Comparative study of the synbiotic effect of inulin and fructooligosaccharide with probiotics with regard to the various properties of fermented soy milk

Numerous combinations of probiotics were explored to find the suitable starter culture for the development of synbiotic soy yoghurt which can give good product characteristics and may be acceptable among consumers. Prebiotics (fructooligosaccharide (FOS) and inulin) were supplemented in an attempt to reduce the after-taste of soymilk, improve acidification profile and growth of probiotics. The addition of prebiotics in soy milk significantly enhanced the acidification rate (10.82 to 23.00 × 10^-3 pH units/min) and condensed the fermentation completion time. FOS-supplemented fermented soy milk showed better acidification and post-acidification profile as compared to inulin supplemented samples. The Streptococcus salivarius subsp. thermophilus (ST) - Lactobacillus acidophilus (LA) with FOS gave the better textural properties with firmer gel (350.10), lower adhesiveness (-93.10) and springiness (0.92), higher gumminess (164.50) and average cohesiveness (0.47). FOS-supplemented ST-LA-fermented samples showed good gel characteristics with higher elastic modulus (1672.39 Pa), viscous modulus (416.41 Pa), complex modulus (1723.53 Pa), lower tan δ (14) and higher overall acceptability scores (7.40) on a 9-point hedonic scale. Developed synbiotic soy fermented milk showed more than the 9 log cfu/ml count throughout storage which is required for probiotic functional food.

Comparative analysis of thermal-assisted high pressure and thermally processed mango pulp: Influence of processing, packaging, and storage

Storage stability and shelf-life of mango pulp packed in three different packaging films and processed using an optimized thermal-assisted high pressure processing treatment 'HPP' (600 MPa/52 ℃/10 min) was analyzed during refrigerated (5 ℃) and accelerated (37 ℃) storage and compared with the conventional thermal treatment 'TT' (0.1 MPa/95 ℃/15 min). After processing, HPP resulted in relatively lower total color difference (3.5), retained higher ascorbic acid (95%), total phenolics (106%), total flavonoids content (118%) in mango pulp compared to TT, with values of 5.0, 62, 83, 73%, respectively. However, HPP led to ∼50% enzymes inactivation (pectin methylesterase, polyphenol oxidase, peroxidase) in comparison to >90% obtained during TT. Both HPP and TT resulted in > 5 log₁₀ units reduction of the studied microorganisms to give a safe product. In contrast to the refrigerated storage, quality changes under accelerated conditions were found to be considerably rapid and dependent on packaging material irrespective of the method of processing. Shelf-life under refrigeration was limited by microbial growth and sensory quality; whereas, browning restricted the shelf-life during accelerated storage. HPP in aluminum-based retort pouch was adjudged superior processing -packaging combination for maximizing the shelf-life of mango pulp to 120 and 58 days during refrigerated and accelerated storage, respectively. In comparison, TT led to higher quality changes upon processing than HPP and resulted in shelf-life of 110 and 58 days under the same packaging and storage conditions, respectively.

Twin screw extrusion of kodo millet-chickpea blend: process parameter optimization, physico-chemical and functional properties

Kodo millet-chickpea flour blend (70:30) was explored for development of directly expanded snack by twin-screw extrusion. Effect of process parameters like temperature (80-150 °C), screw speed (250-300 rpm) and feeder speed (15-30 rpm) on physical properties (expansion ratio, bulk density, hardness, crispiness) of extrudates were investigated and optimized using response surface methodology. Desirable crispy extrudates were obtained at higher screw speed 293 rpm, lower feeder speed 19 rpm, and medium to high temperature of 123 °C. Effect of extreme and intermediate process conditions on functional, proximate quality and colour of the extrudates were also evaluated.

High-Pressure Inactivation of Enzymes: A Review on Its Recent Applications on Fruit Purees and Juices

In the last 2 decades high-pressure processing (HPP) has established itself as one of the most suitable nonthermal technologies applied to fruit products for the extension of shelf-life. Several oxidative and pectic enzymes are responsible for deterioration in color, flavor, and texture in fruit purees and juices (FP&J). The effect of HPP on the activities of polyphenoloxidase, peroxidase, β-glucosidase, pectinmethylesterase, polygalacturonase, lipoxygenase, amylase, and hydroperoxide lyase specific to FP&J have been studied by several researchers. In most of the cases, partial inactivation of the target enzymes was possible under the experimental domain, although their pressure sensitivity largely depended on the origin and their microenvironmental condition. The variable sensitivity of different enzymes also reflects on their kinetics. Several empirical models have been established to describe the kinetics of an enzyme specific to a FP&J. The scientific literature in the last decade illustrating the effects of HPP on enzymes in FP&J, enzymatic action on those products, mechanism of enzyme inactivation during high pressure, their inactivation kinetics, and several intrinsic and extrinsic factors influencing the efficacy of HPP is critically reviewed in this article. In addition, process optimization of HPP targeting specific enzymes is of great interest from an industrial approach. This review will give a fair idea about the target enzymes specific to FP&J and the optimum conditions needed to achieve sufficient inactivation during HPP treatment.

Quantum-chemical (DFT, MP2) and spectroscopic studies (FT-IR and UV) of monomeric and dimeric structures of 2(3H)-Benzothiazolone

Molecular geometry and vibrational wavenumbers of 2(3H)-Benzothiazolone (C7H5NSO, HBT) was investigated using density functional (DFT/B3LYP) method with 6-311+G(d,p) basis set. The vibrational wavenumbers are found to be in good agreement with experimental FT-IR spectra. Hydrogen-bonded dimer of HBT, optimized by counterpoise correction, was studied by MP2 and DFT/B3LYP at the 6-311+G(d,p) level and the effects of molecular association through NH---O hydrogen bonding were discussed. A detailed analysis of the nature of the hydrogen bonding, using topological parameters, such as electronic charge density, Laplacian, kinetic and potential energy density evaluated at bond critical points (BCP) has also been presented. The UV absorption spectra of the compound dissolved in ethanol and chloroform solutions were recorded in the range of 200-600 nm. The UV-vis spectrum of the title molecule was also calculated using TD-DFT method. The calculated energy and oscillator strength almost exactly reproduce the experimental data. Total and partial density of state (TDOS, PDOS) of the HBT in terms of HOMOs and LUMOs and molecular electrostatic potential (MEP) were calculated and analyzed. The electric dipole moment, polarizability and the first static hyper-polarizability values for HBT were calculated at the DFT/B3LYP with 6-311+G(d,p) basis set. The results also show that the HBT molecule may have nonlinear optical (NLO) comportment with non-zero values. Stability of the molecule arising from hyper-conjugative interactions and charge delocalization was analyzed using natural bond orbital (NBO) analysis.

Microwave drying for safe storage and improved nutritional quality of green gram seed (Vigna radiata)

The present study describes the effect of the microwave-heating method on disinfestations and physico characteristics, viz., grain size, grain hardness, and nutritional quality, of the stored green gram seed. It has been observed that the use of the microwave-heating method not only prolongs the storage duration of the green gram seed but also enhances its nutritional quality. The effect of independent parameters, viz., microwave power level and time of exposure, on the moisture content, insect mortality, color, and antinutrient factor (phyic acid) was optimized using response surface methodology (RSM), with the optimized value for power of 808 W and time at 80 s. The optimally treated green gram seed has 8.9% moisture, 99.5% insect mortality, 2.22 Δa* (green color of seed), and 591.79 mg/100 g of antinutrient factor (phytic acid). The grain size (geometric mean diameter, D(m)) of the control (untreated) sample was 3.75 mm, and that of the microwave-treated sample using optimum conditions was 3.99 mm. The grain hardness of the control sample was 3.31 kg, and that of the microwave-treated sample using optimum conditions was 1.305 kg. In vitro protein digestibility (IVPD) of the control (untreated) sample was 83 ± 0.289%, and that of the microwave-treated sample using optimum conditions was 85 ± 0.296%. These values are significantly difference (p < 0.05). The mineral elements studied were Zn, Fe, Mg, Mn, Cu, K, Ca, and Na. The microwave treatment resulted in a non-significant (p < 0.05) effect for Mg, Mn, Cu, K, and Na but a significant (p < 0.05) effect for Zn, Ca, and Fe. The results indicate that the microwave heating not only increases the insect mortality but also reduces the moisture content and antinutritional factor (phytic acid), while the natural green color of the seed is not affected much. This study provides a novel and environmentally safe technique and increase in the nutritive quality.

A review on biological control and metabolism of aflatoxin

The series of events that led to the discovery of aflatoxin as a potent carcinogen, its biosynthesis, mechanism of action, structure-function relationship provide interesting insight into the economical and technological factors involved in the development of an effective control measure for the toxin. Scientists all over the world are making continuous efforts to explore a generalized process of detoxification, which can bring down the toxin content in heterogenous commodities to a threshold level. In this article biological control methods with special emphasis on in vivo and in vitro enzymatic detoxification of aflatoxin have been reviewed. Future areas of research involving large-scale enzymatic detoxification and modified atmosphere storage are also discussed.