Effect of microwave drying and tempering on color attributes, fissure formation, and cooking characteristics of fortified rice kernels.

Fortified rice kernels (FRK) are a vitamin-mineral enriched extruded rice-shaped product blended with raw or parboiled rice in a 1:100 ratio to prepare fortified rice. In FRK manufacturing, drying is one of the essential steps that affect the quality of FRK. In the present study, the microwave technique was explored to dry FRK continuously at 180, 360, and 540 W and with the tempering (1, 2, and 3 min) at 180 W to evaluate the effects on the drying curves, color attributes, fissure formation, and cooking characteristics. Thin layer modeling suggested the Two-term exponential model (two parameters), diffusion model (three parameters), and Midilli Kucuk (four parameters) as the best models to predict moisture based on Akaike and Bayesian information criteria. The higher MWP (360 and 540 W) significantly lowered the L* and WI while increasing the a*, b*, and BI compared to 180 W, which was undesirable. Image processing showed fissures in all FRK samples; however, 1 min and 2 min tempering could somewhat restrict the fissure. The fissures caused higher solid losses and increased splitting of kernels during cooking. It can be concluded that the low MWP (< 180W) with appropriate tempering time can be used to dry FRK. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05871-4.

Amelioration of the stability of polyunsaturated fatty acids and bioactive enriched vegetable oil: blending, encapsulation, and its application.

Lipid oxidation in vegetable oils is the primary concern for food technologists. Modification of oils like hydrogenation, fractionation, inter-esterification, and blending are followed to improve nutritional quality. Blending non-conventional/conventional vegetable oils to obtain a synergistic oil mixture is commonly practiced in the food industry to enhance the nutritional characteristics and stability of oil at an affordable price. Microencapsulation of these oils provides a functional barrier of core and coating material from the adverse environmental conditions, thereby enhancing the oxidative stability, thermo-stability, shelf-life, and biological activity of oils. Microencapsulation of oils has been conducted and commercialized by employing different conventional methods including emulsification, spray-drying, freeze-drying, coacervation, and melt-extrusion compared with new, improved methods like microwave drying, spray chilling, and co-extrusion. The microencapsulated oil emulsion can be either dried to easy-to-handle solids/microcapsules, converted into soft solids, or enclosed in a gel-like matrix, increasing the shelf-life of the liquid oil. The omega-rich microcapsules have a wide application in confectionery, dairy, ice-cream, and pharmaceutical industries. This review summarizes recent developments in blending and microencapsulation technologies in improving the stability and nutritional value of edible oils.

Development of grain-based carbonated beverage premix using maize (Zea Mays), Bengal gram (Cicer Arietinum), and finger millet (Eleusine Coracana).

A grain based carbonated beverage premix with adequate nutritional composition and fizzing effect in the form of dry powder has been developed in the current study. Maize and Bengal gram were roasted at temperature 160-180 °C while finger millet at 80-120 °C for 10-30 min. The optimized conditions for the roasting of maize, Bengal gram and finger millet were 180 °C for 10 min, 180 °C for 27 min and 110 °C for 30 min, respectively using face centred composite design and response surface methodology (RSM). The formulation of the beverage premix obtained using linear programming was in the proportion of 30 g, 30 g, 10 g, 20 g and 10 g of roasted maize, Bengal gram, finger millet flours, sugar (powdered) and pea protein isolate, respectively. The effect of carbonation was found to be best with 8% carbonation powder concentration and 1:4 beverage premix to water ratio which showed an overall acceptability of 7.7. The developed carbonated beverage premix was light in color with a positive L* value of 79.01 ± 0.12 and slightly acidic with a pH of 5.56 ± 0.10. The nutritional composition of the final product comprised of 16% protein and several minerals viz. Fe (11.67 mg/100 g), Ca (36.67 mg/100 g) and Mg (86.26 mg/100 g). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13197-021-05175-5.

Effect of hydrocolloids on the physico-chemical and rheological properties of reconstituted sweetened yoghurt powder.

BACKGROUND: The consistency of sweetened yoghurt (misti dahi) is a desired characteristic which is attributed to the casein protein network formation during fermentation. Unfortunately, this property is lost in reconstituted sweetened yoghurt (RSY) due to the irreversible nature of protein denaturation during spray drying. Therefore, this study aimed to increase the consistency of RSY using different hydrocolloids. RESULTS: The effects addition of guar gum, pectin, κ-carrageenan and gelatin (0.1%w/v each) on the physico-chemical, microbial, rheological and sensory properties of RSY were investigated. RSY with 40% total solids demonstrated the rheological properties which are very similar to those of fresh sweetened yoghurt. RSY containing different hydrocolloids further increased the rheological properties. The dynamic rheological study revealed that the magnitude of storage modulus (G'), loss modulus (G″), and loss tangent (tan δ) were significantly influenced by the addition of hydrocolloids and gelatin exhibited highest dynamic moduli in RSY. However, κ-carrageenan added RSY was preferred sensorially as the rheological properties were very close to gelatin added RSY. Addition of hydrocolloids significantly increased the starter bacteria count and pH and reduced water expulsion rate (P < 0.05). CONCLUSION: Addition of hydrocolloids can improve the rheological properties of reconstituted yoghurt. The study concluded that the addition of κ-carrageenan showed better results in terms of rheological and sensory properties of RSY. © 2017 Society of Chemical Industry.

Thermodynamics of sorption isotherms and storage stability of spray dried sweetened yoghurt powder.

Sorption isotherm is a quantitative approach to predict the shelf life of dried foods. Adsorption isotherms of spray dried sweetened yoghurt powder (SYP) were determined by static gravimetric technique at 20, 30, 40 and 50 °C. The data obtained were fitted to eight different sorption models. A non-linear least square regression analysis was adopted to evaluate the model constants. The experimental sorption data were best fitted to four parameter Peleg model. The monolayer moisture contents found from GAB model were 4.88, 4.54, 3.86 and 3.52% at 20, 30, 40 and 50 °C, respectively. The maximum net isosteric heat of sorption and sorption entropy of SYP were 9.399 kJ/mol and 20.28 J/mol K, respectively. The Gibb's free energy change for sorption was in the range 3436.19-303.91 J/mol. The storage stability in terms of moisture content, thiobarbituric acid, free fatty acid, hydroxymethyl furfural values and starter counts of SYP packed in aluminium laminated polyethylene (ALPE) and low density polyethylene (LDPE) were studied along with their change kinetics. The relationship between the water vapour permeability of packaging materials and adsorbed moisture (determined from GAB equation) in powder was used to predict the shelf life and was predicted as 28 and 44.44 days in LDPE and ALPE pouches, respectively.

Optimization of microwave roasting of peanuts and evaluation of its physicochemical and sensory attributes.

In this study, the microwave (MW) roasting (MWR) of peanuts (Arachis hypogaea L.) is attempted, optimized and compared with conventional drum roasting. A two factor/three level face centered composite design based MWR experiments was conducted at different roasting time (60, 180 and 300 s) and MW power levels (180, 540 and 900 W). The roasting quality was analyzed by physicochemical and sensory attributes of roasted peanuts and extracted oil viz., moisture loss, hardness, browning index (BI), induction period (IP) based on Rancimat, peroxide value (PV) and overall acceptability (OA), respectively. A roasting time and MW power dependent improvement in the desired quality of roasted peanuts and extracted oil was observed attributable to the formation of antioxidant Maillard reaction compounds. A second order polynomial model adequately described the roasting experimental data (p < 0.0001, R2 > 0.90) with an insignificant lack of fit (p > 0.05). Using response surface methodology, the MWR was optimized at roasting time of 201 s and MW power level of 900 W which yielded favorable values of quality attributes (moisture loss, 3.06%; hardness, 4528.34 g; BI, 58.89; IP, 8.12 h; PV, 8.80 milliequivalents O2/kg; OA, 6.40). Furthermore, the quality assessment of ground peanuts for selected time-power combinations (low, optimum and high roasts) was attempted using scanning electron microscopy, electronic nose and Fourier transform infrared spectroscopy which revealed better quality of optimized MWR peanuts.

Multivariate optimization of a synergistic blend of oleoresin sage (Salvia officinalis L.) and ascorbyl palmitate to stabilize sunflower oil.

The simultaneous optimization of a synergistic blend of oleoresin sage (SAG) and ascorbyl palmitate (AP) in sunflower oil (SO) was performed using central composite and rotatable design coupled with principal component analysis (PCA) and response surface methodology (RSM). The physicochemical parameters viz., peroxide value, anisidine value, free fatty acids, induction period, total polar matter, antioxidant capacity and conjugated diene value were considered as response variables. PCA reduced the original set of correlated responses to few uncorrelated principal components (PC). The PC1 (eigen value, 5.78; data variance explained, 82.53 %) was selected for optimization using RSM. The quadratic model adequately described the data (R (2) = 0. 91, p < 0.05) and lack of fit was insignificant (p > 0.05). The contour plot of PC 1 score indicated the optimal synergistic combination of 1289.19 and 218.06 ppm for SAG and AP, respectively. This combination of SAG and AP resulted in shelf life of 320 days at 25 °C estimated using linear shelf life prediction model. In conclusion, the versatility of PCA-RSM approach has resulted in an easy interpretation in multiple response optimizations. This approach can be considered as a useful guide to develop new oil blends stabilized with food additives from natural sources.

Functionality of alternative protein in gluten-free product development.

Celiac disease is an immune-mediated disease triggered in genetically susceptible individuals by ingested gluten from wheat, rye, barley, and other closely related cereal grains. The current treatment for celiac disease is life-long adherence to a strict gluten-exclusion diet. The replacement of gluten presents a significant technological challenge, as it is an essential structure-building protein, which is necessary for formulating high-quality baked goods. A major limitation in the production of gluten-free products is the lack of protein functionality in non-wheat cereals. Additionally, commercial gluten-free mixes usually contain only carbohydrates, which may significantly limit the amount of protein in the diet. In the recent past, various approaches are attempted to incorporate protein-based ingredients and to modify the functional properties for gluten-free product development. This review aims to the highlight functionality of the alternative protein-based ingredients, which can be utilized for gluten-free product development both functionally as well as nutritionally.

Thin-layer modeling of convective and microwave-convective drying of oyster mushroom (Pleurotus ostreatus).

Oyster mushroom samples were dried under selected convective, microwave-convective drying conditions in a recirculatory hot-air dryer and microwave assisted hot-air dryer (2.45 GHz, 1.5 kW) respectively. Only falling rate period and no constant rate period, was exhibited in both the drying technique. The experimental moisture loss data were fitted to selected semi-theoretical thin-layer drying equations. The mathematical models were compared according to three statistical parameters, i.e. correlation coefficient, reduced chi-square and residual mean sum of squares. Among all the models, Midilli et al. model was found to have the best fit as suggested by 0.99 of square correlation coefficient, 0.000043 of reduced-chi square and 0.0023 of residual sum of square. The highest effective moisture diffusivity varying from 10.16 × 10(-8) to 16.18 × 10(-8) m(2)/s over the temperature range was observed in microwave-convective drying at an air velocity of 1.5 m/s and the activation energy was calculated to be 16.95 kJ/mol. The above findings can aid to select the most suitable operating conditions, so as to design drying equipment accordingly.

Apparent amylose content positively influences the quality of extruded fortified rice kernels.

The present research studies the impact of apparent amylose content (AAC) on the quality of fortified rice kernels (FRK), a health food designed to combat iron deficiency anemia by fortifying with iron, folic acid, and vitamin B12. Five FRK formulations with varying AAC (0.46-23.89 %) were prepared, and AAC influence on the extruder-system parameter and physicochemical, cooking, and textural properties of FRK was investigated. The torque, die-pressure, length, redness, and cooking time increased with an increase in AAC and were in the range of 12.55-22.81 Nm, 58.31-88.96 bar, 4.58-5.09 mm, 0.35-1.15, and 6.1-11.2 min, respectively. The other parameters, such as the breadth, whiteness index, and cooking loss decreased with an increase in AAC. Except for cohesiveness, all other textural properties of cooked FRK increased with an increase in AAC. These correlations of the FRK properties with AAC were confirmed through multivariate analysis. SEM, XRD, FTIR, and rheology supported the observed AAC trends in FRK properties. SEM showed a reduction in pores and cracks with an increase in AAC. The XRD and FTIR showed an increase in crystallinity with an increase in AAC due to better gelatinization leading to rapid retrogradation. This leads to better physical, cooking, and textural properties of FRK.

A comprehensive review of the spoilage of shrimp and advances in various indicators/sensors for shrimp spoilage monitoring.

Shrimp is a popular internationally traded shellfish due to its unique taste, texture, and nutritional value. Shrimp is highly perishable because it has enough free amino acids, high moisture levels, non-nitrogenous compounds used for microbial growth, and melanosis. Shrimp spoilage after death is caused by various reasons, like autolysis (endogenous proteinases actions during shrimp storage), growth of spoilage microorganisms, ATP degradation, melanin formation, and lipid peroxidation. A microbial byproduct, total volatile basic nitrogen, is one of the major reasons for the generation of foul odors from shrimp spoilage. Shrimp freshness monitoring is crucial for market sellers and exporters. Traditional methods for estimating shrimp freshness are expensive and inaccessible to the general public. Sensors are rapid, sensitive, selective, and portable food toxins' detection tools, devoid of expensive instruments, skilled people, sample pretreatment, and a long detection time. This review addresses shrimp spoilage causes. The mechanisms of different stages of shrimp spoilage after death, like rigor mortis, dissolution of rigor mortis, autolysis, and microbial spoilage mechanisms, are discussed. This review highlights the last five years' advances in shrimp freshness detection sensors and indicators like colorimetric pH indicators, fluorescence sensors, electronic noses, and biosensors, their working principles, and their sensitivities. Commercially available indicators and sensors for shrimp spoilage monitoring are also discussed. A review highlighting the applications of the different sensors and indicators for monitoring shrimp freshness is unavailable to date. Challenges and future perspectives in this field are explained at the end.

Probiotication in multigrain dough and biscuits with the incorporation of erythritol: Evaluation of techno-functional properties using chemometric approach.

This study aims to develop a multigrain probiotic biscuit and evaluate the effect of erythritol as a sugar replacer on the rheological properties of dough, along with the physicochemical and organoleptic properties of biscuits. The higher viscoelasticity of dough was observed at a 25% sugar replacement level with erythritol, and the calorific value of biscuits was significantly (p < 0.05) reduced from 415.12 to 404.69 Cal/100 g with increasing in the sugar replacement from 0% to 75%. The biscuits with higher concentrations of erythritol showed reduced water activity (aw) and higher hardness values. From Pearson's correlation analysis, it was observed that the probiotic viability had a positive relation with moisture, fat, energy, aw, and diameter and a negative association with the protein and fiber content of biscuits. The 25% replacement of sugar with erythritol showed a higher probiotic count (> 7 log CFU/g) and improved physicochemical and sensory properties during the storage period, which was further confirmed by the principal component analysis. So, it was recommended that the partial replacement of sugar with erythritol up to 25% is desirable for developing low-calorie bakery products without any alteration in the functional groups and improving the internal structure of the biscuits.

Effect of Marjoram Leaf Powder Addition on Nutritional, Rheological, Textural, Structural, and Sensorial Properties of Extruded Rice Noodles.

Food-to-food fortification is an emerging technique to enrich the micronutrients in foods. Pertaining to this technique, noodles could also be fortified with natural fortificants. In this study, marjoram leaf powder (MLP) at a level of 2-10% was used as a natural fortificant to produce fortified rice noodles (FRNs) through an extrusion process. The MLP addition caused a significant increase in the iron, calcium, protein, and fiber in the FRNs. The noodles had a lower whiteness index than unfortified noodles but had a similar water absorption index. The water solubility index increased significantly due to the higher water retention ability of MLP. A rheological study showed a minimal effect of fortification on the gelling strength of the FRNs at lower levels. The microstructural studies found incremental cracks, which facilitated a lower cooking time and hardness but had an insignificant effect on the cooked noodle texture. Fortification improved the total phenolic content, antioxidant capacity, and total flavonoid content. However, no significant changes in bonds were observed, but a reduction in the noodles' crystallinity could be seen. The sensory analysis of the noodles reflected a higher acceptability of the 2-4% MLP fortified samples compared to the others. Overall, the MLP addition improved the nutritional content, antioxidant activity, and the cooking time but slightly affected the rheological, textural, and color properties of the noodles.

Emerging Technologies and Coating Materials for Improved Probiotication in Food Products: a Review.

From the past few decades, consumers' demand for probiotic-based functional and healthy food products is rising exponentially. Encapsulation is an emerging field to protect probiotics from unfavorable conditions and to deliver probiotics at the target place while maintaining the controlled release in the colon. Probiotics have been encapsulated for decades using different encapsulation methods to maintain their viability during processing, storage, and digestion and to give health benefits. This review focuses on novel microencapsulation techniques of probiotic bacteria including vacuum drying, microwave drying, spray freeze drying, fluidized bed drying, impinging aerosol technology, hybridization system, ultrasonication with their recent advancement, and characteristics of the commonly used polymers have been briefly discussed. Other than novel techniques, characterization of microcapsules along with their mechanism of release and stability have shown great interest recently in developing novel functional food products with synergetic effects, especially in COVID-19 outbreak. A thorough discussion of novel processing technologies and applications in food products with the incorporation of recent research works is the novelty and highlight of this review paper.

Incorporation of Mycelium (Pleurotus eryngii) in Pea Protein Based Low Moisture Meat Analogue: Effect on Its Physicochemical, Rehydration and Structural Properties.

The protein content of a plant-based ingredient is generally lower than its animal food counterpart, and research into novel alternative protein is required that can provide similar protein content, texture and appearance as meat. This work investigates a mycelium-based low moisture meat analogue (LMMA) approach, by incorporating 0 to 40% w/w mycelium (MY) into pea protein isolate (PPI) via extrusion using a twin-screw extruder at 140 °C die temperature, 40 rpm screw speed, and 10 rpm feeder speed (0.53-0.54 kg/h). Physicochemical, rehydration, and structural properties of LMMA were assessed. The MY incorporation led to a significant change in color attributes due to Maillard reaction during extrusion. Water solubility index and water absorption capacity increased significantly with MY addition, owing to its porous structure. Oil absorption capacity increased due to increased hydrophobic interactions post-extrusion. Protein solubility decreased initially (upto 20% w/w MY), and increased afterwards, while the water holding capacity (WHC) and volumetric expansion ratio (VER) of LMMA enhanced with MY addition upto 30% w/w. Conversely, WHC and VER decreased for 40% w/w which was verified with the microstructure and FTIR analysis. Overall, MY (30% w/w) in PPI produced a fibrous and porous LMMA, showing future potential with an increasingly plant-based product market and decreasing carbon footprint of food production activities.

Innovative Technologies for Extraction and Microencapsulation of Bioactives from Plant-Based Food Waste and their Applications in Functional Food Development.

The by-products generated from the processing of fruits and vegetables (F&V) largely are underutilized and discarded as organic waste. These organic wastes that include seeds, pulp, skin, rinds, etc., are potential sources of bioactive compounds that have health imparting benefits. The recovery of bioactive compounds from agro-waste by recycling them to generate functional food products is of increasing interest. However, the sensitivity of these compounds to external factors restricts their utility and bioavailability. In this regard, the current review analyses various emerging technologies for the extraction of bioactives from organic wastes. The review mainly aims to discuss the basic principle of extraction for extraction techniques viz. supercritical fluid extraction, subcritical water extraction, ultrasonic-assisted extraction, microwave-assisted extraction, and pulsed electric field extraction. It provides insights into the strengths of microencapsulation techniques adopted for protecting sensitive compounds. Additionally, it outlines the possible functional food products that could be developed by utilizing components of agricultural by-products. The valorization of wastes can be an effective driver for accomplishing food security goals.

Fuzzy controller based E-nose classification of Sitophilus oryzae infestation in stored rice grain.

Fuzzy controller artmap based algorithms via E-nose selective metal oxides sensor (MOS) data was applied for classification of S. oryzae infestation in rice grains. The screened defuzzified data of selective sensors was further applied to detect S. oryzae infested rice with PCA and MLR techniques. Reliability of data was cross validated with reference methods of protein and uric acid content. Out of 18 MOS, 6 sensors namely P30/2, P30/1, T30/1, P40/2, T70/2 and PA/2 showed maximum resistivity change. Defuzzified score of 62.17 for P30/2 and 59.33 for P30/1 MOS further confirmed validity studies of E-nose sensor response with reference methods. The PCA plots were able to classify up to 84.75% of rice with variable degree of S. oryzae infestation. The MLR values of predicted versus reference values of protein and uric acid content were found to be fitting with R2 of 0.972, 0.997 and RMSE values of 2.08, 1.05.

Kinetics of lipid oxidation in omega fatty acids rich blends of sunflower and sesame oils using Rancimat.

Blended sunflower (SO) (50-80%) and sesame oils (SEO) (20-50%) were evaluated for thermo-oxidative stability (induction period, IP), oxidation kinetics (rate constant, k), synergy and shelf-life (25 °C) (IP25) using Rancimat (100, 110, 120, and 130 °C). The Arrhenius equation (ln k vs. 1/T) and activated complex theory (ln k/T vs. 1/T) were used to estimate activation energies, activation enthalpies and entropies, which varied from 92.05 to 99.17 kJ/mol, 88.83 to 95.94 kJ/mol, -35.58 to -4.81 J/mol K, respectively (R2 > 0.90, p < 0.05). Oil blend (OB) with 1:1 SO to SEO exhibited greatest synergy (115%), highest IP (100 °C) (13.2 vs. 6.1 h) and most extended IP25 (193 vs. 110 days) with a nutritionally stable composition of ω-fatty acids (ω9, 34.5 vs. 28.7%; ω6, 49 vs. 52%) compared with SO. Better retention of lignans (6205 vs. 3951 mg/kg) and tocopherols (332 vs. 189 mg/kg) were also noted in OB compared with SO alone.

Identification and differentiation of insect infested rice grains varieties with FTNIR spectroscopy and hierarchical cluster analysis.

The potential and practicality of FTNIR as a screening tool, with ward's algorithms, was performed for two different varieties of rice namely, 'badshah bhog' and 'swarna', followed by cluster, dendrogram, histogram, and conformity analysis with different storage periods (0-225) and insect infestation. Dendrogram analysis resulted in a clear differentiation between infested rice varieties with non-infested ones while hierarchical cluster analysis, lead to detection of different levels of infestations. Histograms analysis of averaged FTINR spectra of rice grains samples provided 100% classification between infested and non-infested samples. Dissimilarities between rice grains were calculated using Pearson's correlation coefficients which were further converted to D values, and heterogeneity among the different varieties of rice along with a different level of infestation was identified. The results further revealed that the percentage accuracy (%) of classification for badshah bhog varied from 93.10 to 98.84%, while that for the swarna rice was between 95.75 and 99.74%.

Selection of the best active modified atmosphere packaging with ethylene and moisture scavengers to maintain quality of guava during low-temperature storage.

In modified atmosphere packaging of guava, moisture scavenger (MS) sachet containing 30-50 g of coarse silica gel and ethylene scavenger (ES) sachet containing 0-4 g of potassium permanganate was added as per central composite rotatable design. The headspace O2 and CO2 of the packages were studied at 4, 8 and 12 °C for 30 days and thereafter the guava were left for two days to ripen at 30 °C. After that the chilling injuries, percentage acceptable guava, peel color and pulp texture was analyzed. After two days ripening at 30 °C the samples with 3 g ES and 46 g MS registered higher L∗, lower a∗ value & firmness (16.65 N), lowest chilling injury score. About 95% of guava was found acceptable in this treatment with 1.89-2.79% reducing sugar, 0.95-1.1% titrable acidity, 59% and 46.61% retention of total phenols and ascorbic acid respectively, resulting 32 days shelf-life of guava.