Nondestructive testing methods for pesticide residue in food commodities: A review.

Pesticides play an important role in increasing the overall yield and productivity of agricultural foods by controlling pests, insects, and numerous plant-related diseases. However, the overuse of pesticides has resulted in pesticide contamination of food products and water bodies, as well as disruption of ecological and environmental systems. Global health authorities have set limits for pesticide residues in individual food products to ensure the availability of safe foods in the supply system and to assist farmers in developing the best agronomic practices for crop production. Therefore, the use of nondestructive testing (NDT) methods for pesticide residue detection is gaining interest in the food supply chain. The NDT techniques have several advantages, such as simultaneous measurement of chemical and physical characteristics of food without destroying the product. Although numerous studies have been conducted on NDT for pesticide residue in agro-food products, there are still challenges in real-time implementation. Further study on NDT methods is needed to establish their potential for supplementing existing methods, identifying mixed pesticides, and performing volumetric quantification (not surface accumulation alone).

Comparative assessment of blood glucose monitoring techniques: a review.

Monitoring blood glucose levels is a vital indicator of diabetes mellitus management. The mainstream techniques of glucometers are invasive, painful, expensive, intermittent, and time-consuming. The ever-increasing number of global diabetic patients urges the development of alternative non-invasive glucose monitoring techniques. Recent advances in electrochemical biosensors, biomaterials, wearable sensors, biomedical signal processing, and microfabrication technologies have led to significant research and ideas in elevating the patient's life quality. This review provides up-to-date information about the available technologies and compares the advantages and limitations of invasive and non-invasive monitoring techniques. The scope of measuring glucose concentration in other bio-fluids such as interstitial fluid (ISF), tears, saliva, and sweat are also discussed. The high accuracy level of invasive methods in measuring blood glucose concentrations gives them superiority over other methods due to lower average absolute error between the detected glucose concentration and reference values. Whereas minimally invasive, and non-invasive techniques have the advantages of continuous and pain-free monitoring. Various blood glucose monitoring techniques have been evaluated based on their correlation to blood, patient-friendly, time efficiency, cost efficiency, and accuracy. Finally, this review also compares the currently available glucose monitoring devices in the market.

Corn distillers solubles by two-step proteolytic hydrolysis as a new source of plant-based protein hydrolysates with ACE and DPP4 inhibition activities.

Proteins of low-value and underexplored corn distillers solubles (CDS) have not been considerably valorized. Hence, the influence of one-step enzymatic hydrolysis of proteins with alcalase (A), trypsin (T) or flavourzyme (F) and two steps with AT, TA, AF, FA, TF, or FT was assessed to release peptides with angiotensin-I converting enzyme inhibition (ACEi) and dipeptidyl peptidase4 inhibition (DPP4i). The AF hydrolysate was the best sample in terms of yield, protein content, degree of hydrolysis, ACEi (97.68 ± 1.09 %), and DPP4i (51.51 ± 0.28 %). Mass spectrometry of the most active AF hydrolysate (<3 kDa) identified new major peptides like APLA, PLFP, LFLP, LPPYL, PLYPLP, NDWHTGPL, LPPYLPS, GSPFLGQ, SWQQPIVGG. Bioinformatic analysis showed these can inhibit both ACE and DPP4. This is because peptides contain functional groups and adopt conformations significantly binding with other functional groups at enzyme active sites (p < 0.05). This establishes dual bioactivity of peptides, which may have applications in food, feed, and pharmaceutical industries.

Enhanced hydrophobic paper-sheet derived from Miscanthus × giganteus cellulose fibers coated with esterified lignin and cellulose acetate blend.

Biobased packaging materials derived from carbon-neutral feedstocks are sustainable alternatives to conventional fossil-based polymers. In this study, a method was developed to prepare paper-sheets derived from Miscanthus × giganteus cellulose fibers for potential food contact applications. The papers were hydrophobized with modified lignin from Miscanthus × giganteus biomass and commercial Kraft alkali lignin through hydroxyethylation with ethylene carbonate, followed by esterification with propionic acid. The esterified lignin (10 % w/w) and cellulose acetate (5 % w/w, based on lignin content) were dissolved in acetone and applied as a coating on the miscanthus paper sheets. The esterified lignins were characterized using FTIR, NMR, DSC, TGA, and elemental analyses. The uncoated and coated paper-sheets had contact angle values 52.4° and >130°, respectively, indicating an increased surface hydrophobicity of the coated paper samples. The water vapor transmission rate decreased significantly from 213.7 (uncoated paper-sheet) to 63.3 g/m2.d (coated paper-sheet). The tensile strength of the coated paper (64.6 MPa) was higher than the uncoated counterpart (57.1 MPa). Results from this study suggest that the esterified lignin coated miscanthus paper is a promising hydrophobic food packaging material alternative to conventional fossil-based thermoplastics.

Corn distillers solubles as a novel bioresource of bioactive peptides with ACE and DPP IV inhibition activity: characterization, in silico evaluation, and molecular docking.

This study aimed to investigate the biological potential of underutilized and low-value corn distillers solubles, containing a unique unexplored blend of heat-treated corn and yeast proteins, from the bioethanol industries, by bioinformatic and biochemical approaches. Protein hydrolysates were produced by applying four commercially accessible proteases, among which alcalase provided the best results in terms of yield, degree of hydrolysis, molecular weight, number of proteins, bioactive peptides, and deactivation against anti-angiotensin I-converting enzyme (ACE) and anti-dipeptidyl peptidase IV (DPP IV). The optimal conditions to produce anti-ACE and anti-DPP IV peptides were using alcalase for 10.82 h and an enzyme : substrate ratio of 7.90 (%w/w), with inhibition values for ACE and DPP IV of 98.76 ± 1.28% and 34.99 ± 1.44%, respectively. Corn (α-zein) and yeast (glyceraldehyde-3-phosphate dehydrogenase) proteins were mainly suitable, upon enzymolysis, for the release of bioactive peptides. The peptides DPANLPWG, FDFFDNIN, WNGPPGVF, and TPPFHLPPP inhibited ACE more effectively as verified with binding energies of -11.3, -11.6, -10.5, and -11.6 kcal mol-1, respectively, as compared to captopril (-6.38 kcal mol-1). Compared with the binding energy of sitagliptin (-8.6 kcal mol-1), WNGPPGVF (-9.6 kcal mol-1), WPLPPFG (-9.8 kcal mol-1), LPPYLPS (-9.7 kcal mol-1), TPPFHLPPP (-10.1 kcal mol-1), and DPANLPWG peptides (-10.1 kcal mol-1) had greater inhibition potential against DPP IV. The peptides impeded ACE and DPP IV majorly via hydrophobic and hydrogen linkage interactions. The key amino acids TYR523, GLU384, and HIS353 were bound to the catalytic sites of ACE and GLN553, GLU206, PHE364, VAL303, and THR304 were bound to the DPP IV enzyme. The PHs can be used as ingredients in the feed or food industries with possible health advantages.

Exploration of corn distillers solubles from selective milling technology as a novel source of plant-based ACE inhibitory protein hydrolysates.

Plant-based protein concentrate (PC) was extracted from under-utilized corn distillers solubles comprising a distinctive heat-treated blend of corn and yeast proteins. Enzymolysis of PC with alcalase generated protein hydrolysate (PH) containing angiotensin converting enzyme (ACE) inhibitory peptides. A novel kinetic model is developed to elucidate enzymolysis kinetics of PC. The PH of greatest DH (∼25%) revealed maximum ACE inhibition (%). Fractionated PH (<3 kDa) had non-toxic and non-allergenic unique peptides encrypted with anti-ACE fragments. Promising bioactive peptides (PeptideRanker > 0.85) docked with ACE had free energies between -8.40 and -10.60 kcal.mol-1 greater than captopril (-6.34 kcal.mol-1). The yeast-derived RLLPF peptide interacted with all active pockets of ACE (S1, S2, S') via hydrogen-, polar- and hydrophobic-bonds. Docking results suggested that ARG522, VAL518, TRP357, TYR523, GLU384, ALA356, ARG124, HIS387, HIS410, ASN66, and ALA354 of ACE aided in stabilizing complexes with peptides. Thus, PH could be used as antihypertensive ingredient for feed, food, or pharmaceutical industries.

Machine learning techniques for analysis of hyperspectral images to determine quality of food products: A review.

Non-destructive testing techniques have gained importance in monitoring food quality over the years. Hyperspectral imaging is one of the important non-destructive quality testing techniques which provides both spatial and spectral information. Advancement in machine learning techniques for rapid analysis with higher classification accuracy have improved the potential of using this technique for food applications. This paper provides an overview of the application of different machine learning techniques in analysis of hyperspectral images for determination of food quality. It covers the principle underlying hyperspectral imaging, the advantages, and the limitations of each machine learning technique. The machine learning techniques exhibited rapid analysis of hyperspectral images of food products with high accuracy thereby enabling robust classification or regression models. The selection of effective wavelengths from the hyperspectral data is of paramount importance since it greatly reduces the computational load and time which enhances the scope for real time applications. Due to the feature learning nature of deep learning, it is one of the most promising and powerful techniques for real time applications. However, the field of deep learning is relatively new and need further research for its full utilization. Similarly, lifelong machine learning paves the way for real time HSI applications but needs further research to incorporate the seasonal variations in food quality. Further, the research gaps in machine learning techniques for hyperspectral image analysis, and the prospects are discussed.

Glycemic index of pulses and pulse-based products: a review.

Pulses are a major source for plant-based proteins, with over 173 countries producing and exporting over 50 million tons annually. Pulses provide many of the essential nutrients and vitamins for a balanced and healthy diet, hence are health beneficial. Pulses have been known to lower glycemic index (GI), as they elicit lower post prandial glycemic responses, and can prevent insulin resistance, Type 2 diabetes and associated complications. This study reviews the GI values (determined by in vivo methodology) reported in 48 articles during the year 1992-2018 for various pulse type preparations consumed by humans. The GI ranges (glucose and bread as a reference respectively) for each pulse type were: broad bean (40 ± 5 to 94 ± 4, 75 to 93), chickpea (5 ± 1 to 45 ± 1, 14 ± 3 to 96 ± 21), common bean (9 ± 1 to 75 ± 8, 18 ± 2 to 99 ± 11), cowpea (6 ± 1 to 56 ± 0.2, 38 ± 19 to 66 ± 7), lentil (10 ± 3 to 66 ± 6, 37 to 87 ± 6), mung bean (11 ± 2 to 90 ± 9, 28 ± 1 to 44 ± 6), peas (9 ± 2 to 57 ± 2, 45 ± 8 to 93 ± 9), pigeon peas (7 ± 1 to 54 ± 1, 31 ± 4), and mixed pulses (35 ± 5 to 66 ± 23, 69 ± 42 to 98 ± 29). It was found that the method of preparation, processing and heat applications tended to affect the GI of pulses. In addition, removal of the hull, blending, grinding, milling and pureeing, reduced particle size, contributed to an increased surface area and exposure of starch granules to the amylolytic enzymes. This was subsequently associated with rapid digestion and absorption of pulse carbohydrates, resulting in a higher GI. High or increased heat applications to pulses were associated with extensive starch gelatinization, also leading to a higher GI. The type of reference food used (glucose or white bread) and the other nutrients present in the meal also affected the GI.

Ultrasound-assisted alkali-urea pre-treatment of Miscanthus × giganteus for enhanced extraction of cellulose fiber.

Ultrasound-assisted-alkali-urea (UAAU) pre-treatment of miscanthus biomass was investigated for enhanced delignification and extraction of cellulose fiber. The effects of pre-treatment conditions investigated were: sonication time (10.0, 15.0 and 20.0 min), alkali (NaOH) concentration (2.0, 3.5 and 5.0 %, w/v) and urea-concentration (1.0, 1.75 and 2.5 %, w/v) on the delignification and cellulose content. The process parameters were studied and optimized using a response surface methodology (RSM) based on the Box Behnken Design (BBD). From the RSM-BBD analysis, he optimized pre-treatment conditions were 2.1 % NaOH, 1.7 % urea and 15.5-min sonication time with maximal cellulose and lignin contents of 47.8 % (w/w) and 27.5 % (w/w) respectively. The pre-treated samples were further characterized by FTIR, colorimeter, SEM, XRD, and TGA analyses. The UAAU pre-treated samples have higher delignification and cellulose contents than the AU pre-treatment without sonication. Furthermore, the ultrasound process allowed selective removal of lignin without substantially degrading the functionalities of cellulose fiber. The UAAU pre-treated samples exhibited higher thermal stability, fibrillation, crystallinity index and smaller crystallite size.

Processing methods for reducing alpha-galactosides in pulses.

Pulses are an excellent source of protein and dietary fiber and are consumed around the world. Their consumption has been recommended as part of a healthy diet. However, they contain various antinutrients such as tannins and trypsin inhibitors, as well as indigestible carbohydrates called alpha-galactosides. These oligosaccharides are fermented by the microorganisms in the gut, producing gas and causing flatulence in healthy individuals. While this flatulence is undesirable (and results in their low acceptance in the Western diet), alpha-galactosides have also been hypothesized to increase susceptibility to bowel diseases, and their presence in the gut worsens the symptoms of patients with irritable bowel syndrome. The elimination of alpha-galactosides by breeding is difficult as they play a vital role in maintaining seed viability through periods of drought and cold. There is a critical need to evaluate the various post-harvest processing methods, and their effect on alpha-galactoside removal to facilitate commercialization. This paper reviews the effectiveness of methods and processing conditions in alpha-galactoside removal from a variety of pulses.

Rheological properties of rice-blackgram batter while replacing white rice with brown rice.

Rice-blackgram batter is a raw material for many traditional convenience foods in Asia. Reformulation of traditional convenience food by replacing white rice with whole rice (brown rice) is a novel method to reduce the consumption of refined grain and increase the intake of whole grain in our diet. In this study, rheological properties of rice-blackgram batter was investigated while replacing white rice with brown rice at five levels (T1--0% replacement (control), T2--25% replacement, T3--50% replacement, T4--75% replacement, and T5--100% replacement). The shear stress versus shear rate plot indicates that the rice-blackgram batter exhibited non-Newtonian fluid behavior (shear thinning property) even after 100% replacement of white rice with brown rice. The rheological characteristics of rice-blackgram batters fitted reasonably well in Cassan (r2 = 0.8521-0.9856) and power law (r2 = 0.8042-0.9823) models. Brown rice replacement at all levels did not affect the flow behavior index, yield stress, consistency coefficient, and apparent viscosity of batter at 25 degrees C. However, at higher temperature, the viscosity was greater for T4 and T5 (no difference between them) than T1, T2, and T3 (no difference between them) batters. Further research is required to determine the sensory attributes and acceptability of the cooked products with brown rice-blended batter.