Bioaccessibility of Antioxidants in Blackcurrant Juice after Treatment Using Supercritical Carbon Dioxide.

Blackcurrant juice (Ribes nigrum L.) was subjected to supercritical carbon dioxide (SCCD) at 10, 30, and 60 MPa for 10 min at 45 °C, as well as thermally treated at 45 and 85 °C for 10 min to determine the stability, antioxidant capacity (AC), and bioaccessibility (BAc) of vitamin C, total anthocyanins, and their individual monomers. An in vitro gastrointestinal digestion model completed with dialysis was used to assess BAc. The use of SCCD at each of the pressures applied improved the stability of vitamin C, total anthocyanins, and AC before in vitro digestion. As a result of digestion, the total content of vitamin C, anthocyanins, and AC decreased. The highest BAc of vitamin C was noted in fresh juice (FJ) (40%) and after mild heat treatment at 45 °C (T45) (46%). The highest BAc of total anthocyanins was also noted in the FJ (4.4%). The positive effect of the application of SCCD on the BAc of the delphinidin-3-O-glycosides was observed compared to T45 and thermal pasteurization at 85 °C (T85). Although SCCD did not significantly improve the BAc of vitamin C and total anthocyanins, the higher AC of SCCD samples after intestinal digestion (ABTS+• and DPPH•) and in dialysate (ABTS+•) compared to thermally treated was observed. The protocatechuic acid was detected by UPLC-PDA-MS/MS as the major metabolite formed during the digestion of delphinidin-3-O-rutinoside. This may indicate the influence of SCCD on improvement of the accessibility of antioxidants for digestion, thanks to which more metabolites with high antioxidant activity were released.

Probiotic Sheep Milk Ice Cream with Inulin and Apple Fiber.

The aim of the study was to assess the effect of the addition of inulin and the replacement of part of the inulin with apple fiber on the physicochemical and organoleptic properties of ice cream. Moreover, the survival of Bifidobacterium animalis ssp. Lactis Bb-12 and Lactobacillus rhamnosus was studied in sheep milk ice cream. There was no effect of the apple fiber and the type of bacteria on the number of bacteria in the probiotics after fermentation. As a result of freezing, in the mixture containing Bifidobacterium animalis ssp. Lactis Bb-12, there was a significant reduction in the bacteria from 0.39 log cfu g-1 to 0.46 log cfu g-1. In all of the ice cream on the 21st day of storage, it exceeded 10 log cfu g-1, which means that the ice cream retained the status of a probiotic product. The Lactobacillus rhamnosus ice cream showed a lower yellow color compared to the Bifidobacterium Bb-12 ice cream. The overrun of the sheep's milk ice cream was within the range of 78.50% to 80.41%. The appearance of the sheep's milk ice cream is influenced significantly by the addition of fiber and the type of bacteria and the interaction between the type of bacteria and the addition of fiber, and storage time and fiber.

The Use of Olkuska Sheep Milk for the Production of Symbiotic Dairy Ice Cream.

The aim of this study was to determine the possibility of using Olkuska sheep milk for the production of ice cream with probiotics and prebiotics. The study examined the effect of the storage and type of bacteria used for the fermentation of ice cream mixes and partial replacement of inulin with apple fiber on the physicochemical properties, viability of probiotic cultures and organoleptic properties of sheep's milk ice cream stored at -22 °C for 21 days. The addition of apple fiber reduced the pH value of ice cream mixes before fermentation. In ice cream mixes and ice cream with apple fiber, the lactic acid content was higher by 0.1-0.2 g L-1 than in their equivalents with inulin only. These differences persisted during the storage of the ice cream. After fermentation of the ice mixes, the bacterial cell count ranged from 10.62 log cfu g-1 to 12.25 log cfu g-1. The freezing process reduced the population of probiotic bacteria cells in ice cream with inulin from 0.8 log cfu g-1 in ice cream with Lactobacillus acidophilus, 1.0 log cfu g-1 in ice cream with Lacticaseibacillus paracasei and 1.1 log cfu g-1 in ice cream with Lacticaseibacilluscasei. Freezing the varieties with apple fiber also resulted in a reduction of viable bacterial cells from 0.8 log cfu g-1 in ice cream with L. paracasei and Lb. acidophilus to 1 log cfu g-1 in ice cream with L. casei, compared to the results after fermentation. The highest percentage overrun was determined in ice cream with L. paracasei and Lb. acidophilus. Ice cream with L. casei was characterized by significantly lower overrun on the 7th and 21st days of storage. Although L. paracasei ice cream had the highest overrun, it did not cause a significant reduction in the probiotic population during storage. After seven days of storage, the first drop differed significantly depending on the type of bacteria used for fermentation of the mixture and the addition of apple fiber. L. casei ice cream had a longer first drop time than L. paracasei and Lb. acidophilus ice cream. Partial replacement of inulin with apple fiber resulted in a significant darkening of the color of ice cream mixes. Depending on the type of bacteria used for fermentation, the addition of apple fiber decreased the value of the L* parameter. Ice cream mixes and ice cream with inulin and apple fiber were characterized by a high proportion of yellow. Partial replacement of inulin with apple fiber reduced the hardness of ice cream compared to inulin-only ice cream. Moreover, the panelists found that ice cream with inulin was characterized by a sweeter taste than ice cream with apple fiber. Moreover, the addition of apple fiber favorably increased the flavor and aroma perception of the mango-passion fruit. Therefore, the milk of Olkuska sheep could be successfully used for the production of symbiotic dairy ice cream.

The Bioaccessibility of Antioxidants in Black Currant Puree after High Hydrostatic Pressure Treatment.

The aim of the study was to investigate the effect of high-pressure processing (HPP) and thermal processing (TP) on the bioaccessibility of vitamin C and anthocyanins as well as changes in the antioxidant capacity (AC) using ABTS+• and DPPH• tests on blackcurrant (Ribes nigrum L.) puree during the steps in the digestive process. The puree was subjected to HPP at 200, 400, and 600 MPa for 5 min (room temperature) or TP at 85 °C for 10 min. The controls were untreated puree (P) and fruit crushed in a mortar (M). All the samples were digested in a static in vitro digestion model, including the mouth, stomach, and small intestine, and subjected to dialysis. The vitamin C, anthocyanin, and antioxidant capacity were monitored at each step of the digestion process. The potential bioaccessibility of the antioxidants studied was calculated in relation to the undigested sample. TP and HPP enabled a high content of vitamin C, anthocyanins, and AC to be maintained. After simulated digestion in the small intestine, a significant decrease was observed in the vitamin C and anthocyanins (approximately 98%) content. However, a high stability (approximately 70%) of both compounds was noted at the gastric stage. HPP and TP significantly affected the potential bioaccessibility of vitamin C and anthocyanins, although the bioaccessibility of both compounds in the samples treated using HPP was higher than when using TP. Moreover, the potential bioaccessibility of vitamin C after HPP treatment (400 and 600 MPa) was higher than the bioaccessibility calculated for the M and P control samples. TP and HPP treatment negatively affected anthocyanin bioaccessibility after dialysis. The most favorable pressure was 400 MPa, as it allowed maintaining the best antioxidant activity after digestion.

Use of Calcium Amino Acid Chelate in the Production of Acid-Curd Goat Cheese.

Amino acid chelates are a new group of compounds approved for food enrichment, however there is no previous research using calcium amino acid chelate to enrich goat's milk products. The purpose of this research was to evaluate the possibility of using calcium amino acid chelate to produce goat's acid-curd cheese. In this study, four types of acid-curd cheeses from goat's milk subjected to 85 °C/5 min treatment were produced: control cheeses-made from milk without calcium addition and cheeses from milk enriched with 30, 35 and 40 mg of Ca (in 100 g of milk) in the form of calcium amino acid chelate. Goat cheese with calcium amino acid chelate had a higher moisture content, and a lower fat content. More fat was separated with the whey. In cheeses made from the milk with calcium amino acid chelate there was no goaty taste. Enrichment with 35 mg of Ca in 100 g of goat milk increased the calcium content in cheese by 60.5% in comparison to the control sample. However, the enrichment of goat milk with 40 mg Ca (in 100 g of processed milk) increased the calcium content in cheese by only 63.29%.

Liberation and Micellarization of Carotenoids from Different Smoothies after Thermal and Ultrasound Treatments.

The consumption of a varied diet rich in fruit and vegetables helps prevent and treat certain chronic diseases. The development of smoothies based on derivatives from fruit and vegetables rich in bioactive compounds can help increase the consumption of these foods, and therefore, contribute to the prevention of various health problems. However, during the processing of the fruit and vegetable smoothies, these properties may change. The elaboration of smoothies is based on fruits and vegetables rich in carotenoids: Carrot juice-papaya-mango (smoothie A) and carrot juice-pumpkin-mango (smoothie B). The objective of this study is to evaluate the impact of the application of different thermal technologies (mild and intensive heat treatment) and non-conventional technologies (ultrasound) on carotenoids (α-carotene, ß-carotene, lutein and ß-cryptoxantin) and determine the physiochemical parameters of derivatives from fruit and vegetable smoothies. In addition, the bioaccessibility of carotenoids is also evaluated through a process of in vitro simulated digestion. With regard to the bioaccessibility of the fruit and vegetable smoothies analyzed, a positive effect of temperature on liberation and micellarization was observed.

Bioaccessibility of bioactive compounds after non-thermal processing of an exotic fruit juice blend sweetened with Stevia rebaudiana.

A comparative study of the bioaccessibility of bioactive compounds and antioxidant capacity in a fruit juice-Stevia rebaudiana mixture processed by pulsed electric fields (PEF), high voltage electrical discharges (HVED) and ultrasound (USN) technology at two equivalent energy inputs (32-256kJ/kg) was made using an in vitro model. Ascorbic acid was not detected following intestinal digestion, while HVED, PEF and USN treatments increased total carotenoid bioaccessibility. HVED at an energy input of 32kJ/kg improved bioaccessibility of phenolic compounds (34.2%), anthocyanins (31.0%) and antioxidant capacity (35.8%, 29.1%, 31.9%, for TEAC, ORAC and DPPH assay, respectively) compared to untreated sample. This was also observed for PEF treated samples at an energy input of 256kJ/kg (37.0%, 15.6%, 29.4%, 26.5%, 23.5% for phenolics, anthocyanins, and antioxidant capacity using TEAC, ORAC and DPPH method, respectively). Consequently, pulsed electric technologies (HVED and PEF) show good prospects for enhanced bioaccessibility of compounds with putative health benefit.

Effect of Stevia rebaudiana addition on bioaccessibility of bioactive compounds and antioxidant activity of beverages based on exotic fruits mixed with oat following simulated human digestion.

In order to determine the impact of Stevia rebaudiana (SR) addition on bioactive compounds bioaccessibility of a new developed functional beverage based on exotic fruits (mango juice, papaya juice and açaí) mixed with orange juice and oat, an in vitro gastrointestinal digestion was performed. Ascorbic acid, total carotenoids, total phenolics, total anthocyanins, total antioxidant capacity and steviol glycosides were evaluated before and after a simulated gastrointestinal digestion. Salivary and gastric digestion had no substantial effect on any of the major phenolic compounds, ascorbic acid, total antioxidant capacity and steviol glycosides, whereas carotenoids and anthocyanins diminished significantly during the gastric step. All analysed compounds were significantly altered during the pancreatic-bile digestion and this effect was more marked for carotenoids and total anthocyanins. However, phenolic compounds, anthocyanins, total antioxidant capacity and steviol glycosides bioaccessibility increased as did SR concentration. Ascorbic acid bioaccessibility was negatively affected by the SR addition.

Analytical Methods for Determining Bioavailability and Bioaccessibility of Bioactive Compounds from Fruits and Vegetables: A Review.

Determination of bioactive compounds content directly from foodstuff is not enough for the prediction of potential in vivo effects, as metabolites reaching the blood system may be different from the original compounds found in food, as a result of an intensive metabolism that takes place during absorption. Nutritional efficacy of food products may be ensured by the determination of bioaccessibility, which provides valuable information in order to select the appropriate dosage and source of food matrices. However, between all the methods available, there is a need to establish the best approach for the assessment of specific compounds. Comparison between in vivo and in vitro procedures used to determine bioaccessibility and bioavailability is carried out, taking into account the strengths and limitations of each experimental technique, along with an intensive description of actual approaches applied to assess bioaccessibility of bioactive compounds. Applications of these methods for specific bioactive compound's bioaccessibility or bioavailability are also discussed, considering studies regarding the bioavailability of carotenoids, polyphenolic compounds, glucosinolates, vitamin E, and phytosterols.