The optimization of the deep-fat frying process of coated zucchini pieces by response surface methodology

The effect of Carboxymethyl cellulose (CMC) gum in three concentrations of 0.5, 1, and 1.5% (w/v) was investigated on the oil uptake and qualitative properties (moisture content, color, and overall acceptance) of zucchini during frying at 150, 165, and 180°C for 1, 3.5, and 6 min. To determine optimum conditions of frying operation, the response surface methodology (RSM) was used. Based on the modeling performed, the lowest oil uptake (1.93%) was determined for the coated samples with concentrations of higher than 0.75% of CMC gum and fried at temperatures less than 157.5°C for 2.25 min. The optimization results of RSM showed that oil uptake of zucchini coated with CMC gum during frying is decreased significantly (p < 0.05) with the reduction of operation time and temperature, and concentration of CMC gum. Optimum conditions for decreasing oil uptake of coated zucchini pieces were 153.46°C, 0.5%, 1.03 min for temperature, concentration and time, respectively.     

Changes in ascorbic acid,beta‐carotene and sensory properties in Sundried and stored Amaranthus hybridus vegetables

Amaranthus hybridus was grown as a leafy vegetable in Dar‐Es‐Salaam, Tanzania. Freshly harvested leaves were analyzed for moisture content, beta‐carotene and reduced ascorbic acid. The leaves from the four sites were bulked, blanched and sundried with shade provision drier. The dried samples were stored in polythene bags at 22°C, 28°C and room temperature (30°C to 32°C). At the beginning and thereafter every month during storage, the vegetables were analyzed for beta‐carotene and ascorbic acid and subjected to sensory evaluation in comparison with fresh cooked leaves.

Sundrying of the amaranth leaves resulted in significant reductions (P < 0.05) in the levels of ascorbic acid and beta‐carotene, of 87.4% and 16.3% respectively. After storage of the dried vegetables for three months, the retention at 22 ° C, 28 ° C and room temperature of ascorbic acid and beta‐carotene were 42, 40 and 36 mg/100g and 32.4, 29.5 and 27.4 mg/100 g dwb respectively. Sensoric quality evaluation of amaranth leaves showed that significant differences (P < 0.05) existed in appearance and colour, flavour, texture and overall acceptability, although the dried vegetables were still acceptable in all the sensory characteristics tested. The study established that the vegetables could be dried to produce an acceptable product which maintained its eating quality for up to three months in storage.     

Evaluation of the stability of a spray-dried tuberculosis vaccine candidate designed for dry powder respiratory delivery

Particle engineering via spray drying was used to develop a dry powder presentation of an adjuvanted tuberculosis vaccine candidate. This presentation utilizing a trileucine-trehalose excipient system was designed to be both thermostable and suitable for respiratory delivery. The stability of the spray-dried vaccine powder was assessed over one year at various storage temperatures (-20, 5, 25, 40, 50 °C) in terms of powder stability, adjuvant stability, and antigen stability. A formulation without trileucine was included as a control. The results showed that the interior particle structure and exterior particle morphology of the powder was maintained for one year at 40 °C, while the control case exhibited a small extent of particle fusing under the same storage conditions. Moisture content was maintained, and powder solid state remained amorphous for all storage temperatures. Aerosol performance was assessed with a commercial dry powder inhaler in combination with a human mouth-throat model. The emitted dose and lung dose were maintained for all samples after one year at temperatures up to 40 °C. Nanoemulsion size and oil content of the adjuvant system were maintained after one year at temperatures up to 40 °C, and the agonist content was maintained after one year at temperatures up to 25 °C. The antigen was completely degraded in the control formulation at seven months of storage at 40 °C; by contrast, 45% of the antigen was still present in the trehalose-trileucine formulation after one year of storage at 50 °C. Comparatively, the antigen was completely degraded in a liquid sample of the vaccine candidate after only one month of storage at 37 °C. The spray-dried trehalose-trileucine vaccine powder clearly maintained its inhalable properties after one year’s storage at high temperatures and improved overall thermostability of the vaccine.     

The influence of the closure format on the storage stability and moisture content of freeze-dried influenza antigen

Low moisture content is seen as crucial to achieving long term stability of freeze dried biologics and reference materials. Highly hygroscopic freeze-dried material are susceptible to moisture ingress over time which can lead to degradation and loss of biological potency. This study compared vials with unprocessed stoppers, vials with vacuum-oven dried stoppers and glass ampoules in order to determine the superior long term storage format in terms of moisture ingress and potency. B/Phuket influenza antigen was chosen as the model biological standard and the lyophilized antigen was stored at −20, 25 and 45 °C over a 1 year period. Ampoules had no significant moisture change across all storage temperatures as would be anticipated. Moisture content results at −20 °C showed no significant differences between ampoules, vials with vacuum-oven dried stoppers and vials with unprocessed stoppers over 12 months. Vials with vacuum-oven dried stoppers performed similarly to ampoules at −20 °C and 20 °C, but had a small increase in moisture content after 6 months at 45 °C. Vials with unprocessed stoppers preformed the worst and exhibited the largest moisture ingress after just 3 months at both 20 °C and 45 °C. Single radial immunodiffusion (SRD) potency assays showed at −20 °C and 20 °C there was no significant difference between all closure formats. At 45 °C there was a drop in potency for all closure formats, but ampoules and vials with vacuum-oven dried stoppers retained higher potency than vials with unprocessed stoppers. Thus, while ampoules are still considered to be the gold standard format for long term storage stability, using vials with vacuum-oven dried stoppers provides comparable stability and moisture integrity at −20 °C and 20 °C storage.     

Effect of blanching and drying temperatures on the physicochemical characteristics,dietary fiber composition and antioxidant-related parameters of dried persimmons peel powder

The effects of blanching with hot water at 90°C for 2 min and hot-air drying temperatures (50°C, 60°C and 70°C) on the physicochemical properties, dietary fiber compositions, antioxidant activity and hydration properties of ripe, soft persimmon peels were investigated. Blanching and drying significantly reduced the retention of antioxidant-related parameters. Although there were no significant differences in total phenolics and β-carotene content at different drying temperatures for both dried unblanched and blanched peels, dried blanched peels had higher dietary fiber compositions and swelling capacity than those of dried unblanched peels at all drying conditions. In addition, blanched peels dried at 50°C had the highest dietary fiber compositions, swelling capacity and antioxidant activity compared with those at high drying temperatures (60°C and 70°C). Therefore, blanched peels dried at 50°C is suggested to obtain better quality dietary fiber powder from persimmon peel for use in food applications or in fiber-fortified foods for health promotion.     

Dough Characteristics,Baking Performance,and Staling of Taftoon Bread as Affected by Supplementation with Sesame Oil

Taftoon bread is one the main traditional flat breads consumed in Iran and various parts of the Middle East. We studied the effect of different levels (1–3% w/w flour-based) of sesame oil on dough characteristics, baking performance, and staling of Taftoon bread during storage (5 days) in room (25 ± 1°C) or refrigerator (4 ± 1°C). Supplementation of dough with 1 or 2% oil led to improved Farinograph characteristics. Breads with 2% oil showed higher oven spring and specific volume and lower baking loss. The moisture and water-soluble starch content of the oil-added samples were higher, but their firmness was less than the control bread. Supplementation of bread with oil led to a lighter Hunterlab color and improved sensory scores. Generally, the best quality was obtained at the optimum usage level of 2% sesame oil. Bread staling, as monitored by moisture, water-soluble starch, and firmness analysis, was slower in refrigerator than in room.     

Mutagenic activity of heated potato/oil systems

Mutagens detected with Salmonella typhimurium strain TA 98 in the presence of liver S9 mix were extracted from potato slices, but not pure potato starch, after frying in oil. No mutagenic activity was detected using strain TA 100, in the presence or absence of S9 mix with either fried potato slices or potato starch. Mutagenic activity was detected at frying temperatures of 140°C and above. The mutagenic activity was limited to the outer portion of the fried potato slices and increased with frying time and temperature. Mutagenic activity ratios for extraction with both (NH4)2SO4/ NH4 OH and Na2 SO4 /NaOH were similar.     

Effect of incorporation of mushroom (Pleurotus sajor-caju) powder on quality characteristics of Papad (Indian snack food)

Papad is familiarly known as an Indian food adjunct or snack food. In this study, attempts have been made to increase the protein, minerals and crude fibre content of the papad with incorporation of Pleurotus sajor-caju powder to develop a novel snack food. Mushroom powder was added in different proportions with other ingredients of the papad and the prepared papad was subjected to physicochemical and sensorial analyses. Mushrooms pretreated with 1% potassium metabisulphite followed by whey treatment had better colour and reduced drying time. Drying at 50°C produced more amount of mushroom powder (350 μ) and had higher acceptability of rehydrated samples. The papad enriched with 20% mushroom powder showed increased values of protein (15.8%), minerals (38.87%) and crude fibre (218.18%) content and had maximum sensory score. Therefore, papad supplemented with oyster mushroom powder may help to reduce protein malnutrition, constipation and mineral deficiency disorders.     

Palm oil and palm olein frying applications

Several million tones of palm oil and palm olein are used annually in the world for frying. This paper will discuss their frying performances in three major applications - industrial production of potato chips/crisps, industrial production of pre-fried frozen French fries and in fast food outlets. In the first study, about four tones of potato chips were continuously fried 8 hours a day and five days a week. The palm olein used (with proper management) performed well and was still in excellent condition and usable at the end of the trial. This was reflected in its low free fatty acid (FFA) content of around 0.23%, peroxide value of 4 meq/kg, anisidine value of 16, low polar and polymer contents of 10% and 2%, respectively, induction period (OSI) of 21 hours and high content of tocopehrols and tocotrienols of 530 ppm even after >1900 hours. In the second study in which an average 12 tones pre-fried frozen French fries were continuously fried a day for 5 days a week, palm oil performed excellently as reflected by its low FFA of 0.34%, food oil sensor reading of 1.1, low polar and polymer contents of 17% and 2.8%, respectively, over the 12 days of trial. In the third study in which palm shortening, palm oil and palm olein were simultaneously used to intermittently fry chicken parts in the laboratory simulating the conditions in fast food outlets, the three frying oils also performed very satisfactorily as reflected by their reasonably low FFA of <1%, smoke points of >180 degrees C, and polar and polymer contents of <25% and <6%, respectively, after 5 days of consecutive frying. All the quality indicators did not exceed the maximum discard points for frying oils/fats in the three applications, while the fried food product was well accepted by the in-house train sensory panel using a-nine point hedonic score.     

Maternal intake of fried foods and risk of gestational diabetes mellitus

PurposeWe examined the relationship of maternal periconceptional (i.e., before conception and early pregnancy) intake of fried foods with gestational diabetes mellitus (GDM) risk.MethodsIn a prospective birth cohort in Seattle and Tacoma, Washington State, USA, we assessed maternal periconceptional fried food intake using a food frequency questionnaire among 3414 participants. We used multivariable generalized linear regression models to derive estimates of relative risks (RRs; and 95% confidence intervals, 95% CIs) of GDM in relation to the intake of different types of fried foods (i.e., fried fish, fried chicken, fried potatoes, chips, and donuts).ResultsA total of 169 GDM incident cases were identified in this cohort (4.96%). Compared with no fried fish intake, fried fish intake >1 servings/month was associated with 68% higher GDM risk (adjusted RR and 95% CI; 1.68 [1.16, 2.45]; P_trend = .019). After adjusting for confounders, the RRs (95% CI) of GDM relative to fried chicken intake were 1.0, 1.44 (0.98, 2.09), and 1.81 (1.22, 2.70) for none, ≤1 and > 1 servings/month intake of fried chicken, respectively (P_trend = .002). Dietary intake of fried potatoes, snack chips or donuts was not significantly associated with higher GDM risk. Limitations of our study include the lack of information about frying methods and the intake of fried foods at home and away from home.ConclusionsRegular intake of fried fish and fried chicken are associated with elevated GDM risk.     

Formation of trans fatty acids in chicken legs during frying

The formation of trans fatty acids in chicken legs during frying in unhydrogenated and hydrogenated soybean oil was studied. Frying was conducted at 160°C, 180°C and 200°C for 15, 30, 45, 60 and 75 min, with the various cis and trans fatty acids being analyzed in unhydrogenated and hydrogenated soybean oil, as well as chicken leg meat and chicken leg skin, using a gas chromatography–mass spectrometry technique. Results showed that the amounts of most fatty acids decreased along with increasing frying temperature and frying time when fried in unhydrogenated or hydrogenated soybean oil. No trans fatty acids were formed in chicken leg meat fried in unhydrogenated or hydrogenated soybean oil. Instead, the formation of trans fatty acids was observed in chicken leg skin fried in hydrogenated soybean oil, probably because of oil absorption. A maximum level of trans fatty acids occurred 15 min after frying and then declined thereafter.     

Mini-papad containing cheese powder--a novelty snack food

The present work reports on attempts to develop mini-papads containing cheese powder to create a novel taste, with potential for urban and export markets. Cheese powder was added to black gram flour at 0-50% levels and papads were prepared in the conventional manner by rolling the dough and drying. These papads were deep-fat fried at 180 degrees C. Upto 20% addition of cheese powder gave no perceptible change in taste or flavour of the mini-papads. At 30% addition brown colouration was observed which decreased the sensory appeal. At 40 and 50% levels, although the mouthfeel and flavour of cheese was desirable, browning increased markedly, which drastically lowered the overall acceptability. Ascorbic acid addition at 0.5-1.0% markedly decreased the browning. The papads had a higher fat content on frying as compared to the control but were excellent organoleptically, suggesting them to be a tasty and crunchy snack food.     

Studies on the Production of Red-Kidney-Bean Tempeh

Red kidney beans of the Canadian Wonder variety can be used as a substrate for production of a fermented tempeh-like product using Rhizopus oligosporus.

The optimum conditions for fermentation require soaking, dehulling, and boiling of beans for 20 min followed by innoculation and incubation at ambient temperatures for 48 hours. The fermentation is accompanied by increases in crude-protein and fibre content, as a direct function of time and temperature of incubation and by Increases in soluble solids content.

Mould growth may take place at pH as low as 4.5 and up to an optimum of 6.8. Beyond pH 7, degradative odour and flavour changes are observed. The ripe tempeh when steamed to arrest further mould growth, had good storage stability for up to two weeks at 4 ° C. The bean tempeh had good acceptability When served fresh, boiled or fried.

The cooking time for preparation of dried beans in a ready-to-eat palatable form has been effectively reduced to less than half an hour.     

Fatty acids characterization and oxidative stability of spray dried designer egg powder

Background

Designer eggs (DEs) have gained positive importance in maintaining cholesterol level, triglyceride profile and protection towards cardiovascular diseases due to the presence of essential fatty acids (EFAs) such as omega-3 (or) n-3 fatty acids. However, extreme heat conditions effect the quality as well as quantity of EFAs during the production of designer egg dried powder (DEDP). Therefore, the main mandate of research was the development of DEDP and determination of spray drying conditions impact on fatty acids composition of DEDP samples.

Methods

The DEs were produced, collected, de-shelled, homogenized and diluted before spray drying to get fine powder. The spray drying of DEs was carried out using a laboratory spray drier. An experimental design was used for the drying parameters, where the inlet air temperature was varied (160, 180 and 200?°C), feed flow rate (200, 300 and 400?mL/hr), atomization speed (16,000, 20,000 and 24,000?rpm) and outlet air temperature (60, 70 and 80?°C) at different levels. For convenience of experimental design coding was used. The DEDP was collected in a single cyclone separator and was stored after packaging for consecutive 2?months at 25?°C and 4?°C, respectively. The powder yield was calculated from the collected dry mass in the collecting vessel divided by the processed whole egg diluted matter. The total lipids of DEDP samples were determined gravimetrically. The esters of fatty acids in each sample were prepared and analyzed through Gas Chromatograph apparatus. The oxidative stability of DEDP samples was estimated by following standard procedure of peroxide value.

Results

The powder yield of DEDP as a result of different operating conditions was found in the range of 30.06?±?0.22?g/500?mL to 62.10?±?0.46?g/500?mL DEs sample. The decreasing trend in moisture content (4.4?±?0.16% towards 4.0?±?0.09%) and total fat content (45?±?0.65?g/100?g towards 41?±?0.35?g/100?g) in DEDP samples was observed with increased inlet and outlet temperature while fat content increased at high feed flow rate and atomization speed. In this study, loss of PUFAs in DEDP samples was followed due to their active role regarding to human health. For alpha-linolenic (ALA) fatty acids, maximum value at 4?°C observed was 127.32?±?0.27?mg/50?g egg and 124.43?±?0.32?mg/50?g egg while the minimum value observed for ALA was 100.15?±?0.09?mg/50?g egg and 97.15?±?0.06?mg/50?g egg after 30 and 60?days storage, respectively. The significant decrease trend for eicosapentaenoic (EPA) fatty acids values from 11.78?±?0.31?mg/50?g egg to 2.18?±?0.14?mg/50?g egg at 25?°C under spray dried conditions of inlet air temperature (180?°C), feed flow rate (300?mL/hr), atomization speed (24,000?rpm) and outlet air temperature (80?°C) after 60?days storage period was noted. The docosahexaenoic (DHA) fatty acids value in DEDP was decreased from 15.49?±?0.79?mg/50?g egg (0?day) to 10.10?±?0.64?mg/50?g egg at 60?days (4?°C) and same decreasing trend was observed at 25?°C. The decreasing order for total omega-3 fatty acids retention in DEDP during storage intervals was found as 162.33?±?1.64?mg/50?g egg >?158.61?±?1.53?mg/50?g egg >?148.03?±?1.57?mg/50?g egg (0, 30 and 60?days stored at 4?°C) and 162.33?±?1.64?mg/50?g egg >?151.56?±?1.54?mg/50?g egg >?135.89?±?1.62?mg/50?g egg (0, 30 and 60?days stored at 25?°C). The peroxide value (PV) levels obtained in DEDP samples after 60?days were higher (0.78?±?0.06, 0.81?±?0.02?meq/kg O₂) when compared to initial readings at 0?day (0.65?±?0.04?meq/kg O₂). The PV of DEDP samples reached their maximum peaks after 60?days at 25?°C. The increasing order showed that lipid oxidation increased with storage. However, the overall PV never exceeded the limit of 10 (meq/kg) considered as a threshold limit.

Conclusions

Extreme hot conditions (>?180?°C) of spray dryer reduce the quality of designer egg dry powder. Extreme conditions assist PUFAs loss and decrease in storage stability due to high lipid oxidation.

     

Development of an Optimized Cassava Starch-Based Custard Powder

Custard powder is a dry-formulated food product primarily made from imported corn starch in developing countries. To reduce over-dependence on corn starch, this study investigated its replacement with yellow-fleshed cassava root starch (YfCRS) in custard powder formulation. Response surface methodology was used to develop an optimized cassava starch-based custard powder based on various combinations of YfCRS (90–98%) and whole egg powder (WEP) (2–10%). The result showed that the blends of YfCRS and WEP led to custard powder with wide functional, physicochemical, chemical, and micronutrient properties, with sensorily acceptable gruel. The second order response surface regression model accurately predicted most of these quality parameters (R2 > 0.90). The optimum formulation achieved to produce an acceptable custard was 90% YfCRS and 6.07% WEP. Therefore, this study showed that YfCRS might be a very good replacement for corn starch in the production of an acceptable custard.     

Nutritional composition of freshly harvested and stored Latvian potato (Solanum tuberosum L.) varieties depending on traditional cooking methods

The information about nutritional composition of potatoes at both the ingredient and recipe levels in the Food Composition Data Base (FCDB) of Latvia is insufficient. Therefore, the aim of this research was to determine the nutritional composition and energy content of potatoes prepared by traditional cooking methods before and after storage. Five Latvian potato varieties were selected: Lenora, Brasla, Imanta, Zile and Madara. A two-year research was conducted during two periods: just after harvesting (2007, 2008) and after six months of storage (2008, 2009). The following cooking methods were used: shallow frying (150 ± 5 °C); deep-fat frying (180 ± 5 °C) and roasting (210 ± 5 °C). The weight of the potatoes was recorded before and after frying along with the time and temperature during frying. Chemical analyses were performed to determine the content of reducing sugars, starch, fructose, glucose, sucrose, fibre, fat, protein, moisture, vitamin C and amino acids. The content of the analyzed nutrients differed significantly between both potato varieties and applied cooking methods: differences between potato varieties and cooking methods were found for vitamin C, moisture, reducing sugars, fructose, glucose, sucrose, amino acids, essential amino acids, and energy content, whereas significant differences in starch, fibre, fat and protein content were found between cooking methods.     

Quality,Functional, and Sensory Properties of Cookies from Sweet Potato–Maize Flour Blends

This study was carried out to determine the quality, functional, and sensory properties of cookies from sweet potato–maize flour blends. Substitution of maize flour with sweet potato flour was done at 10–100%. Values of bulk density, water binding capacity, dispersability of flour samples, swelling power of starches, starch content, sugar content, cookie flow, calorific values, and proximate composition were determined. The results revealed that substitution of sweet potato flour with maize flour significantly (p < 0.05) reduced the protein from 6.8–4.4%, moisture from 5.3–5.0%, crude fiber from 3.4–2.5%, and fat from 9.8–8.5% of the composite flours and the cookies. The ash and sugar contents were increased from 4.3–5.8% for ash and 2.1–3.9% for sugar with increase in sweet potato flour substitution. The calorific value of the cookies decreased from 457–397cal/100 g as the percentage of sweet potato flour increased in the maize flour cookies. The water binding capacity increased from 0.9–1.7 and the starch swelling power decreased from 10.1–5.3 at 95°C with increase in sweet potato flour content in the flour mixture. The bulk density and dispensability decreased from 4.6–3.3 g/ml and 48.3–47.1 ml/g, respectively, in the flour as the content of the sweet potato flour in the composite flour increased. Sensory evaluation results showed that the colour, texture, taste and overall acceptability changed significantly (p ≤ 0.05) with increase in sweet potato flour substitution. The optimum substitution level was 40%. Above this level of substitution, the product becomes less acceptable to the consumer in terms of all the variables studied.     

Nutritional, sensory and physical analysis of pumpkin flour incorporated into weaning mix

The objective of this study was to develop a cereal-pulse complementary food fortified with different concentrations of pumpkin powder (Cucurbita moschata), and to analyse its sensory and physic-chemical parameters. Fresh pumpkins(Cucurbita moschata) were procured from the market and dehydrated and powdered in the laboratory. Sorghum (Sorghum vulgare) and whole green gram (Vigna radiate) were germinated, dried, pulverised and combined with powdered rice (Oryza sativa) in the ratio of 2:1:1. Pumpkin powder was added to this mixture at 10%, 20% and 30% variations. The complementary weaning food mix was subjected to sensory analysis (appearance, colour, flavour, texture and overall acceptability) by semi-trained panelists. The mix was analysed for its moisture, energy, protein, fat, carbohydrates, fibre, beta-carotene and anti-oxidant content. Nutritional analysis of the weaning mix demonstrated that there was a significant increase in the protein, fibre, carbohydrate and antioxidant levels with an increase in concentration of pumpkin powder. The sensory analysis revealed that the complementary food mix with 20% pumpkin powder fortification had good sensory qualities.     

Frying of Food: A Critical Review

Deep fat fried foods are very popular food because of their unique quality characteristics. The process is based on the immersing food at high temperatures, depending on the raw materials, thereby leading to physical and chemical changes such as starch gelatinization, protein denaturation browning, and crust formation. In order to obtain a product with a low fat content, it is essential to understand the mechanisms involved during the frying process so that oil migration into a food product can be minimized. The purpose of this study is to review literature findings on frying of food. The review also aims to draw the attention of stakeholders, including decision makers, on the need to assess the health risks associated with consumption of fried food product and, consequently, the necessary measures and steps to reduce such risks in order to have safer food in the world.