Partial replacement of pork back-fat by vegetable oils in burger patties: effect on oxidative stability and texture and color changes during cooking and chilled storage

The present study was aimed to examine the impact of partial back-fat replacement (50%) by avocado (A), sunflower (S), and olive (O) oil on the chemical composition, oxidative stability, color, and texture of porcine burger patties (10% fat) subjected to oven cooking (170 °C/18 min) and chilling (+ 4 °C/15 d). The addition of vegetable oils caused a significant reduction of saturated fatty acids and a concomitant enrichment in unsaturated fatty acids. The incorporation of vegetable oils to porcine patties caused a significant reduction of TBARS formed as a result of cooking and the subsequent chilling. The usage of vegetable oils as back-fat replacers had no impact on the formation of protein carbonyls. Porcine patties with A- and O-patties displayed a more favorable ratio between volatiles contributing to rancidity and those contributing pleasant odor notes. Treated and control patties underwent similar discoloration during processing. The usage of vegetable oils and particularly, avocado and olive oils, as back-fat replacers, could be an interesting strategy to improve the nutritional and technological properties of porcine patties. PRACTICAL APPLICATION: The present study highlights the potential nutritional and technological benefits of replacing animal fat by vegetable oils in porcine patties subjected to cooking and chilling. The industrial application of vegetable oils in processed meat products would meet the current consumers' interest towards healthier food products. In addition, the usage of avocado oil would contribute to boost the avocado industry by providing an additional value to a by-product of great biological significance.     

Concentrations of medium-chain 2- and 3-hydroxy fatty acids in foodstuffs

Medium chain 2-hydroxy fatty acids and 3-hydroxy fatty acids (2-OH-FAs and 3-OH-FAs with 8–20 carbons) are widespread in nature but little was known about the quantities of these minor fatty acids in food. For this reason, the concentrations and composition of 2- and 3-OH-FAs in several foodstuffs (milk and dairy products, animal brains, suet, vegetable oils) and two non-food samples (wool wax and vernix caseosa) were determined by gas chromatography with electron-capture negative ion mass spectrometry in the selected ion monitoring mode. Lipids were isolated from samples by accelerated solvent extraction. After transesterification the obtained fatty acid methyl esters (FAMEs) were separated into OH-FAMEs and non-OH-FAMEs. The OH-FAMEs were converted into pentafluorobenzoyl (PFBO) derivatives (PFBO-O-FAMEs). 2- and 3-OH-FAs were detected in all samples analysed. Chain-length ranged from 8–20 carbons. In general, 3-OH-FAs dominated in milk and dairy products (maximum concentration 17.7 mg/100 g l.w. in goat milk) whereas 2-OH-FAs were more abundant in animal brains and suet. The lowest concentrations were determined in vegetable oils (0.21–2.42 mg/100 g l.w.) whereas the highest concentrations of 2-OH-FAs were determined in wool wax (1180 mg/100 g l.w.) and vernix caseosa (34.5 mg/100 g l.w.).     

Formation of trans fatty acids in edible oils during the frying and heating process

To assess an impact of heated edible oils on intake of trans fat, the formations of trans fatty acids (TFAs) in cooking conditions was estimated by a frying and heating model system. For the frying model, sliced raw potatoes (10% of the frying oil (w/w)) were fried in commercially available canola oil at 160, 180 and 200 °C, and the 10 frying cycles were performed. The TFAs contained both in fried potatoes and in frying oils were measured by gas chromatography (GC). Lipids content of raw potatoes was about 0.1% (w/w) and TFAs in the raw potatoes were negligible. On the other hand, fried potatoes contained lipids at the level of 8.8%–9.2% and their fatty acid composition was mostly in correspondence with that of the frying oil. The TFAs amount of potatoes fried by the tenth frying operation was at the level of 0.99–1.05 g/100 g lipids. When 100 g potatoes fried in this process were consumed, the TFAs intake was estimated at less than 0.1 g. After 10 frying operations, TFAs content, acid values and peroxide values of the frying oils were measured and compared with those of corresponding heated canola oils without food. The amounts of trans 18:1 FAs contained both in the frying oil and in heated oil were less than the quantitative limit (0.047 g/100 g oil). The increases of trans 18:2 FAs and trans 18:3 FAs of the used frying oil were 0.02 g/100 and 0.05 g/100 g, respectively, compared with those of the fresh oil. trans 18:2 FAs accumulation in the heated oil was slightly less than that in the frying oil. To elucidate TFAs accumulation in various edible oils during cooking, six kinds of commercially available edible vegetable oils were heated to 180 °C in glass test tubes. Small changes in TFAs amounts were observed after four hours heating. These results suggested that an ordinary frying process using unhydrogenated edible oils has little impact on TFAs intake from edible oils.     

Physicochemical properties and bioactive compounds of selected seed oils

The physicochemical properties and chemical composition of oil extracted from five varieties of plant seeds (bittermelon, Kalahari melon, kenaf, pumpkin and roselle seeds) were examined by established methods. The thermal properties of extracted oils by differential scanning calorimetry were also evaluated. Sensorial profiles of these seed oils were defined through the CieLab (L*, a*, b*) colour. Most of the quality indices and fatty acid compositions showed significant (P < 0.05) variations among the extracted oils. Physicochemical properties of the oils extracted were iodine value, 86.0-125.0 g I₂/100 g oil; saponification value, 171.0-190.7 mg of KOH/g of oil; acid value, 1.1-12.9 mg of KOH/g of oil, free fatty acid, 0.6-6.5 g/100 g of oil, and peroxide value 1.5-6.5 meq of O₂/kg of oil. Palmitic, oleic and linoleic acids were the major fatty acids in all of the extracted seed oils except for bittermelon, where eleostearic acid was the major fatty acid. Gallic, protocatechuic, p-hydroxybenzoic, vanillic, caffeic, syringic, p-coumaric and ferulic acids were identified in the extracted plant oils. Among these, vanillic acid was predominant in all extracted oils. The oils were rich in tocopherols with γ-tocopherol as the major components in all oil samples. Among the phytosterols, sitosterol was the major phytosterol extracted from the five plant seed oils. The seeds of these plants contain a great number of valuable minor compounds, which have a potential high value as food and for production of non-food products.     

Effect of cold press and soxhlet extraction systems on fatty acid,tocopherol contents,and phenolic compounds of various grape seed oils

In this study, fatty acids, tocopherol contents, and phenolic compounds of the grape seed oils obtained with cold‐pressed and soxhlet extraction systems from several grape seeds were investigated. Linoleic acid contents of cold‐pressed oils varied between 59.61 and 72.13%. In addition, linoleic acid contents of oils obtained with soxhlet system changed between 58.51 and 71.17%. While α‐tocotrienol contents of oil samples extracted with cold‐pressed change between 13.21 and 34.71 mg/100 g, α‐tocotrienol contents of oils obtained by soxhlet system in all grape varieties varied between 8.89 and 33.89 mg/100 g. In addition, while ?‐tocotrienol contents of cold‐pressed oils range from 15.47 to 39.95 mg/100 g, ?‐tocotrienol contents of soxhlet extraction oils in all grape varieties were determined between 13.47 and 35.75 mg/100 g. Both systems' oils are rich in catechin, gallic acid, and chlorogenic acid. While catechin contents of cold‐pressed oils change between 427.80 and 847.14 mg/kg, catechin contents of soxhlet extraction oils in all grape seeds ranged from 537.11 to 836.88 mg/kg.

Practical applications

Cold‐pressed grape seed oil stands out as a suitable alternative to other commonly used vegetable oils because of its higher amounts of essential fatty acid, and many others bioactive compounds. Grape seed oil is being used in various fields such as cosmetics and cooking. Because the cold‐pressing does not need both heat and chemical treatments, cold‐pressed oils are being preferred for natural and safe food products by consumer. The consumption of vegetable oils rather than solid fats is crucial to maintaining health. As known, grape seed oil is an environment friendly oil due to a by‐product of wine and grape juice‐making processes.     

Fatty acid composition,oxidative stability,antioxidant and antiproliferative properties of selected cold-pressed grape seed oils and flours

Cold-pressed chardonnay, muscadine, ruby red, and concord grape seed oils and their defatted flours were studied for their fatty acid composition, oxidative stability and antioxidant and antiproliferative activities. The phenolic profiles of the seed flours were also measured. The most abundant fatty acid in the oils was linoleic acid, ranging from 66.0 g/100 g of total fatty acids in ruby red seed oil to 75.3 g/100 g of total fatty acids in concord seed oil. The oils were also high in oleic acid and low in saturated fat. Ruby red grape seed oil recorded the highest oxidative stability index of 40 h under the accelerated conditions. Total phenolic content (TPC) was up to 100 times lower in the oils than in the flours. Lutein, zeaxanthin, cryptoxanthin, β-carotene, and α-tocopherol levels were also measured. DPPH radical-scavenging capacity ranged from 0.07 to 2.22 mmol trolox equivalents (TE)/g of oil and 11.8 to 15.0 mmol TE/g of flour. Oxidative stability of menhaden fish oil containing extracts of the seed flours was extended by up to 137%. HPLC analysis was conducted to determine the levels of free soluble, soluble conjugated and insoluble bound phenolics in the seed flours. The phenolic compounds analyzed included catechin, epicatechin, epicatechin gallate, quercetin, gallic acid, and procyanidins B1 and B2. Antiproliferative activity was tested against HT-29 colon cancer cells. All of the seed flours and muscadine seed oil registered significant (P < 0.05) inhibition of cancer cell growth. The results from this study demonstrate the potential of developing value-added uses for these seed oils and flours as dietary sources of natural antioxidants and antiproliferative agents for optimal health.     

Production and evaluation of some physicochemical parameters of peanut milk yoghurt

The peanut milk for yoghurt production was prepared by fortifying peanut milk (∼12 g/100 g total solids) with 4 g/100 g skimmed milk powder. The final product was subjected to physicochemical analysis using cow milk yoghurt (CMY) as a control throughout the study. Peanut milk yoghurt (PMY) had higher protein content, fat, water holding capacity and lower susceptibility to Syneresis than CMY. PMY had lower lactose level (1.73 g/100 ml) compared to CMY (4.93 g/100 ml). Generally both PMY and CMY had high mineral composition and contained high amounts of essential amino acids. PMY also contained a higher proportion of unsaturated fatty acids than saturated fatty acids as compared to CMY. Therefore, in terms of fatty acid composition, PMY could be considered to be more health promoting than CMY. Sensory evaluation revealed that though PMY had better sensory texture scores than CMY, its sensory appearance, flavor and overall acceptability scores were lower than those of CMY.     

Evaluation of the effects of selected phytochemicals on quality indices and sensorial properties of raw and cooked pork stored in different packaging systems

The effects of lutein (100, 200 μg/g muscle), sesamol (250, 500 μg/g muscle), ellagic acid (300, 600 μg/g muscle) and olive leaf extract (100, 200 μg/g muscle) on lipid oxidation (thiobarbituric acid-reactive substances TBARs), colour (CIE L∗, a∗, b∗), pH, texture profile analysis (TPA), water holding capacity (WHC), cooking losses and sensorial properties of fresh and cooked pork patties were investigated. Raw and cooked minced pork (M. longissimus thoracis et lumborum) containing added lutein, sesamol, ellagic acid or olive leaf extract were stored aerobically or in modified atmosphere packs (MAP) for up to 8 and 12 days, respectively. Lutein, sesamol, ellagic acid and olive leaf extract had no significant effect on microbial status, cook loss, pH or WHC. Lipid oxidation was reduced (P < 0.001) in raw and cooked pork patties stored in aerobic packs and in MAP following addition of sesamol, ellagic acid and olive leaf extract. Antioxidant effectiveness in raw and cooked patties was in the order: sesamol = ellagic acid > olive leaf extract > lutein. Lutein increased (P < 0.001) b∗ yellowness values in raw pork patties. Addition of lutein, sesamol, ellagic acid and olive leaf extract to pork had no detrimental effects on the organoleptic properties of cooked patties but altered (P < 0.05) instrumental textural attributes. Results highlight the potential of using natural functional ingredients in the development of functional pork products with enhanced quality and shelf-life.     

cis/trans-Isomerisation of triolein,trilinolein and trilinolenin induced by heat treatment

To estimate the trans-fatty acid production of edible oils during the frying process, 1.0 g of triolein, trilinolein and trilinolenin, as representative oils, were heated at 180 °C for a defined period. The amounts of trans-fatty acids in heated triacylglycerols were quantitatively determined by gas chromatography after methylation. It was revealed that heating induced cis to trans-isomerisation of unsaturated triacylglycerols, and that trans-fatty acid amounts increased gradually, depending on the heating period. For example, trans-isomer amounts in triolein, trilinolein and trilinolenin (per gram) were 5.8 mg, 3.1 mg and 6.5 mg, respectively, after 8 h incubation at 180 °C. At that time, the contents of polar compounds contained in the heated triolein, trilinolein and trilinolenin were 22%, 27% and 31%, respectively. When triolein was heated under a N₂ stream, neither trans-isomerisation nor polar compounds were detected. The addition of α-tocopherol (1.0%) to triolein significantly prevented not only lipid oxidation but also trans-isomerisation during heating. A commercially available vegetable oil was also heated under the same conditions as these model oils. Compared with the trans-isomerisation in model oils, the degree of trans-isomerisation in the edible oil was relatively low. Tocopherols in the oil would prevent not only lipid oxidation but also isomerisation. These results suggest that the geometric isomerisation of unsaturated fatty acids during heating accompanies lipid oxidation.     

Tocols in caneberry seed oils

The compositional analysis of tocols in oils extracted from Korean caneberry seeds was compared with commercial soybean, corn, olive, canola, perilla, and grape seed oils. The oils from caneberry seeds of six different species were extracted using either a chloroform–methanol–water system or hot hexane. Tocols from all of the oils were analysed using isocratic HPLC. The contents of total tocopherols in the caneberry seed oils were about 75–290 mg/100 g oil, whereas tocotrienols were not detected. γ-Tocopherol was the most abundant tocopherol (31.8–239 mg/100 g oil) in the caneberry seed oils, followed by α-tocopherol (7.6–58.2 mg/100 g oil). The contents of total tocols in soybean, corn, olive, canola, perilla, and grape seed oils were 99.9, 61.1, 28, 27, 45.4, and 52.2 mg/100 g oil, respectively. Total tocol content was higher in most of the caneberry seed oils including the refined ones than in the commercial vegetable oils.     

Composition and antioxidative activities of supercritical CO2-extracted oils from seeds and soft parts of northern berries

The present study investigated the composition and the antioxidative activities of oils from the seeds and the soft parts of a range of northern berries extracted by supercritical CO₂. The seed oils of the species of Rubus, Vaccinium, Empetrum, Fragaria and Hippophaë were rich in linoleic (18:2n-6, 34-55% of total fatty acids) and ??-linolenic (18:3n-3, 29-45% of total) acids with n-6:n-3 ratios of 1:1-1:2. The seed oils of the species Ribes contained, in addition to linoleic and ??-linolenic acids, ??-linolenic (18:3n-6) and stearidonic (18:3n-4) acids. In seed oils from European rowanberry (Sorbus aucuparia L.) and snowball berry (Viburnum opulus L.), linoleic and oleic (18:1n-9) acids together exceeded 90% of the total fatty acids. The sea buckthorn (SB) pulp oil had palmitoleic (16:1n-7), palmitic (16:0) and oleic acids as the major fatty acids. The SB pulp oil and snowball berry seed oil were rich in ??-tocopherol (120 and 110 mg/100 g oil, respectively), whereas raspberry seed oil contained a high level of ??-tocopherol (320 mg/100 g oil). Seed oils of cranberry (180 mg/100 g oil), Arctic cranberry (190 mg/100 g oil) and lingonberry (120 mg/100 g oil) are rich sources of ??-tocotrienol. The berry seed oils and the SB pulp oil showed varying peroxyl radical scavenging efficacies (300-2300 ??mol ??-tocopherol equivalent per 100 g oil) and inhibitory effects on perioxidation of microsomal lipids (250-1200 ??mol trolox equivalent per 100 g oil) in vitro. The peroxyl radical scavenging activity positively correlated with the total content of tocopherols and tocotrienols of the oils (r = 0.875, P = 0.001). The SB seed oil and pulp oil were active in scavenging superoxide anions produced by xanthine-xanthine oxidase system and inhibited Cu²⁺-induced LDL oxidation in vitro. The SB oils also protected purified DNA and rat liver homogenate from UV-induced DNA oxidation in vitro. The current research suggests potential of supercritical CO₂-extracted oils from northern berries as nutraceuticals and ingredients of functional foods.     

Effects of dietary sources of vegetable oils on performance of high-yielding lactating cows and conjugated linoleic acids in milk

This study was conducted to examine the effects of dietary supplementation with vegetable oils on performance of high-yielding lactating cows and conjugated linoleic acid (CLA) content in milk fat. Twelve lactating Holstein cows in early lactation (30 to 45 d postpartum) were used in a triple 4 × 4 Latin square design. In each period, the cows in each group were fed the same basal diet and received one of the following treatments: 1) control (without oil), 2) 500 g of cottonseed oil, 3) 500 g of soybean oil, and 4) 500 g of corn oil. Each experimental period lasted for 3 wk, with the first 2 wk used for adaptation to the diet. Supplementation with vegetable oils tended to increase milk yield, with the highest milk yield in the cottonseed oil group (35.0 kg/d), compared with the control (34.4 kg/d). Milk fat percentage was decreased, but there were few effects on percentage and yield of milk protein as well as milk fat yield. The cows fed added soybean oil produced milk with the highest content of trans-11 C_18:1 (23.8 mg/g of fat), which was twice that of the control (12.6 mg/g of fat). Content of cis-9, trans-11 CLA in milk fat increased from 3.5 mg/g in the control to 6.0, 7.1, and 10.3 mg/g for the cows fed oils from cottonseed, corn, and soybean, respectively. A significant linear relationship existed between trans-11 C_18:1 and cis-9, trans-11 CLA. Supplementation with oils doubled the content of total fatty acids in blood plasma, with little difference between different vegetable oil sources. Octadecenoic acid content was significantly higher in blood plasma of animals fed added oils from cottonseed and soybean than those fed with corn oil and control. The plasma trans-11 C_18:1 content was significantly higher in the oil-added animals than in control. Supplementation of vegetable oils tended to improve milk production of lactating cows, and the CLA content in milk fat was significantly increased. Soybean oil seemed to be the optimal source to increase CLA production.     

Relationship between the solubility,dosage and antioxidant capacity of carnosic acid in raw and cooked ground buffalo meat patties and chicken patties

Antioxidant capacity of oil soluble and water dispersible carnosic acid (CA) extracted from dried rosemary leaves using HPLC was evaluated at two different dosages (22.5 ppm vs 130 ppm) in raw and cooked ground buffalo meat patties and chicken patties. Irrespective of total phenolic content, CA extracts reduced (p < 0.05) the thiobarbituric acid reactive substances (TBARS) by 39%–47% and 37%–40% in cooked buffalo meat and chicken patties at lower dosage (22.5 ppm) relative to control samples. However, at higher dosage (130 ppm) the TBARS values were reduced (p < 0.05) by 86%–96% and 78%–87% in cooked buffalo meat and chicken patties compared to controls. The CA extracts were also effective in inhibiting (p < 0.05) peroxide value and free fatty acids in cooked buffalo meat and chicken patties. The CA extracts when used at higher dosage, were also effective in stabilizing raw buffalo meat color.     

Chemical changes in extra virgin olive oils from Slovenian Istra after thermal treatment

Changes in the physico-chemical parameters of extra virgin olive oils after heating for 142 h at 100 °C with an air flow 10 L/h were investigated. The experimental study was carried out on the two predominant olive cultivars in Slovenian Istra – cv. Istrska belica and cv. Leccino. The data obtained showed that oils from Istrska belica were more stable than those from Leccino. Peroxide values and spectrophotometric data showed higher amounts of oxidation products in oils from Leccino than in those from Istrska belica. After thermal treatment fatty acid composition was changed more in Leccino oils; particularly the amounts of polyunsaturated fatty acids dropped significantly, while α-tocopherol was completely depleted in all samples. The content of total biophenols decreased from 598 mg/kg to 241 mg/kg in Istrska belica oils and from 391 mg/kg to 176 mg/kg in Leccino oils. HPLC data showed that transformation of secoiridoid biophenols to the simple biophenols, tyrosol and hydroxytyrosol took place.     

Practical use of surimi-like material made from porcine longissimus dorsi muscle for the production of low-fat pork patties

This study evaluates the effect of replacing fat with surimi-like material (SLM) made from the porcine longissimus dorsi muscle on the physicochemical and sensory characteristics of pork patties. Pork patties were produced with different levels of fat and SLM using a commercial method. Pork patties produced with 20% SLM had the lowest fat content (1.76%, P < 0.001), and had a higher cooking yield (87.41 vs. 78.57%, P < 0.05) and less shrinkage (4.01 vs. 9.02%, P < 0.001) than patties produced with 20% back-fat (control). Moreover, patties produced with SLM exhibited more acceptable organoleptic characteristics, including tenderness (P < 0.01) and overall acceptability (P < 0.001), than full-fat control patties. These results indicated that SLM cannot only be used as a fat replacer, but that it also improves the physicochemical and sensory characteristics of low-fat pork patties.     

The effects of gender,age and region on macro- and micronutrient contents and fatty acid profiles in the muscles of roe deer and wild boar in Mecklenburg-Western Pomerania (Germany)

Samples of M. longissimus were collected from a total of 203 feral roe deer (n = 118) and wild boar (n = 85) in two regions of Mecklenburg-Western Pomerania (Germany). The muscle lipid saturated fatty acid proportions of roe deer and wild boar ranged between 33 and 49 g/100 g total fatty acids and 31 and 35 g/100 g total fatty acids, respectively. The total n − 3 PUFA proportions in roe deer muscle varied between 8.0 and 14 g/100 g fatty acids, and in wild boar muscle between 2.6 and 6.0 g/100 g fatty acids. The major vitamin E homologue, α-tocopherol, was determined to be between 5.8 and 13.1 mg/kg in roe deer muscles. Lower levels between 1.2 and 4.7 mg/kg were measured in wild boar muscles. The iron and zinc concentrations in roe deer and wild boar muscle ranged from 26.3 to 33.9 mg/kg and from 17.0 to 21.7 mg/kg, and from 13.6 to 39.3 mg/kg and 18.1 to 31.9 mg/kg, respectively.     

Effects of buffered vinegar and sodium dodecyl sulfate plus levulinic acid on Salmonella Typhimurium survival,shelf-life,and sensory characteristics of ground beef patties

The inclusion of two sources of buffered vinegar and sodium dodecyl sulfate plus levulinic acid were studied as interventions for Salmonella Typhimurium and for their effect on shelf-life and sensory characteristics of ground beef. For the Salmonella challenge, beef trimmings (80/20) were inoculated then treated with 2% (w/v) liquid buffered vinegar (LVIN), 2.5% (w/w) powdered buffered vinegar (PVIN), a solution containing 1.0% levulinic acid plus 0.1% sodium dodecyl sulfate (SDLA) at 10% (w/v), or had no intervention applied (CNT). The same trim source and production methods were followed during production of patties for shelf-life and sensory testing without inoculation. SDLA patties had the largest reduction (P < 0.05; 0.70 log CFU/g) of Salmonella. However, LVIN and PVIN had the least (P < 0.05) psychrotrophic growth. SDLA patties had more purge (P < 0.05) and lower (P < 0.05) subjective color scores. There were not large differences in sensory characteristics, except PVIN exhibited stronger off-flavor (P < 0.05).     

Fatty acid profile and stability of oil from the belly flaps of Nile perch (Lates niloticus)

Oil extracted from the belly flaps of Lake Victoria Nile perch (Lates niloticus) was evaluated for fatty acid composition, contents of vitamin A, β-carotene and α-tocopherol, and oxidative stability. The oil was found to contain substantial amount of palmitic, palmitoleic, stearic, oleic, docosapentaenoic and docosahexaenoic fatty acids (FAs) and had high vitamin A content (3.94 ± 0.02 to 5.90 ± 0.02 mg/100 g of oil). Docosahexaenoic acid (10.45 ± 0.38%), docosapentaenoic acid (5.30 ± 0.60%) and eicosapentaenoic acid (3.63 ± 0.05%) were the most dominant polyunsaturated fatty acids (PUFAs). Ratios of PUFAs to saturated FAs were in the range 0.68 ± 0.02 to 0.74 ± 0.03, while the ratio of total ω-3 FAs to total ω-6 FAs was 0.85 ± 0.02 to 0.95 ± 0.08. The oils showed exceptional resistance to accelerated oxidation at 65 °C probably because of its high content of β-carotene (2.93 ± 0.03 to 4.69 ± 0.01 mg/100 g of oil) and α-tocopherol (2.11 ± 0.03 to 11.4 ± 0.92 mg/100 g of oil). From the results, it can be concluded that Nile perch oil is a rich source of essential fatty acids and vitamin A.     

Effects of replacing pork backfat with emulsified vegetable oil on fatty acid composition and quality of UK-style sausages

Rapeseed and sunflower oil were used to replace pork backfat in UK-style sausages by incorporating the oils as pre-formed emulsions. Replacing the pork backfat emulsion with rapeseed emulsion at total fat content of about 12%, reduced total saturated fatty acid (SFA) composition from 38% to 14% (4.5 to 1.8 g/100 g), increased monounsaturated fatty acid (MUFA) composition from 45% to 59% and increased polyunsaturated fatty acid (PUFA) composition from 15% to 25%. Partial replacement of pork backfat with rapeseed at a fat content of about 20% reduced SFA from 38% to 24% (7.2 to 4.8 g/100 g). There were no significant differences in eating quality and overall liking other than slight differences in the attributes ‘firmness’ and ‘particle size’. Improvement in the fatty acid composition was achieved without adversely affecting colour shelf life or lipid oxidation. The study suggests that a substantial reduction in SFA can be achieved by incorporating ‘healthy’ oils in UK-style sausages without adversely affecting eating quality or shelf life.     

Healthier oils stabilized in konjac matrix as fat replacers in n − 3 PUFA enriched frankfurters

Nutritional, sensory and technological properties of frankfurters as affected by reformulation processes designed to reduce fat content and improve fatty acid profile were investigated. Healthier oils stabilized in oil in water emulsion or in konjac matrix gel were used as fat replacers. Results showed that improved fat content by the replacement of pork backfat with konjac gel and by the addition of healthier oils stabilized by various different systems, both resulted in products with very similar characteristics. From a nutritional standpoint, reformulated frankfurters with konjac gel and/or added a healthier oil combination may claim “reduced fat content” and/or “high omega 3 fatty acid content” according to European Regulation, since they could contain less than 30% of the fat in the reference product and more than 0.6 g of ALA/100 g and more than 80 mg of the sum of EPA plus DHA per 100 g, respectively. Chill storage over 40 days generally had little effect on the technological characteristics of frankfurters.