Effective strategies for reduction of oil content in deep-fat fried foods: A review

Improving the physicochemical quality and oxidative stability of deep-fried pork meatballs by coating with chitosan grafted gallic acid

The objective of this research was to examine the effectiveness of chitosan (CH)-gallic acid (GA) conjugate (CH-g-GA) as an edible coating in improving the physicochemical properties and oxidative stability of deep-fat fried pork meatballs. The meatballs were coated with either CH alone, a combination of CH and GA, or CH-g-GA before being fried at 180 °C for 5 min. The viscosity of the coating solutions influenced the amount of coating picked up by the meatballs, with higher viscosity coatings showing increased pickup. The application of chitosan-based coatings in deep-fried meatballs resulted in a decrease in moisture loss and oil uptake, as well as decreased b* values and hardness, while maintaining consistent cooking yield. Furthermore, compared to the control group, the chitosan-based coatings treatment significantly increased the ratio of immobilized water and decreased the ratio of free water (P < 0.05), as well as effectively inhibited lipid oxidation in deep-fried meatballs (P < 0.05). Among the different coatings tested, CH-g-GA coating exhibited the highest effectiveness. The research findings suggest that the CH-g-GA edible coating has significant potential in enhancing the overall quality of deep-fried meatballs.

Application of batter coating for modulating oil, texture and structure of fried foods: A review

Food surface modulation by batter coating is a promising approach to reduce the presence of oil in fried products. This review critically discussed the functionalities, mechanism of actions, rheology, ingredients of formulation, mathematical modeling of the process, cooking method, safety and regulatory aspects, physicochemical, thermal-microstructural characterization of batter coatings, and future research directions. Enormous list of ingredients could be used in preparation of oil-reducing viscoelastic batter coating that includes mostly flours, hydrocolloids, and starches. Bioactive compounds, enzymes, minerals, herbal extracts, baking agents, sugar alcohols, etc. could be incorporated in batter formulation to affect the taste and texture of coated products. Overall mass-transfer process of batter-coated fried foods could be characterized by several mathematical models (Fick, Newton, Page, Henderson & Pabis, modified Page, Arrhenius). Surface and internal microstructural characterization techniques, thermal probing, physicochemical characterization techniques and artificial intelligence can characterize different functionalities of batter coatings including oil reduction and textural evolution.

Developing an Acceptable Nixtamalised Maize Product for South African Consumers: Sensory, Survey and Nutrient Analysis

South Africa produces high-quality maize, yet food insecurity and malnutrition are prevalent. Maize is a staple for most South Africans and is often eaten as pap, gruel cooked from maize meal (corn flour) and water without diet diversification. Considering the reliance on maize in low-income communities, could nixtamalised maize products be developed that are nutritious, homemade and consumer-acceptable? Nixtamalisation could offer a solution. However, its acceptability and nutritional benefits remain in question. We aimed to develop a product using consumer-led methods. Consumer panels evaluated and selected products using overall acceptability (9-point hedonic scale), Just-About-Right (JAR) and penalty analysis. Consumer-acceptable nixtamalised chutney-flavoured maize chips were moderately liked (7.35) and reached acceptable JAR scores (74.2%). The nixtamalised products were liked and liked very much (56%), 61% of panel members agreed and strongly agreed to purchase and prepare, and 50% to consume nixtamalised products. Nutrient analysis of the chutney chips showed high energy (2302 kJ/100 g) and total fats (23.72), of which saturated fats were 11.47%. Total fibre (17.19 g/100 g), protein (6.64 g/100 g), calcium (163.3) and magnesium (53.67 g/100 g) were promising, while high phosphorous (566.00 mg/100 g) may indicate anti-nutrients present. Nixtamalisation can alleviate food insecurity and malnutrition in countries such as South Africa.

Comparative Analysis of Frying Performance: Assessing Stability, Nutritional Value, and Safety of High-Oleic Rapeseed Oils

Frying is a critical process in the food industry, where selecting appropriate vegetable oils is key to achieving optimal results. In this study, French fries were fried at 175 °C with five different oils, the changes in the physicochemical indexes and free radical scavenging rate of the oils during the frying process were investigated, and the most suitable oils for frying were identified through comparative analysis using principal component analysis (PCA). We assessed the frying performances of hot-pressed high-oleic-acid rapeseed oil (HHRO), cold-pressed high-oleic-acid rapeseed oil (CHRO), soybean oil, rice bran oil, and palm oil utilizing principal component analysis over an 18 h period. The HHRO and CHRO showed lower acid values (0.31, 0.26 mg/g), peroxide values (2.09, 1.96 g/100 g), p-anisidine values (152.48, 178.88 g/mL), and total polar compound percentages (27.60%, 32.10%) than other oils. Furthermore, both the HHRO and CHRO demonstrated enhanced free radical scavenging abilities, indicative of their higher antioxidant capacities, as corroborated by the PCA results. Benzopyridine, 3-monochloropropane-1,2-diol ester, squalene, tocopherols, and polyphenol from the HHRO and CHRO during frying were compared. A comprehensive examination of harmful substances versus nutrient retention during frying revealed that the HHRO contained fewer hazardous compounds, while CHRO retained more nutrients. Therefore, this study analyzes the oxidation regulation of HHRO in frying applications, highlights the prospects of HHRO for frying in terms of health and economy, and contributes valuable insights for informed vegetable oil selection within the food industry.

Modulation of fried spring roll wrapper quality upon treatment of batter with maltogenic amylase, transglutaminase and bromelain

BACKGROUND

Fried foods are favored for their unique crispiness, golden color and flavor, but they also face great challenge because of their high oil content, high calories and the existence of compounds such as acrylamide and polycyclic aromatic hydrocarbons. Long-term consumption of fried foods may adversely affect health. Therefore, it is necessary to explore fried foods with lower oil contents and a high quality to meet the demand.

RESULTS

A method of enzyme treatment was explored to investigate the effects of maltogenic amylase (MA), transglutaminase (TG) and bromelain (BRO) on the physicochemical properties of the batter and the quality of fried spring roll wrapper (FSRW). The results showed that the MA-, TG- or BRO-treated batters had a significant shear-thinning behavior, especially with an increase in viscosity upon increasing TG contents. FSRW enhanced its fracturability from 419.19 g (Control) to 616.50 g (MA-6 U g-1), 623.49 g (TG-0.75 U g-1) and 644.96 g (BRO-10 U g-1). Meanwhile, in comparison with BRO and MA, TG-0.5 U g-1 endowed batter with the highest density and thermal stability. MA-15 U g-1 and TG-0.5 U g-1 displayed FSRW with uniform and dense pores, and significantly reduced its oil content by 18.05% and 25.02%, respectively. Moreover, compared to MA and TG, BRO-50 U g-1 improved the flavor of FSRW.

CONCLUSION

MA, TG or BRO played a key role in affecting the physicochemical properties of the batter and the quality of FSRW. TG-0.5 U g-1 remarkly reduced the oil content of FSRW with a great potential in practical application. © 2024 Society of Chemical Industry.

A comprehensive review of the mechanism, changes, and effect of deep fat frying on the characteristics of restructured foods

Restructured foods are a blend of various ingredients that are dried or fried to obtain a ready-to-eat product. Several frying techniques have been employed viz., deep fat, microwave, vacuum, air, and spray frying. Deep-fat frying is the most common technique used for products that have improved texture and sensory characteristics. It facilitates various transformations that include starch gelatinization, protein denaturation, nutrient loss, non-enzymatic browning, lipid oxidation, etc. This physicochemical change alters both the product and the fried oil quality. The frying conditions will also influence the product characteristics and affect the properties of the fried product. This review focuses on the mechanisms and transformations during deep fat frying. The properties, namely physical, chemical, sensory, thermal, rheological, and microstructural changes of restructured foods were discussed. Thus, a better understanding of mechanisms and properties at optimum frying conditions would yield the desired product quality.

Thermomechanical transitions of meat-analog based fried foods batter coating

This study aimed to characterize the thermomechanical transitions of meat-analog (MA) based coated fried foods. Wheat and rice flour-based batters were used to coat the MA and fried at 180 °C in canola oil for 2, 4 and 6 min. Glass-transition-temperature (Tg) of the coatings were assessed by differential scanning calorimetry, directly after frying or after post-fry holding. Mechanical texture analyzer and X-ray microtomography were employed to assess textural attributes and internal microstructure, respectively. Batter-formulation substantially impacted the Tg of fried foods coating i.e., crust. Tg of fried foods crust were ranged between -20 °C to -24 °C. Tg was positively correlated with frying time and internal microporosity (%), whereas negatively correlated with moisture content. Internal microstructure greatly influenced the textural attributes (hardness, brittleness, crispiness). Post-fry textural stability considerably impacted by Tg. Negative Tg value explains post-fry textural changes (hard-to-soft, brittle-to-ductile, crispy-to-soggy) of MA-based coated products at room-temperature (25 °C) and under IR-heating (65 °C).

Review of formation mechanisms and quality regulation of chewiness in staple foods: Rice, noodles, potatoes and bread

Staple foods serve as vital nutrient sources for the human body, and chewiness is an essential aspect of food texture. Age, specific preferences, and diminished eating functions have broadened the chewiness requirements for staple foods. Therefore, comprehending the formation mechanism of chewiness in staple foods and exploring approaches to modulate it becomes imperative. This article reviewed the formation mechanisms and quality control methods for chewiness in several of the most common staple foods (rice, noodles, potatoes and bread). It initially summarized the chewiness formation mechanisms under three distinct thermal processing methods: water medium, oil medium, and air medium processing. Subsequently, proposed some effective approaches for regulating chewiness based on mechanistic changes. Optimizing raw material composition, controlling processing conditions, and adopting innovative processing techniques can be utilized. Nonetheless, the precise adjustment of staple foods' chewiness remains a challenge due to their diversity and technical study limitations. Hence, further in-depth exploration of chewiness across different staple foods is warranted.

Influence of key component interactions in flour on the quality of fried flour products

In the field of food, the interaction between various components in food is commonly used to regulate food quality. Starches, proteins, and lipids are ubiquitous in the food system and play a critical role in the food system. The interaction between proteins, starches, and lipids components in flour is the molecular basis for the formation of the classical texture of dough, and has a profound impact on the processing properties of dough and the quality of flour products. In this article, the composition of the key components of flour (starch, protein and lipid) and their functions in dough processing were reviewed, and the interaction mechanism of the three components in the dynamic processing of dough from mixing to rising to frying was emphatically discussed, and the effects of the components on the network structure of dough and then on the quality of fried flour products were introduced. The analysis of the relationship between dough component interaction, network structure and quality of fried flour products is helpful to reveal the common mechanism of quality change of fried flour products, and provide a reference for exploring the interaction of ingredients in starch food processing.

Restructuring plant-derived composites towards the production of meat-analog based coated fried food

This study utilized different plant-based composites to develop restructured meat-analog (MA). Physicochemical, thermal, mechanical, structural, and sensory properties of formulated MA as well as batter-coated fried MAs were studied, and compared with a commercial product. Protein (23.27-24.68 %), moisture (57.05-58.78 %), pH (7.19-7.57), color (L:64.76-66.84, a:0.62-1.98, b:18.84-20.49), and textural (MF:0.22-0.52 N, GF:0.07-0.24 N/sec, FA:0.74-1.92 N.sec) attributes of formulated MAs were substantially impacted by the ratio of soy-protein-isolate (SPI) and wheat-gluten (WG). Incorporation of higher WG and lower SPI resulted in the formation of chicken-like fibrous and porous structure, hence, increased consumers acceptability of MA-based coated fried products. Microporosity (crust:51.14-58.35 %, core: 63.57-71.55 %), surface opening (5.67-14.75 %), and fractal dimension (2.586-2.402) of coated fried MAs were dependent on the formulation of batter-coating. MA-based coated fried products surface moisture-fat (SMR:0.51-187.20 au; SFR: 2.01-20.17 au) profile significantly (p < 0.05) varied with the formulations of batter-coating. Negative glass-transition-temperature (around -23 °C) is prime concern for MA-based fried products stability at room environment.

Potential of polyphenols from Ligustrum robustum (Rxob.) Blume on enhancing the quality of starchy food during frying

The increasing concerns about health have led to a growing demand for high-quality fried foods. The potential uses of Ligustrum robustum (Rxob.) Blume, a traditional tea in China, as natural additives to enhance the quality of starchy food during frying was studied. Results indicated that L. robustum polyphenols extract (LREs) could improve the quality of fried starchy food, according to the tests of color, moisture content, oil content, texture property, and volatile flavor. The in vitro digestion results demonstrated that LRE reduced the final glucose content from 11.35 ± 0.17 to 10.80 ± 0.70 mmol/L and increased the phenolic content of fried starch foods from 1.23 ± 0.04 to 3.76 ± 0.14 mg/g. The appearance and polarizing microscopy results showed that LRE promoted large starch bulges on the surface of fried starchy foods. Meanwhile, X-ray diffraction results showed that LRE increased the intensity of characteristic diffraction peak of fried starch with a range of 21.8%-28%, and Fourier transform infrared results showed that LRE reduced the damage to short-range order structure of starch caused by the frying process. In addition, LRE increased the aggregation of starch granules according to the SEM observation and decreased the enthalpy of starch gelatinization based on the differential scanning calorimetry results. The present results suggest that LREs have the potential to be utilized as a natural additive for regulating the quality of fried starchy food in food industries. PRACTICAL APPLICATION: The enhancement of L. robustum polyphenols on the quality of starchy food during frying was found, and its mechanisms were also explored. This work indicated that L. robustum might be used as a novel economic natural additive for producing high-quality fried foods.

Recent advances in enzymatic modification techniques to improve the quality of flour-based fried foods

Flour-based fried foods are among the most commonly consumed foods worldwide. However, the sensory attributes and nutritional value of fried foods are inconsistent and unstable. Therefore, the creation of fried foods with desirable sensory attributes and good nutritional value remains a major challenge for the development of the fried food industry. The quality of flour-based fried foods can sometimes be improved by physical methods and the addition of chemical modifiers. However, enzyme modification is widely accepted by consumers due to its unique advantages of specificity, mild processing conditions and high safety. Therefore, it is important to elucidate the effects of enzyme treatments on the sensory attributes (color, flavor and texture), oil absorption and digestibility of flour-based fried foods. This paper reviews recent research progress in utilizing enzyme modification to improve the quality of flour-based fried foods. This paper begins with the effects of common enzymes on the physicochemical properties (rheological property, retrogradation property and specific volume) of dough. Based on the analysis of the mechanism of formation of sensory attributes and nutritional properties, it focuses on the application of amylase, protease, transglutaminase, and lipase in the regulation of sensory attributes and nutritional properties of flour-based fried foods.

Effect of cinnamon powder on quality attributes and off-flavor in fried chicken drumsticks made from long-term thawed Korean native chicken

The effect of cinnamon powder on the quality and mitigation of off-flavor in fried chicken drumsticks made from long-term thawed Korean native chicken (Woorimatdag No. 1, WRMD1) was investigated. The WRMD1 drumsticks were categorized into 5 groups: conventional thawing (16 h, CT), long-term thawing (48 h, LT), cinnamon powder added into 'LT' as marinade (0.03%, CM) or incorporated into the batter (1.35%, CB), and long-term thawing with cinnamon powder incorporated both in the marinade and batter (0.03% + 1.35%, CMB). The crude fat content was significantly higher in the CT and CMB than that of the CB. The CM, CB, and CMB showed significantly lower levels of 2-thiobarbituric acid reactive substance compared with the CT and LT. The predominant fatty acids in all treatments were C18:1n9, C18:2n6, and C16:0. The LT displayed lower total unsaturated fatty acid content than the CT (P < 0.05). The CM effectively decreased lipid oxidative volatiles, such as 1-octanol, 1-octen-3-ol, and 2-octen-1-ol, (E), in the LT (P < 0.05). Both the CM and CB showed an inclination to increase specific pyrazines associated with pleasant notes compared with the LT, and showed higher levels of pyrazines, such as pyrazine, 2-ethyl-6-methyl-, and pyrazine, 3-ethyl-2,5-dimethyl-, than those of the CMB (P < 0.05). The CM contained higher levels of 2,3-butanedione when compared with the other groups (P < 0.05). Multivariate analysis demonstrated that cinnamon had an effect in discriminating the treatment groups with cinnamon addition from both the CT and LT, whereas the CM, CB, and CMB formed distinct clusters. The CM and CMB received significantly higher aroma scores from panelists in comparison to the other groups. These findings suggest that the CM (0.03% cinnamon powder) can be used to enhance the aroma in fried WRMD1 drumsticks by reducing or masking the off-flavor volatiles associated with long-term thawing.

Effect of starch granule size on the properties of dough and the oil absorption of fried potato crisps

Starch is a key element in fried potato crisps, however, the effect of starch granule size on oil absorption of the product have yet to be fully investigated. The study explored the impact of starch granule size on both the dough characteristics and oil absorption in potato crisps. The dough composed of small-sized potato granules showed more compact and uniform network system. Additionally, X-ray Microscope analysis showed that potato crisps prepared with small-sized potato granules had limited matrix expansion and fewer pores, cracks, and voids. The small-sized potato and small-sized wheat starches granule addition crisps displayed a significantly greater average cell thickness (52.05 and 53.44 μm) than other samples, while exhibiting notably lower average porosity (61.37 % and 60.28 %) compared to other samples. Results revealed that potato crisps with medium and small potato granules had 12.91 % and 21.92 % lower oil content than those containing large potato starch. Potato crisps with B-type wheat starch showed 16.36 % less oil absorption than those with A-type wheat starch. Small-sized starches significantly influence the dough structure and contribute to the reduction of oil absorption in fried products. The generated insights may provide monitoring indexes for cultivating potato varieties with low oil absorption.

Dissecting Maillard reaction production in fried foods: Formation mechanisms, sensory characteristic attribution, control strategy, and gut homeostasis regulation

Foods rich in carbohydrates or fats undergo the Maillard reaction during frying, which promotes the color, flavor and sensory characteristics formation. In the meanwhile, Maillard reaction intermediates and advanced glycation end products (AGEs) have a negative impact on food sensory quality and gut homeostasis. This negative effect can be influenced by food composition and other processing factors. Whole grain products are rich in polyphenols, which can capture carbonyl compounds in Maillard reaction, and reduce the production of AGEs during frying. This review summarizes the Maillard reaction production intermediates and AGEs formation mechanism in fried food and analyzes the factors affecting the sensory formation of food. In the meanwhile, the effects of Maillard reaction intermediates and AGEs on gut homeostasis were summarized. Overall, the innovative processing methods about the Maillard reaction are summarized to optimize the sensory properties of fried foods while minimizing the formation of AGEs.

Effects of frying on the surface oil absorption of wheat, potato, and pea starches

The effects of structural changes on surface oil absorption characteristics of wheat starch, pea starch and potato starch during frying under different water content (20%, 30%, 40%, 50%) were studied. Fried potato starch with a 40% water content exhibited the highest surface oil content. When the initial moisture content reached 30%, the scattering intensity of the crystal layer structure decreased for wheat and pea starches, while the scattering peak for potato starch completely disappeared. At 40% moisture content, the amorphous phase ratio values for fried potato, wheat and pea starches were 13.50%, 11.78% and 11.24%, respectively, and the nitrogen adsorption capacity of fried starch decreased in turn. These findings that the structure of potato starch was more susceptible to degradation compared to pea starch and wheat starch, resulting in higher surface oil absorbed by potato starch during frying process.

Changes in the Physicochemical Properties and Microbial Communities of Air-Fried Hairtail Fillets during Storage

This study assessed the physicochemical properties of air-fried hairtail fillets (190 °C, 24 min) under different storage temperatures (4, 25, and 35 °C). The findings revealed a gradual decline in sensory scores across all samples during storage, accompanied by a corresponding decrease in thiobarbituric acid reactive substances (TBARS) and total viable count over time. Lower storage temperatures exhibited an effective capacity to delay lipid oxidation and microbiological growth in air-fried hairtail fillets. Subsequently, alterations in the microbiota composition of air-fried hairtail fillets during cold storage were examined. Throughout the storage duration, Achromobacter, Escherichia-Shigella, and Pseudomonas emerged as the three dominant genera in the air-fried hairtail samples. Additionally, Pearson correlation analysis demonstrated that among the most prevalent microbial genera in air-fried hairtail samples, Achromobacter and Psychrobacter exhibited positive correlations with the L* value, a* value, and sensory scores. Conversely, they displayed negative correlations with pH, b* value, and TBARS. Notably, air-fried samples stored at 4 °C exhibited prolonged freshness compared with those stored at 25 °C and 35 °C, suggesting that 4 °C is an optimal storage temperature. This study offers valuable insights into alterations in the physicochemical properties and microbial distribution in air-fried hairtail fillets during storage, facilitating the improvement of meat quality by adjusting microbial communities in air-fried hairtail fillets.

Oil Frying Processes and Alternative Flour Coatings: Physicochemical, Nutritional, and Sensory Parameters of Meat Products

The frying process changes can be desirable and undesirable, involving the physicochemical, nutritional, and sensory aspects, depending on the food and oil properties and the frying process. In this context, alternative flours emerge as a strategy for adding value to the food since they are rich in fiber, vitamins, and minerals, contributing to the variability of ingredients and the full use of food, including residues such as seeds and husks. This narrative review aims to gather current scientific data addressing the alternative flour coatings on breaded meat, mainly chicken, products to evaluate the effects on fried products' nutritional value, physicochemical parameters, and sensory attributes. Scopus, Science Direct, Springer, and Web of Science search bases were used. This review showed that alternative flours (from cereals, legumes, fruits, and vegetables) used as coatings increase water retention and reduce oil absorption during frying, increase fibers and micronutrient content, which are not present in sufficient quantities in commonly used flours due to the refining process. These flours also reduce gluten consumption by sensitive individuals in addition to favoring the development of desirable sensory characteristics to attract consumers. Therefore, frying processes in oil promote a reduction in humidity, an increase in oil absorption and energy content, and a decrease in vitamin content. In this context, coatings based on alternative flours can reduce these adverse effects of the frying process.

Acrylamide formation in air-fried versus deep and oven-fried potatoes

Introduction

Present study investigates the effects of different home pre-treatment processes and cooking techniques on the acrylamide content of fried potatoes.

Methods

Potato sticks were prepared in two different pre-treatment ways (washing and soaking) and cooked with three other techniques (air frying, deep frying, and oven frying). Acrylamide analyses were performed on cooked potatoes using an LC-MS/MS method.

Results

The highest acrylamide content was found in potatoes cooked using the air fryer (12.19 ± 7.03 μg/kg). This was followed by deep frying (8.94 ± 9.21 μg/kg) and oven frying (7.43 ± 3.75 μg/kg). However, the difference between the acrylamide contents of the potatoes according to the cooking methods was not statistically significant. The acrylamide content of the potatoes that were subjected to soaking in all three ways was lower than the potatoes that were not soaked and only washed. In the deep-frying method, it was found statistically significant that the soaked potatoes contained less acrylamide (p = 0.029).

Discussion

It is important to highlight the relatively low acrylamide levels found in oven-frying, lower than air frying in both washing and soaking groups in the present study. Although air fryers, which have become widely used as an alternative to deep frying in recent years, provide French fries with less oil, their role in the formation of acrylamide should be further investigated.

A review of different frying oils and oleogels as alternative frying media for fat-uptake reduction in deep-fat fried foods

Purpose

This review aims to examine the potential of oleogels as a frying medium to decrease oil absorption during deep-frying and enhance the nutritional and energy content of foods. By investigating the factors influencing oil incorporation during deep-frying and examining the application of oleogels in this process, we seek to provide insights into using oleogels as an alternative to traditional cooking oils.

Scope

Deep-frying, a widely used cooking method, leads to the retention of large amounts of oil in fried food, which has been associated with health concerns. To address this issue, researchers have investigated various methods to minimize oil absorption during frying. One promising approach is the use of oleogels, which are thermo-reversible, three-dimensional gel networks formed by entrapment of bulk oil with a low concentration (<10% of weight) of solid lipid materials known as oleogelators. This review will focus on the following aspects: a) an overview of deep-fried foods, b) factors influencing oil uptake and underlying mechanisms for oil absorption during deep-frying, c) the characterization and application of different frying oils and their oleogels in deep-fried foods, d) components of the oleogel system for deep-frying, and e) the health impact, oxidative stability, and sensory acceptability of using oleogels in deep-frying.

Key findings

The review highlights the potential of oleogels as a promising alternative frying medium to reduce fat absorption in deep-fried foods. Considering the factors influencing oil uptake during deep-frying, as well as exploring the properties and applications of different frying oils and their oleogels, can result in improved product qualities and heightened consumer acceptance. Moreover, oleogels offer the advantage of lower fat content in fried products, addressing health concerns associated with traditional deep-frying methods. The capacity to enhance the nutritional and energy profile of foods while preserving sensory qualities and oxidative stability positions oleogels as a promising choice for upcoming food processing applications.

Characteristics of Highland Barley-Wheat Composite Flour and Its Effect on the Properties of Coating Batter and Deep-Fried Meat

Highland barley flour-based coating batter has rarely been reported, although highland barley flour is promising due to its high β-glucan and amylose content. In this study, highland barley flour was used to substitute 40% to 80% of wheat flour to form a highland barely-wheat composite flour used in the coating batter. The characteristics of the highland barley-wheat composite flour and its effect on the properties of coating batter and deep-fried meat were analyzed. Results showed that the composite flour significantly improved water holding capacity, oil absorbing capacity, and water solubility index. In contrast, no significant change was observed in the water absorption index or swelling power. The incorporation of highland barley flour significantly changed the pasting properties of the composite flour. Compared with the wheat flour, the viscosity and the pickup of the coating batter made with composite flour increased from 4905 Pa·s and 0.53% to more than 12,252 Pa·s and 0.63%, respectively, and its water mobility decreased. These changes were closely related to the substitution rate of highland barley flour. The composite flour significantly increased the moisture content from 27.73% to more than 33.03% and decreased the oil content of the crust from 19.15% to lower than 16.44%, respectively. It decreased L* and increased a* of the crust and decreased the hardness, adhesiveness, and springiness of the deep-fried meat. A spongy inner structure with a flatter surface was formed in all composite flour-based crusts, and the substitution rate influenced the flatness of the crust. Thus, highland barley flour could be used for batter preparation with partial substitution, enhancing the quality of deep-fried meat and acting as an oil barrier-forming ingredient for fried batter foods.

A review on the frying process: Methods, models and their mechanism and application in the food industry

Frying is one of the most popular and traditional processes used in the food industry and food services to manufacture products that are high in quality and with unique sensory characteristics. The most common method of frying is deep-fat frying, used worldwide due to its distinct flavor profile and sensory aspects, which leads to physio-chemical changes at both macro and micro levels. One of the major concerns with deep-fried foods is their high oil content, and a variety of metabolic disorders can be caused by overconsumption of these foods, including heart disease, obesity, and high cholesterol. Due to their enticing organoleptic properties with their delicious flavor, pleasing mouthfeel, and unique taste, making them irresistible, it is also responsible for undesirable and unacceptable characteristics for consumers. Oil absorption can be reduced by developing novel frying methods that limit the amount of oil in products, producing products with fewer calories and oil while maintaining similar quality, flavor, and edibility. In addition, different pretreatments and post-frying treatments are applied to achieve a synergistic effect. The transfer of mass and heat occurs simultaneously during frying, which helps to understand the mechanism of oil absorption in fried food. Researchers have discovered that prolonged heating of oils results in polar compounds such as polymers, dimers, free fatty acids, and acrylamide, which can alter metabolism and cause cancer. To reduce the oil content in fried food, innovative frying methods have been developed without compromising its quality which also has improved their effect on human health, product quality, and energy efficiency. The aim is to replace the conventional frying process with novel frying methods that offer fried food-like properties, higher nutritional value, and ease of use by replacing the conventional frying process. In the future, it might be possible to optimize frying technologies to substantially reduce fried foods' oil content. This review focuses on a detailed understanding of different frying techniques and attempts to focus on innovative frying techniques such as vacuum frying, microwave cooking, and hot-air frying that have shown a better potential to be used as an alternative to traditional frying.

Application of guar (Cyamopsis tetragonoloba L.) gum in food technologies: A review of properties and mechanisms of action

With the world continuing to push toward modernization and the consumption of processed foods growing at an exponential rate, the demand for texturizing agents and natural additives has also risen as a result. It has become increasingly common to use thickening agents in food products to modify their rheological and textural properties and enhance their quality characteristics. They can be divided into (1) animal derived (chitosan and isinglass), (2) fermentation produced (xanthan and curdlan), (3) plant fragments (pectin and cellulose), (4) seaweed extracts (agar and alginate), and (5) seed flours (guar gum and locust bean gum). The primary functions of these materials are to improve moisture binding capacity, modify structural properties, and alter flow behavior. In addition, some have another responsibility in the food sector, such as the main ingredient in the delivery systems (encapsulation) and nanocomposites. A galactomannan polysaccharide extracted from guar beans (Cyamopsis tetragonolobus), known as guar gum (GG), is one of them, which has a wide range of utilities and possesses popularity among scientists and consumers. In the world of modernization, GG has found its way into numerous industries for use in food, cosmetics, pharmaceuticals, textiles, and explosives. Due to its ability to form hydrogen bonds with water molecules, it imparts significant thickening, gelling, and binding properties to the solution as well as increases its viscosity. Therefore, this study is aimed to investigate the characteristics, mechanisms, and applications of GG in different food technologies.

Global nutritional challenges of reformulated food: A review

Food reformulation, the process of redesigning processed food products to make them healthier, is considered a crucial step in the fight against noncommunicable diseases. The reasons for reformulating food vary, with a common focus on reducing the levels of harmful substances, such as fats, sugars, and salts. Although this topic is broad, this review aims to shed light on the current challenges faced in the reformulation of food and to explore different approaches that can be taken to overcome these challenges. The review highlights the perception of consumer risk, the reasons for reformulating food, and the challenges involved. The review also emphasizes the importance of fortifying artisanal food processing and modifying microbial fermentation in order to meet the nutrient requirements of people in developing countries. The literature suggests that while the traditional reductionist approach remains relevant and yields quicker results, the food matrix approach, which involves engineering food microstructure, is a more complex process that may take longer to implement in developing economies. The findings of the review indicate that food reformulation policies are more likely to succeed if the private sector collaborates with or responds to the government regulatory process, and further research is conducted to establish newly developed reformulation concepts from different countries. In conclusion, food reformulation holds great promise in reducing the burden of noncommunicable diseases and improving the health of people around the world.

Formation, migration, derivation, and generation mechanism of polycyclic aromatic hydrocarbons during frying

Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic and lipophilic, which can be found in frying system. This review summarized the formation, migration and derivation for PAHs, hypothesized the possible mechanism for PAHs generation during frying and presented the research prospects. Some factors like high oil consumption, high temperature, long time and oil rich in unsaturated fatty acids promoted the formation of PAHs and the presence of antioxidants inhibited the PAHs formation. The effect of proteins and carbohydrates in foods on the formation of PAHs is inconclusive. The formed PAHs were migrated into food and air. Moreover, some PAHs transformed into more toxic PAHs-derivatives during frying. The generation of PAHs may be related to low-barrier free radical-mediated reaction and the unsaturated hydrocarbons may be precursors of PAHs during frying. In future, the isotope tracer technology and on-line detection may be applied to discover intermediates and provide clues for studying PAHs generation mechanisms.

Fatty Acid Composition of Selected Street Foods Commonly Available in Malaysia

Despite growing evidence of increased saturated and trans fat contents in street foods, little is known about their fatty acid (FA) compositions. This study aimed to analyse the saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), polyunsaturated fatty acids (PUFAs), and trans fatty acids (TFAs) content of 70 selected and most commonly available street foods in Malaysia. The street foods were categorised into main meals, snacks, and desserts. TFAs were not detected in any of the street foods. Descriptively, all three categories mainly contained SFAs, followed by MUFAs, and PUFAs. However, the one-way ANOVA testing showed that the differences between each category were insignificant (p > 0.05), and each FA was not significantly different (p > 0.05) from one to another. Nearly half of the deep-fried street foods contained medium to high SFAs content (1.7 g/100 g–24.3 g/100 g), while the MUFAs were also high (32.0–44.4%). The Chi-square test of association showed that the type of preparation methods (low or high fat) used was significantly associated (p < 0.05) with the number of SFAs. These findings provide valuable information about fat composition in local street foods for the Malaysian Food Composition Database and highlight the urgency to improve nutritional composition.

Application of cellulose- and chitosan-based edible coatings for quality and safety of deep-fried foods

Excessive oil uptake and formation of carcinogens, such as acrylamide (AA), heterocyclic amines (HCAs), and polycyclic aromatic hydrocarbons (PAHs), during deep-frying are a potential threat for food quality and safety. Cellulose- and chitosan-based edible coatings have been widely applied to deep-fried foods for reduction of oil uptake because of their barrier property to limit oil ingress, and their apparent inhibition of AA formation. Cellulose- and chitosan-based edible coatings have low negative impacts on sensory attributes of fried foods and are low cost, nontoxic, and nonallergenic. They also show great potential for reducing HCAs and PAHs in fried foods. The incorporation of nanoparticles improves mechanical and barrier properties of cellulose and chitosan coatings, which may also contribute to reducing carcinogens derived from deep-frying. Considering the potential for positive health outcomes, cellulose- and chitosan-based edible coatings could be a valuable method for the food industry to improve the quality and safety of deep-fried foods.

Impact of starch-lipid complexes on oil absorption of starch and its mechanism

BACKGROUND

Worldwide, fried food has a huge demand and good development prospects. Low oil in foods is the standard that everyone is now pursuing for a healthy diet.

RESULTS

The oil absorption behavior of rice starch during frying was investigated in the presence or absence of fatty acids or fatty acid esters with different carbon chain lengths. The complex formed between starch and fatty acids or fatty acid esters was dependent on lipid chain length, which was confirmed by X-ray diffraction and complexing index. The formation of starch-lipid complexes could significantly reduce the oil absorption of starch, and the complexes with higher complexing index had lower oil absorption. The starch-palmitic acid complex showed the lowest oil absorption after frying, which was 14.06 g per 100 g lower than that of gelatinized starch. This was attributed to the ability of the palmitic acid to increase the density of starch crystalline polymorphs as well as their ability to complex with the amylose spiral cavity.

CONCLUSION

These results may be useful for development of healthier fried starch-based foods with reduced oil contents. © 2022 Society of Chemical Industry.

Utilization of Sunflower Oil-based Oleogel forDeep-Fried Coated Chicken Products

This study aimed to examine the effect of using oleogel as a frying medium on the quality of coated and deep-fried chicken products. Sunflower oil-based oleogels prepared with 0.5%, 1%, 1.5% and 2% carnauba wax were produced for deep frying of coated chicken products and were compared to sunflower and commercial frying oil based on palm oil. The increased carnauba wax concentration in the oleogel decreased the pH, oil, oil absorbance and TBARS value of coated chicken (p < 0.05). Samples deepfried with oleogels containing 1.5% and 2% carnauba wax had the lowest pH values. In addition, since the oil absorption during deep-frying was significantly reduced in these groups (1.5 and 2%), the fat contents of coated products were also lower (p < 0.05). The use of oleogel as a frying medium did not cause a significant change in the color values of the coated chicken products. However, the increased carnauba wax concentration in the oleogel increased the hardness of coated chicken (p < 0.05). As a result, sunflower oilbased oleogels with a carnauba wax content of 1.5% and higher which is healthier in terms of saturated fat content can be used as frying media and can be improved the quality of coated and deep-fried chicken products.

Batter Characteristics and Oil Penetration of Deep-Fried Breaded Fish Nuggets: Effect of Wheat Starch—Gluten Interaction

To understand the effect of the interaction between wheat starch ( $\mathrm{W}\mathrm{S}$ ) and wheat gluten ( $\mathrm{W}\mathrm{G}$ ) on batter characteristics and oil penetration of deep-fried breaded fish nuggets, batters were prepared using a $\mathrm{W}\mathrm{S}$ and $\mathrm{W}\mathrm{G}$ blend at the ratios of 15 : 1, 13 : 1, 11 : 1, 9 : 1, and 7 : 1 $\mathrm{w}/\mathrm{w}$ , respectively, and batter-breaded fish nuggets (BBFNs) were fried at 170°C for 40 s followed by 190°C for 30 s. Moisture adsorption isotherms of $\mathrm{W}\mathrm{S}$ and $\mathrm{W}\mathrm{G}$ , viscosity, rheological behavior, and calorimetric properties of the batters were measured, and pick-up of BBFNs, thermogravimetric properties of the crust, and oil transport were investigated. The moisture absorption capacity of $\mathrm{W}\mathrm{G}$ was higher than $\mathrm{W}\mathrm{S}$ at a low water activity (0.04–0.65), while the opposite trend was observed at a highwater activity (0.65–0.88). As the proportion of $\mathrm{W}\mathrm{S}$ decreased, the viscosity, $G”$ and tan δ of batter, pick-up of BBFNs, temperature and enthalpy change (ΔH) of protein denaturation and $\mathrm{W}\mathrm{S}$ gelatinization, and oil penetration of BBFNs during deep-fat frying, which are decreased until reaching a minimum value at the ratio of 11 : 1 $\mathrm{w}/\mathrm{w}$ , then increased ( $p<0.05$ ). However, G' of batter and thermogravimetry temperatures of crust exhibited the opposite trend. These results proved that the $\mathrm{W}\mathrm{S}$ – $\mathrm{W}\mathrm{G}$ interaction significantly affected the batter characteristics and oil penetration of BBFNs during deep-fat frying, which can be used to guide the manufacturing of low-fat fried BBFNs.

Monitoring the Changes in Heat Transfer and Water Evaporation of French Fries during Frying to Analyze Its Oil Uptake and Quality

The effect of frying temperature on heat transfer, water loss kinetic, oil uptake kinetic, and quality of French fries was evaluated. With increasing frying temperature, the core temperature of fries increased, and the Biot number and heat transfer coefficient (h) first decreased and then increased significantly (p < 0.05). The water loss rate (kw) and water effective diffusion of fries increased with the increasing frying temperature. The kw of fries fried at 150−190 °C were 0.2391, 0.2414, 0.3205, 0.3998, and 0.3931, respectively. The oil uptake rate (ko) first increased and then decreased with increasing frying temperature, and the ko of samples fried at 150−190 °C were 0.2691, 0.2564, 0.4764, 0.3387, and 0.2522, respectively. There were significant differences in the a*, L*, ΔE, and BI between fries with different temperatures (p < 0.05), while there was no significant difference in the b* (p > 0.05). The hardness and crispness of fries increased with increased frying temperature. The highest overall acceptability scores of fries were fried at 170 °C. Therefore, the changes in color, texture overall acceptability, and oil content were due to the Maillard reaction and the formation of porous structure, which was induced by h and water evaporation of fries when they changed.

Identifying key factors and strategies for reducing oil content in fried instant noodles

Fried instant noodles have become a popular instant food in recent years, favored by consumers for their unique flavor and taste. Unfortunately, the oil content of instant noodles is generally high, so the rise of fat-related diseases poses a major health issue. From the perspective of the cost of instant noodle manufacturers and the health of consumers, it is of great significance to reduce the oil content of instant noodles. The aim of this review article is to provide an overview of the main factors, such as raw materials and production processes, affecting oil content in instant noodles in order to suggest specific strategies to reduce the oil content in the end product. From the literature reviewed, adding acetylated potato starch/carboxymethyl cellulose, hydroxypropyl methylcellulose, or preharvest-dropped apple powder in the noodle formulation could be a better choice to reduce oil uptake by 5%-20%. Instant noodles with lower oil content can be produced using novel alternative frying technologies, including microwave and vacuum frying. The proper management of the production processes and the implementation of enhancement strategies may result in a reduction of oil content in the end product.

Inhibitory effect of chitosan coating on oil absorption in French fries based on starch structure and morphology stability

The effect of chitosan (CS) coating on oil absorption, water migration, starch structure and morphology in French fries was evaluated. The penetrated surface oil, structure oil, total oil content, and a* of coated fries decreased, while the water content, L*, b*, and hardness significantly (P < 0.05) increased compared to uncoated samples. 1 % CS-coated fries had the lowest oil content, which decreased by 43.0 % compared to uncoated samples. CS-coated fries had higher free water, and lower T₂ relaxation time, immobile and binding water than the control. CS coating reduced the pores on the fries' surface and the interaction between oil and the component of fries, which was observed by confocal laser scanning microscopy and scanning electron microscopy (SEM). As for starch morphology, the pores and cracks of starch granules in the coated samples reduced. As for the starch structure, the relative crystallinity, R_1047/1022 respectively increased by 47.2 % and 2.35 times, and ΔH of CS-coated fries increased from 0 to 2.09 J/g, indicating that the long-range crystalline structure, short-range ordered structure, and hydrogen bonds between the double helices in starch increased. Therefore, CS coating reduced oil penetration into fries by reducing water migration and increasing starch ordered structure and morphological integrity.

Pengaruh Tepung Beras Pragelatinisasi terhadap Penyerapan Minyak dan Sensori Kue Cucur

Cucur is a traditional food with oily appearance,which may affect the sensory acceptance. Thus, in this research we attempted to reduce its oil absorption by using pregelatinized rice flour as the ingredient for cucur dough. The type of rice and temperature of extrusion process affect the characteristics of pregelatinized rice flour and final products. Thus, the objective of this research was to determine the effect of using pregelatinized rice flour on the oil uptake and sensory of cucur. The type of rice used were IR64 and IR42, and the extrusion process temperatures were 130 and 150°C. The oil uptake by cucur made with pregelatinized rice flour was analyzed during deep frying and sensory analysis was done on the resulting cucur. The results showed that the type of rice, temperature of extrusion, and their interactions had a significant effect on the characteristics and sensory of cucur. A combination of IR42 and 150°C resulted in cucur with 35.97% moisture content, 19.32% fat content, 18.14% moisture loss, 18.14% oil uptake, while the overall sensory attribute was acceptable to the panelists. Use of pregelatinized rice flour resulted in decrease in the oil uptake and moisture loss. Cucur made with pregelatinized rice flour has desirable intensities of sensory attributes (appearance, flavor, texture, and mouthfeel), which result in the higher overall preferences score.

Migration and Distribution of PAH4 in Oil to French Fries Traced Using a Stable Isotope during Frying

Isotope-labeled four polycyclic aromatic hydrocarbons (PAH4-d12) were applied to study the migration and distribution of PAH4 in oil to French fries during frying. The results showed that the mobilities of PAH4-d12 showed a downtrend within 0-6 h and then an uptrend, and PAH4-d12 were mainly distributed in the crust of the French fries, especially five-ring PAHs-d12. The correlation analysis showed that PAH4-d12 migration was mainly caused by oil absorption of French fries. The low fluidity of the oil slowed down the PAH4-d12 migration, which was accelerated as the total polar component increased (higher than 15-20%). Additionally, higher frying temperature enhanced the crust ratio and porous structure of French fries, which explained the abundant five-ring PAHs-d12 distributed in the crust. This study provided references for optimizing the frying parameters: the exposure of PAH4 in French fries to humans can be reduced by controlling the oil quality and weakening the crust of the French fries.

Effects of Konjac Glucomannan on Oil Absorption and Safety Hazard Factor Formation of Fried Battered Fish Nuggets

The purpose of this study was to investigate the effects of konjac glucomannan (KGM) on oil absorption and the formation of safety hazard factors in fried battered fish nuggets by measuring advanced glycation end products (AGEs) and acrylamide contents. Other physicochemical properties were determined to explore the reason for oil absorption and formation of safety hazard factors. The acrylamide was found mainly in the crust. The addition of 0.8% KGM could significantly reduce the acrylamide content (p < 0.05). For the battered sample, the AGEs content was far lower than the unbattered. The addition of 0.8% KGM could significantly reduce the AGEs content in the inner layer (p < 0.05). The microstructure showed that the sample with 0.8% KGM had the most compact crust. The compact crust reduced oil and malondialdehyde contents. Combined with the other indicators, the inhibitory effect of 0.8% KGM on acrylamide was closely related with the decreased extent of oil oxidation and Maillard reaction in the samples with 0.8% KGM. The inhibitory effect of 0.8% KGM on AGEs might originate from its lower oil content.

Influence of Water, NaCl and Citric Acid Soaking Pre-Treatments on Acrylamide Content in French Fries Prepared in Domestic Conditions

The aim of this study was to investigate the influence of some pre-treatment applications toward acrylamide mitigation in potatoes fried in domestic conditions modeled after those found in Romania, by using a pan and a fryer. Before being fried in a pan, potato strips were treated in one of the following ways: soaked in cold water for 15, 60, and 120 min (a); soaked in hot water at different combinations of temperatures and durations (60, 70, 80 °C for 5, 10, 15 min) (b); soaked in a NaCl solution (c), and; in a citric acid solution (d) both solutions of 0.05% and 1% concentration for 30 min. For potatoes fried in a fryer, the (a) pre-treatment and soaking in water at 80 °C for 5, 10, and 15 min were applied. Untreated samples were used as a control. French fries were analyzed in terms of moisture and acrylamide content, color, and texture parameters. The pre-treatments applied reduced the acrylamide content in French fries by 4-97% when fried in the pan and by 25-47% when fried in the fryer. Acrylamide content of French fries was negatively correlated with L* parameter and moisture content and positively correlated with a* parameter. The pre-treatments applied can be used successfully by consumers to reduce acrylamide content.