Carotenoid transfer to oil during thermal processing of low fat carrot and tomato particle based suspensions

Impact of Cultivar Selection and Thermal Processing by Air Drying, Air Frying, and Deep Frying on the Carotenoid Content and Stability and Antioxidant Capacity in Carrots (Daucus carota L.)

Epidemiological data suggest that consuming diets rich in carotenoids can reduce the risk of developing several non-communicable diseases. Thus, we investigated the extent to which carotenoid contents of foods can be increased by the choice of food matrices with naturally high carotenoid contents and thermal processing methods that maintain their stability. For this purpose, carotenoids of 15 carrot (Daucus carota L.) cultivars of different colors were assessed with UHPLC-DAD-ToF-MS. Additionally, the processing effects of air drying, air frying, and deep frying on carotenoid stability were applied. Cultivar selection accounted for up to 12.9-fold differences in total carotenoid content in differently colored carrots and a 2.2-fold difference between orange carrot cultivars. Air frying for 18 and 25 min and deep frying for 10 min led to a significant decrease in total carotenoid contents. TEAC assay of lipophilic extracts showed a correlation between carotenoid content and antioxidant capacity in untreated carrots.

Applying Pulsed Electric Fields to Whole Carrots Enhances the Bioaccessibility of Carotenoid and Phenolic Compounds in Derived Products

We propose the application of pulsed electric fields (PEF) to carrots to obtain derived products with increased phenolic and carotenoid bioaccessibility. For this purpose, juices, purees, and oil-added purees were obtained from whole PEF-treated carrots (five pulses of 3.5 kV cm-1; 0.61 kJ kg-1). In order to obtain shelf-stable products, the effect of a thermal treatment (70 °C for 10 min) was also studied. Carrot juices exhibited the highest carotenoid (43.4 mg/100 g fresh weight) and phenolic (322 mg kg-1 dry weight) contents. However, caffeic and coumaric acid derivatives were highly sensitive to PEF. The phenolic bioaccessibility reached 100% in purees obtained from the PEF-treated carrots, whereas the further thermally treated oil-added purees exhibited the greatest carotenoid bioaccessibility (7.8%). The increase in carotenoid bioaccessibility could be related to their better release and solubilization into micelles. The results suggest that food matrix aspects apart from particle size (e.g., pectin characteristics) are involved in phenolic bioaccessibility.

Carotenoid absorption in rats fed with vacuum-fried papaya chips depends on processed food microstructure associated with saturated and unsaturated oils

Many studies indicate that food matrix microstructure and type of dietary oil or fat play a key role in carotenoid absorption. Therefore, this work was designed to highlight the relationship between processed food microstructure and carotenoid absorption. This study aimed to evaluate the consumption of a carotenoid-rich fruit snack on lipid profile, glycemia and especially on carotenoid absorption/bioconversion in Wistar rats. Animals were fed with mixtures based on vacuum-fried papaya chips with either soy oil (PC-S) or palm oil (PC-P) during 7 days, receiving 0.29 mg lycopene/kg/day and 0.35 mg total carotenoids/kg/day. Lycopene and retinoids were analyzed in plasma and liver of rats by HPLC-DAD. Results showed that the consumption of mixtures based on papaya chips did not affect the lipid profile or glycemia in rat plasma, regardless the type of oil. Wide-field and confocal microscopy analyses of food matrix helped to understand why lycopene accumulation in the liver was higher (p < 0.05) in rats fed with PC-P (0.442 µg/g liver) than in those fed with PC-S (0.291 µg/g liver). A better dissolution of crystalloid lycopene was found in PC-P. Conversely, a higher bioconversion of provitamin A carotenoids was observed for soy products. The effect of type of oil was underlined by epifluorescence microscopy of papaya mixtures showing homogeneous and small lipid droplets for soy products. These results showed that PC-S could be recommanded as a healthy snack, being a source of provitamin A carotenoids and bioavailable lycopene in a diversified diet.

Using Extra Virgin Olive Oil to Cook Vegetables Enhances Polyphenol and Carotenoid Extractability: A Study Applying the sofrito Technique

Olive oil is the main source of fat in the Mediterranean diet and the most frequently used ingredient in Mediterranean cuisine. Cooking with olive oil has been attracting attention because it can act as a food excipient, thereby increasing the bioaccessibility and bioavailability of ingested bioactive compounds. The aim of this study was to understand the effect of cooking with olive oil on the bioactive components in other ingredients (tomato, onion, and garlic) of sofrito sauce, a representative model of Mediterranean cuisine. After the cooking process, polyphenols from tomato, onion, and garlic were detected in the olive oil, especially naringenin, ferulic acid, and quercetin, as well as a high content of carotenoid Z-isomers, which are more bioavailable than the E-isomers. Therefore, traditional Mediterranean cuisine could play an important role in the health-improving effects of the Mediterranean diet.