Terms Of Peroxide Value Research Articles

Development of chitosan based microencapsulated spray dried powder of tuna fish oil: oil load impact and oxidative stability

Abstract The impact of fish oil concentration on the oxidative stability of microcapsules through the spray drying process using chitosan and maltodextrin as wall material was studied. Emulsions were prepared with different Tuna fish oil (TFO) content (TFO-10%, TFO20%, TF030% TF0-40%) while wall material concentration was kept constant. Microencapsulated powder resulting from emulsion prepared with high fish oil load have high moisture content, wettability, total oil and low encapsulation efficiency, hygroscopicity and bulk tapped density. Oxidative stability was evaluated periodically by placing microcapsules at room temperature. Microcapsules prepared with TFO-10% presented high oxidative stability in terms of peroxide value (2.94±0.04) and anisidine value (1.54±0.02) after 30 days of storage. It was concluded that optimal amounts of fish oil for microencapsulation are 10% and 20% using chitosan and maltodextrin that extended its shelf life during study period.

Storage Stability and Degradation Kinetics of Phytonutrients of Red Palm-pressed Mesocarp Olein

Red palm-pressed mesocarp olein (PPMO) contains plenty of naturally occurring phytonutrients. However, the application of PPMO in food is limited due to the lack of scientific data. In the study, stability and degradation kinetics of carotenoid and vitamin E in PPMO under two storage temperature, 23°C (with and without light) and 35℃ (without light), for a period of twelve months were performed. Amber bottles were used for optimum protection against damaging UV light. Both temperature and light conditions significantly influenced the total carotenoid and vitamin E contents of PPMO, as well as oil quality in terms of peroxide value and anisidine value to a different extent. Correlation analysis showed that oil quality was significantly but negatively correlated with phytonutrients. In addition, both zero- and first-order kinetic models were able to describe the degradation kinetics of the phytonutrients in PPMO. Zero-order was the best fit with higher correlation coefficients (R2) for both carotenoid and vitamin E contents, except for carotenoid that was kept at 23°C whereby first-order displayed the best fit. The half-life of carotenoid and vitamin E in PPMO were 40.8 months and 21.6 months, respectively under the optimised storage condition (23°C in amber bottles). In conclusion, storage of PPMO at lower temperature and in light-limited environment could effectively lower its oxidation rate and degradation rate of carotenoid and vitamin E, postulating its shelf life to be prolonged.

Oxidative stability of marine phospholipids derived from large yellow croaker roe

Large yellow croaker roe phospholipids (LYCPLs) have various functions and high nutritional value, which are expected to be functional foods ingredients. The aim of this study is to investigate the oxidative stability of LYCPLs at different temperatures (100 °C, 140 °C and 180 °C) in terms of peroxide value (POV), thiobarbituric acid-reactive substances value (TBARS), acid value (AV) and fatty acids compositions of phospholipids. The volatile compounds were also identified and analyzed via headspace solid-phase microextraction-gas chromatography-mass spectroscopy (HS-SPME-GC-MS) and headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS). The results showed that the highest POV was 192.92, 133.70 and 121.25 meq/kg at 100 °C, 140 °C and 180 °C within 10–20 min, respectively, then fell along with the increment of heating time, while the highest TBARS was 6.38, 7.66 and 8.19 mg/kg at 30 min, respectively. The AV was increased, but monounsaturated fatty acid and polyunsaturated fatty acid content were decreased with the increment of temperatures. A total of 94 volatile compounds were identified, and the content of alkanes, aldehydes, and heterocyclic compounds were reasonably increased, while the aromatic compound and amide compound content were decreased when LYCPLs heated at 180 °C. The present research improves the comprehensive understanding of oxidative stability of marine phospholipids.

Oxidative stabilization, pigmentation, and photosensitization properties of curcumin in vanaspati fat system under accelerated oxidation and irradiation photooxidation conditions

This study aimed to evaluate antioxidant and pigmentation properties of curcumin in vanaspati fat over 30 days under accelerated oxidation (AOC) and irradiation photooxidation conditions (IPC). For this purpose, different concentrations of curcumin (0.05%, 0.10%, and 0.20%) were added to vanaspati and the oxidation stability of the fat was examined in terms of peroxide value, p-anisidine value, TOTOX value, carbonyl value, and induction period of oxidation at 110°C. Results of AOC revealed the favorable antioxidant effect of curcumin. The increasing trend of the oxidative parameters was significantly slowed down over time (p < .05). In contrast, curcumin showed prooxidant properties under IPC and its addition intensified the increasing trend of oxidation parameters. The Lovibond red color of vanaspati increased by 0.8 unit, after the addition of curcumin. Although curcumin can be considered a good natural antioxidant in fatty products under thermal conditions, it acts as a photosensitizer in light conditions. Novelty impact statement The vanaspati fat containing 0.20% curcumin showed better oxidative stability performance than the one containing 0.01% ascorbyl palmitate under accelerated oxidation (AOC) condition (p < .05). The curcumin acted as an antioxidant under thermal conditions and as a photosensitizer in vanaspati fat under light conditions. The color resulting from adding curcumin showed very high stability over time under AOC and irradiation photooxidation conditions.

Storage stability of almond paste fortified with almond skin as antioxidants

This study was designed to explore the potential of almond skin in improving the storage stability of almond paste. A concentration-dependent increase in phenolic content, and antioxidant potential, was observed for the skin-fortified samples. Skin fortification at 1.25%, 2.5%, 3.75%, and 5% level in pastes resulted in a corresponding increase in TPC by 114%, 311%, 445%, and 633% compared with control. Lipid oxidation was measured in terms of peroxide value, thiobarbituric acid (TBA) value, and free fatty acids content over a 28 days of storage at accelerated storage temperature (60°C). TBA value for the control was higher (0.013–0.194 mg malonaldehyde/kg) compared with that of fortified samples with values ranging from 0.011 to 0.183 mg malonaldehyde/kg, indicating a role of skin fortification in the prevention of oxidation. Almond skin at 5% effectively inhibited lipid oxidation throughout the entire storage. Therefore, almond skin supplementation could be effective in preventing the oxidation of fat-rich food products. Practical applications Almond skin (AS) is a low-value by-product in the almond-processing industry, which possesses an appreciable amount of health-benefiting phenolic compounds. The use of almond skins in foods could improve the nutrient value and storage stability due to the enhanced antioxidant potential. Almond paste, upon supplementation with almond skins, displays a better nutrient profile and sensory characteristics similar to the standard product, which provides clean label antioxidant options.

Comparative Study of Astaxanthin, Cholesterol, Fatty Acid Profiles, and Quality Indices Between Shrimp Oil Extracted From Hepatopancreas and Cephalothorax.

Shrimp oil from two different portions of Pacific white shrimp including cephalothorax and hepatopancreas was extracted using the mixture of hexane/isopropanol (1:1). The extracted oils from the cephalothorax (CPO) and hepatopancreas (HPO) were characterized for astaxanthin content, cholesterol levels, and fatty acid profiles. Nutrition indices of CPO and HPO were also compared. CPO had lower extraction yield (3.2 ± 0.1%, wet weight basis) than HPO (11.1 ± 0.5%, wet weight basis). High-performance liquid chromatography results indicated that the astaxanthin content in HPO was higher, compared to that of CPO. Nevertheless, the cholesterol level in HPO was 70% lower than that of CPO. Fatty acid profiles of HPO and CPO demonstrated that the polyunsaturated fatty acid (PUFA) content in HPO was higher than that of CPO. The amount of docosahexaenoic acid in the former was ~2 times higher than that of the latter. HPO contained 42.76 ± 0.36% PUFA, whereas PUFA content of CPO was 35.27 ± 0.19%. On the other hand, saturated fatty acids (SFA) were more pronounced in CPO (38.44 ± 0.26%) than HPO (30.82 ± 0.55%). Based on nutrition indices, namely, atherogenicity index, thrombogenicity index, hypocholesterolemic/hypercholesterolemic (h/H) ratio, and PUFA/SFA ratio, HPO possessed higher health benefit than CPO. The oxidation status of CPO and HPO measured in terms of peroxide value, thiobarbituric acid reactive substances, anisidine value, and conjugated dienes indicated that higher primary oxidation products were present in CPO, whereas HPO exhibited more secondary oxidation compounds. Fourier transform infrared spectra further substantiated the presence of oxidation products in CPO and HPO. Liquid chromatography-mass spectrometry identification showed the enhanced levels of phospholipids and glycolipids in the ethanolic fraction of CPO. Overall, HPO with a higher yield was more beneficial in terms of health benefits than CPO.

Inhibition of browning via aqueous gel solution of Aloe vera: a new method for preserving fresh fruits as a case study on fresh kernels of Persian walnut.

Aloe Vera (AV) gel is commonly used as a natural, inexpensive, edible coating that can improve the quality and shelf life of fruits. The objective of this study was to evaluate how two methods of applying AV, i.e. as an edible coating (dry environment) and as a gel solution (aqueous environment: a new method), prevent browning and maintain quality characteristics of fresh kernels of Persian walnut for 60days during cold storage. Distilled water was used as a control group for both environments. In general, AV caused a reduction in the peroxide value (POV) of kernels, while preserving Total Phenolic Compound and Total Antioxidant Activity (TAA). The AV treatment slowed down the process of color change and maintained sensory properties during storage, compared to the control groups of both methods. The AV gel solution performed better than the AV edible coating in terms of POV, color (L* and h°) and microbial growth. In contrast, the AV edible coating was more effective in preserving TPC and TAA. Also, TAA was found to have a significant, positive correlation with L* and, simultaneously, a negative correlation with POV. As far as we know, this is the first instance that the AV gel was used as a formulated solution and as an edible coating on fresh fruits. This innovative method can be used in commercial practice, while being ecofriendly and non-chemical as a treatment for the maintenance of postharvest quality in fruits.

Sensory and Physicochemical Quality Characteristics of Haddock Fish Cake Enriched with Atlantic Mackerel Quality of Fish Cakes.

SUMMARYResearch backgroundIt is desirable to increase the consumption of pelagic fish rich in long-chain omega-3 fatty acids. Partial replacement of traditionally used white fish species by pelagic fish will increase the content of omega-3 fatty acids, and thus improve the nutritional value but it may also affect the consumer acceptance. The aim of this study is to assess the physicochemical and sensory quality of novel fish cake prototypes prepared from haddock and mackerel mince.Experimental approachFillets of haddock and Atlantic mackerel were used as raw material for preparation of fish cakes. The fish fillets were minced, mixed together (in haddock/mackerel mass ratio of 100:0, 75:25 and 50:50%) with salt, potato starch, pepper and full fat milk. Physicochemical and sensory analyses were further performed.Results and conclusionsThe fatty acid composition analysis showed that the recommended daily intake of 250 mg of eicosapentaenoic acid and docosahexaenoic acid can easily be reached by consumption of fish cakes enriched with mackerel. The oxidation levels of all fish cakes were low in terms of peroxide value and thiobarbituric acid reactive substance assay (TBARS). Fish cakes prepared with higher mass fraction of mackerel mince (>50%) had significantly (p<0.05) softer texture than other fish cakes due to higher amount of fat in their formulations. At the same time, these fish cakes were significantly darker than haddock-based (>50%) fish cakes due to higher myoglobin content in the fish muscle. Moreover, fish cakes with higher amount of mackerel mince had increased yellowness due to the accumulation of water-soluble (r=0.990, p<0.05) and fat-soluble (r=0.976, p<0.05) TBARS. Metabolites relevant for taste and quality were quantified by using 1H nuclear magnetic resonance (NMR) spectroscopy. The mass fraction of anserine, trimethylamine oxide and β-alanine decreased, while the mass fraction of histidine, glutamic acid and alanine increased with the addition of mackerel. Sensory tests have shown the addition of mackerel did not reduce consumer acceptability towards the new fish cakes.Novelty and scientific contributionThe research demonstrated that Atlantic mackerel can be successfully used for partial replacement of white fish species in fish cake formulations to produce healthy and tasty ready-to-cook products and increase the consumption of small pelagic fish in Europe.

Walnut Meal Whitening and the Impact of Whitening Factors on Its Quality

Walnut meal is a nutrient-rich product and has a high nutritional value. Walnut meal is a product that can be used in food technology, in order to improve the nutritional quality, expand the range of confectionery products, and replaces the walnut kernel. Due to the dark color, the use of the walnut meal in the preparation of pastries would have a negative effect on the appearance of some final products and the whitening process would allow its use without negatively influencing the final product. The aim of the research is to whiten Juglans regial L. walnut meal as a valuable nutritious raw material. Hydrogen peroxide was used to bleach the walnut meal, and the pH, concentration of the whitening agent and the concentration of the meal were used as variable parameters of the bleaching process. The color descriptors (Whitening index, Saturation index, Total color difference, Browning index) were calculated to establish the optimal whitening conditions of the walnut meal. The obtained results showed that an alkaline medium, with the hydrogen peroxide concentration of 10% and 2.5% meal concentration allows obtaining the best color parameters in terms of Lightness (82.20) and Whitening Index (71.20). In addition, the study of walnut meal quality in terms of peroxide value evolution showed that the treatment with hydrogen peroxide does not affect in any way the value of the peroxide index of the lipids. The highest peroxide value (4.91 mmol/g oil) was recorded for the sample bleached in a 10% Hydrogen peroxide solution, with a pH of 10 against the 4.71 mmol/g oil for the unbleached sample.

Strategies to Improve the Thermo-Oxidative Stability of Sunflower Oil by Exploiting the Antioxidant Potential of Blueberries Processing Byproducts.

This research was conducted in order to establish the effectiveness of two freeze-dried extracts obtained from blueberry processing byproducts resulting from juice manufacturing compared to butylated hydroxytoluene (BHT) in delaying the lipid oxidation of sunflower oil subjected to high-temperature convective heating at 180 °C up to 12 h under simulated frying conditions. The fruits were harvested from spontaneous flora of two regions of Romania, Arieseni (Alba County) and Paltinis (Sibiu County) and the blueberry byproducts extracts (BBE) were noted according to the origin place as ABBE and PBBE. The progress of lipid thermo-oxidation was investigated in terms of peroxide value (PV), p-anisidine value (p-AV), the response of TBA-malondialdehyde interactions assessed by thiobarbituric acid (TBA) method, the total oxidation (TOTOX) value and inhibition of oil oxidation (IO). The recorded data highlighted that BBE exhibit a high inhibitory response on lipid thermo-oxidation. The inhibitory effect was concentration-dependent, thus, the degree of lipid oxidation was in reverse related to the BBE dose. The exposure of the oil samples supplemented with 800 ppm BBE (ABBE, PBBE) to a high-temperature heating for 12 h led to a significant decrease of the assessed indices compared to additives-free sunflower oil sample as follows: PV (46%; 45%), p-AV (21%; 17%), TOTOX (27%; 24%), TBA value (25%; 11%). Regarding the impact of the origin on the potential of BBE to inhibit the lipid oxidative degradation, it was noted that ABBE derived from blueberries grown in a region with a milder climate with moderate precipitations and higher temperatures showed a stronger inhibitory effect on lipid thermo-oxidation than PBBE. A moderate level of 500 ppm BBE inhibited the lipid oxidation similar to 200 ppm BHT. The reported results reveal that BBE represent efficient natural antioxidants that could be successfully applied to improve the thermo-oxidative stability of sunflower oil used in various high-temperature food applications.

Effect of low pressure cold plasma treatment on microbial decontamination and physicochemical properties of dried walnut kernels (Juglans regia L.)

AbstractIn this study, dried walnut kernels were processed by radiofrequency low pressure cold plasma (LPCP) treatment using normal air. Dried walnut kernels were treated with LPCP at different powers (20, 30, 40, and 50 W) and at different times (10, 15, and 20 min), and finally compared with the untreated sample. The tests performed in this study included microbial load reduction, decimal reduction time (D‐value), peroxide value, moisture content, texture firmness, and color parameters. The LPCP treated samples compared with the control sample significantly reduced the microbial load (p &lt; 0.05). The highest microbial log reduction was observed in 50 W for 20 min. Total viable count, coliform, and mold log reduction were equal to 1.09, 0.97, and 0.89 log CFU/g, respectively. D‐values were also calculated, with the maximum reduction observed at 50 W. The lowest D‐values for the total count, coliform, and mold were 19.66, 18.25, and 18.18 min, respectively. There was no significant difference between the treated and untreated samples in terms of peroxide value and firmness (p &gt; 0.05). However, the treated samples' moisture content diminished with increasing power and LPCP exposure time (p &lt; 0 .05). The result indicated that the LPCP darkened the treated samples' color.Practical ApplicationsThis study demonstrates the potential of low pressure cold plasma applications for the decontamination of dried walnut kernels. It is an appropriate alternative for product disinfection such as nuts, spices, aromatic plants, and other sensitive foods to high‐temperature processing, due to the lack of waste production, low energy consumption, low cost, and keeping the physicochemical properties of products intact.

Physico-chemical and quality characterization of pulp oil from two varieties of pili (Canarium ovatum Engl.) from Bicol, Philippines

This study aimed to characterize and compare pili (Canarium ovatum Engl.) pulp oil from two different varieties of pili fruits in Bicol, Philippines namely M. Orolfo and Orbase varieties for possible utilization into oil-based products. The effects of varietal differences in pili fruits on physical, chemical and quality characteristics of its pulp oil were determined. These two oils were also compared with control oils, commercially available coconut oil and extra virgin olive oil. Pili pulp oil from M. Orolfo had dark color while Orbase had color close to extra virgin olive oil. The two varieties did not significantly differ from each other in terms of refractive index, moisture and volatile matters, acid value, iodine value, saponification number and percent unsaponifiable matter but significantly differed from coconut oil and extra virgin olive oil. On the other hand, the two varieties significantly differed from each other in terms of peroxide value, Vitamin A and α-tocopherol contents. In terms of fatty acid profile, high amounts of palmitic acid were determined in both pili varieties (19-25%) compared with coconut oil (6.34%). Oleic acid in Orbase was 71.5% while M. Orolfo had 58.1%, which are comparable with extra virgin olive oil (77.9%). Pili pulp oils from M. Orolfo and Orbase can be utilized into oilbased products because its chemical and quality characteristics are within the standard. Both can be stored for a longer period of time and healthier in terms of fatty acid composition and natural antioxidant content.

Oxidative stability of cod liver oil in the presence of herring roe phospholipids

The aim of this research was to investigate the effect of herring roe phospholipids (PLs) on the oxidative stability of cod liver oil during storage. The effect of PLs on the oxidative stability of cod liver oil was assessed in terms of peroxide value, free fatty acids, secondary oxidation products and pyrrolisation. The results show that the PV was lower in cod liver oil containing PLs (P < 0.05) than in the control without PLs. Benzaldehyde, 2,5-dimethylpyrazine, 2-methyl-2-pentenal, 1-penten-3-ol and 3-methylbutanal were the main volatiles. In addition, significant pyrrolisation was observed after 28 days when PLs were added to cod liver oil. The results suggested that cod liver oil with dispersed PLs was oxidized during storage followed by non-enzymatic browning reactions. The findings indicated that the ratio between pyrroles formed and α-tocopherol may influence the formation of new peroxides and secondary oxidation products.

Edible vegetable oils enriched with carotenoids extracted from by-products of sea buckthorn (Hippophae rhamnoides ssp. sinensis): the investigation of some characteristic properties, oxidative stability and the effect on thermal behaviour

In the recent years, it has been granted a growing interest to the substitution of synthetic food antioxidants by natural ones, while a special attention was directed to their extraction from the by-products of the food industry. Sea buckthorn (Hippophae rhamnoides) by-products are promising sources of bioactive compounds that could be used for their favourable nutritional and functional properties. In this study, ultrasound-assisted extraction and maceration have been used for the direct enrichment of three edible oils (refined sunflower oil, cold-pressed sunflower oil and extra virgin olive oil) with carotenoids from dried sea buckthorn by-products. Total carotenoids content and ABTS free radical scavenger activity of both enriched and commercial oils were determined by spectrophotometric methods, and the colour was evaluated according to the CIELab colour space. The oxidative stability of vegetable oils containing the extracted carotenoids was assessed in terms of peroxide value, while the thermal stability of the oils was evaluated by thermogravimetry and by differential scanning calorimetry. It was shown that the ultrasound-assisted extraction was more effective than the maceration for the extraction of carotenoids from dried sea buckthorn by-products. ABTS radical scavenging activity has been slightly improved for all the oils studied after carotenoid enrichment, while the oxidative stability increased in extra virgin olive oil but decreased in unrefined and refined sunflower oils. Extraction of sea buckthorn by-products significantly (P < 0.05) reduced lightness and increased redness and yellowness of the oils.

Impact of Purslane (Portulaca oleracea L.) Leaves Extract to Enhance the Anti-oxidant Potential of Edible Oils during Heating.

The present work deals/ reveals with the effect of purslane leaves extract on the stability of soybean oil during heating and the acceptability of oil after preparation of poori (an Indian fried bread) by frying and its sensory evaluation. The ethanolic purslane leaves extract was blended with soybean oil at three different concentrations such as, 500, 1000 and 1500 ppm (T1, T2 and T3) and compared with control. The sample added with 100 ppm TBHQ was used as a positive control. Assessment of antioxidant activity of the ethanolic extract of purslane leaves was carried out by the estimation of total phenolic content, loss of β-carotene and antioxidant activity. The heating (173±2°C for 24 h; 8 h heating cycles per day) performance of soybean oil incorporated with purslane leaves extract was evaluated in terms of peroxide value, free fatty acid, total polar material and fatty acid composition. The thermal stability of the oils was evaluated using differential scanning calorimeter. The poori was prepared to check the acceptability of the oil. Results suggest that leaves extract of purslane (1500 ppm) may be used for obtaining reasonable thermal stability of soybean oil with acceptable sensory characteristics of the product. Although TBHQ showed almost similar thermal stability with leaves extract of purslane (1500 ppm), natural anti-oxidant is more preferred over synthetic anti-oxidant.

Active papers coated with chitosan and containing TiO2 and Ag/TiO2 nanoparticles for increasing the shelf-life of walnut kernels

Three active cellulose-based papers coated with chitosan (P–CH), chitosan–TiO2 nanocomposite (P–CH–TiO2) and chitosan–Ag/TiO2 nanocomposite (P–CH–Ag/TiO2), respectively, were subjected to real-time ageing for 6 months at 25 °C and 45% re humidity and characterized from a physical–chemical–antimicrobial perspective in relation to plain paper (P). Scanning electron microscopy pictures indicate a smooth morphology in the active papers, while the structure of P is rough with large pores. The fresh papers containing nanocomposites displayed enhanced barrier properties against water vapor, air and grease. The photocatalytic action of TiO2 during ageing results in the deacetylation of the chitosan layer and the degradation of cellulosic fibers with a reduction of barrier properties. Fresh P–CH–Ag/TiO2 displayed the highest value of inhibition index against yeasts and molds (95.65%), its value decreasing to 79.25% after 6-month storage. Walnut kernels were stored for 6 months at 25 °C and 45% RH in packages made of investigated papers and analyzed. It was found that P–CH–Ag/TiO2 is the most effective in the prolongation of the shelf-life of kernels. They are assessed to be safe in terms of peroxide value and yeasts and molds count for 11.6 and 15.1 months when stored in P–CH–Ag/TiO2 filled with 25 and 50 g kernels, respectively, as compared to 1.8 and 3.4 months, respectively when they are stored in P. The appearance of packages containing nanocomposites was clean without grease spots in opposition with that of P and P–CH and proves the self-cleaning property of P–CH–TiO2 and P–CH–Ag/TiO2. Cluster diagrams indicate a strong correlation between the quality and safety of kernels and properties of paper sheets in a paper type-depending manner.

Evaluation of commonly used herbs to enhance shelf life of ghee against oxidative deterioration

The study was conducted to evaluate potential of commonly used herbs as an antioxidant in ghee to extend the shelf-life by retarding oxidative reactions during its storage. Ghee samples were analysed for early-stage oxidative deterioration by peroxide value and flavor score in an accelerated storage study at intervals of 2 days till all the ghee samples became unacceptable in sensory evaluation. Among all the 14 types of herbs, betel leaves and curry leaves were found promising in retarding the oxidation as well as flavor deterioration of ghee during storage. Betel leaves had significant (p < .05) ability to enhance the antioxidant potential of ghee in terms of peroxide value, flavor score, and also retain their yellow color, whereas curry leaves had significant (p < .05) ability to enhance the antioxidant potential of ghee in terms of flavor score and retain their yellow color. Practical applications The development of rancidity in the ghee leads to formation of off-flavor and such an oxidized product is not accepted by the consumer; this leads to economic loss to the manufacturer. Betel leaves added ghee possesses good potential to act as an antioxidant/free radical scavenger and thus could help in prevention of many free radical related disorders. Standardized/Optimized curry leaves for appropriate stage and rate could also act as an antioxidant/free radical scavenger and help in prevention of many free radical related disorders. Addition of herbs in preparation of ghee offers health benefits to the consumers in addition to increase in stability of ghee against oxidative deterioration. These dual benefits of the herbal ghee help in improving the marketing prospects of the products.

Approaches Undertaken for Betterment of Stability and Acceptability of Cooking Soybean Oil

In the present study storage conditions ensuring better stability of Soybean oil over a period of 180 days were investigated. The study was carried out on 12 samples (4x3) of three brands namely brand A, B and C. After periodic interval of time ‘acid value’ and ‘peroxide value’ for each sample were determined. The result showed that in every case, darkness decreased degradation in oil over the normal condition over the period of experiments. Results were expressed in terms of acid value and peroxide value. For example peroxide values for samples of brand A stored under normal condition and in the dark were 0.88 on first day where the value came up to 128.64 and 33.3 at the end of 180 days respectively. The trend remained the same for the samples of brand B and brand C. In this study an attempt was made to decrease autooxidation in oils when vitamin E was added (1 ml of 200IU d-α-tocopherol per 100 ml of oil). Samples with and without vitamin E were stored under normal condition and in the dark. Results were expressed in terms of peroxide values. Results failed to show a clear trend of decreasing auto oxidation at the end of 180 days irrespective of the nature of storing condition.

Effect of gelatin/agar bilayer film incorporated with TiO2 nanoparticles as a UV absorbent on fish oil photooxidation

AbstractThis research evaluated the effect of gelatin/agar bilayer film and nanocomposites containing different concentrations of TiO2 nanoparticles (0.5%, 1% and 2%) as ultraviolet (UV) and oxygen barriers on the oxidative stability of fish oil. Samples of fish oil covered with the bilayer films were stored under UV light or in darkness and with or without lids at 18 °C for 12 days. Oil quality in terms of peroxide values (PV), thiobarbituric acid (TBA), conjugated diene (CD), fatty acids profile and colour change (∆E) was monitored during storage. Fish oil photooxidation was hindered by increasing TiO2 concentration, so that nanocomposite containing 2% of the nanoparticles could control photooxidation, similar to the samples stored in darkness. Furthermore, upon studying both photooxidation and autoxidation, the highest amounts of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), as well as the lowest amount of changes in PV, TBA, CD and ∆E, were observed in oils covered with the nanocomposites.

Antioxidant activity and sensory analysis of murtilla (&lt;em&gt;Ugni molinae&lt;/em&gt; Turcz.) fruit extracts in an oil model system

An oil model system was used to analyze the antioxidant activity of Chilean fruit extracts and to determine their odor sensory effect. Hydroalcoholic extracts from wild and 14-4 genotype murtilla (Ugni molinae Turcz.) fruit were assessed by the Response Surface Methodology. The optimal conditions for producing high total phenolic-content extracts were 49.5% (v/v) ethanol at 30 ºC, which yielded 18.39 and 26.14 mg GAE·g-1 dry matter, respectively. The optimized extracts were added to a lipid model system and evaluated via the Schaal Oven Test. After 96 hours, 150 and 200 mg·kg-1 oil of the wild and 14-4 genotype extracts, respectively, showed an antioxidant capacity similar to TBHQ (200 mg·kg-1 oil) in terms of peroxide values and odor. Thus, murtilla fruit extracts are a natural source of antioxidants for protecting lipidic foods, such as soybean oil.