Total Carotenoid Retention Research Articles

Characterization and Optimization of Extrusion Cooking for the Manufacture of Third‐Generation Snacks with Winter Squash (Cucurbita moschata D.) Flour

ABSTRACTThe aim of this work was to study the effects of barrel temperature (BT, 93.5–140.5°C), feed moisture (FM, 21.3–34.7%), and winter squash flour content (SFC, 0.43–15.6%) on physicochemical properties of microwave‐expanded third‐generation snack foods obtained by extrusion. Physicochemical properties used for optimization were expansion index (EI), penetration force (PF), specific mechanical energy (SME), and total color difference (ΔE). Response surface methodology was used for the analysis of data. The highest values of EI and lowest values of PF were found at high BT and low FM. The lowest values of SME were obtained at high levels of FM throughout the range of BT and SFC, whereas the highest values of ΔE were obtained at high SFC and low FM. Increasing levels of SFC increased ΔE values, whereas EI and SME values decreased. The best processing conditions (EI > 6.0, PF < 9.5 N, SME < 172 kJ/kg, and ΔE < 18) were found in the range of BT, 122–141°C; FM, 24.7–29.5%; and SFC, 0–10.9%. Under optimal process conditions, the retention of total carotenoids was higher than 60%. It is possible to manufacture third‐generation snack foods with good physicochemical properties, which could bring a health benefit because of the presence of carotenoids and dietary fiber in winter squash flour.

Impact of cooking and drying on the phenolic, carotenoid contents and in vitro antioxidant capacity of Andean Arracacha (Arracacia xanthorrhiza Bancr.) root

The influence of different cooking regimes such as boiling, oven, microwave and hot-air drying on the retention of total phenolics (TP), total carotenoids (TC) and in vitro antioxidant capacity (AC) for three colored arracacha roots was studied. Continuous losses of TP, TC and AC during the course of the different cooking processes were observed. Boiling at 99.5° C for 20 min turned to be the best method to cook this root due to a high retention of TP, TC and AC in comparison to oven cooking at 200° C for 45 min and microwave cooking at 800 W for 5 min. During boiling, chlorogenic and caffeic acids and derivatives remained relatively stable. The drying temperature was negatively correlated to the residual content of TP and AC for the yellow and cream arracacha roots, but for the cream/purple arracacha variety, blanching preserved the TP and AC. Significant losses in chlorogenic and caffeic acids and derivatives were mainly observed during hot-air drying. These results suggested that TP are responsible to a large extent of the AC displayed by arracacha root during the different evaluated cooking regimes.

Retention of carotenoids in orange-fleshed sweet potato during processing

The retention of carotenoids was studied in the storage roots of ten sweet potato clones possessing different intensities of dark orange-flesh colour in four different processing methods-oven drying, boiling, sun drying and frying. The results indicated that the extent of retention varied with the method of processing. The highest retention was observed in oven drying (total carotenoids 90%-91% and β-carotene 89%-96%) followed by boiling (total carotenoids 85%-90% and β-carotene 84%-90%) and frying (total carotenoids 77%-85% and β-carotene 72%-86%). The lowest retention of total carotenoids (63%-73%) and β-carotene (63%-73%) was recorded in the sun drying method.

Effect of processing on the retention of carotenoids in yellow-fleshed cassava (Manihot esculenta Crantz) roots

Summary The retention of carotenoids was studied in roots from yellow-fleshed, high carotene cassava clones in four different processing methods. The results indicated that the extent of retention varied with the method of processing. The highest retention was observed in oven drying (total carotenoids 54.70–84.01% and β-carotene 63.90–94.53%) followed by boiling (total carotenoids 47.87–83.79% and β-carotene 51.31–81.04%) and frying (total carotenoids 48.76–79.77% and β-carotene 44.11–83.87%). The lowest retention of total carotenoids (32.86–56.40%) and β-carotene (21.47–56.68%) was recorded in the sun drying method. The variation in the total carotenoids and β-carotene content depends on variety, processing method and initial carotene content of the fresh root.

Response of rainbow trout (Oncorhynchus mykiss) to varying dietary astaxanthin/canthaxanthin ratio: colour and carotenoid retention of the muscle

Rainbow trout with an average initial weight of 160 g were fed during 42 days diets containing varied keto-carotenoids astaxanthin (Ax)/canthaxanthin (Cx) ratio, as follows: Ax 100% : Cx 0%; Ax 75% : Cx 25%; Ax 50% : Cx 50%; Ax 25% : Cx 75% and Ax 0% : Cx 100%. Muscle colour and carotenoid muscle retention were studied. Colour parameter values for mixed astaxanthin-canthaxanthin-fed fish were intermediate between those obtained for Ax 0% : Cx 100% fed fish group and for Ax 100% : Cx 0% fed fish group. Concerning muscle carotenoid retention, it has been observed that as the level of canthaxanthin in diet increased, the muscle total carotenoid retention decreased. In the mean time, as the level of canthaxanthin in diet increased, the muscle astaxanthin retention decreased while that of canthaxanthin increased. The results reported here provide further evidence of non-beneficial effects in terms of muscle colour and muscle carotenoid retention of the use of varying dietary astaxanthin/canthaxanthin ratio for feeding rainbow trout compared to values obtained for astaxanthin-only feed.

Effect of drying and storage on the degradation of total carotenoids in orange‐fleshed sweetpotato cultivars

Orange-fleshed sweetpotato (OFSP) can be used to tackle vitamin A deficiency, a major public health problem in most developing countries. In East Africa, common ways of using sweetpotato include drying and subsequent storage. The aim of the study was to investigate the impact of drying and storage on the total carotenoid retention (as an estimate of provitamin A retention) from OFSP. Losses of total carotenoid during drying were generally low (15% or less). Total carotenoid retention in OFSP was not dependent on the type of dryer (solar or sun). Sweetpotato cultivar (Ejumula, Kakamega, SPK004/1, SPK004/1/1, SPK004/6 or SPK004/6/6) had a significant effect on retention in drying (P < 0.05). High percentage losses of total carotenoids were, however, correlated with high moisture content and high carotenoid content in fresh sweetpotato roots. After 4 months' storage at room temperature in Uganda, losses of total carotenoid in dried sweetpotato chips were high (about 70%) and this was not dependent on the use of opaque or transparent packaging. Losses of carotenoids during storage were considered to be more of a nutritional constraint to the utilisation of dried sweetpotato than losses occurring during drying. The relationship between characteristics of the cultivars and losses of carotenoids during drying should be taken into account in selection of cultivars for processing.

RELATIVE SUITABILITY OF PLASTIC FILMS FOR THE FROZEN STORAGE OF MANGO PULP

Thermally blanched and unblanched mango pulp of three commercial varieties were packed in polyetlrylene, polypropylene and paper-Al foil-polyetltylene laminate pouches, frozen and stored at –12°C for 12 months. Blanched samples were found to be more stable than he corresponding unblanched samples and samples stored in foil laminate pouches were rated superior to all other samples. Retention of total carotenoids in blanched samples ranged between 79.7–95.1% in foil laminate, 56.7–82.5 % in polypropylene and 50.9–71.9 % in polyethylene pouches while ascorbic acid retention was 56.8–88.4%, 13.4–36.0% and 11.0–19.7%, respectively, in laminate, polypropylene and polyethylene pouches after 12 months storage. Total sugar and acidity did not change appreciably during frozen storage of mango pulp.

Leaf senescence in a non‐yellowing mutant of Festuca pratensis: Degradation of carotenoids

The loss of pigments was assessed in detached leaves of Festuca pratensis Huds. kept in permanent darkness. Two genotypes, a normal yellowing cultivar Rossa and a non‐yellowing mutant Bf 993 were compared with each other. Analysis of individual pigments, chlorophylls. β‐carotene, lutein, violaxanthin and neoxanthin was performed using HPLC. In the non‐yellowing genotype the high retention of chlorophylls was associated with an equally high retention of total carotenoids. Although the two genotypes differ markedly with regard to the rate of pigment loss, the ratios of yellow to green pigments did not change significantly during dark‐induced senescence. At the end of the senescence period β‐carotene was retained to a higher degree than the xanthophylls, particularly in the yellowing genotype. In the mutant leaves the ratio of chlorophyll a to b remained nearly constant, whereas in leaves of the normal genotype a preferential retention of chlorophyll b was observed towards the end of the senescence period. It is concluded that the thylakoids of the non‐yellowing genotype retain all the principal components of protein‐pigment complexes, i.e. chlorophylls, carotenoids and apoproteins. Possible explanations for the stability of these complexes in the mutant are discussed.

Effect of dehydration, processing and storage on biological availability of carotenoids in alfalfa

1. There were no differences in the total carotenoid retention between groups fed on diets containing fresh (as freeze‐dried) or dehydrated alfalfa meal but in the former group there were significant increases in the serum, liver and skin carotenoids. 2. It is suggested that the isomers formed during dehydration processing and storage are not completely available for skin pigmentation.