Increase In Acid Value Research Articles

Physicochemical characteristics of cold-pressed blackcurrant-, strawberry-, and raspberry seed oils during storage and its influence on thermo-oxidative stability

The storage characteristics of cold-pressed blackcurrant-, strawberry- and raspberry seed oils and the factors influencing thermo-oxidative stability during storage were determined. It was established that throughout one year there were no significant (p ≤ 0.05) changes of thermo-oxidative stability (OIT at 120 and 140 °C) and fatty acid composition in all berry seed oils (BSO), despite a minor reduction in antioxidant activity (DPPH radical scavenging) and tocopherol content, and an increase in acid value, p-anisidine value, and K232, K268 values. Pigment degradation became noticeable after 6 months, resulting from a decrease in chlorophyll and carotenoid content, and observed in changes of colour parameters (angle hue, chroma, ΔE). The study also showed that many compositional factors play an important role in maintaining the thermo-oxidative stability of berry seed oils at a constant level over a period of one year, among which the most significant parameters influencing OIT values were the content of fatty acid c18:1, tocopherols and carotenoids, as revealed by the multiple linear regression analysis (MLR).

Physical and Chemical Properties of Boiled Oil: A Traditional Method of Extracting Oil from Boiled Olive Fruits

Background In some villages in Northern Jordan, farmers boil part of their olive fruit harvest before oil extraction to increase the quantity of oil, get a desirable acquired taste, as they claim, and get additional health benefits. Locals call this oil Boiled oil (BO), and its price is about 20% higher than virgin olive oil (VOO) produced by the same farmer. Objective The hypothesis was that boiling olive fruits may affect the quality of the produced oil. Therefore, our study aimed to determine the chemical and physical characteristics of boiled oil in comparison with VOO and the effect of storage of both types of oils for one year. Methods Total phenolic compounds, ferric-reducing antioxidant power assay (FRAP), and radical scavenging activity (RSA) were evaluated. Moreover, the quality indices of BO and VOO were also evaluated. Results Total phenolic compounds decreased significantly (p <0.05) from 8.7 mg GAE/100g in VOO to 2.47 mg GAE/100g in BO. The antioxidant activity measured using FRAP assay also decreased significantly (p <0.05) from 962 to 379 micromole/kg. Half-maximum inhibitory concentration (IC50) of the RSA was significantly higher (p <0.05) in BO samples (414 mg/ml) in comparison with VOO samples (38.9 mg/ml). Moreover, there was a significant increase (p <0.05) in acid value in BO samples (0.943%) in comparison with VOO samples (0.518%). However, the increase in acid value after one year of storage was higher in VOO than in BO. The peroxide value also increased significantly in boiled oil (500 meq/kg) in comparison with VOO (19 meq/kg). Additionally, a significant increase in ultraviolet absorption was observed in BO at k232 and k270 (3.5), which is considered unsuitable for human consumption compared with VOO (2.43). Conclusion In conclusion, these results showed that boiling olive fruits before oil extraction deteriorates oil quality as expected, and consumers should be educated that this type of oil is hazardous to human health and is a waste of effort and money.

Influence of Extraction Temperature on the Quality of Neem Seed Oil: Preliminary Investigation

The storage of neem oil for a long time before usage comes along with challenge of quality retain ability of the oil; and the extraction methods can affect the quality of neem seed oil. This research work compared the mechanical expression method to the solvent extraction method to find a better method that will give high-grade neem oil for long-term storage. A plant with a capacity of 50 kg/day of neem seed kernel was used to extract oil from neem seed using ethanol as extraction solvent. The increase of extraction temperature from 20 oC (mechanically expressed) to 78 oC leads to decrease of iodine value from 62.70 to 60.10 gI2/100 g; increase of acid value from 3.4 to 4.2 mg KOH/g and increase of saponification value from 158.74 to 210.18 mgKOH/g. The Fames standard method was used for the GC – MS analysis and the percentage composition of the polyunsaturated components in the 20 oC (mechanically expressed), 50 oC, 55 oC, 60 oC and 78 oC oils were 21.58, 6.33, 3.09, 1.83 and 0.21% respectively. The changed of extraction temperature from 20 oC to 78 oC brings about reduction of polyunsaturated components from 21.58% to 0.21%. The increase of extraction temperature leads to conversion of unsaturated components to saturated components due to auto – oxidation process. This is clearly seen as the extraction temperature increased from 20 oC to 78 oC, the percentage composition of the saturated components increased from 22.40% to 43.70% and the polyunsaturated component decreased from 20.47% to 0%. The fatty acid composition associated with the 78 oC oil are: Oleic acid, 46.61%; Stearic acid, 11.83%; Palmitic acid, 16.54%; 11 – Octadecenoic acid, 3.58%; Cis – Vaccenic acid, 5.90%; Cyclopropaneoctanal, 11.19%; Squalene, 0.21% and Trimethylsilyl – di(timethylsiloxy) – silane, 4.14%. The functional groups identified in the 78 oC oil were C – H, C = O, C – C and C – O. Based on the lowest iodine value, lowest percentage composition of the polyunsaturated component value and high percentage composition of saturated component, the neem oil obtained at 78 oC from the miscella is considered as the high grade neem oil because it is less reactive due to lowest percentage composition of polyunsaturated and can be stored for long time before usage. Furthermore, the results from this work will assist manufacturers in selecting the extraction temperature for particular application of the neem seed oil. The extracted oil is recommended for soap production due to its high saponification value.

Influence of Nitrogen-Modified Atmosphere Storage on Lipid Oxidation of Peanuts: From a Lipidomic Perspective.

The effect of nitrogen-modified atmosphere storage (NS) on peanut lipid oxidation was investigated in this paper. Non-targeted lipidomics was employed to detect the lipid metabolites in peanuts with the aim of exploring the mechanism of lipid oxidation in peanuts under different storage conditions. The results showed that compared with conventional storage (CS), NS significantly (p < 0.05) delayed the increase in acid value, carbonyl value, and 2-thiobarbituric acid value and the decrease in vitamin E content. However, the storage time has a much greater effect on lipid oxidation than the oxygen level in the storage environment. Lipidomics analysis revealed that there were significant differences in metabolite changes between CS and NS. NS reduced the decline of most glycerophospholipids by regulating lipid metabolism in peanuts. NS maintained higher levels of Diacylglycerol (DAG), sulfoquinovosyl diacylglycerol (SQDG), lysophophatidylcholine (LPC), lysophosphatidylethanolamine (LPE) and phosphatidylinositol (PI) compared to CS. This work provided a basis for the application of NS technology to peanut storage.

Effect of Storage Period on Acid Value and Sensory Attributes of Puffed Wheat Grains ‘Badyrak Vanilla’ and ‘Badyrak with Whey’

Abstract Puffed grains made from whole wheat, corn or rice grains are ready-to-eat breakfast cereals that do not require additional preparation. Two recipes for puffed grain coatings were developed in the previous studies. Sunflower oil was used in the coating, which may affect storage stability. Due to lipid hydrolysis, free fatty acids may be released, causing rancid off-flavour. The aim of this study was to determine the changes in the acid value of lipids and sensory attributes of sweet-coated puffed wheat grains ‘Badyrak vanilla’ (BV) and ‘Badyrak with whey’ (MC) depending on temperature during their eight-month storage. The products were packaged in metallised polypropylene pouches, 30 g each. The acid value was studied monthly at different storage temperatures (20 ± 2 °С and 4 ± 2 °С). In puffed wheat grain products, 65% of fatty acids are polyunsaturated, 25% monounsaturated, and 10% saturated. The high proportion of unsaturated fatty acids over saturated makes oil more susceptible to oxidation. Literature studies and sensory evaluation of puffed wheat grains allowed setting a limiting acid value at 4.0 mg KOH g−1 lipids. The increase in acid value was storage temperature dependent. Thus, the acid value exceeded the established limit in the fifth month for MC and the sixth month for BV when stored at 20 ± 2 °С. At the same time, noticeable changes in puffed wheat grain flavour were observed. The temperature coefficient (Q10) for MC was 2.0, whereas for BV it was 1.5, indicating that the acid value increase in MC was more affected by temperature than that in BV.

Quality attributes of large yellow croaker (Larimichthys crocea) during refrigerated storage as affected by theaflavins.

Large yellow croaker (Larimichthys crocea) is an economical marine fish in China. Theaflavins have antibacterial and antioxidant properties. However, there is a lack of its application in the large yellow croakers during refrigerated storage. This study investigated the effect of theaflavins on the quality large yellow croaker (Larimichthys crocea) during 12 days of storage at 4°C. The results showed that theaflavins treatment was able to inhibit microbial growth and reduce the production of total volatile basic nitrogen (TVB-N). Meanwhile, theaflavins were beneficial in reducing the unfolding of myofibrillar proteins, decreasing the degree of protein aggregation, and improving the stability of protein structure. Therefore, the degree of protein oxidation was lower in the theaflavin-treated group compared with untreated group. In addition, theaflavins treatment effectively inhibited the increase in acid value (AV), peroxide value (PV), and malonaldehyde (MDA) content due to the ability of scavenging free radical. The effect of theaflavin was positively correlated with the increase in concentration under refrigeration conditions. Therefore, this study suggests that theaflavins handling is an auspicious and valid method to extend the preservation of refrigerated large yellow croaker. Overall, adding theaflavins to large yellow croaker can be an effective method of quality preservation during refrigerated storage. This article is protected by copyright. All rights reserved.

Preparation and application of cinnamon-Litsea cubeba compound essential oil microcapsules for peanut kernel postharvest storage

This research developed a novel, efficient and safe antimildew for peanut kernel postharvest storage. The antimildew, cinnamon-Litsea cubeba compound essential oil (CLCEO) microcapsule (CLCEOM), was synthesized with CLCEO as core materials and β-cyclodextrin as wall materials. Fourier transform infrared spectroscopy and gas chromatography-mass spectrometry analyses indicated that major antifungal compounds of CLCEO were encapsulated in the cavity of β-cyclodextrin. The inhibition zone experiment showed that CLCEOM retained antifungal effect on Aspergillus spp. strains even after storage for 2 months at 4 ℃. Besides, CLCEOM reduced total number of fungal colonies, relative abundance of Aspergillus spp., and aflatoxin B1 content of peanut kernels, and had positive effect on slowing down the increase in acid value of peanut oil without causing any adverse effect on the viability and sensory properties during storage process. Overall, CLCEOM presented good preservative effects on peanut kernels, providing evidence for its potential use as antimildew for peanut storage.

Simultaneous Esterification and Transesterification of Neem Seed Oil Using Ferric Sulphate Doped With Poultry Droppings as a Bifunctional Catalyst

The use of organic waste materials conjugated with inorganic sources as a bifunctional catalyst for one-step biodiesel production is currently under-utilized. In this study, a bifunctional catalyst for biodiesel production was developed from poultry droppings doped with ferric sulphate (FSPD). Its catalytic activity was investigated in simultaneous esterification and transesterification of neem seed oil (NSO) using methanol. Response Surface Methodology was employed in modelling and optimizing the reaction conditions. The characterization of the catalyst was done using Scanning Electron Microscopy equipped with Energy-Dispersive X-ray Spectroscopy, Fourier Transform Infrared Spectroscopy and X-ray Diffractometer. Fe (46.08 wt. %), S (22.31 wt. %), and Ca (11.82 wt. %) were the major elements present in the FSPD and the other results revealed that it is bifunctionally active. A biodiesel yield of 97.21% and acid value (AV) of 0.5 mg KOH/g were obtained at the optimum conditions of 21:1 methanol/oil ratio, 5 wt. %, catalyst loading and reaction temperature of 65°C after 180 min. The biodiesel produced using FSPD catalyst meets both the ASTM D6751 and the EN 14214 biodiesel standards. Reusability investigation of the FSPD showed remarkable stability up to the third reuse cycle with a slight decrease in biodiesel yield and a corresponding increase in acid value from 97.21% to 90.05% and 0.5–0.81 mg KOH/g respectively. The utilization of FSPD as a bifunctional catalyst is significant for improving the biodiesel output of high FFA oil and overall biodiesel production time.

Carboxylic acids derived from triacylglycerols that contribute to the increase in acid value during the thermal oxidation of oils

Acid value (AV), is a widely used indicator of oil degradation that, by definition, measures the free fatty acids formed via the hydrolysis of triacyclglycerols. However, based on observations made in previous studies, we hypothesized that the oxidation of triacylglycerols leads to the formation of carboxylic acids with a glycerol backbone which are also calculated as AV. In this study, we aimed to identify such carboxylic acids and prove the above hypothesis. Heating a canola oil at 180 °C for 6 h without the addition of water resulted in an increase in AV from 0.054 to 0.241. However, the contribution of free fatty acids to this increase in AV was minimal; free fatty acid-derived AV before and after heating was 0.020 and 0.023, respectively. Then, via mass spectrometric analyses, we identified two 8-carboxy-octanoyl (azelaoyl) -triacylglycerols (i.e., dioleoyl-azelaoyl-glycerol and oleoyl-linoleoyl-azelaoyl-glycerol) in the heated oil. Azelaoyl-triacylglycerols-derived AV before and after heating the oil was 0.008 and 0.109, respectively, demonstrating that azelaoyl-triacylglycerols contribute to AV. Such an increase in AV by azelaoyl-triacylglycerols was also observed in an oil used to deep-fry potatoes (i.e., an oil with a relatively high water content). These results suggest that AV is also an indicator of the thermal oxidation of triacylglycerols.

Effect of rice bran rancidity on the structure and antioxidant properties of rice bran soluble dietary fiber

The effects of storage time of fresh rice bran on the structure and antioxidant properties of rice bran soluble dietary fiber (RBSDF) were investigated. As the storage time of rice bran prolonged, a significant increase of acid value of rice bran crude oil was accompanied by a significant decrease of RBSDF yield (P < 0.05). The antioxidant properties of RBSDF first increased, and then decreased, which was accompanied by the formation of oxidized aggregates of RBSDF. The results of FT-IR and monosaccharide composition implied that hydroxyl oxidation was accompanied by changes in monosaccharide composition of RBSDF during storage of rice bran. As the storage time of rice bran increased, the content of free phenolics gradually increased, the content of bound and total phenolics first increased, and then decreased. The results of correlation analysis showed that among the factors affecting the antioxidant properties of RBSDF, the content of phenolics and soluble aggregates was more significant than monosaccharide composition. Overall, the structure and antioxidant properties of RBSDF were related to the degree of rice bran rancidity, suggesting that the degree of rice bran rancidity could be one of the potential means to regulate the antioxidant properties of RBSDF.

Assessment of Quality Parameters in Edible Vegetable Oils

Objectives: Edible oils, derived from a plant source, play a vital role in providing nutrition. A quality edible oil has a flavor, range of physicochemical parameters. Several quality parameters like saponification value, acid value, peroxidase value and iodine value will be helpful in estimating the quality of edible vegetable oils. The present study was intended to evaluate the quality difference between cooked and uncooked oils. Materials and Methods: Utilizing various edible oil samples from major brands in india e.g sunflower oil, soybean oil, canola oil, almond oil, coconut oil and, olive oil saponification value and acid value was determined. All the oil samples were thoroughly characterized by calculating their saponification value and acid value using the standard procedure of association of official analytical chemist (AOCS) and American oil chemist society. Results: In comparision to uncooked oils, cooked oils had significantly higher sapnification values. The acid values were also increased in cooked oils compared to uncooked oils. Widely used sunflower oil had a two fold significant increase in saponification value and five fold significant increase in acid value after cooking. Similar changes were not observed in olive oil. Conclusion: Taken together, results of our study indicate that widely used sunflower oil might not be appropraiate for domestic usage. Further, our results also indicate that olive oil might be a better choice for domestic cooking. Further studies are required for a large scale validation of the present results there by brining in regulation/public health policy on usage of cooked oils by various small scale food vendors.

Effect the addition of micro- and nano-capsule cumin and clove oils as antioxidants and anti-cancer on rancidity and shelf life in some biscuit products

The natural properties of clove and cumin oil are well known especially as an antioxidant and anticancer, however, natural variations, thermal instability and low water solubility impose restrictions on harnessing its potential and its use in the food industry. The nano-encapsulates were prepared from clove and cumin oil separately to protect them from exposure high temperatures using natural carboxy-methyl-cellulose (CMC) coating. The results showed that the transmission electron microscopy (TEM) morphology had a particle size between 21 to 20.74 nm for clove oil capsules, while it was from 24.03 to 65.88 nm for cumin oil capsules and the DSC thermal stability of the cumin oil capsules was higher than that of clove oil 212.08 and 175.92 °C, respectively. Two types of biscuits were prepared (sweet and salt biscuits) by adding nano-encapsulates clove and cumin oil, respectively. The results of sensory evaluation showed a general acceptance of salted biscuit samples containing nano-encapsulate cumin oil, followed by sweet biscuit samples containing nano-encapsulate clove oil. The results of the anti-oxidant activity showed the highest activity nano-encapsulate of both oils, and the highest activity was clove oil coated with nano-encapsulate. During the storage stability of the biscuit samples at room temperature, the increase of acid value and peroxide value at room temperature was the least possible in the samples containing nano-encapsulate of clove oil, followed by that containing cumin oil in comparison with other samples. The anti-proliferative effect of clove oil nano-encapsulate in CMC was apparently equally strong with primary clove oil in PC3, HePG2 and MCF-7 cell lines compared to clove oil non-encapsulate.

PHYTO-CHEMICAL AND NUTRITIONAL PROFILING OF TENDU FRUIT (DIOSPYROS MELANOXYLON ROXB.) AND EVALUATION OF ITS SHELF STABILITY

Tendu fruit is one of the important forest fruit found in major part of India. Originally, plant is well known for its leaves as Bidipatta for making bidi in tribal areas of India. Since, the tendu fruit supposedly have very short shelf-life, therefore, the present study has been undertaken to evaluate the shelf stability as well as the nutritional and phytochemical potential of the fruit.The complete proximate analysis including the mineral and vitamin profiling of the pulp, skin and seeds were done. The fruit pulp was found to be especially rich in calcium, magnesium, sodium, potassium, phosphorous, thiamine, riboflavin, niacin and vitamin C, with potassium being as high as 305.52±8.94 mg/100 gm (wet basis) . The fruit skin was found to have high amounts of crude fibre, potassium, calcium, phosphorous&amp; magnesium, whereas for seeds, the values of protein, crude fibre and oil were 7.02±0.53 % 25.13±0.41 and 5.54±0.07 % respectively. The storage stability of the fresh fruit was found to be 5 days at 25°C and 65 % R.H. During storage, pH of fruit reduced drastically with an increase in acidity value from 0.12±0.00% to 2.09±0.01 %. The reading of Browning index (A420nm) also gradually increased from 0.2257 to 0.4766. The DPPH scavenging activity, Hydrogen peroxide scavenging activity,Hydroxyl radical scavenging activity, and Reducing power assay of fruits were observed to be very high. Gallic acid and Tannic acid content in fruits was reported as 28.43% and25.74 % respectively on dry basis.

Application of Oleogel and Conventional Fats for Ultrasound-assisted Obtaining of Vegan Creams.

The purpose of this study was to determine the impact of the fat system type (milk fat - MF, palm oil - PO or oleogel - OG, i.e. RO-LO - rapeseed oil and linseed oil mixture structured by candelilla wax) on the properties of soy creams, in comparison with dairy cream. The MF exhibited the most increase of acid value (2.5-fold), and the RO-LO - increase of peroxide value (3-fold), after 30 days of storage at 20°C. The PO was the most oxidative stable. The OG presented the slightest oxidative changes, the highest slip melting point (39°C) and centrifugal stability (99.6%). The pH and total acidity values of soy creams were similar to soy drink. All creams exhibited unimodal distribution of dispersed particles. The average particle size and dispersity indexes of these emulsions were in range of 1.74-1.80 µm and 0.93-1.16, respectively. The creams with MF or OG exhibited a greater viscosity than sweet dairy cream - 1.66 10-5 nm-2, and a higher degree of shear-thinning. The accelerated creaming phenomenon (flotation of lipids molecules) occurred during centrifugation. The cream with PO had the lowest resistance to centrifugal force (instability index - 0.052). The possibility to obtain a stable vegan soy creams containing oleogel (as replacer of conventional fats) has been demonstrated.

Use of ethanol extract of Chuanminshen Violaceum to inhibit the deterioration of frying oil

Influence of ethanol extract of Chuanminshen Violaceum (EEC) on the changes in physicochemical characteristics of soybean, rapeseed, and palm oils during frying was investigated. Composition analysis revealed that a total of 16 compounds with possible antioxidant activity were contained in the obtained EEC, such as bergaptol, curcumenol, viscutin, homobutein, nissolicarpin, and 4-hydroxyisopimpinellin. Similar to tert-butylhydroquinone (TBHQ), EEC inhibited the increases in acid value, carbonyl value, and total polar compound content of frying oil during frying. The decrease in content of polyunsaturated fatty acids and the increase in content of saturated fatty acids were also significantly inhibited in TBHQ-added or EEC-added oils. More than 45 % of the reduction in concentration of octanoic acid was obtained in EEC-added oils, which was comparable to those observed in TBHQ-added oils. Thermal oxidative degradation of polyunsaturated fatty acids was proven to be retarded by adding EEC and TBHQ to moderate the deterioration of frying oil. Thus, the potential use of EEC as a natural antioxidant was demonstrated to extend the usage life of vegetable oils with a high content of polyunsaturated fatty acids during frying.

Change pattern and correlation analysis of macroscopic characteristics, active components and rancidness degrees of Armeniacae Semen Amarum in deterioration process

To discuss the effect of deterioration on the quality of Armeniacae Semen Amarum by observing the changes of macroscopic characteristics, active components and rancidness degrees of Armeniacae Semen Amarum in deterioration process. The traditional macroscopic identification was used to observe, identify and classify the morphologic and organleptic characteristics of Armeniacae Semen Amarum. The contents of amygdalin and fatty oil(two representatives of active components) were detected by HPLC and general rule 0713 in Chinese Pharmacopoeia, respectively. Acid value and peroxide value of the samples were selected as the representative indices of different rancidness degrees, and the general rule 2303 was adopted as the method for quantitative analysis. Then principal component analysis(PCA), partial least square analysis discrimination analysis(PLS-DA) were further utilized to establish the discriminative models of samples with different rancidness degrees, and also to screen out the largest contribution factors. In sensory evaluation, Armeniacae Semen Amarum samples were divided into three groups: non-rancid, slightly-rancid, and noticeably-rancid. The color of seed coat, cotyledon and surface of noticeably-rancid samples was deepened, and the odor differed much from non-rancid samples. Average content of amygdalin and fatty oil in non-rancid samples was 4.12% and 67.77%, respectively, both meeting the requirements of Chinese Pharmacopoeia; and decreased to some extent in slightly-rancid samples. However, the content of amygdalin sharply dropped to 0.074% in noticeably-rancid samples. The acid value and peroxide value were increased significantly with the intensifying of the rancidness degree, from only 1.363 and 0.016 74 in non-rancid samples to 1.865 and 0.023 70 in slightly-rancid samples, even doubled in noticeably-rancid samples(2.167 and 0.033 82). The discriminative models established by PCA and PLS-DA could complete the task of distinguishing the non-rancid samples from noticeably-rancid ones. The contribution degree of amygdalin content as one of the input attributes of discriminative model was higher than 1. Rancidness affected the quality of Armeniacae Semen Amarum, resulting in appearance changes, decrease in content of active components, and increase in acid value and peroxide value. Obviously, noticeably-rancid samples were non-conforming to Chinese Pharmacopoeia and no longer suitable for medicinal use. Rancidness can significantly reduce the quality of Armeniacae Semen Amarum, and even could possibly produce toxicity, which should attach more attention.

진피가루 첨가 마들렌의 품질 특성 및 항산화성

This study was to investigate the antioxidant and quality characteristics of madeleine prepared by various the amount of (0%, 3%, 5%, 7% and 10%) Citrus mandarin peel powder added. Moisture was higher in the supplemented groups added with Citrus peel powder than the control groups. The pH was significantly decreased with addition of the peel powder. The L value of the chromaticity decreased significantly as the powder addition increased, and the a and b values tended to increase. The hardness was significantly difference with the increase in the amount of Citrus mandarin peel powder added. In addition, the elasticity, cohesion, chewiness, and testability were significantly decreased with the increase in the amount of peel powder. DPPH radical scavenging activity and total flavonoid content, the addition of Citrus mandarin peel powder increased significantly. The addition of Citrus mandarin peel powder in madeleine had a lower increase in acid values for three weeks. In sensory evaluation, madeleine with the peel powder showed high aroma, texture, softness and taste and the 3% added group had the highest preference score in overall.

Production and Quality Evaluation of Margarine from Blends of Melon and Palm Kernel Oils

The potential of margarine production from blends of melon and palm kernel oil was studied. Margarine samples were produced from composite oils containing 100:0, 80:20 and 70:30 melon seed oil and palm kernel oil, respectively. The physico-chemical composition, proximate properties and sensory evaluation were determined using standard methods. All data were subjected to statistical analysis at 5% level of significance. Proximate values increase for moisture (6.02-10.33%), ash (1.34-6.12%), crude fiber (4.27-6.99%) and carbohydrate (9.50-10.38%). Conversely, a decrease in protein and fat values was observed. Results for physico-chemical analyses showed a significant decrease in Iodine value (25.05-18.85) and peroxide value (0.44-0.32) with a remarkable increase in spread ratio (3.15-10.11%) and total soluble solids (45.32-75.46) but insignificant increase in acid value (1.84-2.30). Result for sensory evaluation showed that sample B had the highest score for all the sensory properties evaluated. However, it was not statistically different (P > 0.05) from sample C in terms of appearance, taste, aroma and mouth feel. Sample A with 100% melon oil and the blends (sample B and C) varied significantly (P < 0.05) in all the sensory properties investigated. It was concluded that the blend containing 70% melon oil and 30% palm kernel oil had the best potential for the production of margarine which would be acceptable.

Argon plasma effects on maize: pesticide degradation and quality changes.

During planting, storage and transportation of maize excessive amounts of pesticides are used to ensure production, resulting in pesticide residues on the maize that can threaten human health. Plasma, compared with other technologies, has been widely regarded as a green, safe and promising technology for surface decontamination to ensure maize safety and quality. The aim of this study is to discuss plasma effects on the degradation of chlorpyrifos and carbaryl on maize surface and the changes of treated maize quality. Results achieved the largest degradation efficiency of chlorpyrifos and carbaryl, up to 91.5% and 73.1%, respectively. The physical changes of maize were observed by scanning electron microscopy (SEM), showing a decrease in contact angle, an increase in surface free energy and polar component, leading to improved hydrophilicity of the treated maize. There was no significant change of vitamin B2 content of maize. A significant increase of acid value and decrease of moisture content and starch content were observed within acceptable limits. It is reasonable to believe that argon plasma treatment enhances the edible safety of maize while maintaining maize quality. © 2019 Society of Chemical Industry.

Influence of flour type on physico-chemical characteristics during deep frying.

The study focuses on understanding the influence of nutrients on frying oil degradation as well as its role in oil uptake by the fried substrate. Raw substrates were prepared taking refined wheat flour (rich in carbohydrate), soy flour (rich in protein) and gram flour (with both in a definite proportion) which were subjected to frying in sunflower oil at 185-200°C. Analysis of the fried oil, substrate and fried product was carried out. Increase in acid value with respect to the composition of the flour was not significant. Higher rate of oxidation and peroxide value were observed in the oil used for Gram flour snacks, which could be due to significant amounts of sodium and potassium salts. Fried oil with soy flour based snack showed higher total polar material% which could be due to accelerated oxidation. Oil absorption was promoted by starch and gluten and controlled by protein and insoluble fiber. Oil absorbed by refined-wheat flour and soy flour based snack were 30% and 9.33%. Gram flour-based snack absorbed 4.52% oil with superior oil quality comparatively.