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Summary: The quality of processed products can be adversely affected by uncontrollable batches of mangoes, which exhibit heterogeneous characteristics. This study aimed to establish predictive models for sugar and organic acid contents (dependent variables) in processed products using the initial compositions of fresh mangoes. Three mango cultivars (cv. 'Kent', cv. 'Keo Romeat', and cv. 'Keo Chen') were classified as low‐density and high‐density groups. Each group of mangoes at the green‐mature, mid‐ripe, and ripe stages was processed into pasteurised purees, dried slices, and mango chips. Prediction models were established using a mix of simple linear regression (SLR) based on the initial content and Analysis of Variance (ANOVA) to identify the impact of qualitative variables (ripening stage, cultivar‐density, and processing technique). In processed mangoes, 13% sucrose content was estimated to accumulate with the three qualitative variables, whereas glucose and fructose contents decreased from their initial levels by 10% and 7%, respectively. Processing techniques can predict the ratio of sugars/acids (S/A) in processed products, regardless of the ripening stage or cultivar‐density. Similar to S/A, citric acid and malic acid contents in mango products were significantly increased by processing techniques. The initial content and processes were insufficient to predict the final contents of the same parameters in processed mangoes; therefore, some models need to include the effects of ripening stage and cultivar‐density to improve the prediction. These relevant explanatory variables contributed significantly to the development of the models, resulting the accuracy of predictive models with normalised root mean square errors (NRMSEs) lower than 10%, except for malic acid (14.04%). In conclusion, it is feasible to estimate the sugar and acidity levels in processed mangoes, offering promising possibilities for ensuring consistent quality of mango‐based products. [ABSTRACT FROM AUTHOR]

The effect of vacuum pressure mode has not been studied depth yet. Effect of vacuum pressure on the quality of vacuum‐fried banana slices was studies in this work. Three vacuum frying processes were conducted and tested. Classically, two constant vacuum pressures 80 (CVF‐80) and 180 mmHg (CVF‐180) were applied in the frying process at 90°C. One novel frying method with gradient vacuum pressure (GVF) changed from 760 to 80 mmHg was conducted and adapted. The frying temperature was kept at 90°C. The frying processes were monitoring by moisture contents and 4% was generally accepted as moisture content of final product. Meanwhile, the frying times of CVF‐80, CVF‐180 and GVF were 50, 80 and 60 min, whereas the brightness values (L*) were corresponded to 71.07, 71.36, 67.25, respectively. The GVF samples were brightest with lowest hardness value (30.8 N) and the CVF‐180 was darkest with highest hardness value (36.87 N). The microstructure analysis showed that the GVF increase in both size and number of pores in comparison with CVF. Additionally, based on the paired comparison sensorial test the GVF fried banana slices were crisper than CVF samples. Our results revealed that the GVF method improves the quality of vacuum‐fried banana slices, thus it can be good alternative method for production of banana snack. [ABSTRACT FROM AUTHOR]

Deep fat fried food products have been considered as a vital dietary contributor to certain chronic diseases, including the risk of atherosclerosis, cancer and hypertension. Hence, many food industries are focusing on low fat fried products to attract consumers. In general, oil is absorbed during deep fat frying, and this century old process is used for preparing various kinds of fried food products such as potato chips, banana chips, savory snacks, etc. Vacuum frying, electric field frying and two-stage frying technologies have been developed as an alternatives to traditional frying. These two technologies are suitable for most fried products; however, they may not be suitable for sugar based fruits as they can lead to the formation of browning reactions, which are generally considered unacceptable. This review aims to cover recent work done in the area of vacuum frying and two-stage frying, including the role of pre-treatment and post-treatment novel methods. Additionally, emphasis has been given on recent innovations to improve the quality of vacuum and two-stage frying, particularly concerning the reduction of oil uptake in fried food products. [ABSTRACT FROM AUTHOR]

Banana chip processing in Lampung province uses two different frying methods, namely conventional frying and vacuum frying. The objective of this study was to compare the number of impact emissions generated from the banana chip production process in banana chip agro-industries in Lampung. This research was conducted based on the Life Cycle Assessment (LCA) method to assess the environmental impact emissions from the banana chip industry in Lampung, focusing on the impacts of Global Warming Potential (GWP), Acidification Potential (AP) and Eutrophication Potential (EP) with a function unit of 250 g/pack. Analysis using SimaPro 9.4.2 software. Analysis using the CML-IA Baseline method shows that the banana chip industry has a significant environmental impact with the largest impact by the industry, where the conventional frying method produces a GWP impact of 1.16 kg CO2 eq/package, EP 2.08E-2 kg PO4 eq/package and AP 3.6E-3 kg SO2 eq/package, while in the vacuum frying method, the GWP is 6.3E-1 kg CO2 eq/package, AP 2.3E-3 kg SO2 eq/package and EP 6,1E-3 kg PO4 eq/package. The calculated normalization data shows that the total impact of producing banana chips per package in conventional frying is 1.9E-12 person equivalent/package with the frying stage contributing 85.45% and in vacuum frying is 6.7E-13 person equivalent/package with the frying stage contributing 77.70%. The resulting emission impact value shows that the emission impact of conventional frying is higher than the emission impact of vacuum frying. However, an economic and social assessment of both frying methods needs to be done to see the sustainability index of both.

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agroindustrial Technology / Jurnal Teknologi Industri Pertanian is the property of IPB University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract The ubiquitous presence of fried foods in our diet necessitates the upgradation of techniques to override the ill effects of conventional frying. Vacuum frying, employing frying at low pressure and temperature has recently attracted research due to its excellent food frying capabilities with minimal damage to nutritional as well as sensorial quality. The objective of this review paper is to highlight the basics of vacuum frying technology, provide information about quality of vacuum fried products, parameters affecting the frying process, and interventions to improve the products quality. Prospects of vacuum frying technology to develop products with lower oil content using certain pre-treatments to foods such as partial drying, freezing, hydrocolloids etc. are included. With proper deployment and overcoming of the research gaps, vacuum frying technology can be used effectively as a food processing technique both in small as well as large-scale production industries.

Vacuum-fried products were prepared with macadamia kernels as raw material. Single factor experiment and response surface Box-Behnken test were used to optimize the vacuum frying process of macadamia kernels. Oil content, acid value, peroxidation value, color difference and sensory quality of vacuum-fried kernel were determined by comparing with raw kernel. The results showed that the effects of freezing temperature, vacuum frying temperature, vacuum frying time and vacuum degree on taste and flavor quality of macadamia kernels were significantly different (P

To improve the production process of meat products in the industrialization of Sichuan cuisine, this study was conducted to investigate the effects of different vacuum frying temperature, frying time and slice thickness on moisture content, color, texture characteristics and sensory scores of pork belly slices, and to optimize the vacuum frying process conditions of pork belly slices using response surface combined with principal component analysis based on single-factor experiments and correlation analysis. The results showed that moisture content, a* value, b* value, hardness, and chewiness were more strongly correlated with 3 factors, namely, frying temperature, frying time, and slice thickness. The cumulative contribution rate of the first two principal components extracted in the principal component analysis was 82.822%, which could evaluate the quality of vacuum-fried pork belly slices to a certain extent. An optimal vacuum frying process for pork belly slices was achieved, where frying temperature 100 ℃, frying time 3 min, and slice thickness 3 mm. In this case, the standardized comprehensive score of pork belly slices was 0.931, and a standard deviation from the predicted value was 0.5%, indicating that the model could better predict the standardized comprehensive score of vacuum-fried pork belly slices. This process would provide a feasible method and a certain theoretical reference for the production of meat products in the industrialization of Sichuan cuisine.

The quality changes of ready-to-eat vacuum-fried hairtail with different packaging during 60 days storage at 25 ℃ were studied in this study to choose the optimal packaging material. The changes in water content, water activity, pH, peroxide value (POV), thiobarbituric acid value (TBARS), and acid value (AV) of vacuum-fried hairtail during storage were evaluated using plastic sealed cans packaging and nitrogen-filled aluminum foil bags packaging, respectively. Also, the taste substances of instant vacuum-fried hairtail at the end of storage were determined. The results showed that the water content and water activity increased first and then remained unchanged. After 60 days of storage, the water content and water activity of hairtail sealed with plastic cans were 1.23 times and 1.19 times more than those sealed with aluminum foil bags. The relevant parameters of lipid oxidation (POV, TBARS, and AV) of vacuum-fried hairtail showed a time-dependent upward trend during storage. The POV, TBARS, and AV values of hairtail sealed with plastic cans were 1.84, 1.43, and 1.13 times than those of hairtail with aluminum foil bag after 60 days storage. These results indicated that nitrogen-filled aluminum foil bag packaging could effectively block moisture in the bag, slow down the lipid oxidation deterioration of the product. The taste substances of instant vacuum-fried hairtail at the end of storage were determined by electronic tongue, the results showed that nitrogen-filled packaging of aluminum foil bag could slow down the generation of bitter substances, superior to sealed cans packaging in terms of salty taste, delicious taste, and rich flavor. In conclusion, the nitrogen-filled aluminum foil bag would be the optimal material for the packaging and storage of instant vacuum-fried hairtail.

Vacuum frying (VF) is a selective technique for producing high-quality fried food that is mostly used on vegetables, fruits, and potato chips. It is rarely applied to the production of aquatic (especially fish) products. The purpose of this study is to explore whether VF technology can be applied to the preparation of dried silver herring products and to obtain the optimal VF conditions. The response surface methodology (RSM) was used to examine the factors affecting the quality of silver herring (Spratelloides gracilis) products after VF, namely temperature (75, 90, and 105 °C), duration (25, 35, and 45 min), and concentration (0, 15, and 30%) of maltose solution used to immerse the samples during pre-processing. The results indicated that VF temperatures had significant impacts on water activity (Aw), moisture content, yield, oil content, lightness (L* value), and colour difference (ÄE). The higher the VF temperature, the lower the Aw, moisture content, yield, and oil content of the product, but the higher the L* value and ΔE. Next, a longer VF duration resulted in higher oil content of the product. Maltose concentration was significantly and positively correlated with the yield and fracturability of the product. RSM analysis indicated that the optimal combination of processing conditions was a VF temperature of 105 °C, VF duration of 25 min, and maltose concentration of 27%. Under these VF conditions, the silver herring products had a moisture content of 3.91%, Aw of 0.198, oil content of 21.69%, L* value of 28.19, ΔE of 27.31, and fracturability of 359 g/s. In summary, vacuum frying technology is suitable for the preparation of dried silver herring products, and this study can provide the optimal processing conditions for seafood processors to obtain better quality. [ABSTRACT FROM AUTHOR]

Deep-frying is a traditional cooking method in China, endowing the product with unique crispy characteristic but also greasiness. High-calorie fried foods can create health risks. Many attempts have been made by researchers to reduce the absorption of oil during the frying process while ensuring the good quality of deep-fried products. This paper reviews the oil-absorbing behavior of deep-fried starch-based products during the frying process and describes several methods to regulate the oil content of deep-fried products. Adding functional ingredients (proteins or starches and a combination of hydrocolloids with the main ingredients of the product) is in line with the current trend of nutritious and low-fat foods. Coating technology, which utilizes natural macromolecules as an oil barrier, has promising applications in the production of low-fat fried foods. In addition, new frying technologies such as vacuum frying, air frying and spray frying are becoming increasingly mature, and can gradually replace traditional frying for the production of low-fat fried products according to the needs of industrial production. All regulatory measures described in this paper can reducing the oil content of different fried products to different degrees, which will provide a scientific and theoretical basis for selecting a suitable measure for oil reduction in different fried starch-based products based on their oil absorption mechanisms, and provide a theoretical reference for the development of low-fat fried products.

This study investigated the possibility of using asparagus (Asparagus officinalis L.) to produce healthy snacks using vacuum frying. The tip and middle part of asparagus Grade C were soaked in 0.1% Calcium chloride solution and blanched at 95–98°C for 45 s, immediately soaked in water at 30°C for 2 min and packed in the bags to freeze at −18°C before vacuum frying. The samples were fried at 80°C and 986 mbar for 38, 40 and 42 min, and then excess oil in the sample was removed by a centrifuge before being measured properties. The effects of different frying times on the physicochemical and sensory characteristics of the vacuum-fried asparagus were analysed. A scanning electron microscope was used to study the structure of the vacuum-fried product. The result reveals that increasing frying time decreased moisture content, aw, yield, greenness value and crispiness of vacuumed snacks but increased lightness and yellowness values. SEM showed that vacuumed snacks with increasing frying time resulted in a gradual increase in the size of pores inside the product. When the frying time increased to 42 min, collapsed pores were observed, indicating a breakdown structure. A sensory evaluation of seasonings on vacuum-fried asparagus found that fried asparagus with truffle seasoning had the highest preference levels for all sensory attributes. The truffle seasoned fried asparagus at 80°C under vacuum at a pressure of 986 mbar for 40 min contained protein and fibre content of 14.21 and 15.55%, respectively, vitamin A and beta-carotene of 2.717 μg and 16.30 μg, respectively, and calcium and iron of 182.68 mg and 2.88 mg, respectively. Microorganisms found are under the regulated amount according to the Notification of the Ministry of Public Health. This study demonstrates that asparagus Grade C can be used to produce healthy and acceptable fried snacks.

The purpose of this study was to optimize product yield and quality of the sweet potato chip manufacturing process in a pilot-scale industrial fryer using vacuum frying (VF) technology, response surface methodology (RSM), and artificial neural network (ANN) model. The variables, osmotic dehydration (OD) concentration, OD temperature, and VF temperature were designed to optimize the yield, oil content, and browning index (BI) of vacuum-fried sweet potato chips. Yield, oil content, and BI achieved optimal conditions for 52.46%, 10.65%, and 61.14 in RSM, and 53.52%, 11.58%, and 60.40 in ANN, respectively. Based on the statistical evaluation performance, the ANN model had a higher predictive performance than the RSM model. These findings highlight the high-quality pilot-scale manufacturing process along with a better statistical approach. Moreover, the optimized process can be used for the commercial production of vacuum-fried sweet potato chips. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the physicochemical characteristics and volatile flavor of fried tilapia skins under three frying methods. Conventional deep-fat frying usually increases the oil content of the fried fish skin and leads to lipid oxidation, which reduces the product quality. Alternative frying methods, such as air frying for 6 and 12 min under 180 °C (AF6, and AF12) and vacuum frying at 0.085 MPa for 8 and 24 min under 120 °C (VF8, and VF24) were compared to conventional frying for 2 and 8 min under 180 °C (CF2, and CF8) for tilapia skin. Physical properties of fried skin, such as the moisture content, water activity, L* values and breaking force decreased under all frying methods, while the lipid oxidation and a*, b* values increased with the increase in frying time. In general, VF offered higher hardness of product compared to AF which had a lower breaking force. Especially AF12 and CF8 had the lowest breaking force, which indicated higher crispness. For the oil quality inside the product, AF and VF reduced conjugated dienes formation and retarded oxidation compared to CF. The results of the flavor compositions of fish skin measured using gas chromatography mass spectrometry (GC/MS) with solid phase microextraction (SPME) showed that CF obtained higher unpleasant oily odor (nonanal, 2,4-decadienal, etc.), while AF presented greater grilling flavor (pyrazine derivatives). Because fish skin fried by AF only relied on hot air, Maillard reaction derived compounds, such as methylpyrazine, 2,5-dimethylpyrazine, and benzaldehyde were the leading flavors. This made the aroma profiles of AF very different from VF and CF. Among all the approaches, AF and VF developed lower oil content, mild fat oxidation and better flavor attributes, which proves their practical applications for frying tilapia fish skin. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background. Osmotic treatment is necessary to reduce the oil on the vacuum-fried product. However, the nutrition of the treated sample is also affected, especially bioactive compounds. Materials and methods. The Box-Behnken model was applied to evaluate the change in bioactive compounds of vacuum-fried shallots during osmotic dehydration in the pilot-scale plan. Three factors of osmotic treatment were examined, namely the concentration of maltodextrin (30–50%), concentration of citric acid (0.1–0.2%), and dehydration time (15–45 minutes). The frying conditions were constantly set at a temperature of 120 ±1o C with a vacuum of 680 mmHg for 8 minutes. Results. The results showed that all factors significantly affected the content of phenolics and flavonoids in the sample. The optimal condition of the dehydration process was found to be 38.9% maltodextrin and 0.17% citric acid in the soaking medium, and the soaking time was 31.9 minutes. The sample’s total phenolic and flavonoid content in optimal conditions were 12.44 mgGAE/g and 1841.73 µgQE/g, respectively. Conclusion. The quality of vacuum-fried shallots was greatly affected by osmotic dehydration conditions. It was also found that under optimal conditions the biological compounds of the product are still maintained at a high level. Further studies on the techno-economic value of the product for commercialization should be considered. [ABSTRACT FROM AUTHOR]

The microwave assisted vacuum frying (MWVF) of Durian cv. Monthong was performed to investigate the effect of microwave power levels (400,480, and 560 W) and ripening stages 1 Day, 2 Days, 3 Days, and 4 Days after harvesting) on the kinetics of the durian chips. The physio-chemical properties, the specific energy consumption (SEC) and product acceptability using sensory evaluation were also determined at 110 °C and absolute pressure of 8 kPa. At the higher microwave power, the frying time was reduced leading to a lower SEC. Moreover, it also resulted in decreasing oil absorption, decreasing shrinkage, and increasing porosity. In addition, more ripeness in durians led to longer frying time, increased oil uptake, but also produced a more porous structure and higher crispiness. Furthermore, using the 7-point hedonic scale test, the sensory evaluation revealed that the chips from the more ripened durian had the higher overall acceptability score. [ABSTRACT FROM AUTHOR]

Fried oyster is a popular aquatic food product in East Asia, but nutrient loss during thermal processing become a significant concern. The goal of this research was to examine the impact of distinct frying techniques, including deep frying (DF), air frying (AF), and vacuum frying (VF), on the nutritional, textural and flavor characteristics of oysters. The VF method demonstrated superior retention of beneficial properties and flavor, and reduced protein and lipid oxidation compared to the DF and AF methods. Furthermore, proteomic analysis of oysters was attempted to explain the molecular mechanisms governing the influence of key differential proteins. 20 major differential proteins, including actin-2 protein, tryptophan 2,3-dioxygenase and 1-alph, involved in oyster protein oxidation were identified, annotated and analyzed to elucidate their influence mechanisms. This research provides a deeper understanding of intricate interactions between frying techniques and oyster biochemistry, which offers valuable implications for enhancing food quality in seafood industry [Display omitted] • Different frying methods were used to analyze the quality of oysters. • The compositional variation of fried oyster was determined. • The mechanism of quality change was analyzed by proteomics. [ABSTRACT FROM AUTHOR]

Potato fries, a relatively an untapped food matrix for fortification, was fortified with iron using vacuum impregnation technique and impact of this fortification on quality attributes (structure, color, texture, flavor, acrylamide, sensory characteristics) of the product was assessed. Further, to reduce the dietary restraints of consumers for fried fries, fat reduction was achieved using vacuum frying. Ferrous ammonium sulphate hexahydrate was used as a fortificant to yield 3.15 mg iron from 30 g fries (RACC for snacks- Recommended Amount Customarily Consumed). Effect of iron fortificant level, blanching, vacuum and restoration time (independent variable) were evaluated on responses (iron impregnation level and firmness) of fries using box-behnken design of response surface methodology. Results showed that blanching time was the most significant variable affecting iron impregnation followed by iron concentration and vacuum time. Ferrous ammonium sulphate hexahydrate was found to be the most appropriate fortificant since reflecting the least colour and sensory changes in fries. A fortified raw potato fries when fried under vacuum, provided better retention of colour and reduced fat absorption (by 17.72%) with comparable crispiness (0.37 kg/sec vs 0.35 kg/sec), firmness (0.39 kg/sec vs 0.38 kg/sec), color (ΔE = 1.39) and sensory score (7.9 vs 8.1 on 9-point scale) with control fries. [ABSTRACT FROM AUTHOR]

Copyright of Jurnal Ilmiah Pangan Halal is the property of Universitas Djuanda and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Effects of pretreatments (blanching, air-drying, osmotic dehydration and freezing) and process parameters: frying temperature (100, 110 and 120°C) and frying time: (180, 300 and 420 s) at constant vacuum pressure of 70 mbar on some quality characteristics of vacuum fried onion chips (oil uptake, shrinkage, breaking force, and total color difference) were studied. The results showed that frying temperature and frying time at all pretreatments had a significant effect (p ≤ 0.05) on oil uptake and shrinkage, as well as total color difference and breaking force of vacuum fried onion chips. The results demonstrated that the oil uptake, shrinkage and total color difference of the fried onion chips increased, while breaking force decreased with increasing frying temperature and time. The results showed that the different pretreatments before vacuum frying influenced significantly (p ≤ 0.05) the quality characteristics of vacuum fried onion chips. At the same frying temperatures and frying times, the lowest oil uptakes were observed in osmotic dehydrated samples, followed by air-dried and then blanched samples. Freezing pretreated onion samples show the highest o oil uptake (p ≤ 0.05) than other pretreatments. Freezing pretreatment resulted in minimum shrinkage, compared to other pretreatments (p ≤ 0.05) followed by osmotic dehydrated samples. Shrinkage in air drying and blanching pre-treated samples did not differ significantly. Osmotic dehydration pretreated onion samples show less breaking force (p ≤ 0.05) than other pretreatments followed by air-dried pretreated onion samples while blanching and freezing pretreatment resulted in minimum crispiness. At the same temperatures and frying times, the lowest levels of total color difference were observed in blanched samples, followed by osmotic dehydrated and then the air-dried samples. Freezing pretreated onion samples show the highest levels of total color difference (p ≤ 0.05) than other pretreatments.

The reduction of oil uptake in vacuum-fried Pleurotus eryngii chips by ultrasound assisted pretreatment was investigated regarding the pore structure changes. Pore structure of P. eryngii chips with four pretreatments, such as blanching, blanching + osmosis, blanching + ultrasound and blanching + ultrasound assisted osmosis was determined by mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM). In addition, the quality parameters of vacuum-fried P. eryngii chips such as hardness, rehydration ratio, reducing sugar, protein and oil content were also measured. The results showed that the oil absorption of vacuum fried P. eryngii chips was affected by the porous structure. The oil content of vacuum fried P. eryngii chips was significantly and positively correlated with the pores with diameters above 50, 5–50, and 0.5–5 μm in the samples both before and after vacuum frying, while negatively correlated with the pores with diameters below 0.5 μm. Ultrasound pretreatment changed the microporous structure of P. eryngii chips, effectively hindering the oil absorption of samples. In particular, ultrasound assisted osmosis pretreatment induced the formation of more micropores. It was concluded that blanching + ultrasound assisted osmosis pretreatment is a promising method to reduce oil absorption and improve the quality of vacuum fried foods.

Vacuum frying (VF) is a selective technique for producing high-quality fried food that is mostly used on vegetables, fruits, and potato chips. It is rarely applied to the production of aquatic (especially fish) products. The purpose of this study is to explore whether VF technology can be applied to the preparation of dried silver herring products and to obtain the optimal VF conditions. The response surface methodology (RSM) was used to examine the factors affecting the quality of silver herring (Spratelloides gracilis) products after VF, namely temperature (75, 90, and 105 °C), duration (25, 35, and 45 min), and concentration (0, 15, and 30%) of maltose solution used to immerse the samples during pre-processing. The results indicated that VF temperatures had significant impacts on water activity (Aw), moisture content, yield, oil content, lightness (L* value), and colour difference (ÄE). The higher the VF temperature, the lower the Aw, moisture content, yield, and oil content of the product, but the higher the L* value and ΔE. Next, a longer VF duration resulted in higher oil content of the product. Maltose concentration was significantly and positively correlated with the yield and fracturability of the product. RSM analysis indicated that the optimal combination of processing conditions was a VF temperature of 105 °C, VF duration of 25 min, and maltose concentration of 27%. Under these VF conditions, the silver herring products had a moisture content of 3.91%, Aw of 0.198, oil content of 21.69%, L* value of 28.19, ΔE of 27.31, and fracturability of 359 g/s. In summary, vacuum frying technology is suitable for the preparation of dried silver herring products, and this study can provide the optimal processing conditions for seafood processors to obtain better quality.

Fried Mugil cephalus was investigated under optimal vacuum and atmospheric conditions. The water distribution, texture, and color properties of vacuum-fried samples were enhanced compared with atmospheric-fried samples. Meanwhile, vacuum frying (VF) reduced the total oil content, protein oxidation, and degradation. The molecular weight and amino acid content suggested that protein was well-preserved during VF. In addition, the total carbonyl, free thiol groups, thiobarbituric acid reactive substances (TBARS), and Schiff base values were all significantly improved by the VF method compared to atmospheric frying (AF). VF inhibited the shift of amide bands to a higher frequency and the disordering of protein secondary structure. The sample surface morphology shrank under vacuum conditions, likely resulting in the lower fat content of vacuum-fried M. cephalus. Thus, VF improved the quality, water distribution, and microstructure and decreased the protein oxidation and degradation of M. cephalus and was considered a potential method for frying processing. [ABSTRACT FROM AUTHOR]

The study was carried out: a) to conduct vacuum frying below the triple point of water (VFBTPW) of frozen unmarinated beef slices using constant amount of sample used and frying temperature with different frying times and to determine the moisture and fat contents, product yield and rehydration, colour, and texture properties of the resulting vacuum fried products; b) to compare the physicochemical properties of VFBTPW and freeze-dried products; and c) to evaluate the structure of the vacuum fried beef slices using the scanning electron microscope. Vacuum frying of frozen unmarinated beef slices at 79±1°C, the lower the frying time the higher the moisture content of the vacuum fried product. The fat contents of the products were not significantly different with each other The frying time of 5 minutes gave the highest product yield due its high moisture content. The rehydration rate and rehydration ratio of the products were not affected by frying time despite a decreasing chamber pressure with increasing frying time. The chroma value of the products were not different from each other. The integrated force of the products decreased with frying time above 7.5 minutes. The vacuum fried product had lower moisture content but had higher fat content and product yield compared with the freeze-dried product. The rehydration rate and rehydration ratio of the vacuum fried product were lower than the freeze-dried product. The beef muscle fibres of the low moisture product were looser and more porous compared with the high moisture product which were more compact. The freeze-dried product was more porous than the low moisture vacuum fried unmarinated beef based on a transversal cut, but the reverse was observed when it was based on a longitudinal cut. [ABSTRACT FROM AUTHOR]

Potatoes are an important food crop that undergo postharvest storage, reconditioning, and cooking. Colored‐flesh varieties of potatoes are rich in phenolic acids and anthocyanins. Previous studies have suggested that purple‐flesh potatoes can inhibit colon cancer cells in vitro and reduce colon carcinogenesis in vivo. Vacuum frying (VF), as an alternative to conventional frying (CF), reduces fat content and may promote polyphenol retention in potato chips. We examined the impacts of reconditioning (storing at 13°C for 3 weeks following the 90‐day cold storage at 7°C) and frying method on phenolic chemistry and in vitro colon cancer stem cell (CCSC) inhibitory activity of purple‐flesh potato chips. We found that reconditioned chips exhibited higher total phenolic content (TPC) than nonreconditioned chips. We found that VF chips had lower TPC than CF chips. We observed no interaction between treatments. We found that VF chips had 27% higher total monomeric anthocyanin levels than CF chips, and observed a significant interaction between treatments. We found that VF chips had higher concentrations of caffeic acid (42%–72% higher), malvidin (46%–98% higher), and pelargonidin (55%–300% higher) than CF chips. We found that reconditioning had no effect. We found that VF chips had greater in vitro CCSC inhibitory activity than CF chips. Our results suggest that VF can improve the phytochemical profile and health‐related functionality of purple‐flesh potato chips, but additional studies are needed to determine if these results translate to the in vivo situation. Practical Application: Our current study shows that vacuum frying of purple‐flesh potato chips results in higher levels of total monomeric anthocyanins and concentrations of specific polyphenols as compared to chips produced by conventional frying. These differences correlated with better in vitro colon cancer stem cell inhibitory activity. Although additional in vivo studies are needed, our current results suggest that it may be possible for potato processors to improve the health‐related functionality of purple‐flesh potato chips through the use of vacuum frying. [ABSTRACT FROM AUTHOR]

Quick and accurate determination of oil content is extremely important to control the oil content of vacuum fried fruit and vegetable chips. This article uses fresh Pleurotus eryngii as raw materials to explore the influence of different vacuum frying times (0–14 min) on the moisture distribution, oil changes and quality of Pleurotus eryngii strips. The results show that as the frying time increases, the lateral relaxation time required for the taro strips to drop from the highest point of the signal amplitude to smooth becomes shorter and shorter, and the decay rate becomes faster and faster, that is, when the frying time is 14 minutes, The attenuation curvature and velocity are the largest. The oil content and brittleness of Pleurotus eryngii strips are significantly increased (P < 0.05); the water content is significantly reduced (P 0.05). At the same time, low-field NMR shows that the high-degree-of-freedom water in the pleurotus eryngii strips migrates to the low-degree-of-freedom water during the vacuum frying process. Among them, the free water in the pleurotus eryngii strips has a large degree of freedom. It has been removed, resulting in poor mobility and increased inability to flow. Part of the free water migrates to the semi-bound water, and most of the semi-bound water migrates outward as free water and then is removed. From this, all peaks are gradually removed. Moving to the left, the total peak area decreases. During the frying process, the T2 relaxation time of Pleurotus eryngii strips all shifted to the left, the total peak area is continuously reduced, the water content is getting less and less, the fat content is getting higher and higher, and the fat content distributed in the edge shell is always higher than Other locations. Low-field nuclear magnetic resonance technology can provide a fast, accurate, and non-destructive method for detecting moisture and grease for the vacuum-fried fruit and vegetable chips. As the frying time increases, the inner contour of the MRI image of Pleurotus eryngii strips gradually becomes blurred, the brightness gradually decreases, the volume shrinks, the less water, and the image interior is close to the background color (blue), indicating that the sample has reached the end of drying; and The grease content is distributed in the edge shell layer higher than other positions. Therefore, the water is continuously removed, the oil signal becomes stronger and stronger, and the oil content of the sample becomes higher and higher.

The aim of this study was to investigate the physicochemical characteristics and volatile flavor of fried tilapia skins under three frying methods. Conventional deep-fat frying usually increases the oil content of the fried fish skin and leads to lipid oxidation, which reduces the product quality. Alternative frying methods, such as air frying for 6 and 12 min under 180 °C (AF6, and AF12) and vacuum frying at 0.085 MPa for 8 and 24 min under 120 °C (VF8, and VF24) were compared to conventional frying for 2 and 8 min under 180 °C (CF2, and CF8) for tilapia skin. Physical properties of fried skin, such as the moisture content, water activity, L* values and breaking force decreased under all frying methods, while the lipid oxidation and a*, b* values increased with the increase in frying time. In general, VF offered higher hardness of product compared to AF which had a lower breaking force. Especially AF12 and CF8 had the lowest breaking force, which indicated higher crispness. For the oil quality inside the product, AF and VF reduced conjugated dienes formation and retarded oxidation compared to CF. The results of the flavor compositions of fish skin measured using gas chromatography mass spectrometry (GC/MS) with solid phase microextraction (SPME) showed that CF obtained higher unpleasant oily odor (nonanal, 2,4-decadienal, etc.), while AF presented greater grilling flavor (pyrazine derivatives). Because fish skin fried by AF only relied on hot air, Maillard reaction derived compounds, such as methylpyrazine, 2,5-dimethylpyrazine, and benzaldehyde were the leading flavors. This made the aroma profiles of AF very different from VF and CF. Among all the approaches, AF and VF developed lower oil content, mild fat oxidation and better flavor attributes, which proves their practical applications for frying tilapia fish skin.

Tomatoes are widely produced and consumed worldwide due to their high nutritional value as well as unique sensory properties. The high perishability and low shelf life of tomatoes necessitate the use of novel processing methods. In this research, the possibility of using vacuum frying technology in the processing of tomato slices, the effect of process variables (processing time, oil temperature and pressure inside the chamber) on some quality characteristics of the final product (moisture and fat content, shrinkage, ascorbic acid, color and texture brittleness) as well as determining the optimal processing conditions in a vacuum lab-scale frying systemwith precise control of process conditions were investigated. Initially, by performing pre-tests, the range of variables of the study included frying temperature (115-135°C), pressure inside the chamber (260-340 mbar) and process time (15-25 minutes) was determined. The results of study showed that the process temperature has significant effects (P≤0.05) on the moisture content, shrinkage, fat content, ascorbic acid content and texture brittleness, so that with increasing temperature, the moisture content and ascorbic acid content decrease and shrinkage, fat content and tissue brittleness increase. Processing time showed significant effects (P≤0.05) on the moisture content, shrinkage, fat content and texture brittleness, so that with increasing process time, the moisture content decreased and shrinkage, the fat content and texture brittleness, increased. Operating pressure had significant effects only on shrinkage and total color change characteristics (P≤0.05). Increasing the operating pressure led to a reduction in shrinkage and an increase in total color changes.Optimum vacuum frying conditions of tomato slices were a temperature of 135°C, time of 21.92 minutes and pressure of 260 mbar, under these conditionswere the moisture content, shrinkage, fat content, amount of ascorbic acid, total color changesand the breaking force were45.93%, 70.54%, 34.64%, 2.92 mg/100 mL, 64.86 and 2.58N, respectively. [ABSTRACT FROM AUTHOR]

Summary: Vacuum frying (VF) is a process developed at a pressure lower than atmospheric pressure, in which lower temperatures are employed to remove moisture from the food and reduce the oil content in the final product. Diverse studies have been published for VF or assisted with microwave and ultrasound, facing the challenges of accomplishing the physical and sensory properties appreciated in fried products. The studied matrices under VF include mainly vegetable origin foods (apple, banana, carrot, donuts, kiwi, mushroom, pea, pear, potato and sweet potato) and some animal origin products (chicken nuggets, fish fillets and surimi products). This review aimed to show recent and relevant findings of the application of VF, analysing both the effects on the frying medium and the impact on the fried foods. The inclusion of microwave and ultrasound technologies aids in the obtention of high‐quality products in terms of sensory and textural attributes, oil content as well as reduced oil degradation. This technique may provide safer and stable fried foods with lower oil content aiding in improving the diet of consumers and reducing production costs. [ABSTRACT FROM AUTHOR]

The main objective of this research study was to optimize vacuum frying of sausages with added chickpea flour. Pork fat was partial substituted with chickpea flour. A central orthogonal compound design is applied at different frying temperatures and frying times. The variables moisture loss and oil absorption were measured. The results showed that frying temperature was the factor that most affected moisture loss. Chickpea flour (9%) decreased fat absorption by ~15% at 152.34°C when compared to the control. Optimized values for frying temperature and time were 108.74°C and 5.08s respectively, with a desirability value of 0.64. It is concluded that vacuum fried sausages with added chickpea is a promising application for the industry since the optimized process significantly reduces oil absorption while maintaining favorable textural parameters. [ABSTRACT FROM AUTHOR]

Summary: This research evaluated the effects of process conditions on the physiochemical properties of vacuum‐fried durian chips. Ripened durians were sliced and fried at 90, 100, 110 and 120°C under 8‐kPa absolute pressure. From this study, microwave heating (MWH) during vacuum frying (VF) significantly reduced the frying time by 20% compared to VF (P < 0.05) with the effective moisture diffusivity for VF, pre‐treatment before vacuum frying (P+VF) and VF+MWH at 110°C determined to be 3.63 × 10−09, 4.30 × 10−09 and 4.84 × 10−09 m2 s−1, respectively. VF+MWH produced chips with significantly lower shrinkage, more yellowness (P < 0.05) and higher crispiness (consistent with the microstructure from scanning electron microscopy (SEM)). In addition, VF+MWH drastically decreased oil absorption by 10%, while P+VF yielded the lowest specific energy consumption (SEC). From sensory evaluation, the overall acceptability of VF+MWH chips rose from 5.83 to 6.07 (seven‐point hedonic scale), thus making the product fall into the 'Good' to 'Very Good' range. [ABSTRACT FROM AUTHOR]

Vacuum frying conditions were investigated with respect to physical, chemical and sensorial properties of French fries and frying oil, besides determining the effect of frying conditions in terms of frying temperature and time. In order to determine the optimum frying conditions of the French fries optimization study was carried out according to Central Composite Rotatable Design. The results were evaluated to determine optimum vacuum frying conditions targeting minimum oil content, 30–45 N in range of hardness, minimum acrylamide content and maximum overall preference. The optimum vacuum frying condition was selected as 124.39 °C of frying temperature and 8.36 min of frying time for French fries. The French fries obtained at optimum conditions for vacuum frying preserved the desired color, textural properties and flavor and it has low oil content and reduced acrylamide formation. In addition, the frying oil quality was preserved with vacuum frying.

This article examines the capability of microwave-assisted vacuum frying (MWVF) on saving frying time and quality improvement of fried banana chips. The MWVF machine was designed to combine vacuum frying (VF) and microwave heating (MW) in which electromagnetic distribution was simulated by COMSOL Multiphysics application software. Fresh banana chips were fried at 95 °C and 2 kPa, at various vacuum frying times (25–75 min), and at microwave heating times of 5 and 10 min. The quality of the banana chips was considered in terms of moisture, oil content, texture, color, and sensory attributes. The results showed that MWVF could provide a significantly shorter frying time than VF, from 75 min to 50 min (VF40MW10). The MWVF techniques were able to preserve the quality of banana chips similar to the VF method. The banana chips made by MWVF had a better sensory evaluation than the ones fried only by vacuum.

Deep-frying is the century-old and the most common cooking process which is still being used to prepare a variety of food products in industrial and domestic scales. Compared to other cooking processes, frying produces some distinctive flavor characteristics, but other undesirable and unacceptable characteristics to consumers are also originated during frying. Researchers have taken various technical approaches for reducing the oil content of fried products without compromising product quality. This review discusses some recently developed frying techniques which could improve the product quality, and advance frying efficiency, to save energy cost. Some modified method of alternative frying technologies used by the researchers are vacuum frying, microwave frying, microwave-assisted vacuum frying, radiant frying, ultrasound treated frying, air frying or their combinations. In this review, we aim to give a detailed insight into some specific aspects of new deep-frying practices and pretreatments for the quality maintenance of fried products highlighting their novelty and efficiency. [ABSTRACT FROM AUTHOR]

The fat content of fried pork rinds is high, and alternative frying helps reduce the oil content and maintain their texture and taste. Different frying methods such as microwave-assisted, traditional deep frying and vacuum frying on the breaking force, color, microstructure, water loss and oil absorption attributes of fried pork rinds were evaluated in this study. The fat content of microwave-assisted and vacuum-fried pork rinds was lower (24.2 g/100 g dry weight basis (db) and 17.1 g/100 g db, respectively) than that (35.6 g/100 g db) of traditional deep-fat frying. Nonuniform, holy and irregular surface microstructures were obtained by vacuum frying due to rapid mass transfer at low pressure. The first-order kinetic models of water loss and oil absorption of traditional and microwave-assisted frying of pork rinds were established. Microwave frying caused a faster moisture loss rate, shorter frying time and lower pork rind oil content, makes it an attractive substitute for traditional deep-fat frying. [ABSTRACT FROM AUTHOR]

Copyright of Indonesian Journal of Human Nutrition is the property of Brawijaya University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Squid are commercial marine species that have high nutritional value. This study aimed to compare the influences of vacuum frying and atmospheric frying on the physicochemical properties and protein oxidation of three main parts (ring, tentacle, and fin) of the squid Loligo chinensis. The results showed that the vacuum‐fried (VF) group had lower moisture and total fat contents and looser microstructures than the atmospheric‐fried (AF) group. The amino acid contents and molecular weight revealed that the proteins were well preserved during vacuum frying. Carbonyl content in the VF ring, tentacle, and fin samples increased nearly 2.53‐, 1.54‐, and 2.56‐fold, respectively, compared to that in the corresponding fresh group, but these increases were lower than those of the corresponding AF group. In addition, the secondary structures of proteins revealed a slight decrease in the α‐helix and β‐turn contents and a significant increase in the β‐sheet content during vacuum frying. Therefore, vacuum frying can be used as an efficient processing method to conserve the high nutritive quality of the product. Practical Application: As a developing alternative technology to prepare healthier fried products, vacuum frying has been the focus of recent researches. Vacuum frying produced squid products that had lower TBARS values, carbonyl contents, and Schiff base substances compared to atmospheric frying. And the protein secondary structures of the vacuum‐fried group retained better. The study proved that vacuum frying could be an effective method with the advantages of high protein stability and product quality. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Vacuum frying (VF), which combines sonication, with microwave heating was used to evaluate the quality attributes of fried mushroom chips as well as the stability of the frying oil. Frying was performed at 90 °C, 0.015 MPa, 1000 W microwave power input at two ultrasound power levels. Mushroom (Agaricus bisporus) chips were fried using four frying conditions, namely: VF, microwave vacuum frying (MVF), 300 W ultrasound-assisted MVF (300UMVF), and 600 W ultrasound-assisted MVF (600UMVF). The fried samples were evaluated in terms of their moisture content, oil content, protein content, bioactive compounds (total phenolic compound, total flavonoid compound), and color characteristics. The 600UMVF sample required less processing time to reach at the same final moisture content. The oil content was also found to be lower in the high-power sonicated sample. The contents of protein, total phenolic compound, and total flavonoid compound in the fried mushroom chips (FMC) were preserved to a greater extent by the ultrasound treatment. All fried samples displayed natural color; the best result found for the 600UMVF sample. UMVF was found to delay oil deterioration by enhancing its oxidative stability. Microstructure observations revealed that the cell structure of the fried sample is preserved better by the ultrasound treatment. The findings of this work show that sonication-enhanced frying minimizes the loss of nutrients, bioactive compounds, and preserves the color of the original sample. [ABSTRACT FROM AUTHOR]

Chicken "isaw," which is common street food in the Philippines, is prepared by conventional frying and is observed to have poor shelf-life and keeping qualities. Hence, a new product was developed employing vacuum frying technology to minimize undesirable changes and provide longer shelf-life as the conditions under vacuum frying involves the use of low temperature and minimal exposure to oxygen. However, data on its quality is not yet available since the product is new. Thus, the development of sorption isotherm and understanding of isosteric heat of sorption to the newly developed product is essential for the quantitative approach to predicting stability and quality changes during packaging and storage. Isotherms of vacuum fried chicken "isaw" were measured at 20 °C, 30 °C, and 40 °C by the static gravimetric method over a range of relative humidity (RH) from 7-75%. BET (up to 43% Aw), Smith, Kuhn, Oswin, Karel, and Peleg were the mathematical models used in fitting the experimental sorption data. Corresponding to BET, the monolayer moisture content (Xm) revealed that the vacuum fried chicken "isaw" must have a moisture content of 3.79%, 1.98%, and 1.96% at 20 °C, 30 °C, and 40 °C, respectively to prevent auto-oxidation and to enhance product stability of vacuum fried chicken "isaw" during storage. The net isosteric heat was calculated using the Clausius-Clapeyron equation and was observed that as moisture content is decreased, the isosteric heat of sorption increases. With these data gathered, generating and understanding the product's sorption isotherm, energy constants, and general equation at 20 °C, 30 °C, and 40 °C would provide valuable information for predicting quality changes during storage and packaging and for convenience in its future processing in an attempt to improve its quality, safety, and profitability. [ABSTRACT FROM AUTHOR]

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)