Reduction Of Oil Uptake Research Articles

Barley flour addition decreases the oil uptake of wheat chips during frying

In the present study, wheat chips enriched with barley flour at different concentrations (5, 10, 15, 20, 25 and 30%) were produced and some physicochemical and textural properties, fatty acid composition and sensory quality of enriched chips were investigated. An increase in the values of some physicochemical parameters of wheat chips, namely hardness, dry matter, ash and some fatty acids levels, was observed with the increasing barley flour concentration in the formulation. Barley flour addition provided a significant oil uptake reduction as the oil content of the control sample was 27.23% while that of the enriched samples with 30% barley flour was 18.21%. Overall acceptability of wheat chips added with no barley flour samples was determined to be similar to compared to enriched ones. But addition of barley flour higher than 10% caused a decrease in sensory scores of the final products.

Study of oil uptake during deep-fat frying of Taro (Colocasia esculenta) chips

The effects of a water blanching pretreatment (BP, 85°C for 3 min), sample thickness (1 and 2 mm), oil temperature (180 and 200°C), and frying time (1 and 3 min) on the oil uptake (OU) behavior during the deep-fat frying of pre-dried (oven dried at 70°C for 20 min) taro (Colocasia esculenta) chips were investigated. Results demonstrated that using short frying times and high oil temperatures causes OU to decrease in both blanched and non-blanched samples (p < 0.01). In addition, higher product thicknesses were found to increase OU in non-blanched taro chips, while the opposite trend was found for the blanched slices (p < 0.01). BP also affected the OU, yielding lower fat contents (up to 80% of OU reduction) (p < 0.05), thus allowing the development of a fried taro product with reduced fat content (less than 30% fat content in dry basis).

A new technique to evaluate the effect of chitosan on properties of deep-fried Kurdish cheese nuggets by TOPSIS

Technique for Order Performance by Similarity to Ideal Solution (TOPSIS) method was used to comprehensively evaluate physicochemical properties of fried cheese nuggets so that chitosan (0, 0.5 and 1.5%) was added to batter formulation under different processing conditions namely frying temperature (150, 170 and 190 °C) and time (0–4 min). A non-destructive, image-based method was used to measured mechanical properties of fried, breaded cheese nuggets. The results of this study indicated that all the batters have shear-thinning behavior and the coating pickup was found to be directly proportional to batter viscosity. The highest reduction in oil uptake (22.7%) was observed in samples contain 1.5% chitosan. The deep fried cheese nuggets containing chitosan tended to be higher in hardness and maximum sound peak and lower in porosity in comparison to the control sample. The optimum conditions resulting in desirable physico-chemical properties and minimum oil uptake were cheese nuggets with chitosan content of 1.5%, fried at a temperature of 170 °C for 4 min.

A pore inactivation model for describing oil uptake of French fries during pre-frying

The reduction of oil uptake during deep-frying is a subject with societal relevance, given the trend towards lower-fat foods. Since research into oil absorption during frying is limited, we here report on developing better mechanistic understanding of this process. The oil uptake for different frying temperatures and fry dimensions was measured as a function of the water evaporation rate and water loss. A pore inactivation model was developed based on the hypothesis that the crust is a porous layer through which the exuding moisture vapour flow inhibits oil migration. Decreases in water evaporation rates will cause pores to inactivate, allowing oil to penetrate into the crust. The model provides good predictions to the experimental data. Since the model has two parameters, a purely statistical comparison with a simple linear fit having one parameter, does not show a significant benefit; however, the model better describes the overall trend of oil uptake.

Wheat gluten in extruded fish feed: effects on morphology and on physical and functional properties

This article focuses on understanding the role of vital wheat gluten on the structural parameters of extruded fish feed and its correlation to the physical and functional properties. Gluten–soy protein concentrate blends with five gluten concentrations (0–200 g kg-1) were produced. An abrupt reduction in oil uptake was observed with the 200 g gluten kg-1 blend. Inclusion of gluten from 100 to 200 g kg-1 resulted in unacceptable product properties. Sinking of feed pellets with 0 and 50 g gluten kg-1 was 100%, whereas only 36% of pellets with 200 g gluten kg-1 sank. We suspect that this is due to a relationship between morphological structure and oil impregnation during coating of feeds. The addition of gluten at 200 g kg-1 gave a smoother and non-porous outer surface. Pellets without gluten had a larger number of cells that were smaller than 200 µm (P <0.05) compared with pellets with 100 and 200 g gluten kg-1. More spherical cell shapes (P <0.01) and a compact structure were favoured in the presence of gluten. The closed porosity increased (P <0.05), whereas interconnectivity between pores decreased (P <0.01), with increasing gluten content from 0 to 200 g kg-1. The effects of the addition of gluten are probably related to the film-forming properties of gluten.

Effect of Ultrasound-Assisted Osmotic Dehydration as a Pretreatment on Deep Fat Frying of Potatoes

The objective of this study was to investigate the possibility of using ultrasound-assisted osmotic dehydration (UAOD) as a pretreatment prior to frying and to study its effects on the quality of fried potatoes. The quality parameters, moisture content, oil uptake, color, texture, and microstructure of fried potatoes, were chosen. Quality of fried potatoes treated with UAOD was also compared with the ones treated with osmotic dehydration (OD). Potato slabs (40 × 40 × 7 mm) were pretreated with different osmotic solutions (15 % sodium chloride and 15 % sodium chloride/50 % sucrose solutions) at different temperatures (25, 45, and 65 °C) with and without ultrasonic waves for different treatment times. The pretreatment conditions which are OD for 90 min and UAOD for 30 min using 15 % sodium chloride/50 % sucrose solution were applied prior to frying at 170 °C for 2, 4, and 6 min. UAOD reduced the oil content of fried potatoes by 12.5 % (db) as compared to untreated fried potatoes at the end of frying. There was no significant difference between OD and UAOD in reduction of oil uptake in fried potatoes. However, UAOD was found to have the advantage of improving the color of French fries. In addition, it shortened the pretreatment time of OD by about 67 %. Cell structure of fried potato was damaged in the presence of pretreatments of OD and UAOD.

Microstructural approach to understand oil absorption during vacuum and atmospheric frying

Crust microstructure plays a critical role in oil uptake of atmospheric fried food and seems to play an important role in vacuum fried products. The objective of this study was to understand the relationship between key microstructural parameters and oil absorption, after atmospheric and vacuum frying of different vegetable tissues. The effect of drainage and centrifugation in oil-uptake reduction was also analyzed. Key microstructural parameters were determined using gas adsorption at cryogenic temperatures, while oil location and surface roughness were studied using confocal laser scanning microscopy and area-scale fractal analysis, respectively. Overall, we found a linear relationship between porosity and final oil content in vacuum and atmospheric fried chips. However, this relationship could not be extended when analyzing the whole set of data, since oil absorption was significantly higher in atmospheric fried chips. Centrifugation allowed reducing oil-uptake up to 73% in atmospheric fried chips and up to 64% in vacuum fried ones.

Particle Size Fractionation of High-Amylose Rice (Goami 2) Flour as an Oil Barrier in a Batter-Coated Fried System

The particle size effects of high-amylose rice (Goami 2) flour on quality attributes of frying batters were characterized in terms of physicochemical, rheological, and oil-resisting properties. High-amylose rice flours were fractionated into four fractions (70, 198, 256, and 415 μm) of which morphology was also analyzed by scanning electron microscopy. Rice flour with smaller particle size exhibited a higher degree of starch gelatinization, giving rise to increased pasting parameters. When the rice flours were incorporated into frying batters, higher steady shear viscosity was observed in the batters with finer rice flour, which could be well characterized by the power law model. In addition, the dynamic viscoelastic properties of the batters were enhanced by the use of rice flour with smaller particle size, which also caused an increase in batter pickup. When subjected to deep fat frying, the batters with finer rice flour exhibited reduced moisture loss. Furthermore, the oil uptake was found to have a positive correlation with the particle size of rice flour (R2 = 0.88), even showing the reduction of oil uptake by 15%. It could be synergistically attributed to the formation of outer starch granular layers, high batter viscosity/pickup, and reduced moisture loss by finer rice flour.

Effect of hydrocolloids incorporation in casing of samosa on reduction of oil uptake

An experiment was conducted in Randomized Block Design (RBD) with the four types of hydrocolloids viz. HPMC, CMC, guar gum and xanthan gum. These hydrocolloids were added to wheat flour on dry basis at each 0.5, 1.0, and 1.5% levels in samosa. The prepared samosa was evaluated for various physico-chemical and sensory characteristics. The study revealed that xanthan gum at 1.5% level significantly reduced the oil content in samosa (8.56%) as compared to all other hydrocolloids and their concentration levels. Xanthan gum followed by CMC at 1.5% level (9.38%) was also statistically significant as compared to other hydrocolloids. Further it was observed that there was significant decrease in oil uptake with increase in level of all hydrocolloids. The samosa prepared with xanthan gum (1.5%) was also found superior with respect to sensory qualities compared to control.

Direct observation of the surface structure of French fries by UV–VIS confocal laser scanning microscopy

Abstract Observations of raw, fried and air-dried potato parenchyma samples were made with a UV–VIS confocal laser scanning microscope in reflective and fluorescence modes. Distinction between oil and cells was made possible by the addition of a fluorescent probe in the frying oil and the use of the natural fluorescence of cells. Observations were recorded at different depths and were treated to make volumetric reconstructions at different product scales. The results showed that after frying, the cellular structures were well conserved in terms of shape and size. Oil was shown to be mainly located in the first cell layer occupying around 50% of its volume. Oil remained in the cut cells emptied during the washing or the frying operation or in the damaged cells partially filled with starch. Cell detachment, because of starch swelling and dehydration, seemed to be the preferential connection between cell layers. The positive effect of air-drying toward oil uptake reduction could be the restriction of these connections.

EFFECT OF HYDROTHERMAL TREATMENT ON THE PHYSICOCHEMICAL, RHEOLOGICAL AND OIL‐RESISTANT PROPERTIES OF RICE FLOUR*

ABSTRACT Rice flour was thermomechanically modified by steam‐jet cooking and the physicochemical, rheological and oil‐resistant properties of the resulting product were characterized. Compared with native rice flour, the steam jet‐cooked rice flour exhibited significantly increased hydration properties. Its pasting properties were also characterized by cold initial viscosity, decreased setback and the lack of peak viscosity. The shear‐thinning behaviors of the steam jet‐cooked rice flour were satisfactorily fitted into the Carreau equation. In addition, dynamic viscoelastic measurements showed that the liquid‐like nature was more dominant over the solid‐like properties. When incorporated into frying batter formulations, the steam jet‐cooked rice flour increased the batter viscosity and pickup. The use of steam jet‐cooked rice flour also enabled fried batters to control the moisture loss effectively. Furthermore, the wheat flour replacement with 20% steam jet‐cooked rice flour in batters led to dramatic reduction of oil uptake by around 40%. PRACTICAL APPLICATIONSThis study introduces a hydrothermal treatment (steam‐jet cooking) as a new technique to impart better functional properties to rice flour. Specially, the steam jet‐cooked rice flour exhibited oil‐resisting properties when incorporated into frying batters, consequently producing fried foods with reduced content of oil and calorie.

Effects of Carrageenan, oil temperature and time of frying on oil uptake of fried potato products.

The demand for low fat snacks is increasing. There are different methods to produce low fat fried products. One of these methods is coating. In this study effect of Carrageenan, oil temperature and frying time, on oil uptake of fried products (chips and strips) has been evaluated. Samples were deep fried in frying oil (Palm olein) at 160, 175 and 190 oC. In order to evaluate the effect of frying time on oil uptake, potato strips coated with 1% Carrageenan were fried for 1 to 10 minute, then oil uptake has been measured. Results showed that Carrageenan as a hydrocolloid coating, reduced oil uptake in fried potato products compare with control samples. Coating potato slices with 1% Carrageenan led to significantly reduction in oil uptake (p<0.05) which was 37.23, 41.10 and 43.67(%) at 160, 175 and 190 oC respectively, whereas this amount for control samples was 43.27, 47.2 and 49.53(%) respectively. For potato strips coated with 1% Carrageenan, oil uptake at above oil temperature was 12.17, 14.43, and 18.63 (%), whereas this amount for control samples was 17.60, 20.83 and 23.13(%) respectively. Increasing oil temperature in a specific frying time led to significantly increase in oil uptake (p<0.05). Frying samples for 1 to 10 min, led to significantly increase in oil uptake (p<0.05). Key words: Potato chips, Carrageenan, Oil uptake

A Different Perspective to Study the Effect of Freeze, Air, and Osmotic Drying on Oil Absorption during Potato Frying

The objective of this article is to assess the effect of different dehydration pretreatments on oil absorption and illustrate how the different ways results can be reported may even drive to opposite conclusions. To do so, potato cylinders were blanched in hot water and dried until a moisture content of 62% (w.b.) by either freeze-drying, air drying, and osmotic drying with a sucrose solution or osmotic drying with a NaCl solution. Control (blanched) and dried potatoes were deep-fat fried at 170 degrees C for time periods between 1 and 5 min. Water removal and total oil uptake were determined and 2 oil fractions were distinguished: superficial oil and penetrated oil. Compared to the control, freeze dried samples increased oil uptake in 15.4% (d.b.) whereas air-dried samples reduced it in 11.2% (d.b.). Similarly, osmotic dehydrated samples showed a high reduction in oil uptake compared to the control (up to 27%[d.b.] when using a sucrose solution). However, this high decrease in oil absorption was attributed to the increase in solids content occurring during the osmotic dehydration process rather than a reduction in the amount of oil taken up. In fact, when the amount of oil absorbed per cylinder was determined, it was verified that oil uptake of osmotically dehydrated samples was even higher than the control, as opposed to what has been previously reported in the literature. These results highlight the importance of selecting an adequate basis to carry out comparisons properly.

Comparison of the deep frying process in coated and uncoated dough systems

The effect of an edible methylcellulose coating to reduce oil uptake during frying was analyzed on a dough system. The oil uptake reduction was 30% for coated dough discs compared to uncoated ones; the coating neither modified the water content of the samples nor the quality attributes of the fried dough such as color and texture. A mathematical model was developed including simultaneous heat and water vapor transfer at the different stages of the frying process and the cooling at environmental conditions after the product was removed from the fryer. It allowed to simulate satisfactorily the experimental data of temperature profiles, water losses and the thickness of the dehydrated zone ( d T) as a function of frying time. Post-frying oil uptake was correlated with d T considering microstructural changes during frying time, analyzed by SEM (scanning electron microscopy). The coating reduced oil uptake, modifying the wetting properties related to the interfacial tension and also becoming a mechanical barrier to lipids.

Production of Protein-Coated Low-Fat Potato Chips

The purpose of this study was to prepare protein-coated potato chips and evaluate type of proteins and storage time on the quality of final product. Potato slices were prepared, blanched, immersed in solutions of sodium caseinate, whey proteins concentrate (WPC), or egg white and deep-fried in a mixture of corn oil and commercial hydrogenated oil. Chips were packed and stored for different times. The results showed that sodium bisulphite in blanching solution improved binding of proteins to potato slices. Protein coating resulted in significantly lower oil uptake of potato chips. Coating potato chips with sodium caseinate, WPC and egg white proteins resulted in 14, 5 and 12% reduction in oil uptake, respectively. Water retention and protein content significantly increased in protein-coated chips. Peroxide values increased with storage time in all samples. Protein-coated chips had a decrease in peroxide value between 30 to 50%. Sensory evaluation of chips showed that at all storage time intervals, flavour of sodium caseinate-coated chips were more acceptable than non-coated, WPC or egg white protein-coated chips.

Edible coatings from cellulose derivatives to reduce oil uptake in fried products

Methylcellulose (MC) and hydroxypropylmethylcellulose (HPMC) were used in coating formulations to reduce oil uptake in deep-fat frying potato strips and dough discs. MC coatings were more effective in reducing oil uptake than HPMC ones. The effect of plasticizer addition (sorbitol) was also evaluated. The best formulations were 1% MC and 0.5% sorbitol for fried potatoes and 1% MC and 0.75% sorbitol for dough discs. For these formulations, oil uptake reduction was 40.6 and 35.2% for potato strips and dough discs compared to the uncoated samples; the increase in water content was 6.3 and 25.7%, respectively. Non-significant differences in texture of coated and uncoated samples were observed. Although instrumental color differences were detected, all samples were accepted by the non-trained panel.

Reduction of oil uptake in deep fried tortilla chips Reducción de la absorción de aceite en la fritura de tiras de maíz

The reduction of oil uptake in fried tortilla chips was attempted with baking and carboxymethyl cellulose (CMC) addition. The effects of CMC type and concentration, frying time, and prefrying treatment on oil uptake and moisture content were studied. Chips were prepared using corn masa flour. Results showed that the addition of CMC reduced the oil uptake significantly for all samples. The reduction in oil uptake ranged from 5-40% according to the CMC type and concentration. The most effective CMC type was high viscosity, which caused a 40% reduction in oil content for 30 s frying time of baked samples. The addition of CMC also reduced the initial moisture content of raw chips. The highest moisture content reduction was for samples prepared with low-viscosity CMC. Frying time was an important factor on oil uptake and moisture content. When frying time increased, oil content increased while moisture content decreased.

Screening of hydrocolloids for reduction in oil uptake of a model deep fat fried product

Reduction of oil content in deep fat fried foods would be welcome by both the food manufacturers and the consumers. Among the many approaches that have been evaluated for this purpose, use of hydrocolloid additives is believed to be most promising. Work in this area is restricted mostly to cellulose derivatives. The mechanism of action of these derivatives is attributed to formation of an oil resistant barrier film, an alteration in surface hydrophobicity of the product being fried, and the thermal gelation. However, most hydrocolloids would alter the surface hydrophobicity, and many of them have the ability to form films. Furthermore, the presence of other food constituents can alter all these properties. Hence, hydrocolloids at 0.25— 2.00 % (on the basis of chickpea flour) were screened for their ability to reduce oil uptake in sev, a model deep fat fried product prepared from chickpea flour. Results obtained indicate that the ability to reduce oil uptake in this product decreases in the following order: gum arabic > carrageenan > gum karaya > guar gum > carboxymethylcellulose > hydroxypropylmethyl cellulose. Hydrocolloids such as xanthan, gum ghatti, gum tragacanth, and locust bean gum were found to be ineffective (<10 % reduction in the oil content) for this purpose. Screening von Hydrokolloiden zur Reduktion der Olaufnahme eines modellhaft frittierten Produkts.Die Reduktion des Olgehalts in frittierten Nahrungsmitteln wurde sowohl von den Nahrungsmittelherstellern als auch den Konsumenten begrust werden. Unter den vielen Ansatzen, die zu diesem Zweck bereits ausgewertet wurden, gilt der Einsatz von hydrokolloiden Zusatzen als am vielversprechendsten. Die Arbeit in diesem Gebiet ist vor allem auf Zellulosederivate beschrankt. Die Aktionsmechanismen dieser Derivate werden der Bildung eines olresistenten Films, der Anderung der Oberflachenhydrophobizitat des frittierten Produkts und der thermischen Gelatinisierung zugeschrieben. Allerdings wurden die meisten Hydrokolloide die Oberflachenhydrophobizitat verandern, und viele von ihnen haben die Fahigkeit, einen Film auszubilden. Daruber hinaus kann das Vorhandensein anderer Nahrungsmittelbestandteile diese Eigenschaften andern. Daher wurden Hydrokolloide in einer Konzentration von 0,25— 2,00 % (auf der Basis von Kichererbsenmehl) im Hinblick auf ihre Fahigkeit, die Olaufnahme in Sev, einem modellhaft frittierten Produkt, zu reduzieren, gescreent. Die gewonnenen Ergebnisse zeigen, das die Fahigkeit, die Olaufnahme bei diesem Produkt zu reduzieren, in der folgenden Reihenfolge abnimmt: Gummi arabicum > Carrageenan > Gummi karya > Guar Gummi > Carboxymethylzellulose > Hydroxypropylmethylzellulose. Hydrokolloide, wie Xanthan, Gummi ghatti, Gummi tragacanth und Johannisbrot-Gummi, stellten sich fur diesen Zweck als nutzlos heraus (<10 % Reduktion des Olgehalts).