Fatty Acid Profile, Mineral Composition, and Health Implications of Consuming Dried Sago Grubs (Rhynchophorus ferrugineus)

Abstract

A comprehensive evaluation of the fatty acid and mineral composition of Rhynchophorus ferrugineus (sago grub powder, SGP), pre-treated to meet New Zealand import biosecurity requirements, was investigated. Palmitic acid (42.5% FA), oleic acid (39.0% FA), and linoleic acid (1.02% FA) were the most abundant saturated fatty acid, monounsaturated fatty acid, and polyunsaturated fatty acid, respectively. Lipid nutritional indices of SGP fats were ω6/ω3 (2.17), hypocholesterolemic/hypercholesterolemic acid ratio (0.88), atherogenicity index (1.01), thrombogenicity index (1.65), and health-promoting index (0.99). Although there are no established recommended values for these dietary indicators, including them in a balanced diet may be advised to reduce the risk of adverse health effects. The mineral analysis profile of the SGP found 11 essential and 29 non-essential minerals, and 4 heavy metals. SGP was rich in important minerals such as potassium (1657 mg/kg DW), magnesium (805.3 mg/kg DW), iron (23 mg/kg DW), manganese (8.8 mg/kg DW), calcium (477 mg/kg DW), and phosphorus (2950 mg/kg DW). However, the Ca:P ratio (0.16:1) of SGP samples was lower than the recommended Ca:P ratio (1.3:1) needed for optimum bone health. Heavy metals such as arsenic (0.17 mg/kg DW), cadmium (0.04 mg/kg DW), lead (0.56 mg/kg DW), and vanadium (0.01 mg/kg DW) were detectable in SGP but were below acceptable toxicity limits. These findings indicate that SGP pre-treated for export is safe for consumption and contains appreciable nutrients, especially minerals. However, the nutritional and health implications of the elevated saturated fatty acid levels, low polyunsaturated fatty acid contents, and low Ca:P ratio of SGP should be considered when choosing sago grubs as a food source.