Volume 13, Issue 9 -

In the present study, the effect of different polymerization degree of inulin on the quality parameters of conventional and sugar-free dark chocolate products as well as on the vitality of probiotics used in the chocolates were investigated. To produce sugar-free dark chocolates prepared with the addition of maltitol, Lactobacillus paracasei / L. acidophilus and inulin with DP higher than 23 and lower than 10 were used as probiotic and prebiotic agents, respectively. After 90 day of storage, more than 6 log cfu/25 g probiotics were observed in the chocolates produced by supplementing of 9 log cfu/25 g probiotics. Considering the probiotic level for both conventional and sugar-free dark chocolate, the highest probiotic level was observed in the samples prepared from L. acidophilus and inulin with DP<10. In addition, inulin with DP<10 was found as more suitable in terms of rheological characteristics of the samples. Other quality parameters (texture, colour, melting profile and water activity) changed in narrow range which was allowable when compared with the control samples. Consequently, sugar-free chocolate containing L. paracasei and L. acidophilus could be produced which might satisfy the expectations of the consumers and appropriate to industrial production similar to conventional chocolate. The findings of the present study highlighted the importance of the selection of the most suitable prebiotic/probiotic combination for maximizing probiotic level in the chocolate products.

The effects of ultrasonication on the physicochemical properties of bovine serum albumin (BSA)–glucose and the galactose conjugates formed by glycation was investigated. Fourier transform ion cyclotron resonance mass spectra analysis showed that the conjugates had a higher molecular weight than the native and ultrasonicated BSA. Ultrasonicated BSA had significantly higher emulsifying and foaming properties than native BSA. The browning intensity, surface hydrophobicity, emulsifying property and foaming capacity of the conjugates were substantially improved while the free amino groups, intrinsic fluorescence emission and foaming stability were decreased compared to native and ultrasonicated BSA. The results of this study indicate that ultrasonication is an efficient technique to improve the physicochemical properties of proteins. The glycation between ultrasonicated BSA and monosaccharide can effectively improve the physicochemical properties of BSA, and the glycation rate order is galactose \gt glucose. It also shows the critical role of monosaccharide conformational changes in improving the glycation and physicochemical properties of proteins.

Deacidification is one of the key steps in oil-refining processes. This study reported a simple approach for upgrading high-acid adlay bran oil by supercritical carbon dioxide (SC-CO 2 ) extraction. The high-acid adlay bran oil was obtained by three-stage countercurrent ethanol extraction of adlay bran, with high free fatty acids (34 % FFAs). The FFA content in adlay bran oil reduced to 10.6 % by SC-CO 2 extraction under optimized conditions. Interestingly, the SC-CO 2 deacidification process also markedly reduced oil color value from 11.5 (Red) to 0.3 (Red) and acetone-insoluble matters in the oil from 1.56 % to 0.17 %. The results indicated solvent extraction combined with SC-CO 2 deacidification method could be a feasible approach to significantly upgrade high-acid adlay bran oil and simplify refining process of adlay bran oil.

Drying plays an important role in post-harvest handling of onion for prolonging storage time. This research focuses on the drying studies of red onion bulbs using dehumidified air. The works were carried out by observing the microscopic structure of red onion bulbs layer and followed by developing mass transfer model for moisture diffusion during drying. Moisture diffusivity was estimated from drying experiments conducted at various temperatures (40, 50 and 60 °C) using the unsteady state solutions of Fick’s second law model. The diffusivity values were used to predict the drying kinetics as well as effective drying time for different air relative humidity. Results showed that combination of low relative humidity and low drying temperature significantly improved drying rate and reduced drying time.

The purpose of this study is to elucidate the water dynamics in sea cucumber ( Stichopus japonicas ) during drying process in situ by the fast and non-destructive low field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) methods. T 2 relaxation spectra in three-dimensional (3D) color map surface image from LF-NMR showed three main peaks assigned to bound water with relaxation time less than 2 ms, immobilized water in the range of 15–150 ms and extra-collagen fibrillar bulk water or free water adhered onto the sea cucumber with the longest relaxation time 200–1600 ms. The water dynamics in sea cucumber during drying process was clearly observed from the 3D color map surface image. Significant correlations between the LF-NMR T 2 parameters ( A Total , A 23 and T 23 ) and TPA parameters were observed, demonstrating that LF-NMR might be a complementary technique in monitoring the textural properties of sea cucumber during drying process.

Effects of adding antioxidant flaxseed peptides (FP) on rheological properties of native maize starch (NMS) were investigated using temperature sweep and frequency sweep tests. The NMS concentration of 15 % (w/w) and FP concentrations of 0.2–1.0 % (w/w) were used. The FP samples were prepared by controlled hydrolysis flaxseed protein isolate with pepsin. The highest DPPH radical scavenging activity (53.25 %) was achieved at 22 % of hydrolysis. The onset gelatinization temperature ( T onset ) increased from 67°C to 76°C when the 1 % FP was present in the NMS–FP mixture. The storage modulus ( G′ ) decreased significantly in the presence and increased in concentration of FP. The variation of G′ and loss modulus ( G″ ) of NMS–FP mixtures with angular frequency was fitted well ( R 2 >0.97) Power law type models. The consistency coefficient ( K′ and K″ ) decreased in the presence and increased in the concentration of FP. While the n′ increased with the presence FP, the n″ decreased. The NMS–FP mixtures produced physical gels ( G′ > G″ ). NMS-FP mixtures showed non-Newtonian shear thinning behavior in steady shear flow.

Liposomes could be employed to improve the absorption of iron. The purpose of this study was to estimate the intestinal permeability of ferrous glycinate liposomes and to assess the effects of phytic acid, zinc and particle size on iron absorption using in situ single-pass perfusion in rats. The results showed that the absorption of ferrous glycinate liposomes was obviously higher than that of ferrous glycinate. The inhibitory effects of phytic acid and zinc on iron absorption were reduced by incorporating ferrous glycinate into liposomes. The particle size of ferrous glycinate liposomes was also a main factor for affecting iron absorption, and the intestinal permeability of the liposomes decreased with its particle size increasing. The results suggested that liposomes could be a potent delivery system to decrease the inhibitory effects of phytic acid and zinc and to enhance iron absorption. Furthermore, liposomes could alter the absorption pathways of ferrous glycinate.

The allergens absorbed in immunoreactive form by the gut epithelium might induce the occurrence of allergy. The purpose of this study was to investigate the absorption and intracellular accumulation of the intact or hydrolyzed glycinin in the porcine intestinal epithelial cells (IPEC-J2). The IPEC-J2 cells were incubated by 0, 0.25, 0.5 and 1.0 mg/mL glycinin or its hydrolysate for 2, 4, 8 or 12 h. The amounts of immunoreactive glycinin were measured by enzyme-linked immunosorbent assay. The intact and hydrolyzed glycinin fragments of epithelial absorption were identified by immunoblotting and mass spectrometry (MS). We found that glycinin or its hydrolysate is expensively absorbed with the increase of dose and time. The 35 kD or 22 kD protein with glycinin-specific epitopes was detected in the intracellular extracts and basolateral solutions. The results indicate that the glycinin or its hydrolysate could be absorbed; meanwhile, the 35kD or 22kD protein was correspondingly produced during absorption.

Blackberry is highly appreciated for the enjoyable color and flavor. About 20 % of the pomace is generated in its processing and often unused, presenting potential use by the food industry. Thus, the present study aimed to microencapsulate extracts of the blackberry pomace applying spray dryer process. Pure extracts (aqueous and hydroalcoholic solution) and the encapsulating agent (maltodextrin DE 10), in a ratio of 1:1 (w/w), were spray dried and analyzed for total anthocyanins, antioxidant activity, phenolics, HPLC-DAD chromatography, instrumental color and scanning electron microscopy. Hydroalcoholic extraction was more efficient (1.5 times) for anthocyanins encapsulation than aqueous extraction. However, for phenolic compounds the highest efficiency (1.2 times) was in the aqueous solution. The majority bioactive compounds were gallic acid and cyanidin. Considering that water is a low cost and ecofriendly solvent, it is indicated this type of extraction to obtain microcapsules of blackberry pomace mainly for future applications by food industry.

To develop a structurally simple and easy-to-use viscometer for liquid foods, flow measurements and analyses were done in a flow channel instrument. Newtonian and non-Newtonian test liquids respectively employed in the experiments show viscosity and viscoelasticity. Changes of the modified friction coefficient during the flow processes characterized viscous flow in the instrument. The elasticity was found to be dominant in the early process, reducing the flow as a function of the relative magnitude of liquid viscoelasticity.