Vitamin A stability in triple fortified extruded, artificial rice grains containing iron, zinc and vitamin A

Abstract

Multi-micronutrient-fortified rice could be an effective and sustainable approach to combat micronutrient deficiencies. We produced hot-extruded artificial rice grains fortified with 10 mg iron (as micronised ground ferric pyrophosphate), 5 mg zinc (as oxide, sulphate or carbonate) and 750 lg vitamin A ⁄ g [as retinyl palmitate (RP)] and measured RP stability. The rice was designed to be mixed 1:200 with natural rice. Mean RP losses were 5.3% during extrusion, 28.5% during storage and 9.8% during cooking. Storage losses after 18 weeks at 30°C in plastic packages exposed to light were ca 40% with iron and zinc causing no further losses. In aluminium packages (no light), mean RP losses were ca 20%. Iron, but not zinc, increased RP degradation. Zinc sulphate increased the negative effect of iron. The relatively good stability of RP during hot extrusion can be explained by the closed surface and dense nature of the artificial grain protecting RP from oxidation.

Evaluation of the effect of Ultra Rice®EDTA supplementation on the soluble iron, visual acceptance and vitamin A stability of commercial milled rice blends

“…This raises the possibility that the ‘dry RP 250 S/N’ used by Pinkaew et al . () provided better protection from the oxidants than did the RP ingredient used in the present study, and Pinkaew et al . have explicitly noted the superior performance of the ‘dry RP 250 S/N’ preparation.…”

“…The corresponding colour differences reported by Pinkaew et al . () for artificial rice fortified with a comparable level (1 g Fe/100 g) of mFePP (and with various zinc salts) were in the 9–15 range (Pinkaew et al ., ). In addition, the corresponding colour differences were calculated for iron‐fortified intact rice prepared as described by Prom‐u‐thai et al .…”

“…Although the cooking losses for batches X1–X10 (average loss = 36.4 ± 3.4%; n = 10) were generally comparable to those reported by others (Murphy et al ., ; Flores et al ., ; Lee et al ., ; Wireinga et al ., ), they were much larger (3–4×) than those reported by Pinkaew et al . (). There appeared to be at least three possible explanations for larger cooking losses in the present study: (1) a different RP ingredient, (2) a pH <5 and (3) the presence of a soluble iron ingredient (NaFeEDTA).…”

“…A rice grain sample of approximately 50 g was tested (a) after two weeks of RT storage, again (b) after twenty weeks of RT storage and once again (c) after thirty weeks of RT storage and with cooking (in the rice cooker, with 100 g of Milli‐Q Plus water) using the same parameters specified by Pinkaew et al . (): the illuminant D65 (average daylight, including UV spectra) and a 10˚ observer angle with a large reflectance spectrum. All colour determinations were performed on a single (50‐g) sample.…”

Research on Natural Resources: The Quest for Integration Revisited

“…However, other factors also need to be considered when selecting a potential zinc fortificant for extruded rice, such as potential interactions with other cofortificants other than iron, shelf-life stability, and sensory properties. For example, increased losses (30% higher) of retinyl palmitate during storage have been reported when extruded rice was fortified with ZnSO 4 rather than ZnO (38). Compared with ZnSO 4 , ZnO may be preferable due to its superior color-masking properties and attractive cost profile; the commercial price for ZnSO 4 is 3-4 times higher than for ZnO (P Moya, Dr. Paul Lohmann GmbH KG, personal communication, 2015).…”