Characterization of the behavior of carotenoids from pitanga (Eugenia uniflora) and buriti (Mauritia flexuosa) during microemulsion production and in a dynamic gastrointestinal system

Uncommon tropical fruits are emerging as raw-material for new food products with health benefits. This work aimed at formulating and processing microemulsions from pitanga (Eugenia uniflora) and buriti (Mauritia flexuosa) fruits, since they are very rich in carotenoids (particularly lycopene and β-carotene), in order to encapsulate and increase carotenoids' bioaccessibility. Pitanga and buriti microemulsions were produced by applying a direct processing (high-speed homogenization at 15,000 rpm and ultrasound with 20 kHz probe at 40% amplitude) of the whole pulp together with surfactant (Tween 80 or Whey Protein Isolate at 2%) and corn oil (5%). All treatments (HSH-US for 0-4, 4-0, 4-4, 4-8 min-min) applied were able to increase the amount of carotenoid released. However, the processing also decreased the total amount of carotenoids in the whole pulp of studied fruits. The impact of processing during microemulsion production was not severe. The overall data suggest that the presence of surfactant and oil during processing may protect the carotenoids in fruits and microemulsions. Final recovery of total carotenoids, after passing the samples through a dynamic gastrointestinal system that simulates the human digestion, was higher for microemulsions than for whole pulps. High losses of total carotenoids in buriti and β-carotene and lycopene in pitanga occurred during jejunum and ileum phases. The present work confirms that it is possible to increase β-carotene and lycopene bioaccessibility from fruits by directly processing microemulsions (p < 0.01).

Non-conventional Tropical Fruits: Characterization, Antioxidant Potential and Carotenoid Bioaccessibility

Eleven non-conventional tropical fruits were evaluated regarding their nutritional value, antioxidant potential, carotenoid contents and bioaccessibility. The fruits were chosen due to their spread through the Brazilian territory: araçá-boi, jaracatiá, cambuití, seriguela, capeba, pitangatuba, pitanga, buriti, acerola, dovialis and abricó-da-praia. Results have shown that these fruits are in general, i.e. depending on the fruit, rich sources of dietary fibers and minerals, high in moisture, and low in proteins. Twelve carotenoids were analyzed by HPLC-DAD and results ranged from 0.04 to 104 μg/g wet weight. Xanthophylls stood out, being higher than carotenes for araçá-boi, seriguela, pitangatuba and dovialis. Bioaccessibility varied both between fruits and carotenoids ranging from 2 to 75%. Although the fruit matrix effect, xanthophylls were more bioaccessible than carotenes, while lycopene and γ-carotene presented the poorest bioaccessibility. The present study is fundamental to expand the knowledge about the fruit properties, carotenoids bioaccessibility and potential benefits for health, as well to preserve natural resources and encourage the intake of new fruits for human nutrition.

Influence of gamma radiation on the physical and sensory properties of two Brazilian rice cultivars

BACKGROUND

Little has been reported about the effects of gamma radiation on the physical and sensory characteristics of rice. Samples were irradiated with ⁶⁰ Co in doses 0, 1, 2 and 5 kGy, on a rate of 0.4 kGy h^-1 .

RESULTS

The evaluation of instrumental color showed that increasing doses promoted the yellowing (higher b* value) of the rice grains. Hardness was decreased and stickiness was increased in cooked rice with increasing doses. Sensory evaluation using quantitative descriptive analysis showed that increasing doses promoted higher occurrence of yellowish appearance, emergence of burnt aroma, and an increase of bitter and burnt taste. The sensory acceptance test by 9-point hedonic scale showed alteration of the samples irradiated with 5 kGy in all evaluated attributes (appearance, color, aroma, taste and texture). The lowest dose (1 kGy), however, had good acceptability by the panelists.

CONCLUSION

Rice may be subjected to 1 kGy dose of gamma radiation without changes or with small changes in physical properties and with good overall acceptability. © 2016 Society of Chemical Industry.

The Lactococcus genus as a potential emerging mastitis pathogen group: A report on an outbreak investigation

The bacterium Lactococcus lactis is widely used in food production and in medical applications, and is considered safe for human and animal use. However, studies have also linked Lactococcus bacteria to infection. For example, certain variants of Lactococcus species have been associated with bovine mastitis (e.g., Lactococcus lactis and Lactococcus garvieae). In this study, we investigated an outbreak of bovine mastitis thought to be associated with Lactococcus bacteria by using microbiological and molecular techniques. We used bacterial isolation, next-generation sequencing, DNA fingerprinting, and other methods to test our hypothesis that Lactococcus microbes were the primary pathogen causing the mastitis outbreak. Twenty-eight Lactococcus isolates were obtained from mastitic milk of 28 dairy cows. The isolates were identified as L. lactis (27 isolates) and L. garvieae (1 isolate). Phylogenetic analysis based on 16S rDNA gene sequence comparison indicated similarity among the L. lactis isolates as well as between the isolates and reference sequences. The DNA fingerprinting analysis based on random amplified polymorphic DNA results of the 27 L. lactis isolates identified different random amplified polymorphic DNA profiles, which suggests they originated from multiple sources. Microbiome analysis determined Lactococcus to be the dominant genus in the majority of the mastitic milk samples, whereas it was found in low relative abundance in healthy milk samples. The Lactococcus genus was detected in all environmental samples tested, and sampling of bulk tank milk corroborated that Lactococcus was not abundant in healthy milk from the same dairy herd. In summary, our findings suggest that Lactococcus bacteria are a potential etiological agent in the mastitis outbreak studied. Further studies should be conducted to understand the importance of Lactococcus, especially L. lactis, as pathogenic microbes in veterinary medicine and food safety.

Pineapple by-product and canola oil as partial fat replacers in low-fat beef burger: Effects on oxidative stability, cholesterol content and fatty acid profile

The effect of freeze-dried pineapple by-product and canola oil as fat replacers on the oxidative stability, cholesterol content and fatty acid profile of low-fat beef burgers was evaluated. Five treatments were performed: conventional (CN, 20% fat) and four low-fat formulations (10% fat): control (CT), pineapple by-product (PA), canola oil (CO), and pineapple by-product and canola oil (PC). Low-fat cooked burgers showed a mean cholesterol content reduction of 9.15% compared to the CN. Canola oil addition improved the fatty acid profile of the burgers, with increase in the polyunsaturated/saturated fatty acids ratio and decrease in the n-6/n-3 ratio, in the atherogenic and thrombogenic indexes. The oxidative stability of the burgers was affected by the vegetable oil addition. However, at the end of the storage time (120 days), malonaldehyde values of CO and PC were lower than the threshold for the consumer's acceptance. Canola oil, in combination with pineapple by-product, can be considered promising fat replacers in the development of healthier burgers.

Comparison of content and in vitro bioaccessibility of provitamin A carotenoids in home cooked and commercially processed orange fleshed sweet potato (Ipomea batatas Lam)

Vitamin A deficiency (VAD) remains a public health problem in some regions of Brazil. Increased use of orange-fleshed sweet potato (OFSP) as a source of pro-vitamin A represents a potential strategy for prevention of VAD. We compared the pro-vitamin A content, vitamin A equivalency and bioaccessibility of β-carotene (βC) of two varieties of home cooked OFSP and two commercial sources of processed OFSP. Pro-vitamin A carotenoid content in home cooked, Beauregard variety of OFSP exceeded that in Amelia variety and commercial products for babies. All-trans-βC was the most abundant carotenoid in raw, cooked and commercial OFSP. Boiling and frying OFSP generally decreased total βC. A serving of 100 g FW Beauregard variety of cooked OFSP contained greater than 100% of the estimated average requirement (EAR) for children and women, and up to 92% EAR for lactating women. Although the efficiency of micellarization of all-trans-βC during simulated digestion of OFSP was relatively low (4-8%) and significantly less than for cis-isomers, the quantities of trans-βC incorporated into micelles from boiled Beauregard and fried Amelia varieties exceeded that in micelles generated by digesting commercial OFSP. The bioaccessibility of pro-vitamin A carotenoids in the micelle fraction of digested OFSP was confirmed with differentiated cultures of Caco-2 human intestinal cells. Continued development of OFSP such as the Amelia and Beauregard varieties that are rich in trans-βC and dissemination of best practices for home cooking are encouraged to increase consumption of this food to decrease the risk of vitamin A deficiency in Brazil.

Impact of genotype and cooking style on the content, retention, and bioacessibility of β-carotene in biofortified cassava (Manihot esculenta Crantz) conventionally bred in Brazil

Biofortification is a strategy for decreasing micronutrient deficiencies in vulnerable populations by increasing nutrient density in staple food crops. Roots from five varieties of cassava biofortified with β-carotene (βC), three parental accessions, and one variety of commonly consumed white cassava from Brazil were investigated. Roots from biofortified varieties contained up to 23-fold higher βC than white cassava, and the additional complement of βC was primarily the all-trans isomer. At least 68% of βC per gram fresh weight was retained after boiling or boiling and briefly frying. Micellarization of βC during simulated digestion of fried root exceeded that of boiled root. Apical uptake of all-trans-βC from mixed micelles by Caco-2 cells was affected by an interaction between variety and cooking style. These results suggest that Brazilian cassava biofortified with βC has the potential to reduce vitamin A deficiency without requiring major changes in local and ethnic styles of home cooking.

Iron bioavailability of common beans (Phaseolus vulgaris L.) intrinsically labeled with (59)Fe

A radiobioassay was performed in rats with or without iron depletion to evaluate the iron bioavailability of diets enriched with common beans and with "multimixture", a nutritional supplement based on parts of foods that are not usually eaten. The full-body (59)Fe level was determined after 5h, the absorbed (59)Fe level was determined after 48 h, and the amount of (59)Fe retained was determined after 7 days. Iron bioavailability was assessed by the full-body radioactivity of the animals, determined using a solid scintillation detector. The iron bioavailability of common beans was higher in the iron-depleted animals (55.7%) than in the non-depleted animals (25.12%) because of the higher absorption rate in the iron-depleted animals. The multimixture did not influence dietary iron bioavailability. In addition, the iron bioavailability of common beans was similar to that observed in the standard source of iron for Wistar rats. Hence, common beans may be considered an adequate dietary iron source because of its high bioavailability.

Bioavailability of iron in the regional basic diet (RBD) with dietary supplement in Brazil

The consumption of the regional basic diet (RBD) determines a state of malnutrition found in the low-income population of Northeastern Brazil. A dietary supplement known as multimixture has been used as an alternative source of iron in food for the prevention and/or treatment of anemia and for the recovery from malnutrition. The purpose of the present work was to evaluate the bioavailability of iron in the RBD supplemented with multimixture in iron-depleted and non-depleted Wistar rats. To produce iron depletion in the animals, pretest depletion diets without iron and the pretest control diet based on the AIN-93 diet were used for 8 weeks. This phase was followed by the test diets: control, AIN-93 extrinsically labeled with (59)FeCl(3); RBD, containing carioca beans intrinsically labeled with (59)Fe; and RBDMM, RBD plus multimixture, supplied in a single meal. Hemoglobin concentration, weight gain, and dietary intake were determined in the pretest phase. Iron bioavailability was determined by the determination of total-body radiation in the animals for 7 days, using a solid scintillation detector. The hemoglobin concentration, weight gain, and dietary intake were greater in the non-depleted animals than in the iron-depleted ones. The iron bioavailability of the diets did not differ significantly. It was concluded that the multimixture did not affect the bioavailability of Fe contained in the beans of the RBD.

[Nutritional evaluation of rice flour fermented with Rhizopus oligosporus]

In order to increase the proteic content of rice meal, fermentation with Rhizopus oligosporus was performed. During fermentation, samples were taken at the times of 0,20,30,40,50,60,70 and 80 hours. These samples were oven dried and further analysed. The amino acid composition of rice meal had lysine and threonine the most limiting ones. After fermentation the lysine content increase and the more limiting were the sulfur amino acids methionine and cystine (76.04%), threonine (91.03%) and lysine (97,04%. With the aim of verifying the biological value of the protein a bioassay was carried out. The fermented rice meal presented a higher digestibility value and the net protein utilization for the fermented rice meal lower than for the non fermented one.