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The effect of screw speed and oyster mushroom addition on the texture characteristics (hardness, gumminess, and chewiness) and specific mechanical energy (SME) was determined via factorial experiment design. Individually increasing screw speeds had little effect compared to the effects of oyster mushroom addition. However, the combined effects of screw speed and oyster mushroom addition significantly reduced (p ≤ 0.05) all the texture characteristics. The hardness (3521.35 g) and gumminess (2717.85) of the meat analog extruded at the maximum screw speed of 160 rpm and 15% oyster mushroom addition are close to the chicken breast’s characteristics, respectively. The oyster mushroom–soy protein extrudates are chewier than the non-hydrated texturized vegetable protein (TVP) and chicken meats. The SME values of the single-screw extrusion were linearly affected by the increasing screw speed, which also lies in the range < 200 kJ/kg for producing meat analog with acceptable characteristics. Applying the superposition technique successfully shifted the individual curves of the SME into a smooth master curve vertically, allowing an interpolating in the prediction of SME value at a given screw speed value.

Recently, frequent discharge of water-ladened emerging organic pollutants such as Bisphenol A has generated serious concern owing to its harmful effects on public safety and the ecological environment. Hematite nanoparticles (Fe2O3) were synthesized via the sol-gel auto-combustion procedure and utilized as a nanofiller to fabricate a PVDF-PEG/Fe2O3 nanocomposite hollow fibre membrane with enhanced antifouling properties. A series of membranes comprising various loadings (1.0–2.0 wt.%) of Fe2O3 NPs were fabricated through the phase inversion technique and thoroughly analyzed. The developed Fe2O3-membrane fibres were thoroughly characterized. The performance of the membrane fibres was investigated through permeation flux, BPA rejection, as well as antifouling characteristics. Based on the results obtained, the resultant nanocomposite membrane fibres exhibited superior performance in comparison with the pristine fibre. Also, the nanocomposite membrane with 1.5 wt.%-Fe2O3 NPs exhibited remarkable performance with − 43.7 mV, 56.3º, 191.85 L/m2-h, 86.7%, and 12% of negatively charged zeta potential, least contact angle, water permeation flux, BPA rejection, and minimum weight loss, respectively. Besides, the 1.5 wt-Fe2O3 NPs nanocomposite membrane demonstrated superior antifouling performance after the third filtration, accomplishing a higher percent of FRR (77.35%) along with RFR of 21.29%, respectively. Hence, based on the performance of the fabricated hollow-fibre membranes loaded with Fe2O3 NPs, efficient antifouling membranes was achieved which can be suitably applied in the purification of industrial wastewater.

Kelulut honey (KH) is a honey produced by stingless bee species, known for its high nutritional content and health benefits. Even though it is very healthy, some people cannot consume it directly. Therefore, incorporating this type of honey into an emulsion system is a good strategy to increase its consumption. Emulsion technology is one of the alternative technologies nowadays which combines two or more immiscible liquids to form a solution. In this study, KHemulsions were emulsified with glyceryl monostearate (GMS) and stabilised by xanthan gum. There were two stages involvedto determine the effects of variations in oil types and emulsifier concentrations on the physical properties of KH emulsions. In the first stage, three types of oil were used as the dispersed phase, which were palm oil, canola oil, and sunflower oil. Then in the second stage, different concentrations of GMS (0.25, 0.5, 0.75 and 1%) were applied. From the droplet size analysis, the emulsion with sunflower oil and the highest concentration of GMS gave the smallest diameter of 0.78 ± 0.01µm and the lowest polydispersity index (pdI) of 16.2±2.03 %. Meanwhile, the texture analysis shows that emulsion with palm oil has the highest firmness (45.16±2.83 g) and consistency (305.44±14.91 g.sec) values. The foaming index on the other hand depicts that emulsion with palm oil and that with the lowest concentration of GMS gave the highest foam stability. From this study, a physically stable oil-in-water KH emulsion was produced, which should undergo further chemical, sensory and storage studies for commercial production in the future.

The sweet potato (Ipomoea batatas) is an annual herb of the family Convolvulaceae and ranked as the world's seventh most important food crop with a major contribution to energy and phytochemical source of nutrition. Three different conditions of sweet potatoes are unpeeled tuber (UPSP), peeled tuber (PSP) and skin of tuber (SSP). The objective of this study is to evaluate the phytochemical availability (total phenolic contents (TPC), total flavonoid contents (TFC) and anthocyanin content) in the different parts of the sweet potato tuber. Folin-Ciocalteau (FC) assay showed that phenolic contents for UPSP (41.14±1.69 mg GAE/100 g dry basis) and PSP (42.24±2.19 mg GAE/100 g dry basis) were significantly (50%) higher than SSP (26.01±2.04 mg GAE/100 g dry basis). In terms of flavonoid content, the highest value was retained in PSP (9.55±0.82 mg quercetin/100 g dry basis) followed by UPSP (3.30±0.19 mg quercetin/100 g dry basis) and SSP (1.43 ± 0.03 mg quercetin/100 g dry basis). PSP (9.43±0.08 mg/100 dry basis) had a higher anthocyanin content compared to UPSP (5.21±0.02 b mg/100 g dry basis) and SSP (5.21±0.02 b mg/100 g dry basis). The phytochemical properties were available in all conditions of the sweet potato. However, PSP was suggested to be the most preferable condition for further processing in the sweet potato industry.

Cassava (Manihot esculenta Crantz) is one of the main sources of carbohydrate and it is a useful plant in Malaysia. Its root is used to produce various foods such as cassava chips, while the other parts are potentially to produce feeds and other useful products. However, details observation in the proximate composition of each part of the cassava plant is important in utilizing it as an animal feed, especially for the ruminants. Hence, this research was conducted to evaluate the proximate composition of each part in the cassava plant and characterized its functional groups using Fourier-transform infrared spectroscopy (FTIR) and the thermal properties using thermogravimetric analyzer (TGA). The results obtained showed that the portions of fresh cassava plants namely flesh, stem, peel, discarded tuber and the leaf were recorded at 50.06%, 31.01%, 10.63%, 6.92% and 1.49% (w/w), respectively. Proximate analysis showed that the leaf has potential as animal feed as it contains significant high in crude protein (28.02±0.10%), crude fat (5.63± 0.12%) and the gross energy value of 4824.3 g/cal. Even though the leaf has a higher cyanide content (0.02 mg/kg) than other parts, it is still in acceptable range as an ingredient in animal feed. For animal feed that focuses on high protein and gross energy, the leaf has potential in feed ingredients. Meanwhile, cassava flesh also has potential as an animal feed since it has low crude fiber (2.11±0.03%) but high in carbohydrate (92.66±1.88%) and gross energy content (4223.9 cal/g). FTIR spectra showed that there were different functional groups present in the samples. From the TGA data, it showed that the major components in samples were cellulose which started to decompose rapidly at maximum degradation rate temperature of 315-400°C, especially for flesh and discarded tuber. Different parts of cassava plants are expected to help the agriculture industry in producing alternative animal feed at the same time minimizing the impact of waste generated in the environment.

Potato and sweet potato are two among the most important commodities worldwide due to their significant role in human diet and food security. As highly demanded crops, rapid quality monitoring methods prior to marketing, processing, and other post-harvest activities are the major concerns of consumers and food processors. The non-destructive techniques in terms of imaging and spectroscopy have become effective analytical tools in evaluating the quality of various horticultural and food products including potatoes and sweet potatoes. Hence, this paper reports the current knowledge on the recent applications of imaging and spectroscopy for inspecting the quality and safety of raw potato and sweet potato tubers. In this comprehensive review, the conventional quality evaluation (internal and external) are discussed, followed by description of imaging and spectroscopy as non-destructive techniques and, the summary of the recent successful implementations of these tools in relation to quality evaluation. The basic and fundamental components of the technique, measurement methods and data analysis applied, advantages, and challenges are also critically reviewed.

A corn-mango peel blend was processed using a laboratory-scale single-screw extruder, which led to the determination of the apparent density, yellowness, and specific mechanical energy of the extrudate. The effects of the extrusion variables (barrel temperature from 75–175°C, screw speed from 76–100 rpm, feed moisture from 15–21%, and mango peel powder addition from 0–33.33%) were analyzed, and predictive models were obtained using the response surface methodology (RSM). At elevated barrel temperature and screw speed, the extrudates’ apparent density decreased but then increased when the feed moisture and mango peel powder addition increased. At increasing barrel temperature but decreasing mango peel powder addition, the yellowness intensity decreased, and the same response was observed at a low barrel temperature and high mango peel powder addition. The calculated specific mechanical energy (SME) for the production of corn-mango peel extrudate was decreased as the barrel temperature increased.

Recently Bisphenol A (BPA) is one of the persistent trace hazardous estrogenic contaminants in the environment, that can trigger a severe threat to humans and environment even at minuscule concentrations. Thus, this work focused on the synthesis of neat and magnetic biochar (BC) as a sustainable and inexpensive adsorbent to remove BPA from aqueous environment. Novel magnetic biochar was efficiently synthesized by utilizing palm kernel shell, using ferric chloride and ferrous chloride as magnetic medium via chemical co-precipitation technique. In this experimental study, the influence of operating factors comprising contact time (20–240 min), pH (3.0–12.0), adsorbent dose (0.2–0.8 g), and starting concentrations of BPA (8.0–150 ppm) were studied in removing BPA during batch adsorption system using neat biochar and magnetic biochar. It was observed that the magnetically loaded BC demonstrates superior maximum removal efficiency of BPA with 94.2%, over the neat biochar. The functional groups (FTIR), Zeta potential, vibrating sample magnetometer (VSM), surface and textural properties (BET), surface morphology, and mineral constituents (FESEM/EDX), and chemical composition (XRD) of the adsorbents were examined. The experimental results demonstrated that the sorption isotherm and kinetics were suitably described by pseudo-second-order model and Freundlich model, respectively. By studying the adsorption mechanism, it was concluded that π-π electron acceptor–donor interaction (EAD), hydrophobic interaction, and hydrogen bond were the principal drives for the adsorption of BPA onto the neat BC and magnetic BC.

The production of Sago starch involving multiple processes and the grating process was the most important since the recovery of sago starch was directly affected. In order to produce a finer size of grated sago and high starch recovery, a new design of sago disc grating machine has been developed. A evaluation was performed to determine the optimum operation on the basis of the feeding rate and grating speed input on the sago disc grating machine, and the starch recovery as the output. The grated sago was dried and sieved at different sizes to analysis the size. A model equation was developed to predict the starch recovery. As the result, the optimum feeding rate was 0.1 m/min with 1500 rpm of grating speed produce 23.57% of sago starch recovery. Studies show that the feeding rate and grating speed affects the size of the grated sago produced (P

Durian known as the King of Fruit is a prominent, common native Southeast Asian fruit and very popular among the local Malaysians. Nowadays, there are various types of durian-based products available in the market such as ice-cream, cakes, chips, chocolate bars, and pre-mixed powders. There are also traditional dessert products produced using fresh durian filling such as ‘dodol’, ‘lempuk’ and ‘bingka’. However, as time goes on, traditional desserts are increasingly forgotten. The aim of this study was to diversify durian-based products into Ready-To-Eat (RTE) durian stick. The stick production technique began with the process of grinding the durian paste, mixing the ingredients, stuffing the mixture into the sausage casing, steaming the mixture and chilling the RTE durian stick. Next, the firmness and moisture content of the RTE durian stick production were also analyzed. Apart from that, sensory evaluation is conducted to determine the consumer acceptance of the RTE durian stick that has been produced. Based on the results obtained, the best firmness for this RTE durian stick is 10.42 N. The value of the moisture content obtained is high, which is between 52.05% to 61.89%. The overall acceptability of RTE durian stick resulted 3.7 out of its full score which is 5. For the RTE durian stick, where the RTE durian stick was satisfactory to the panellists, the overall acceptability showed a score of 74%. In conclusion, this method can be used to increase the added value and uniqueness of the RTE durian-based stick produced, however, improvements such as product formulations and freezing methods to extend the product’s shelf life is necessary for the future to produce better RTE dessert products. The RTE durian stick has potential to be commercialized for local and international markets based on the overall acceptability in terms of the texture, appearance, smell and taste.

Starch is one of the food sources that can be extracted from cereals, roots, tubers and stem. Sago palm (metroxylon spp.) is one example of the starch source. The efficiency of the starch extraction process depends on the mechanical properties of process material. This study was conducted to determine the angle of repose between grated sago and kinetic friction of the contact surface between process material and machine. The angle of repose (θ) of grated sago was determined by using a cone shape hopper attached to an adjustable height bar. The cone was filled with a 100g sample of grated sago and slowly adjusted to an upward direction to release the grated sago and will form a conical shape. The cone shape base diameter and height were measured. Next, a square block of debarked sago trunk (8cm × 8cm × 8cm) was placed on a stainless steel plate and attached to a rope at middle connected to force gauges. The pulling speed was at 1.27 mm/min and the result of total pulling load (F) was recorded. The process was repeated for materials with different moisture content (MC) of 60%, 50%, 40%, and 30%. Based on the experimental results, the angle of repose (AoR= 47.000±0.31) and coefficient of kinetic friction (μ k) 0.88±0.005 at MC= 60% showed decrease in value (AoR= 43.610±0.34; μ k = 0.83±0.002) when the MC decrease by 30% (P

Sweet potato (Ipomoea batatas) is among the most popular crop around the world. Physicochemical properties are an important element in the sweet potato processing industry. However, little knowledge is known about this variety of sweet potatoes. In this study, colour, moisture, ash, protein, fat, crude fibre and carbohydrate were studied subjected to three different conditions of Japanese sweet potato; whole tuber (C1), peeled tuber (C2) and skin of tuber (C3). Colour and proximate analysis were determined using the lightness (L), red/green (a) and yellow/blue (b) system and AOAC method, respectively. The result indicated that L, a* and b* ranged from 68.0–89.2, 0.48–5.65 and 11.67–13.27, respectively. The highest values of L, a and b were observed in C1, C3 and C1, respectively. Moisture, ash, protein, fat, carbohydrate and fibre were ranged from 5.93–7.86%, 2.64–8.11%, 4.64–5.47%, 0.06–0.70%, 65.96–86.96% and 1.00–2.43%, respectively. C1 had the highest value of moisture content while C2 showed to have the highest values of protein and carbohydrate. C3 was observed to have the significantly highest (p < 0.05) content of ash, lipid and crude fibre. Overall, the differences in the physicochemical properties of three different conditions of sweet potato are significant in certain properties. C1 was suggested to be the best selection for producing better quality sweet potato products. Therefore, the result obtained from this study becomes useful for further processing of sweet potatoes.

Cassava (Manihot esculenta Crantz) is the third-largest carbohydrate food source in the tropical region after rice and corn. Its flesh is used to produce foods, while the other parts of the plant are not fully exploited. This research aimed to evaluatetheproximate composition of the cassava plant (Rayong 90 variety). Six different parts namely leaf, petiole, young stem, tuber, cortex and periderm of white variety cassava plants were dried and powdered to determine their proximate composition (protein, carbohydrate, fat, crude fiber, ash, moisture). The results show that the leaf is the most nutritional compared to other parts. Leaf had 43.80% carbohydrate, 23.87% protein, 13.66% crude fiber, 6.53% ash, 6.00 % crude fat and 5.00% moisture content. The crude protein for other parts were very low, ranging from 2.54% to 10.20%. The white cassava variety plant was very high in carbohydrates, ranging from 30.48% to 86.77% of dry matter. The mean percentage of crude fat found within the range from 0% to 6.00%. From the results, it can be concluded that a leaf of white cassava variety can be used to develop a potential high carbohydrate and protein ruminant feed because it has appreciable levels of the nutrient.

Banana puree is one of the main commercial banana products available in the market worldwide. However, like other purees, banana puree deteriorates quite rapidly and gets a chilling injury when refrigerated. Therefore, this study focused on the dehydration of banana puree using a foam mat drying (FMD) technique to prolong its shelf life. It involved whipping the banana puree to form foams with the help of whey protein concentrate (WPC) and carboxymethyl cellulose (CMC) as the foaming agent and foam stabilizer, respectively. The study evaluated the effect of different foaming agent percentages (5, 7.5, 10, 12.5 and 15%) and drying temperatures (50, 60, 70 and 80°C) on the production of the foam mat dried banana powder. Besides that, the drying curves of banana puree using FMD and oven drying methods were compared. The banana powders produced were also analyzed in terms of the foam density, moisture content, solubility, color (browning index) and flowability (caking strength). Based on the findings, the FMD technique has proven to produce a good quality banana powder better than the control sample especially at a higher foaming agent concentration (15%) and drying temperature (80°C). By using the FMD technique, the banana puree has the capacity to be dried three times faster compared to the conventional oven drying method to form a more stable banana powder.

Paperboard box produced in large volume for packaging purpose either to pack light or heavy product. When a heavy product is packed, high strength and structural stability against compression and deformation of the paperboard box are demanded. This paper investigates the effects of different shape of fluting mediums on the von Mises stress and deformation using finite element analysis (FEA) tool. Solidworks and ANSYS software were used to design a 3-D model and perform static structural analysis, respectively. The result from the analysis and simulation revealed that common s-shape geometry experienced the lowest von Mises stress and deformation. Honeycomb geometry experienced the highest von Mises stress of 0.19576 MPa while triangle fluting medium recorded the highest deformation at 1.8695E-4mm.

Non-destructive quality evaluation of agricultural products particularly during postharvest stage has been a primary concern in recent years. The laser-based imaging technology is one of the most promising non-invasive tools which demonstrate potential ability to replace the conventional methods of quality monitoring that are time-consuming, expensive, laborious, inaccurate and most of all destructive. Hence, in this paper, we briefly reviewed the potential application of laser-light backscattering imaging technique (LLBI) as a non-destructive quality evaluation tool applied in agricultural products. This review mainly reports the current knowledge on the successful implementations of the LLBI in measuring the various quality-related attributes of agricultural products under different postharvest conditions such as in drying, storage, sorting, maturity identification, defect detection, etc. The basic components, uses and considerations of the technique are highlighted in this paper. Moreover, the advantages, drawbacks, measurement methods, data analysis applied as well as the accuracies obtained are briefly summarized.

Orange-fleshed sweet potato (OFSP) offers many health benefits and can be processed into different food forms including as a healthy drinking juice. However, the OFSP juice requires exploration on the juice properties, especially its nutritional elements before it can be marketed as a healthy drink. Hence, this study aimed to address the detailed nutritional composition of the OFSP juice via analyses of proximate compositions, amino acids, mineral, carotenoids, and vitamins. Findings showed OFSP juice is proven to be high in beta-carotene with a value of 4916.06 μg/L which was almost 100 times the value of beta-carotene in orange juice, and also rich in vitamins, certain amino acids and minerals. Since these phytochemicals can aid in the reduction of anti-mutagenic, immune-enhancers, cancer, and free radical scavengers, this study has proven the potential of OFSP to be processed into a healthy juice based on its nutritional properties.

The drying characteristics of ‘Berangan’ banana flesh dried under microwave heating were studied in this work.The produced microwave banana chip was then compared with the conventional deep oil fried banana chip in terms of colour and sensory characteristics.‘Berangan’ banana slices with 3 mm thickness were dried using microwave at three power levels of 100,440 and 1000 W. Shorter drying times were obtained when higher microwave power was applied during drying, where the drying times were found to be 30, 7, 4 min at 100, 440 and 100W. Three different drying models were used to describe the resulting drying curves. The drying rate constant increased from 0.298, 0.4211 and 0.2977 min-1 to 1.8717, 1.9956 and 1.8936 min-1 for the Newton, Page and Henderson and Pabis models when the microwave power used was increased from 100W to 1000W. The best model to represent the drying data obtained in this work was found to be the Page model. In terms of colour, fried banana had a browner, duller colour than microwave dried banana. For sensory evaluation, dried banana chips using microwave at a power level of 440W was the most preferable. It can be concluded microwave dried banana chips showed better results than fried banana chips in terms of colour and sensory characteristics in the range tested in this study.

In recent years, downstream bioprocessing industries are venturing into less tedious, simple, and high-efficiency separation by implementing advanced purification and extraction methods. This review discusses the separation of proteins, with the main focus on amylase as an enzyme from agricultural waste using conventional and advanced techniques of extraction and purification via a liquid biphasic system (LBS). In comparison to other methods, such as membrane extraction, precipitation, ultrasonication, and chromatography, the LBS stands out as an efficient, cost-effective, and adaptable developing method for protein recovery. The two-phase separation method can be water-soluble polymers, or polymer and salt, or alcohol and salt, which is a simpler and lower-cost method that can be used at a larger purification scale. The comparison of different approaches in LBS for amylase purification from agricultural waste is also included. Current technology has evolved from a simple LBS into microwave-assisted LBS, liquid biphasic flotation (LBF), thermoseparation (TMP), three-phase partitioning (TPP), ultrasound-assisted LBS, and electrically assisted LBS. pH, time, temperature, and concentration are some of the significant research parameters considered in the review of advanced techniques.

According to the Food Wastage Footprint and Climate Change Report, about 15% of all fruits and 25% of all vegetables are wasted at the base of the food production chain. The significant losses and wastes in the fresh and processing industries is becoming a serious environmental issue, mainly due to the microbial degradation impacts. There has been a recent surge in research and innovation related to food, packaging, and pharmaceutical applications to address these problems. The underutilized wastes (seed, skin, rind, and pomace) potentially present good sources of valuable bioactive compounds, including functional nutrients, amylopectin, phytochemicals, vitamins, enzymes, dietary fibers, and oils. Fruit and vegetable wastes (FVW) are rich in nutrients and extra nutritional compounds that contribute to the development of animal feed, bioactive ingredients, and ethanol production. In the development of active packaging films, pectin and other biopolymers are commonly used. In addition, the most recent research studies dealing with FVW have enhanced the physical, mechanical, antioxidant, and antimicrobial properties of packaging and biocomposite systems. Innovative technologies that can be used for sensitive bioactive compound extraction and fortification will be crucial in valorizing FVW completely; thus, this article aims to report the progress made in terms of the valorization of FVW and to emphasize the applications of FVW in active packaging and biocomposites, their by-products, and the innovative technologies (both thermal and non-thermal) that can be used for bioactive compounds extraction.

The shelf life of banana is very much dependent on the preparation method, packaging method, and storage temperature. Thus, this work is directed to investigate the effect of banana preparation (peeled and unpeeled), packaging method (vacuum packed and non-vacuum packed), and storage temperature (25 and 9 °C) on extending the shelf life of Saba banana. Peeled and unpeeled; and vacuum packed and non-vacuum packed banana was kept at different storage temperatures for 28 days. The shelf life of banana was investigated in terms of texture, color changes, and moisture content every 7 days. It was found that vacuum packed banana samples kept at 9 °C exhibited non-significant changes in firmness, and minimal changes in moisture content and color compared to non-vacuum packed banana kept at 25 °C, proving that vacuum packaging and low storage temperature are promising to extend the shelf life of banana. The unpeeled banana was also demonstrated to exhibit longer shelf life compared to peeled banana because the skin is able to preserve the moisture content inside the banana and prevent the banana to become dried and spoilt over time.

In this study, we investigated the effects of different storage temperatures on the quality and shelf-life of Malaysian sweet potatoes in terms of moisture content (MC), soluble solids content (SSC), colour values (L*, a*, b*) and textural properties. Samples from the three locally-produced sweet potato varieties in Malaysia namely: Keledek Anggun 3 (V1), Keledek Jingga (V2), and Keledek Kuning (V3) were purchased and stored at 5 °C, 15 °C and 30 °C for a period of 21 d with a relative humidity (RH) range of 80–90%, 70–80% and 50–60%, respectively. A multiple correlation analysis was employed in establishing the relationships between the changes in all the quality parameters (QP). The results showed that the QP of sweet potatoes in all varieties were significantly affected (P 0.60; *P

Water is a critical resource necessary for life to be sustained, and its availability should be secured, appropriated, and easily obtainable. The continual detection of endocrine-disrupting chemicals (EDCs) (ng/L or µg/L) in water and wastewater has attracted critical concerns among the regulatory authorities and general public, due to its associated public health, ecological risks, and a threat to global water quality. Presently, there is a lack of stringent discharge standards regulating the emerging multiclass contaminants to obviate its possible undesirable impacts. The conventional treatment processes have reportedly ineffectual in eliminating the persistent EDCs pollutants, necessitating the researchers to develop alternative treatment methods. Occurrences of the EDCs and the attributed effects on humans and the environment are adequately reviewed. It indicated that comprehensive information on the recent advances in the rejection of EDCs via a novel membrane and membrane bioreactor (MBR) treatment techniques are still lacking. This paper critically studies and reports on recent advances in the membrane and MBR treatment methods for removing EDCs, fouling challenges, and its mitigation strategies. The removal mechanisms and the operating factors influencing the EDCs remediation were also examined. Membranes and MBR approaches have proven successful and viable to eliminate various EDCs contaminants.

Optical imaging techniques have gained wide attention for quality detection of agricultural and food products. In this work, the non-destructive ability of the laser-light backscattering imaging technique (LLBI) for monitoring and classifying the quality changes of sweet potatoes under different storage conditions was investigated. Freshly-harvested sweet potato root samples were stored at 5 °C, 15 °C and 30 °C for a period of 21 d with 120 samples in each storage group. Laser diode emitting light at 658 nm wavelength along with the camera system was employed to capture the backscattered light from the subjected samples. The acquired backscattering images were then pre-processed and segmented, and the intended backscattering parameters (BP) were extracted. Quality parameters (QP) such as moisture content (MC), soluble solids content (SSC), texture and color properties (L*, a*, b*) were measured using the conventional methods as standard reference data. Multivariate analysis in terms of partial least squares regression (PLSR), principal component analysis (PCA) and linear discriminant analysis (LDA) was carried out to correlate and classify the sweet potatoes based on the BP. Results showed that storage had a significant effect both in the BP and QP of sweet potatoes as well as in the interaction between the BP and the treatments (day and temperature) applied. Among all the QP, SSC gave the most promising results (R = 0.56-0.66; RMSE = 0.76–1.10) across all the storage conditions. The analysis also revealed that 15 °C was the most suitable storage condition with the favourable PLSR results (R > 0.50) in all the examined parameters. Moreover, variations on the BP of the samples with respect to the different storage conditions were correctly classified with over 90 % and 80 % accuracies using the PCA and LDA, respectively. Thus, the study indicates that the LLBI technique is feasible and can be a useful tool for a non-destructive quality measurement and classification of sweet potatoes under different storage conditions.

Non-destructive quality monitoring for horticultural products by means of optical imaging methods have gained wide interest in recent years. This study sought to investigate the potential use of laser-light backscattering imaging technique (LLBI) for non-invasive quality evaluation of sweet potatoes of different varieties after being harvested and stored at ambient temperature. A total of 360 newly harvested samples from the three varieties of locally-produced sweet potatoes in Malaysia i.e. Keledek Anggun 3, Keledek Jingga, and Keledek Kuning were purchased and stored in an ambient room temperature (28–30 °C) for a period of twenty one (21) days. After each 7-day storage, respective samples were taken out and backscattering images (BSI) were acquired using a charge-coupled device (CCD) camera attached with laser diodes emitting lights at 658 nm and 780 nm wavelengths, respectively. Quality attributes such as moisture content (MC), soluble solid content (SSC), textural properties (hardness, fracturability, adhesiveness), and flesh color properties (L*, a*, b*) as reference quality parameters (QP) were measured right after BSI acquisitions. Multiple Linear Regression (MLR) was applied to correlate and predict the relationship between the extracted backscattering parameters (BP) and the QP. Results revealed that there were significant changes (P 0.70) with BP, particularly the Keledek Kuning variety. The 658 nm wavelength showed better prediction results than 780 nm with r > 0.85 in measuring the textural properties. Thus, the study demonstrated the feasibility of LLBI as a useful non-destructive technique to evaluate the quality of sweet potatoes and can be further utilized for online optical quality grading.

Membrane technology has been successfully applied for the purification of bromelain, a protease enzyme from pineapple. However, the current system operates less optimally in terms of flux and separation primarily due to properties of the feed, such as viscosity. Hence, in this study, enzymatic pretreatment and diafiltration operation were employed in a two-stage ultrafiltration (UF) system to enhance the performance of the purification and concentration process of bromelain enzyme from an extract of pineapple crude waste mixture (CWM). Pretreatment of the CWM extract using either pectinase or cellulase, or the combination of both, was applied and compared regarding the apparent viscosity reduction. Diafiltration step was introduced in UF stage 2 and observations on the flux performance, enzyme recovery and enzyme purity were made. A 12 % apparent viscosity reduction was achieved when the CWM extract was pretreated with pectinase which led to 37-38 % improvement in the flux performance of both UF stages, as well as higher enzyme recovery in UF stage 1. The introduction of diafiltration mode in UF stage 2 managed to sustain high flux values while yielding 4.4-fold enzyme purity (higher than a 2.5-fold purity achieved in our previous work); however, high diluent consumption was needed. The outcomes of this study showed that the flux performance and bromelain separation can be enhanced by reducing the viscosity with the employment of enzymatic pretreatment and diafiltration operation. Thus, both techniques can be potentially applied in a large-scale membrane-based process for bromelain production.

This work describes the effect of a repetitive cooking-chilling process on resistant starch content in crackers prepared from a mixture of fish and starch, which are popularly known in Malaysia as “keropok.” Three fish cracker formulations were prepared using tapioca, wheat, and sago starch. Up to four cycles of repetitive cooking-chilling increased the resistant starch content in all products; however, the hardness of chilled samples decreased, and their moisture content increased. For the fried samples, the texture became harder, the color turned darker, and linear expansion was reduced. The dried fish cracker samples prepared with sago starch yielded the highest resistant starch content. The results demonstrated that four cycles of repetitive cooking-chilling were able to enhance resistant starch in fish crackers.

A dynamic mathematical model was used in this study to describe the mass transfer and reaction kinetics of a fouled α–CGTase–CNF layer in a biocatalytic membrane reactor (BMR) system. BMR performance was evaluated based on the effect of substrate concentration and pneumatic gauge pressure on the permeate flux, total permeate volume, starch conversion, and α-CD production. A model is introduced based on the layer of mass limit as the resistance blocking mechanism with reaction kinetics on the fouled α–CGTase–CNF layer. Important unknown parameters of the constants describing the layer resistance, KML0 and the kinetic constant of Michaelis-Menten, kcat, for mass transfer and its reaction kinetics, were successfully estimated at 3.9 × 107 min/mL and 216.18 mg-starch/cm3⋅U⋅min, respectively, using the proposed models. The study found that the kcat value corresponding to the maximum efficiency of the enzyme on starch cyclisation was a critical parameter in the prediction of the BMR dynamic profiles. Thus, the proposed model in this study can be used for further development of the BMR system, with excellent hydrodynamic and reaction performance.

The heat treatment of oil palm fruit using saturated steam (413 K) in conventional oil palm processing has been reported to be ineffective in terms of heat distribution and penetration into the fruit bunch inner layer, hence, there is a desire to explore other alternative processes. In this study, oil palm fruit was treated in water at temperatures between 308 K and 343 K. The effects of the treatment on the in vivo activity of the lipase, the abscission layer of the fruit, and the integrity of the oil globule membrane were observed. The results showed in vivo residual lipase activity to be almost completely inactivated after 40 min of heat treatment at 343 K. The micrograph of the fruit mesocarp exhibited disintegration of the oil globule membrane as well as dissolution of the pectin layer architecture of the abscission zone after the treatment at this temperature. A dynamic mathematical modeling of heat transfer was employed, and coupled with reaction kinetics of lipase inactivation. The inactivation kinetics was found to be a non-elementary reaction, and the initial rate constant, k0dec, and activation energy, Edec, of the reaction were estimated to be 0.035 U&minus, 0.85/kg-mes&minus, 0.85&sdot, min and 153,052 kJ/kmol, respectively. The findings suggested the viability of water as a medium of heat treatment instead of the conventional steam treatment in oil palm processing.

The two-stage ultrafiltration (UF) process was recently successfully applied to purify bromelain from pineapple crude waste mixture (CWM); however, further process improvements were required. Effects of manipulating transmembrane pressure (TMP) and cross-flow velocity (ʋ) on the flux profile, enzyme recovery and enzyme purity were investigated at TMP of 1.0, 1.5, or 2.0 bar and ʋ of 0.16, 0.24, or 0.30 m/s. High TMP and ʋ resulted in high flux in both UF stages. Performing the process at the highest TMP and ʋ of 2.0 bar and 0.30 m/s, respectively, yielded the highest enzyme recovery in UF stage 1 (76.9%), but the lowest purity fold in UF stage 2 (1.4-fold). The effects were inverted at reduced TMP and ʋ conditions. For appropriate flux and enzyme separation effectiveness, the process should be conducted at 2.0 bar and 0.30 m/s in UF stage 1, and 1.5 bar and 0.24 m/s in UF stage 2. Practical applications An efficient purification technique is needed for bromelain production in order to improve the quality of purified enzyme as well as to reduce the overall processing cost. Thus, a developed membrane-based process has been further improved for bromelain purification in effort to establish process feasibility, practicality and effectiveness. In-depth deliberation on the effect of selected processing conditions (TMP and ʋ) on membrane performance and bromelain separation in a two-stage UF process system has been presented in this work. It provides insight into the flux performance, fouling formation as well enzyme separation during the membrane process. Hence, the best processing conditions can be selected, which would bring to and even lower cost system suitable for large-scale bromelain production.