Detection of adulteration by caprine body fat and mixtures of caprine body fat and groundnut oil in bovine and buffalo ghee using differential scanning calorimetry

Differential scanning calorimetry was used to detect adulteration of pure ghee with caprine body fat when added singly (at 5, 10 and 15%) and in combination with groundnut oil (GNO) (at 5, 10 and 15%). Samples were analysed for transition behaviour in terms of crystallising and melting curves. When compared to pure ghee, adulterated ghee samples showed a shift in the midrange temperature of thermal curves, indicating the presence of foreign fats. The results revealed that the detection of adulteration was possible at the lowest level of the study (5%), irrespective of the nature of the adulterants.     

Detection of the adulteration in pure cow ghee by electronic nose method (case study: sunflower oil and cow body fat)

Cow ghee is very used in some regions of Iran, such as Kermanshah province. Cow ghee is a natural source that contains high-quality nutrients which are needed for the human body. Adulteration in dairy products is not only a serious threat to human health but also it causes economic losses. Diagnosis of foodstuff cheating and its estimation is one of the key concerns in recent years. The aim of this study was the detection of the adulteration in cow ghee by olfactory machine system. Therefore, an electronic nose system was used for the different levels of sunflower oil and cow body fat mixed with pure cow ghee (10%, 20%, 30%, 40%, and 50%). The principal components analysis (PCA) and artificial neural networks (ANNs) methods were used to achieve this goal. Based on the results, the accuracy of the principal components analysis of sunflower oil and cow body fat were 96% and 97% of the data variance, respectively. According to the results, artificial neural networks identified the adulteration with sunflower oil and cow body fat with an accuracy of 91.3% and 82.5%, respectively.     

The Glycemic Potential of White and Red Rice Affected by Oil Type and Time of Addition

Limited research exists on how different oil types and time of addition affect starch digestibility of rice. This study aimed to assess the starch digestibility of white and red rice prepared with 2 oil types: vegetable oil (unsaturated fat) and ghee (clarified butter, saturated fat) added at 3 different time points during the cooking process (“before”: frying raw rice in oil before boiling, “during”: adding oil during boiling, and “after”: stir‐frying cooked rice in oil). Red rice produced a slower digestion rate than white rice. White rice digestibility was not affected by oil type, but was affected by addition time of oil. Adding oil “after” (stir‐frying) to white or red rice resulted in higher slowly digestible starch. Red rice cooked using ghee showed the lowest amount of glucose release during in vitro digestion. The addition of ghee “during” (that is boiling with ghee) or “before” (that is frying rice raw with ghee then boiling) cooking showed potential for attenuating the postprandial glycemic response and increasing resistant starch content. This is the first report to show healthier ways of preparing rice. White rice with oil added “after” (stir‐fried) may provide a source of sustained glucose and stabilize blood glucose levels. Boiling red rice with ghee or cooking red rice with ghee pilaf‐style may provide beneficial effects on postprandial blood glucose and insulin concentrations, and improve colonic health. The encouraging results of the present study justify extending it to an in vivo investigation to conclusively determine the effect of time of addition of fat when rice is cooked on blood glucose homeostasis.     

Feeding a concentrate rich in rapeseed oil improves fatty acid composition and flavor in Norwegian goat milk

Impaired quality due to a high content of free fatty acids (FFA) and off-flavors has caused challenges in the development of Norwegian goat milk products. The present study aimed to examine the effect of lipid-supplemented concentrates on milk fat content, fatty acid composition, FFA, lipoprotein lipase activity, sensory properties, and size of milk fat globules of goat milk. Thirty goats assigned to 3 experimental groups were fed different concentrates from 60 d in milk (DIM) until late lactation (230 DIM). The diets were (1) control concentrate (no added fat); (2) control concentrate with 8% (added on air-dry basis) hydrogenated palm oil enriched with palmitic acid (POFA); and (3) control concentrate with 8% (added on air-dry basis) rapeseed oil (RSO). The POFA group produced milk with the highest fat content, and fat content was positively correlated with the mean size of milk fat globules. Goats in the RSO group had a higher content of long-chain and unsaturated fatty acids, whereas milk from goats in the POFA group had a higher content of palmitic and palmitoleic acids (C16:0 and C16:1 cis). The control group produced milk with a higher content of short-, medium-, odd-, and branched-chain fatty acids compared with the 2 other groups. The content of FFA in milk was low in early and late lactation and peaked in mid lactation (90 DIM). A high content of FFA was correlated with poor sensory properties (tart/rancid flavor). The RSO group produced milk with lower content of FFA and off-flavors in mid lactation and a higher proportion of unsaturated fatty acids. Therefore, replacement of palm oil with rapeseed oil as a lipid source in dairy goat feed would be favorable.     

Apparent solidification time test for detection of foreign oils and fats adulterated in clarified milk fat, as affected by season and storage

An apparent solidification time (AST) test was developed for the detection of foreign fats and oils in milk fat. AST values at 18°C for buffalo and cow milk fats ranged from 2 min 30 s to 2 min 48 s and 2 min 56 s to 3 min 26 s, while for pig body fat, goat body fat and hydrogenated vegetable oils, AST values were 1 min 30 s, 0 min 40 s and 1 min 50 s, respectively. Vegetable oils yielded no AST values, suggesting that adulteration can be detected using the AST method in the case of some but not all possible adulterants.     

EFFECT OF DIFFERENT FATS ON THE QUALITY OF GOAT MEAT PATTIES INCORPORATED WITH FULL-FAT SOY PASTE

Effect of different fats such as goat fat, chicken fat, combination of goat and chicken fat and refined mustard oil (RMO) were evaluated in goat meat patties (GMPs). Patties with 10% RMO contributed significantly ( P <  0.05) better emulsion stability compared with others. There were no significant effects of different fats on physicochemical and textural attributes of patties. Patties with RMO had significantly ( P <  0.05) lower cholesterol content than other groups. GMPs with RMO, chicken fat and chicken and goat fat combination rated higher for all sensory attributes than patties with goat fat, which had significantly ( P <  0.05) higher mouth coating and lower overall acceptability. Flavor and overall acceptability were higher in patties with chicken fat. Histological study showed improper dispersion of goat fat in continuous phase of meat protein matrix (emulsion) compared with others .

PRACTICAL APPLICATIONS

Utilization of hard fats from goat, sheep and buffalo in emulsion-based meat products decreases emulsion stability because of its poor dispersibility, and consequently its cooking yield. Goat fat also contributes to a smeary and greasy mouth-coating problem and reduces the palatability of meat products. Alternatively, chicken fat disperses well in meat emulsion because of its high unsaturation and enhances the flavor of the products. However, the efficient utilization of goat fat is essential to support an economical goat meat production system and for developing meat products. The present study showed successful utilization of goat fat when combined with chicken fat, and the products had similar sensory attributes and acceptability as in meat products with chicken fat and refined mustard oil. This study would also help in better use of excess fat from spent hens in other meat products.     

Conjugated linoleic acid content of milk from buffaloes fed a mustard oil-based diet

Fifteen Murrah buffaloes were distributed in groups I, II and III. The group I animals were fed with groundnut cake-based concentrate, group II animals with mustard cake-based concentrate and group III with 2% of mustard oil added to the group II feed. Conjugated linoleic acid (CLA) estimation in milk was done by using GC. The average total CLA contents (mg/g milk fat) in the three groups were 6.84, 12.12 and 19.50 mg/g of fat respectively. Hence it was concluded that addition of 2% mustard oil resulted in a 185% increase in milk fat total CLA content.     

Nontargeted,Rapid Screening of Extra Virgin Olive Oil Products for Authenticity Using Near‐Infrared Spectroscopy in Combination with Conformity Index and Multivariate Statistical Analyses

A rapid tool for evaluating authenticity was developed and applied to the screening of extra virgin olive oil (EVOO) retail products by using Fourier‐transform near infrared (FT‐NIR) spectroscopy in combination with univariate and multivariate data analysis methods. Using disposable glass tubes, spectra for 62 reference EVOO, 10 edible oil adulterants, 20 blends consisting of EVOO spiked with adulterants, 88 retail EVOO products and other test samples were rapidly measured in the transmission mode without any sample preparation. The univariate conformity index (CI) and the multivariate supervised soft independent modeling of class analogy (SIMCA) classification tool were used to analyze the various olive oil products which were tested for authenticity against a library of reference EVOO. Better discrimination between the authentic EVOO and some commercial EVOO products was observed with SIMCA than with CI analysis. Approximately 61% of all EVOO commercial products were flagged by SIMCA analysis, suggesting that further analysis be performed to identify quality issues and/or potential adulterants. Due to its simplicity and speed, FT‐NIR spectroscopy in combination with multivariate data analysis can be used as a complementary tool to conventional official methods of analysis to rapidly flag EVOO products that may not belong to the class of authentic EVOO.     

Feeding of palm oil fatty acids or rapeseed oil throughout lactation: Effects on energy status,body composition,and milk production in Norwegian dairy goats

The objective of this experiment was to examine how supplements of rapeseed oil or palm oil fatty acids would affect milk production and composition, body lipid stores, and energy balance in 30 multiparous goats of Norwegian dairy goat breed. The experiment lasted 230 d, with 1 to 120 d in milk (DIM) for indoor feeding (P1), 120 to 200 DIM for mountain grazing (P2), and 200 to 230 DIM for indoor feeding (P3). Grass silage was fed according to appetite during indoor feeding periods. After an adjustment period (1–60 DIM) when the control diet was given to the goats, the animals were subdivided into 3 groups of 10 goats. Treatments (60–230 DIM) were (1) basal concentrate (control; no added fat); (2) control concentrate with 8% (added on air-dry basis) hydrogenated palm oil enriched with palmitic acid (POFA); and (3) control concentrate with 8% (added on air-dry basis) rapeseed oil (RSO). Individual energy balances based on energy intake and milk production were estimated on 10, 30, 60, 90, 120, 200, and 230 DIM. At the same times, body weight (BW), body condition score (BCS), body mass index, and body tissue stores using computed tomography were monitored. Silage intake was depressed by POFA throughout the experimental period. Reduced BW and body mass index were observed in the POFA and RSO groups, whereas no effect on BCS or body composition was observed throughout lactation. Generally, a minor decrease in BW was observed from 10 to 120 DIM (only 0.6 kg on average) and the total amount of body lipid was reduced by 4.4 kg. During the mountain grazing period, a further reduction in body lipid stores (2.7 kg) was observed, and BW was reduced by 3.9 kg in the same period. The goats mobilized, on average, 72% of their fat reserves during the first 200 DIM. In this period, dietary fat supplementation did not reduce the mobilization of adipose tissue but resulted in greater milk fat yield (2 kg more, on average, compared with the control group). Milk yield was not affected by POFA or RSO supplementation. Milk fat content was higher in the POFA group than in the control and RSO groups. Milk protein and lactose contents were not affected by lipid supplements. In late lactation, a rapid accumulation of fat deposits followed the intense mobilization during the grazing period. Dietary lipid supplements had no effect on milk fat yield at this stage. Milk production depends heavily on the ability to mobilize body lipid stores, and neither POFA nor RSO supplements at rates used in our study affected this mobilization.     

我国市售婴儿配方乳粉油脂配料使用情况分析

目的:了解我国市售婴儿配方乳粉的油脂配料使用情况及脂肪酸提供情况,为提升婴儿配方乳粉的营养水平及制定产品相关标准提供参考。方法:多渠道收集婴儿配方乳粉标签信息,统计分析油脂配料的种类、组合、最高添加量构成比及标识含量,比较全脂乳产品与脱脂乳产品、牛乳基产品与羊乳基产品、高必需脂肪酸产品与全部产品间的差异。均数和率的比较分别采用t检验和卡方检验。结果:共纳入269个婴儿配方乳粉。配料表分析显示,85%的产品使用了4种及以上的油脂配料,葵花籽油和椰子油在全部产品中的添加率最高,分别为88%、76%。牛、羊乳基配方粉的油脂配料使用情况存在差异,牛乳基配方粉中脂肪、亚油酸及α-亚麻酸的标识含量略高于羊乳基配方粉(P<0.05)。脱脂乳配方粉中,棕榈油添加率为32%,显著高于全脂乳产品(P<0.05)。44例使用了棕榈油的产品中仅有4例强化了1,3-二油酸2-棕榈酸甘油三酯。结论:牛、羊乳基配方粉中的必需脂肪酸标识含量基本一致。现市售婴儿配方乳粉以多种油脂组合使用的方式,以尽可能模拟母乳脂肪酸模式,但有些油脂类原料使用的科学性还有待进一步研究。     

Effect of antioxidant principles isolated from mango (Mangifera indica L) seed kernels on oxidative stability of buffalo ghee (butter‐fat)

A method was developed to extract and isolate the antioxidant principles, ie mainly phenolic and phospholipid classes, from mango (Mangifera indica L) seed kernels using organic solvents. The presence of at least six phenolic compounds and eight phospholipids in the isolates was confirmed by chromatographic techniques. A phenolic preparation and a phospholipid preparation were prepared separately by dissolving the isolated compounds from mango seed kernels in buffalo ghee. The phenolic preparation contained 9.6 mg% water‐extractable phenolics, 69.5 mg% total phenolics and 6.39 mg% phospholipids. The phospholipid preparation contained 155.8 mg% phospholipids, 0.11 mg% water‐extractable phenolics and 0.19 mg% total phenolics. The addition of these preparations to buffalo ghee at 5, 10 and 20% levels individually and in combination significantly increased the levels of phenolics and phospholipids respectively. Samples of buffalo ghee with added BHA contained levels of these compounds similar to that of a control sample without any other additives. The antioxidant indices calculated from the induction period of ghee samples stored at 80 ± 2 °C. in comparison with the control were, in order, 10.11 (20% phospholipid and phenolic preparation) > 8.88 (10% phospholipid and phenolic preparation) > 8.66 (20% phenolic preparation) > 6.44 (5% phospholipid and phenolic preparation) > 5.44 (10% phenolic preparation) > 4.88 (20% phospholipid preparation) > 3.00 (5% phenolic preparation) > 2.77 (10% phospholipid preparation) > 2.22 (5% phospholipid preparation) > 1.44 (0.02% BHA). This demonstrated that the phenolics and phospholipids isolated from mango seed kernel, when added jointly to buffalo ghee, helped in extending the shelf‐life of ghee. © 2000 Society of Chemical Industry     

Confirmation of buffalo tallow in anhydrous cow milk fat using gas liquid chromatography in tandem with species‐specific polymerase chain reaction

Confirmation of buffalo tallow in anhydrous cow milk fat (cow ghee) is a major problem to date. In the present investigation, a novel strategy has been developed to detect and confirm the buffalo tallow in cow ghee. It involved coupling the gas liquid chromatography (GLC) of triglycerides with the rapid species‐specific polymerase chain reaction (PCR) to confirm the presence of buffalo tallow in anhydrous cow milk fat. Adulteration of cow ghee with buffalo tallow at 10% level could be confirmed using the standardised protocol. The standardised protocol can help in countering the cases of cow ghee adulteration with buffalo tallow.     

Detection of possible adulteration in commercial ghee samples using low‐resolution gas chromatography triglyceride profiles

Fifteen commercial and 22 control samples of ghee were analysed for triglyceride compositions by low‐resolution short capillary column gas chromatography. Control samples of mixed milk and buffalo milks exhibited maxima at C38 and C50. The detection level was found to be 2% in case of beef tallow and coconut oil addition. Vegetable fat and lard addition could be detected at 5% and 6.3%, respectively. A sample survey based on triglyceride profile and standardised (S) values calculation revealed up to 43% branded ghee samples and 87.5% samples of unbranded ghee did not conform to triglyceride profiles of control ghee.     

Effect of oil content and processing conditions on the thermal behaviour and physicochemical stability of oil-in-water emulsions

The destabilisation mechanism of oil-in-water (o/w) emulsions was studied as a function of oil content (20% and 40% o/w), homogenisation conditions and crystallisation temperatures (10, 5, 0, −5 and −10 °C). A mixture of anhydrous milk fat and soya bean oil was used as the lipid phase and whey protein isolate (2 wt%) as emulsifier. Crystallisation and melting behaviours were analysed using differential scanning calorimetry. Physicochemical stability was measured with a vertical scan macroscopic analyser. Emulsions with 20% oil were found to be less stable than those with 40% oil. For 20% o/w emulsions, the crystallisation was delayed and inhibited in emulsions with smaller droplets and promoted in emulsions with larger droplets when compared with 40% o/w emulsions. Depending on the droplet sizes in the emulsion, the formation of lipid crystals (in combination with the emulsifier) either stabilises (small droplets) or destabilises (big droplets) the emulsion.     

基于近红外光谱的藏区酥油脂肪和蛋白质含量快速检测分析

为了建立藏区酥油中脂肪和蛋白质含量快速检测方法,以藏区不同产地酥油为研究对象,采用组合区间偏最小二乘法优选出脂肪和蛋白质的红外光谱特征波段,在此基础上分别对几种光谱预处理方法进行比较挑选出最佳预处理方法,最后建立脂肪和蛋白质的定量分析模型并对模型进行外部验证。结果表明:在脂肪和蛋白质的特征波段内采用SNV+数据归一化+二阶导数+S-G滤波法对光谱预处理后建立脂肪和蛋白质定量模型,模型相关系数(R)分别为0.994和0.997,交叉验证均方差(RMSECV)分别为4.09%和0.286%。对验证样本的预测值和实测值进行配对t检验,两种测量值之间没有显著性差异(P0.05),表明建立的脂肪和蛋白质的近红外定量模型具有良好的预测能力,基于近红外光谱快速测定藏区酥油中脂肪和蛋白质的含量是可行的。     

Feeding differently processed soya bean. Part 1. Effect on performance, protein utilization, relative organ weights, carcass traits and economics of producing broiler-chickens.

The comparative utilization of differently processed (roasted, cooked and oil cake) soya bean base diets and groundnut cake diet were evaluated in a feeding trial using 100 day-old Anak broiler-chicks. The response criteria included performance, protein utilization, relative organ weights, carcass traits and economy of production. At the end of the feeding trial, the average weight gains of chicks fed processed soya bean diets were significantly (P less than 0.05) higher than those fed groundnut cake and raw soya bean diets. Both feed consumption and efficiency were significantly (P less than 0.05) enhanced by processing. For example, feed consumption was highest in the chicks fed soya bean oil cake and least in those fed raw bean. Feed efficiency was best in chicks fed roasted soya bean. The relative weights [g/100 g body wt.] of the liver, kidneys, lungs, heart, gizzard and bursa were not significantly affected by the differently processed soya bean while the raw bean (unprocessed) significantly (P less than 0.01) increased pancreas weight. The dressed weight [%], eviscerated weight [%] and the relative weight of the thigh, drumsticks, chest, back and head were not significantly influenced by the dietary treatments. However, the relative weights of the shank and belly fat were significantly (P less than 0.05) affected. Cost-benefit analysis showed that the processed soya bean gave higher profit than groundnut cake diet. Among the soya bean diets, profit was in the order: roasted greater than cooked greater than oil cake greater than raw bean.     

Effects of feeding diets containing different fat supplements to swine on the visual properties and storage stability of low-fat sausage

Sixty barrows and gilts were assigned to one of five dietary treatments consisting of a control diet of corn and soybean meal and four similar test diets that contained a 10% replacement of either animal fat, safflower oil, sunflower oil or canola oil, to determine the effects of high levels of oleic acid in the diet of swine on the storage stability of fresh pork sausage. Pork trim from each treatment was used to formulate sausage that contained two fat levels (25% and 35%), and two levels of added water (3% and 11%). Thiobarbituric acid values did not differ between the control, safflower oil or sunflower oil treatments and all treatments were acceptable after 10 weeks of storage. Microbial numbers increased with the level of added water and during time in storage (up to 3 weeks). Visual evaluation showed that the control was the most red and least discolored, while the canola oil treatment was the least red and the most discolored. Results from the present study suggest that a 105 replacement of a typical corn/soybean meal diet to swine with safflower or sunflower oil did not alter the storage-stability of fresh pork sausage.     

Flavor release from salad dressing varying in fat and garlic flavor

Nine Ranch salad dressing samples varying in added canola oil (0, 6.75 and 13.5% w/v) and resoleum garlic (0.12, 0.36 and 0.6% w/v) were evaluated for garlic, pepper and sourness intensities by time–intensity profiling. Increased fat caused lower maximum intensity, total duration and area under the TI curve of garlic and pepper flavors (but not duration), and delayed sourness perception. Both molecular interactions between flavors and the food matrix, and physical properties of the food matrix may account for these effects of fat on flavor release.     

酶法预处理对花生油脂体稳定性的影响及酶法破乳工艺优化

为了提高花生油脂体的破乳率,采用复合植物水解酶提取花生油脂体,并在研究花生烘烤温度及粉碎时间对花生油体稳定性影响的基础上,利用响应面法对花生油脂体进行破乳条件的优化。结果表明:在粉碎时间为10 s时所得到的花生油脂体的粒径最大,继续增加粉碎时间则油脂体的粒径呈现出逐渐减小的趋势;此外,随着烘烤温度的增加油脂体粒径呈现出显著增加的趋势(p<0.05)且粒径分布由双峰逐渐过渡为单峰状态。通过响应面优化试验得到木瓜蛋白酶破乳的最佳条件为:酶解温度58 ℃,料液比为1:3 (w/v),酶浓度为1400 U/g,酶解时间为3 h,在此条件下花生油脂体的破乳率为93.44%±0.82%。优化后的木瓜蛋白酶破乳工艺清油得率较高,安全可靠,具有一定的应用价值。     

牦牛酥油微胶囊的制备及特性分析

为提高传统牦牛酥油的贮藏稳定性和生物利用率，本实验以海藻酸钠、CaCl₂为复合壁材，以锐孔法制备牦牛酥油微胶囊。以包埋率为指标，通过单因素实验和正交试验确定最佳工艺参数，使用差式扫描量热仪（DSC）、热重分析（TGA）、傅里叶红外光谱（FTIR）、扫描电子显微镜（SEM）和激光粒度仪测定其理化性质，并研究微胶囊在胃肠液中的释放特性及贮藏稳定性。结果表明，当海藻酸钠浓度1.5%，CaCl₂浓度2.5%，芯壁质量比1.5:1，乳化温度50 ℃，固化时间30 min时，微胶囊包埋率最高为89.41%；含水量为5.25%、溶解度为57.22%、休止角为20.6°；平均粒径为929.773 μm，酥油在微胶囊化后热稳定性提高；释放实验表明，微胶囊在模拟胃液、肠液中释放率分别为11.52%、96.44%；贮藏实验表明，微胶囊货架期较牦牛酥油显著延长。