Comparative study of salt, total fat and sugar contents of mayonnaise and salad dressings from the Iranian market.

BACKGROUND: Dietary intake of fat, salt and sugar is important for prevention of noncommunicable diseases; therefore, evaluation of these constituents in industrial packaged foods is necessary. AIMS: To compare the levels of fat, salt and sugar in mayonnaise and salad dressings commercialized in the Islamic Republic of Iran in 2017 and 2019, and to monitor compliance with standard limits. METHODS: The levels of fat, salt and sugar in 12 mayonnaise and 47 salad dressing samples collected from an Iranian market were evaluated according to the Iranian Institute of Standards and Industrial Research of Iran (ISIRI) and compared between 2017 and 2019. RESULTS: We determined compliance with ISIRI limits and other standard targets. The salt content of mayonnaise samples significantly decreased from 2.03 (standard deviation; 0.3) g/100 g in 2017 to 1.61 (0.12) g/100 g in 2019 (P = 0.031). Total sugar level of mayonnaise samples significantly decreased from 5.97 (1.14) g/100 g in 2017 to 3.63 (0.53) g/100 g in 2019 (P = 0.005). The total sugar level of salad dressings significantly decreased from 8.97 (2.34) g/100 g in 2017 to 1.58 (2.65) g/100 g in 2019 (P = 0.039). Compliance of mayonnaise and salad dressing fat contents with ISIRI limits increased from 42.9% and 84.6% in 2017 to 100% and 90.5% in 2019, respectively. None of the mayonnaise samples met the British Food Standards Agency salt target (maximum 1.25 g/100 g) in 2017 and 2019. CONCLUSIONS: Reformulation of these products for reduction of salt and sugar content is necessary.

Evaluating the rancidity and quality of discarded oils in fast food restaurants.

This cross-sectional study attempts to determine the rancidity and quality of discarded oils in fast food restaurants. Samples of the discarded frying oils were collected randomly from 50 fast food restaurants in Tehran, Iran. Their physicochemical properties were assessed and compared to the standard values. The means (±SD) of the physicochemical indicators of the rancidity in the discarded oils were as follows: peroxide value, 3.06 (0.51) (mEq/kg); free fatty acids content, 1.52 (2.26) (%); p-anisidine value, 57.63 (4.02) (mEq/kg); total oxidation value, 64.53 (4.15); total polar compounds (TPC), 20.19 (1.02) (%); viscosity, 107.87 (2.35) (cp); and red color, 9.64 (0.84). Positive correlations were found between the TPC, viscosity, and red color (p ≤ 0.01) of the oil samples. The majority of discarded oil from fast food restaurants were overdegraded containing hazardous secondary oxidative products, and also, the consumption of nonstandard frying oil has increased in fast food restaurants. Policymakers should develop guidelines to determine whether and when frying oils should be discarded and consider the consumption of overdegraded oils as a public health hazard.