ignored when assessing system sustainability. However, this could compromise consumer health and influence the concept of “sustainable diets”. Here, we consider the milk composition of Mediterranean dairy sheep, finding inferior fatty acid (FA) profiles with respect to consumer health as a result of a more intensive system of production. Semi-intensive management produced 57% more milk per ewe, with a 20% lower fat content (but inferior fat composition). The milk had a nutritionally poorer fatty acid (FA) profile, with an 18% lower omega-3 FA concentration (n-3) (19% fewer long-chain n-3s) and a 7% lower monounsaturated FA concentration but a 3% higher saturated FA (9% higher in C14:0) concentration compared to ewes under traditional, extensive management. A redundancy analysis identified close associations between fat composition and animal diets—particularly concentrate supplementation and cultivated pasture grazing—and n-3 was associated with grazing in diverse, native mountain pastures. This paper questions if identifying such key elements in traditional systems could be deployed for “sustainable intensification” to maintain food quality while increasing output.

Highlights

Many traditional farming systems are changing, generally becoming more intensive
We identified the associations between animal nutrition and environmental drivers
While this study confirmed that Cretan Sfakiano sheep milk had fewer saturated fatty acids (SFAs) and more monounsaturated fatty acids (MUFAs), polyunsaturated fatty acids (PUFAs), and n-3s compared to published data for bovine milk [24], it highlighted the differences in milk composition brought about by flock management as well as changes within and between seasons

Summary

Introduction

Many traditional farming systems are changing, generally becoming more intensive. The rationale is increasing yields and output to increase income for farmers, and at a global level, producing sufficient food for the world’s growing population [1]. The consumption of foods from low-input production systems (such as organic food) has been linked to health benefits, including a reduced incidence of being overweight/obesity, pre-eclampsia, hypospadias, and eczema (in human cohort studies) [7], as well as type 2 diabetes [8] and metabolic syndromes [9]. It is feasible that the sustainability of our food production could be compromised if food composition is negatively affected by intensification, which possibly poses a challenge to consumer health rather than supplying vital nutrients.

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Results

Conclusion