Puffing Process Research Articles

Dynamic changes in quality and flavor compounds of pork tendons during puffing process

To improve the portability of dried pork tendons for consumption, this study investigated the effects of different puffing temperatures (190 °C - 250 °C) and times (1-7 min) on the quality and flavor of pork tendons. As the temperature and time increased, the expansion ratio of pork tendons exhibited a gradual increase. The microstructure of the puffed pork tendons exhibited a uniform porous structure at 230 °C and 250 °C for 6 min. However, further puffing treatment destroyed the spatial structure. GC-IMS identified 68 volatile organic compounds (VOCs), and a total of 16 key VOCs including 2-trans-4-trans-decadienal were screened by GC-MS. Nonanal, 1-octen-3-ol, 2-amylfuran and 2-ethylfuran proved to have a significant effect on the flavor of the puffed pork tendon. The combined puffing performance and flavor analysis revealed that puffing at 230 °C for 6 min was the preferred parameter for puffed pork tendons.

CO2 Utilization and Sequestration in Organic and Inorganic Nanopores During Depressurization and Huff-n-Puff Process.

CO2 injection in shale reservoirs is more suitable than the conventional recovering methods due to its easier injectivity and higher sweep efficiency. In this work, Grand Canonical Monte Carlo (GCMC) simulation is employed to investigate the adsorption/desorption behavior of CH4-C4H10 and CH4-C4H10-CO2 mixtures in organic and inorganic nanopores during pressure drawdown and CO2 huff and puff processes. The huff and puff process involves injecting CO2 into the micro- and mesopores, where the system pressure is increased during the huffing process and decreased during the puffing process. The fundamental mechanism of shale gas recovery using the CO2 injection method is thereby revealed from the nanopore-scale perspective. During primary gas production, CH4 is more likely to be produced as the reservoir pressure drops. On the contrary, C4H10 tends to be trapped in these organic nanopores and is hard to extract, especially from micropores and inorganic pores. During the CO2 huffing period, the adsorbed CH4 and C4H10 are recovered efficiently from the inorganic mesopores. On the contrary, the adsorbed C4H10 is slightly extracted from the inorganic micropores during the CO2 puffing period. During the CO2 puff process, the adsorbed CH4 desorbs from the pore surface and is thus heavily recovered, while the adsorbed C4H10 cannot be readily produced. During CO2 huff and puff, the recovery efficiency of CH4 is higher in the organic pores than that in the inorganic pores. More importantly, the recovery efficiency of C4H10 reaches the highest levels in both the inorganic and organic pores during the CO2 huff and puff process, suggesting that the CO2 huff and puff method is more advanced for heavier hydrocarbon recovery compared to the pressure drawdown method. In addition to CO2 storage, CO2 sequestration in the adsorbed state is safer than that in the free state. In our work, it was found that the high content of organic matter, high pressure, and small pores are beneficial factors for CO2 sequestration transforming into adsorbed state storage.

Exploring puffed rice as a novel ink for 3D food printing: Rheological characterization and printability analysis

This study introduces a novel approach by using puffed rice (PR) as a sustainable and innovative ink for 3D food printing. Due to gelatinization and dextrinization, PR saw notable water absorption and solubility gains, with a modest viscosity uptick from 39.2 to 49.9 RVU, sharply contrasting Native rice (NR)'s jump from 128.9 to 167.8 RVU, emphasizing PR's minimal retrogradation. Gelatinized rice (GR) demonstrates similar stability in viscosity changes as PR, yet it requires more water and extended processing times for gelatinization. Conversely, PR's puffing process, which eliminates the need for water, offers quicker preparation and notable environmental benefits. Rheological analysis at 25% PR concentration reveals an optimal balance of viscosity (η, 897.4 Pa s), yield stress (τy, 2471.3 Pa), and flow stress (τf, 1509.2 Pa), demonstrating superior viscoelastic properties that facilitate enhanced printability and shape fidelity. Texture Profile Analysis outcomes reveals that PR significantly enhances key textural properties including hardness, adhesiveness, and springiness at this specific concentration. These findings highlight PR's potential as an eco-friendly and efficient ink choice for 3D-printed food products, providing enhanced performance and sustainability compared to GR and NR.

Enhancement of Benzene Emissions in Special Combinations of Electronic Nicotine Delivery System Liquid Mixtures.

Electronic nicotine delivery systems (ENDS) are battery-powered devices introduced to the market as safer alternatives to combustible cigarettes. Upon heating the electronic liquid (e-liquid), aerosols are released, including several toxicants, such as volatile organic compounds (VOCs). Benzene has been given great attention as a major component of the VOCs group as it increases cancer risk upon inhalation. In this study, several basic e-liquids were tested for benzene emissions. The Aerosol Lab Vaping Instrument was used to generate aerosols from ENDS composed of different e-liquid combinations: vegetable glycerin (VG), propylene glycol (PG), nicotine (nic), and benzoic acid (BA). The tested mixtures included PG, PG + nic + BA, VG, VG + nic + BA, 30/70 PG/VG, and 30/70 PG/VG + nic + BA. A carboxen polydimethylsiloxane fiber for a solid-phase microextraction was placed in a gas cell to trap benzene emitted from a Sub-Ohm Minibox C device. Benzene was adsorbed on the fiber during the puffing process and for an extra 15 min until it reached equilibrium, and then it was determined using gas chromatography-mass spectrometry. Benzene was quantified in VG but not in PG or the 30/70 PG/VG mixtures. However, benzene concentration increased in all tested mixtures upon the addition of nicotine benzoate salt. Interestingly, benzene was emitted at the highest concentration when BA was added to PG. However, lower concentrations were found in the 30/70 PG/VG and VG mixtures with BA. Both VG and BA are sources of benzene. Enhanced emissions, however, are mostly noticeable when BA is mixed with PG and not VG.

Comprehensive improvement of nutrients and volatile compounds of black/purple rice by extrusion-puffing technology.

Black/purple rice is a pigmented rice variety that contains high levels of anthocyanins, flavonoids, and other valuable bioactive compounds. Owing to its robust anti-inflammatory and antioxidant properties, black/purple rice exerts a beneficial effect on human health. Extrusion puffing technology has emerged as a promising means of improving rice flavor with lesser effect on nutrient content. In this study, metabolomics approach was used to conduct comprehensive metabolomics analyses aimed at examining the impact of extrusion puffing on black/purple rice nutritional value and flavor. Firstly, the basic nutrient composition contents and extrudate characteristics of black/purple rice and Extrusion puffed black/purple rice were conducted. Then metabolomics profiling analyses of black/purple rice samples were performed to explore the impact of the extrusion puffing process on nutrient content and bioactive properties, in which we quantitatively determined the flavonoids and evaluated relative contents of volatile compounds. These analyses revealed that following extrusion puffing, black/purple rice exhibited significant improvements in the content of nutrients including flavonoids, minerals, and proteins together. Extrusion puffing additionally increased the diversity of volatile compounds within black/purple rice. These results suggest that extrusion puffing represents an effective means of substantially improving the functional and nutritional properties of black/purple rice, offering beneficial effects on consumer health. Overall, these data provide novel insights into the quality of extrusion puffed black/purple rice that will guide future efforts to establish how extrusion puffing can alter the nutrient content in a range of foods, thereby supporting the further development of a range of healthy food products.

Modifying the particle density of cocoa powder using puffing method for sustainable consumption and production

Flavanols contained in cocoa have several benefits for the human body. However, cocoa consumption in Indonesia is still considered low. Improving the production and quality improvements of cocoa could lead to the sustainable consumption and production of cocoa plant. One main drawback of beverage product that contains cocoa powder is that the cocoa powder precipitates easily, which can reduce the taste and health benefits of cocoa powder. Hence, this research aims to develop a method to increase the buoyancy of cocoa powder in beverages. This study used cocoa powder products (Windmolen and van Houten brands). The puffing chamber with pressure control was made from a cylindrical tube. Sensory test of the cocoa powder samples was performed. Furthermore, statistical analysis was performed on the data obtained from the sensory test. Our results showed that the cocoa powder samples undergoing the puffing process with higher pressure and longer time had a lower moisture content. In addition, the statistical analysis showed that the puffing process did not significantly affect the preference for the taste of cocoa powder. Overall, the puffing method decreased the density of cocoa particles, so the particles would be distributed in the liquid evenly.

Effect of Coating on Physico-Chemical Characteristics of Puffed Wheat Grains

Abstract Durum wheat (Triticum turgidum) is used for the production of various ready-to-eat products such as breakfast cereals, puffed grains, and extruded products. Technological processes of grain processing and the addition of different ingredients cause changes in the physical and chemical properties of the product, which give puffed grains a unique porous structure and change their nutritional value. This study aimed to evaluate the effect of coating on the physico-chemical characteristics of puffed wheat grains depending on the coating material. The study revealed that the application of coating increased dry matter and thousand-kernel weight (TKW). Water activity decreased in puffed grain without coating (BZ), and puffed grain with whey powder (MC) compared to wheat grain. The reduction in the moisture content increased the crispiness of product. Application of coating led to a decrease in the hardness of both MC and puffed wheat grain with vanillin and sugar (BV). Applying additives to the product’s surface led to a decrease in the water absorption index (WAI). The water solubility index (WSI) increased in the MC and BV samples. Samples BZ, BV and MC had higher L* (lightness) values than wheat grains because the puffing process expanded the cells, confirmed by scanning electron microscopy, and caused starch gelatinisation. The a* (redness) value of wheat was greater than that of BZ, BV and MC, which may be due to the partial removal of the outer layer of wheat grains. The milled samples of BZ, BV and MC were slightly darker, having lower L* values, compared to unprocessed wheat grain.

Effects of explosion puffing on surimi-starch blends: Structural characteristics, physicochemical properties, and digestibility

This study investigated the influence of different explosion puffing pressures (0.6 MPa-1.0 MPa) on the structural characteristics, physicochemical characteristics, and digestibility of surimi-starch blends. With increased explosion puffing pressures, the starch granules attached to the protein network and bound to the protein increasingly tight. The results of X-ray diffraction and Fourier-transform infrared spectroscopy (FTIR) showed that explosion puffing destroyed ordered starch molecule chains resulting in a starch structure chaos. In addition, explosion puffing reduced the secondary structure number of surimi proteins by loosening intramolecular hydrogen bonds. The explosion puffing decreased the digestibility of puffed surimi-starch blends, while increased the resistant starch content. Maillard reaction in the puffing process led to the browning of the surimi-starch blends. the surimi-starch blends exhibited the optimal qualities with homogeneous pore structure, good color (70.11), excellent crispness (25.55 mm), desirable hardness (1967.57 Pa), and high expansion rate (398.85%) at explosion pressure 0.8 MPa. Our findings provide a reference for processing non-fried high-protein puffed food.

The manufacturing of puffed corn flakes: Optimization, characterization and sensory attributes

Corn snacks are growing worldwide in food market. Puffing is an alternative processing technology to improve the characteristics of food products with the benefit of low oil. However, the puffing process of corn flakes is rarely studied in recent research. Thus, the objective of this study is to optimize the conditions of puffing with the raw material of corn grit and compare with extrusion, frying and baking process in the aspect of microstructure and sensory evaluation of corn flakes. The results showed that the optimized conditions of puffing flakes were 6 min of pretreated time, 226 °C of puffing temperature, 9 s of puffing time. And the experimental responses of crispy, hardness and browning index at the optimized conditions are 0.73±0.05 nm, 1317.52±23.14 g, 56.91±0.87, respectively. To compared with other traditional process that manufacture the corn flakes, the microstructure and sensory evaluation are applied. The microstructure of puffing method presented porous and spongy structure with numerous cavities in small sizes. For the sensory evaluation, the score of taste, texture, color and overall acceptability applied for puffing is the highest. In conclusion, the puffing would be a novel technology to manufacture tasty corn flakes in the snack food industry. Keywords: Corn flakes; Optimization; Puffing; Response surface methodology; Sensory attributes

Increases in Ginsenoside Rg3, Compound K, and Antioxidant Activity of Cultivated Wild Panax Ginseng (CWPG) by Puffing.

Cultivated wild Panax ginseng (CWPG) has been reported to have a higher content of ginsenoside than normal Panax ginseng. This study was carried out to increase the antioxidant activity and active ingredients by the puffing process. Therefore, effects of moisture content and pressure conditions on the antioxidant activity and active ingredients of CWPG were investigated. Extraction yield and crude saponin content were decreased at all moisture contents with increasing pressure. HPLC analysis showed that the contents of ginsenoside Rg3 and compound K were increased by puffing when the pressure increased. Antioxidant properties, total phenolic content (TPC) and total flavonoid content (TFC) were increased by puffing. The correlation between color change and antioxidant activity showed the greatest correlation with the decrease of L value. It is expected that the progress of this study will play an important role in the international market of high-value-added food using CWPG.

Puffing characteristics of berry slice under continuous microwave puffing conditions

To elucidate the puffing characteristics of the berry slice under continuous microwave conditions, heat and mass transfer and deformation of slices were investigated based on the models of coupled multi-physics fields involving electromagnetic heating, heat and mass transfer and solid mechanics. The results indicated that transmission mode of microwaves in a microwave cavity determined the electric field distribution inside slices with interior focusing phenomenon described by higher temperature and lower moisture content at the central region of slices than that of edge. The berry slice volume showed a “invisible-rapid-maintained” deformation under the synergistic effects of temperature, moisture and internal pressure with sample movement. This study may provide guidance for the elucidation of microwave puffing process of the moving slice and the underlying applications such as technology optimization and quality control of slices like berry. Novelty impact statement This work investigates the puffing characteristics of the moving berry slices under a continuous microwave dryer, and elucidates the heat and mass transfer and deformation process of berry slices by means of experiment and simulation. The distribution of alternating electric field profiles with high and low levels determine the absorption of microwave energy, heat and mass transfer in berry slices to induce the volume deformation and uneven distribution. The volume of berry slices laid on moving conveyor belt under continuous microwave puffing undergoes three deformation trends as invisible change followed by rapid expansion till desired shape.

Optimization of traditional puffing of a nutritious local grain (Amaranthus spp.) and development of a scalable business model supporting community health

Promoting and encouraging use of diverse nutritious grains is not only healthy but can also, provide livelihood opportunities to rural groups.The study attempted a farm to table approach by standardizing traditional puffing of amaranth grains and training women for a batch scale process to develop a scalable business model. Manual puffing process for amaranth grains was developed and standardized. Puffed samples were compared with market samples for sensory parameters, expansion ratio, nutritive composition and sodium content using SPSS and MS-excel statistical analysis.It was observed that direct heat puffing of cleaned and sieved grains on inclined karahis, provided good puffing efficiency (approximate 94%). Manually puffed grains had similar nutritional values and were crunchier than the market samples. Though, the machine puffed samples had better expansion ratio but, a higher sodium content of 1349.01 ± 0.073 and 1346.15 ± 0.014 mg/100g was reported when compared with manually puffed grains having only 135.3 ±0.037mg/100g of sodium. Individual capacities of women were observed for six months to develop a learning curve to understand production efficiencies. The production capacity of women ranged from 2250 kg to 3250 kg per month. A traceable model was developed, by procuring grains from small and marginal farmers, and processing undertaken by trained women groups. A production of 34, 936 kg of puffed grain in the FY 2020-21 indicated a potential for a sustainable business supporting livelihoods and health.

Local contributions of resolved and subgrid turbulence-radiation interaction in LES/presumed FDF modelling of large-scale methanol pool fires

The present study aims to quantify individual contributions to turbulence-radiation interaction (TRI) in LES of large methanol pool fires with diameters ranging from 1m to 4m. These simulations feature a steady laminar flamelet (SLF)/presumed Filtered Density Function (FDF) combustion model and the Rank Correlated Full Spectrum k-distribution (RC FSK) for spectral gas radiation. This quantification has a fundamental interest to, on the one hand, understand how these contributions affect the radiative heat transfer from the flame to the surroundings that controls fire growth in industrial fires and, on the other hand, to provide guidance for the development of simplified models for TRI. This analysis is accomplished by exercising a well-validated fire model and using a scaling strategy that preserves the relative contributions of resolved-scale and subgrid-scale (SGS) scalar fluctuations. Large-scale non-luminous pool fires feature large optical thicknesses that increase significantly with the pool diameter. As a result, applying the optically-thin fluctuation approximation (OTFA) leads to a noticeable overestimation of the global radiative loss. The fire plume dynamics is governed by the puffing process whose frequency decreases with the pool size, and, in turn, affects the levels of turbulent intensity. As a result, emission TRI increases in the continuous flame and decreases in the high intermittent flame regions. The contribution of SGS emission TRI to global emission TRI becomes progressively dominant as the pool size increases. The largest contributions to both resolved-scale and SGS emission TRI are the temperature self-correlation and the absorption coefficient-temperature cross correlation, although this latter becomes negligible at the subgrid scale for pool diameters larger than 1m. In addition, the SGS absorption-coefficient self-correlation is also found to be negligible.

Ginsenosides Conversion and Anti-Oxidant Activities in Puffed Cultured Roots of Mountain Ginseng

CRMG (Cultured Roots of Mountain Ginseng) have the advantages in scale-up production, safety, and pharmacological efficacies. Though several methods are available for the conversion of major to minor ginsenosides, which has more pharmacological activities, a single step process with high temperature and pressure as a puffing method took place in this study to gain and produce more pharmacologically active compounds. Puffed CRMG exhibited an acceleration of major ginsenosides to minor ginsenosides conversions, and released more phenolic and flavonoid compounds. HPLC analysis was used to detect a steep decrease in the contents of major ginsenosides (Re, Rf, Rg1, Rg2, Rb1, Rb2, Rb3, Rc and Rd) with increasing pressure; on the contrary, the minor ginsenosides (20 (S, R)-Rg3, Rg5, Rk1, Rh1, Rh2, Rg6, F4 and Rk3) contents increased. Minor ginsenosides, such as Rg6, F4 and Rk3, were firstly reported to be produced from puffed CRMG. After the puffing process, phenolics, flavonoids, and minor ginsenoside contents were increased, and also, the antioxidant properties, such as DPPH inhibition and reducing the power of puffed CRMG, were significantly enhanced. Puffed CRMG at 490.3 kPa and 588.4 kPa had a low toxicity on HaCaT (immortalized human epidermal keratinocyte) cells at 200 μg/mL, and could significantly reduce ROS by an average of 60%, compared to the group treated with H2O2. Therefore, single step puffing of CRMG has the potential to be utilized for functional food and cosmeceuticals.

Effect of Sand-Frying-Triggered Puffing on the Multi-Scale Structure and Physicochemical Properties of Cassava Starch in Dry Gel.

This study revealed the underlying mechanisms involved in the puffing process of dried cassava starch gel by exploring the development of the puffed structure of gel upon sand-frying, chiefly focused on the changes in the multi-scale structure and the physicochemical properties of starch. The results suggested that the sand-frying-induced puffing proceeded very fast, completed in about twenty seconds, which could be described as a two-phase pattern including the warming up (0~6 s) and puffing (7~18 s) stages. In the first stage, no significant changes occurred to the structure or appearance of the starch gel. In the second stage, the cells in the gel network structure were expanded until burst, which brought about a decrease in moisture content, bulk density, and hardness, as well as the increase in porosity and crispness when the surface temperature of gel reached glass transition temperature of 125.28 °C. Upon sand-frying puffing, the crystalline melting and molecular degradation of starch happened simultaneously, of which the latter mainly occurred in the first stage. Along with the increase of puffing time, the thermal stability, peak viscosity, and final viscosity of starch gradually decreased, while the water solubility index increased. Knowing the underlying mechanisms of this process might help manufacturers produce a better quality of starch-based puffed products.

The effect of explosive puffing process after fermentation on ginsenosides conversion

In this study, explosion puffing was attempted to convert ginsenosides after fermentation. Fermented ginseng was used to measure changes in ingredients including ginsenosides before and after explosive puffing, and changes in radical scavenging capacity and intestinal absorption were evaluated. Explosive puffing process (7.5 and 10 kgf cm−2) after fermentation showed significant changes in the content of major and minor ginsenosides and the radical scavenging activities compared to normal or fermentation ginseng. In the case of ginseng treated with puffing after fermentation, the amount of polyphenols absorbed into the intestine tended to increase significantly compared to normal or fermentation ginseng. In the transmittance of ginsenoside metabolite, explosive puffed ginseng showed a significant increase in transmittance after 3 h compared to normal and fermentation-treated ginseng. These results are expected that ginseng with increased absorption rate by explosive puffing treatment after fermentation will have higher activity than existing ginseng or fermented ginseng.

Comparison of explosion puffing drying with other methods on the physicochemical properties and volatiles of yam (Dioscorea opposita thunb.) chips through multivariate analysis

Crisp yam chips were produced using hot air drying (AD), vacuum drying (VD), freeze drying (FD), and explosion puffing drying (EPD). As a result, the reducing sugar, total polyphenol and vitamin C contents, rehydration rate and volume ratio were well retained in freeze-dried chips with explosion puffing-dried chips following closely behind, which exhibited a higher total soluble solids content (TSS) and crispness. The microstructure of explosion puffing-dried chips showed distinct cell wall breakage and cell expansion, indicating the release of more TSSs and a relatively high hardness and crispness. Based on physicochemical chip properties, FD and EPD could be distinguished from the other drying methods, and the characteristic physicochemical properties of explosion puffing-dried yam chips were identified as the hardness and TSS level using multivariate analysis. Furthermore, 43 volatile compounds were isolated and identified in fresh yam and dried yam chips using headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS). Based on the volatile compositions of the samples, oct-1-en-3-ol was identified as the major volatile compound in fresh yam, and the volatiles in the explosion puffing-dried chips were clearly distinguished from those in the other dried yam chips due to the unique puffing process.

Chemical and biological properties of puffed Dendrobium officinale extracts: Evaluation of antioxidant and anti-fatigue activities

Abstract Dendrobium officinale (D. officinale, DO) is a traditional medicinal herb used in China. Phytochemicals and its antioxidant activity of puffed dendrobium extract was measured for antioxidant capacity. Physiological mechanism on skeletal muscle was analyzed by blood glucose, lactic acid, glycogen and ATP content and mRNA gene expression. Antioxidant effect of the extract on liver were measured. The extraction yield and phytochemical contents in DO extract were increased by the change of puffing pressure. In addition, antioxidant activities creased after explosive puffing process. DO extract treated with explosive puffing at high dose was significantly prolonged in swimming time. The glycogen content of puffing DO at high dose was significantly different. The expression of the PGC1-α and the level of ATP in PHD was higher. Explosive puffing DO strongly improve fatigue resistance of mice correlated with inhibiting the depletion of glycogen stores, regulating oxidation related enzymes, and modulating the activation of PGC-1α.

Experimental study of injection characteristics under diesel’s sub/trans/supercritical conditions with various nozzle diameters and injection pressures

The supercritical fluid combustion technology was expected to enhance fuel-gas mixing and heat exchange management both in the application of automobile and marine engines. Considering the challenge and shortage of relevant researches, the transcritical injection experiment is conducted in a constant volume chamber to obtain the detailed knowledge about the effect of key factors, such as nozzle diameters, injection pressures and critical conditions, on injection and critical characteristics. A total of 216 experimental cases were operated to analyze the effect of three different injector nozzle diameters (100, 300, 350 μm), four injection pressures (60, 100, 140, 180 MPa) and nine ambient conditions, with two optical techniques (backlight illumination, schlieren imaging). The fuel injection characteristics are studied, where the spray structure is recorded, and the liquid length, R-parameter, spray volumes, cone angles as well as relevant empirical correlations are calculated to investigate the axial and radial dispersion. The results show that different critical conditions dominate the fuel spray to behave as different structures. The 350 μm nozzle produces a higher fuel mass flow rate than other nozzles to expand the side periphery region, while the 100 μm nozzle is prone to be dominated by ambient gas entrainment to strength the puffing process. The injection pressure has an insignificant effect on the liquid length, liquid volume and spray cone angles, but an increasing influence on the jet volume with higher pressures. Under supercritical condition, higher injection pressure can promote the fuel-gas mixing and hot gas entrainment in the downstream region.

Understanding puffing in a domestic microwave oven

AbstractThis work is intended to develop an overall understanding of puffing of a starch‐based snack in a home microwave oven, using primarily the microwave energy. Combination of experimental measurements was used, including dynamic mechanical thermal analysis, CT‐Scan, SEM, image processing, and measurement of temperature, moisture content, and expansion ratio. Effects of various product and process parameters on puffing, including those of pretreatment to produce the half product, were studied. Experimental data showed that the physicochemical processes contributing to crust formation were gelatinization of starch, migration of soluble ingredients to the surface, and shrinkage at the surface. A thicker material was harder to puff due to its increased mechanical resistance. Higher microwave power, leading to higher rate of evaporation, increased expansion. Evolution of mechanical properties of the crust greatly affected the final shape of the puffed product. In overall understanding, critical determinants of a puffing process were attributed to three material factors (reduced surface permeability, optimal moisture content, and deformability) and two process factors (intense heat and higher internal pressure from evaporation).