Pork Lard Research Articles

Biopolymeric emulsions with added silicon as pork fat substitutes in the reformulation of healthy pâtés: Effect on technological, nutritional and sensory properties and on lipid digestibility after in vitro gastrointestinal digestion

Four different pork lard emulsions were elaborated in order to be used as pork backfat replacers in the reformulation of healthy pâtés: an emulsion stabilized with soy protein concentrate (SPC, E1), E1 with added silicon (Si) (E2), E1 with a mixture of methylcellulose (MC) and carboxymethylcellulose (CMC) (E3), and E3 with added Si (E4). These four emulsions were characterized in terms of texture, color and in vitro gastrointestinal digestion (GID) and were then used in the reformulation of four pork liver pâtés (PE1-PE4). These pâtés were compared to a control pâté elaborated with 100% pork backfat (PC). The technological, nutritional and sensory properties of the pâtés were assessed, along with lipid digestibility based on the content of free fatty acids (FFAs) released after in vitro GID. The reformulated pâtés had highly adequate physicochemical and sensory properties, comparable to those of the PC control. The addition of a mixture of MC/CMC and Si in the SPC-stabilized emulsion caused a slow down of in vitro GID and, consequently, lower lipid bioaccessibility (BA) of the main fatty acids when E3 and E4 were incorporated into the reformulated pâtés PE3 and PE4. Si BA was higher in the absence of cellulose ethers (14.6%) that in their presence (8.84%).

Radiation dose and image quality optimization in lumbar spine digital radiography for overweight and obese patients: Phantom study

Background: Lumbar spine radiography plays an important role in routine use for clinical practice in overweight and obese patients. The radiographer is responsible for setting suitable exposure factors for the tradeoffs between radiation dose and image quality (IQ). Objective: To investigate the effect of different kVp values combined with AEC used on radiation dose and IQ for routine lumbar spine radiography in overweight and obese patients. Materials and methods: A 1.5 and 3 cm thickness of frozen pork lard was placed on a pelvis phantom to simulate an overweight and obese patient, respectively. The phantom was imaged at 10 kVp intervals in combination with AEC used. For IQ evaluation, CNR and SNR were calculated, and the observer study was determined using visual grading scores (VGS) with a 5-point Likert scale. The radiation dose was measured using a DAP meter, and then the figure of merit (FOM) was calculated. Results: SNR and CNR for both AP and lateral projection showed a slightly decreasing trend when kVp increased in all groups. The DAP values decreased when the higher kVp was selected with AEC used in each group. The VGS by five radiographers showed good image quality in all groups, while the FOM at 100 and 109 kVp was the highest score for both AP and lateral projections. Conclusion: The optimal kVp setting in this study ranged from 100 to 109 kVp in combination with AEC used, indicating minimal radiation dose, while maintaining diagnostic IQ.

Reduction of oxidative rancidification of fungal melanin-coated films in pork lard preservation in trading.

Storage of meat has always been challenging due to its deterioration caused by oxidative rancidity and microbial activity, especially in trading. The melanin-coated film acts as a potent antioxidant, prevents the oxidation of fatty acids, and neutralizes the reactive oxygen species (ROS) helping to withstand or perpetuate the oxidative stress of meat. This study emphasizes the production of fungal melanin extracted from Curvularia lunata and the preparation of two different melanin film combinations of gelatin/melanin and agar/melanin at 0.1% and 0.5% formulation for rancidity stability of coated pork lard. Interpretations revealed the delayed rancidity in both peroxide and acid values with 5.76% in 0.5% agar-coated melanin up to the 11th day which was supported by arithmetical analysis showing p < 0.05 are statistically significant. Further, upon testing the brine shrimp assay for melanin toxicity, 7% were in a mortal state at 1000 µg/mL concentration, considered zero lethality. This result implies that modified coatings, particularly when trading meats, that include fungal melanin can effectively prevent the oxidation of pork lard.

Impact of Silicon Addition on the Development of Gelled Pork Lard Emulsions with Controlled Lipid Digestibility for Application as Fat Replacers.

Pork lard gelled emulsions stabilized with two proteins [soy protein concentrate (SPC) or a pork rind protein extract (PRP)], both with and without added silicon (Si) from diatomaceous earth powder, were gelled by microbial transglutaminase and к-carrageenan. These gelled emulsions (GEs), intended as fat replacers, were evaluated in different aspects, including microstructure and technological properties during chilling storage. In addition, in vitro gastrointestinal digestion (GID) with an analysis of lipolysis and lipid digestibility was also evaluated. All GEs showed adequate technological properties after 28 days of chilling storage, although the SPC-stabilized GEs showed better gravitational and thermal stability (~4% and ~6%, respectively) during chilling storage than the PRP-stabilized ones (~8 and ~12%, respectively). PRP developed larger flocculates restricting pancreatic lipase-mediated lipolysis during intestinal digestion. The addition of Si to both GE structures protected them against disruption during in vitro digestion. Accordingly, Si appears to slow down fat digestion, as reflected by higher triacylglycerides content after GID (15 and 22% vs. 10 and 18% in GEs without Si) and could become a potential candidate for use in the development of healthier meat products.

Short-Term Changes in Aroma-Related Volatiles in Meat Model: Effect of Fat and D. hansenii Inoculation.

This study assessed the effect of replacing pork lard with coconut oil and Debaryomyces hansenii inoculation on the biotransformation of amino acids into volatile compounds in a meat model system. Yeast counts, solid-phase microextraction, and gas chromatography/mass spectrometry were used to assess yeast growth and volatile production, respectively. Yeast growth was confirmed until 28 d, although the volatile profile changed until 39 d. Forty-three volatiles were quantified, and their odor activity values (OAVs) were calculated. The presence of fat and yeasts contributed to differences in volatiles. In pork lard models, a delayed formation of lipid-derived aldehyde compounds was observed, whereas in coconut oil models, the generation of acid compounds and their respective esters was enhanced. Yeast activity affected amino acid degradation, which produced an increase in branched-chain aldehydes and alcohols. The aroma profile in the coconut models was influenced by hexanal, acid compounds, and their respective esters, whereas in pork lard models, aroma was affected by methional (musty, potato) and 3-methylbutanal (green, cocoa). The yeast inoculation contributed to the generation of 3-methylbutanoic acid (cheesy) and phenylethyl alcohol (floral). The type of fat and yeast inoculation produced a differential effect on the aroma.

Metabolic Syndrome in Hypertriglyceridemic Rats: Effects of Antioxidants.

Long-lasting disturbances in lipid and glucose metabolism present in metabolic syndrome (MetS) lead to serious cardiovascular diseases. The study was aimed to evaluate the effect of natural antioxidant vitamin E (VitE, 100 mg/kg/day, p.o.) on basal biochemical and physiological parameters characterizing MetS and on the changed function of the heart. Furthermore, the possible potentiation of VitE effect by synthetic pyridoindole antioxidant SMe1EC2 (SMe, 15 mg/kg/day, p.o.) was also tested. MetS was induced in hereditary hypertriglyceridemic rats (HTG) by the 5 weeks administration of high-fat fructose diet (HFFD: 1 % cholesterol, 7.5 % pork lard, 10 % fructose). The heart function was tested using Langendorff preparation under constant pressure. The functional parameters of isolated heart, dysrhythmias and evoked fibrillations were evaluated in conditions of ischemia-reperfusion. The HFFD increased body weight gain and serum levels of total cholesterol, low-density lipoproteins and blood glucose. The HFFD significantly increased heart flow and force of contraction, compared to standard diet (SD). During the reperfusion, the HFFD caused the increase of the ventricular premature beats number at the expense of decreasing the duration of serious dysrhythmias (ventricular tachycardias and fibrillations). The addition of VitE, SMe or their combination to the HFFD decreased body weight gain, depressed blood pressure, improved particular biochemical parameters. The combination of VitE and SMe suppressed the occurrence of serious dysrhythmias. Our data indicate that the HFFD-related disturbances led to alterations within pathophysiology in HTG rats. The results showed that a combination of antioxidants might have the potential to amend disorders accompanying MetS.

Stabilized soy protein emulsion enriched with silicon and containing or not methylcellulose as novel technological alternatives to reduce animal fat digestion

During the last decade, the consumption of animal saturated fat has been associated with an increased risk of chronic disease. Experience shows that changing the dietary habits of the population is a complicated and slow process, so technological strategies offer new possibilities for the development of functional foods. The present work is focused on studying the impact of using a food-grade non-ionic hydrocolloid (methylcellulose; MC) and/or the inclusion of silicon (Si) as a bioactive compound in pork lard emulsions stabilized with soy protein concentrate (SPC), on the structure, rheology, lipid digestibility and Si bioaccesibility during in vitro gastrointestinal digestion (GID). Four emulsions (SPC, SPC/Si, SPC/MC and SPC/MC/Si) were prepared with a final biopolymer (SPC and/or MC) concentration of 4% and 0.24% Si. The results showed a lower degree of lipid digestion in SPC/MC compared with SPC, specifically at the end of the intestinal phase. Moreover, Si partially reduced fat digestion only when incorporated into the SPC-stabilized emulsion, while this effect was lost in SPC/MC/Si. This was probably due to its retention inside the matrix emulsion, which resulted in lower bioaccesibility than in SPC/Si. Additionally, the correlation between the flow behavior index (n) and the lipid absorbable fraction was significant, suggesting that n can be a predictive marker of the extent of lipolysis. Concretely, our results revealed that SPC/Si and SPC/MC can be used as pork fat digestion reducers and thus, they can replace pork lard in the reformulation of animal products with potential health benefits.

Reduced Digestibility of Beef Tallow and Cocoa Butter Affects Bile Acid Excretion and Reduces Hepatic Esterified Cholesterol in Rats

We investigated stearic acid (18:0) digestibility and how it affects bile acid excretion in male Sprague-Dawley rats fed diets containing (g 18:0/100 g fatty acids): pork lard (13); beef tallow (19); cocoa butter (35); corn oil (2) or corn oil plus cholestyramine for 25 d. Apparent lipid digestibility was reduced with increased dietary intake of 18:0 as follows: lard (90%), beef tallow (82%), cocoa butter (78%), cholestyramine (87%), and corn oil (94%); P < 0.001, pooled SD = 2. Hepatic concentrations of total and esterified cholesterol were significantly less in cocoa butter-, beef tallow- and cholestyramine-fed groups compared with lard- and corn oil-fed groups. Fecal bile acid excretion was significantly greater in rats fed cocoa butter or cholestyramine compared with those fed corn oil. The half-life of intraperitoneally administered 14C-cholic acid was significantly longer in rats fed cocoa butter (1.36 ± 0.02 d) compared with cholestyramine (0.98 ± 0.03 d) and intermediate in those fed corn oil, lard or beef tallow (1.11–1.21 ± 0.05 d). Fecal excretion of muricholic acids (bile acids) correlated strongly with dietary intake of 18:0 (r2 = 0.98, P < 0.01), whereas excretion of bile acids derived from cholic and chenodeoxycholic acids was similar among groups. In summary, the lower digestibility of cocoa butter is associated with increased fecal bile acid excretion, reduced hepatic concentration of esterified cholesterol, decreased fractional turnover of 14C-cholic acid and increased excretion of muricholic acids in rats. The mechanism by which stearate-rich dietary fats alter bile acid and cholesterol metabolism is, however, uncertain.

Effects of Omega-3-Rich Pork Lard on Serum Lipid Profile and Gut Microbiome in C57BL/6NJ Mice.

Hyperlipidemia is a risk factor for cardiovascular diseases. This study is aimed at investigating the effects of consuming omega-3-rich pork lard on the serum lipid profile and gut microbiome of the mice model. We divided 23 C57BL/6NJ males (16-week-old) into 3 groups, and each group received either a control diet, a high-fat diet of coconut oil (coconut oil), or a high-fat diet of omega-3-rich pork lard (omega lard) for 28 days. Thereafter, fasting serum lipids and fecal microbiomes were analyzed. The serum cholesterol, triglyceride, and LDL levels of the omega lard-treated group were significantly reduced compared to the coconut oil-treated group (P < 0.05). However, the microbiome analysis revealed a significant increase in the abundance of Lachnospiraceae in the omega lard-treated group compared to the coconut oil-treated group (P < 0.05). Furthermore, Spearman's correlation analysis revealed that the increased serum lipid content was positively correlated with the abundance of Bacteroidaceae (P < 0.05) and negatively correlated with the abundance of Lachnospiraceae (P < 0.05). These findings suggested that omega-3-rich pork lard altered the serum lipid profile and gut microbiome in the mice model. Practical Application. The excellent protection offered by omega-3-rich pork lard against hyperlipidemia indicated that pork lard could be used as alternative cooking oil for health-conscious individuals. It could also be introduced as a functional ingredient for patients with hyperlipidemia.

Pork Lard Derived Biodiesel Production: Characterization, Engine Performance and Emission Analysis

The present work introduces a new methodology in the production of biodiesel from pork-lard waste having high cholesterol content and discusses its improved performance and emissions in a diesel engine. The traditional method of transesterification does not work with cholesterol due to the absence of triglycerides, therefore, the new improved method oxidizes cholesterol to fatty acids and then converts it to biodiesel ester. The procedure includes an acid reagent to break cholesterol and a renewable basic catalyst from seashells, for catalyzing the production. The acid-base system maintains the overall pH while yielding 95.6% conversion at the optimized conditions. The morphology of the produced catalyst was analyzed through FESEM and confirmed through XRD and EDX analyses. The physicochemical and ASTM properties were determined and the calorific value of the 20% biodiesel blend was found to be comparable with that of diesel. From the engine performance analysis, the thermal efficiency of the engine was observed to be higher and the exhaust emissions showed a maximum of 75% reduction in CO and 42.2% reduction in CO2 emissions, proving it to be an environment-friendly fuel. Additionally, a 32.7% reduction in smoke opacity was also observed, thus decreasing the concentration of particulate matter in the atmosphere.

Development of rapid low temperature assistant modified QuEChERS method for simultaneous determination of 107 pesticides and relevant metabolites in animal lipid

A modified QuEChERS LC-MS/MS method was developed for 107 pesticides analysis in animal lipids such as pork lard, mutton tallow, chicken oil and butter. The challenges for high fat matrices clean up were studied in details by optimizing dispersive purification adsorbents coupled with rapid low temperature assistant methods. The method validation was carried out using pork lard and further appplied to other matrices by testing their recoveries. Good linearities were obtained with correlation coefficients greater than 0.99. Sensitive LOQs ranged from 5.0–50.0 μg kg−1. Both inter-day and intra-day precisions were lower than 20% indicating the good precision and accuracy of this method. The method applied to four animal lipids with 93%∼100% of analytes revealed satisfactory recoveries (ranged from 70% to 120%) and RSD (≤20%) at 10 µg kg−1and 50 µg kg−1 spiking levels respectively related to the matrix.

THE YIELDS AND PROFITABILITY OF CATFISH JUVENILES FED DIETS FROM NON-CONVENTIONAL FEEDSTUFFS.

Three diets were formulated and produced with Dried Broiler manure (DBM), Maize Offal (MO), Cassava flour meal (CF), Thrashed tilapia Fish (TTF)b and pork-lard (PL). They were compared with conventional feed ingredients for growth, survival, nutrients utilization and cost evaluation indices in 150 days. The biological data obtained from the fish fed at 5% biomass did not revealed any significant differences (P&gt;0.05) between the test diets and the reference. The cost evaluation of feeds and fish revealed significant differences (P&lt;0.05) in feed cost and profit index with higher values in non-conventional diets

The Effects of Increasing Dietary Fat on Serum Lipid Profile and Modification of Gut Microbiome in C57BL/6N Mice

Hyperlipidemia is a condition where the blood shows an elevated level of lipid, such as cholesterol and triglyceride. It is considered a risk factor for all coronary artery death globally. Association of microbiome with non-communicable diseases (NCDs) including hyperlipidemia has been reportedly associated. In this study, we hypothesize that the change in microbiome is correlated to the change in serum lipid level, which resulted by increasing dietary fat consumption. The 32 male, 14-week-old, C57BL/6N were divided into 4 groups, each group received control diet, 10%, 20%, and 40% kcal fat diet prepared from purified pork lard, respectively for 28 days. Fasting serum lipids and fecal microbiome were then analyzed. The group of animals assigned to 40% kcal fat showed significantly increased serum cholesterol, LDL, and HDL (p < 0.05). Microbiome analysis revealed the abundance of Muribaculaceae and Saccharimonadaceae were significantly decreased (p < 0.05). On the contrary, the abundance of Clostridia_UCG014, Akkermansiaceae, Bacteroidaceae, Oscillospiraceae, and Erysipelotrichaceae were significantly increased (p < 0.05). Spearman correlation indicated that the abundance of Akkermansiaceae and Bacteroidaceae were positively associated with the increased of serum cholesterol and LDL (p < 0.05), while the abundance of Muribaculaceae, Clostridia_UCG-014, and Saccharimonadaceae were negatively associated (p < 0.05). These results suggest that dietary fat have ability to manipulated microbiome with relative to elevation of serum lipid profile.

5-Dodecanolide, a Compound Isolated from Pig Lard, Presents Powerful Anti-Inflammatory Properties.

Background: Pork lard (PL) is traditionally used as an anti-inflammatory agent. We propose to demonstrate the anti-inflammatory properties of PL, and elucidate which compounds could be responsible for the anti-inflammatory effects. Methods: The anti-inflammatory effects of PL were tested in a rat model of zymosan-induced hind paw inflammation. Further, the hydroalcoholic extract from PL was obtained, the composition analyzed, and the anti-inflammatory activity of the extracts and isolated components assayed using immune cells stimulated with lipopolysaccharide (LPS). Results: Applying the ointment on the inflamed rat feet reduced the foot diameter, foot weight, and activities of antioxidant enzymes and inflammatory markers of circulating neutrophils. The main components of the hydroalcoholic extract were 5-dodecanolide, oleamide, hexadecanoic acid, 9-octadecenoic acid, hexadecanamide, and resolvin D1. Conclusions: PL reduces the immune response in an animal model stimulated with zymosan. Hydroalcoholic PL extract and its components (5-Dodecanolide, Oleamide, and Resolvin D1) exerted an anti-inflammatory effect on LPS-stimulated neutrophils and peripheral mononuclear cells reducing the capability to produce TNFα, as well as the activities of antioxidant and pro-inflammatory enzymes. These effects are attributable to 5-dodecanolide, although the effects of this compound alone do not reach the magnitude of the anti-inflammatory effects observed by the complete hydroalcoholic extract.

Connecting science, policy, and practice in agri-food system transformation: The role of boundary infrastructures in the evolution of Brazilian pig production

Scholars have often applied the concept of boundary work and its conceptual progeny to explain how science, policy, and practice collaborate to introduce change into agrifood systems. However, previous studies focused primarily on specific boundary elements (i.e., boundary spanners, boundary organizations, and boundary objects) or particular innovation processes (in terms of scope or timescale) within broad transformative change. This study aims to deepen the understanding of long-term transformative processes in agri-food systems by looking at how boundary infrastructures influenced the evolution of the Brazilian pig production system from a setting in which it mainly produced pork lard for a domestic market to a setting of being integrated in global supply chains and following international standards. Mainly, we add to the extant literature by highlighting that boundary infrastructures influenced the longterm transformative process experienced by BPPS by establishing a space where science-policy-practice interactions legitimized particular visions and values and instilled responsibility and accountability to spur various joint actions in support of innovation. We also contribute to the extant literature by showing that boundary infrastructures evolution in BPPS was incremental, long-term, multi-site, and with intertwined leverage. Boundary infrastructures provide structuration to system transformation and are also (re)structured while transitions unfold. Since boundary infrastructures have a certain directionality and may become hegemonic and exclusionary, this requires sensitiveness to the need to reorient a hegemonic boundary infrastructure or create a parallel one. Our study deepens the understanding of how coordination unfolds in long-term transformative processes, a topic deemed of interest given current debates on promoting agri-food systems transformation. We argue that better awareness of boundary infrastructures in which science-policy-practice interactions occur can help guide the direction of innovation to support sustainability transitions in agri-food systems.

Effect of Dietary Lipid Sources on Feed Utilization, Growth Efficiency and Carcass Composition of Clarias gariepinus Juveniles

This study was designed to investigate plant and animal lipid that can enhance feed utilization, growth, and survival of Clarias gariepinus Juveniles. Juveniles with mean weight 32.50±0.5g were stocked randomly to seven tanks replicated thrice, with each tank having seven fish each and were fed with the prepared diets with varied lipid. 40% crude protein and isocaloric diets with digestible energy of 2,933.76Kcal were formulated and labelled Diet 1-7 with different sources of plant and animal lipids. Diet 1, 2 and 3 contained palm oil, Groundnut oil and soybean oil respectively, while diet 4, 5 and 6 contained Pork lard, Cod Liver oil and Beef tallow. Diet 7 (Control diet without any lipid source).&#x0D; The result showed that there was no significant difference (P&gt;0.05) in Feed conversion ratio (FCR) and survival rates among the diets. The mean weight gain was highest in fish fed with pork lard (22.12g) while the lowest value of 15.36g was recorded in fish fed with soybean oil. Relative weight gains and feed intake showed no significant difference (P&gt;0.05) between fish fed lipids of plant origin. However, there was significant difference (P&lt;0.05) among fish fed lipids from animal origin. The Highest Total Cholesterol (28.18 mg/dl) was recorded in fish fed beef tallow as lipid sources while the least value of low-density cholesterol (value of 2.26 mg/dl) was recorded in fish fed with soybean oil. In conclusion, C. gariepinus was able to utilize animal-based lipid sources more in terms of growth and feed utilization while the lipid profile result of the individual carcass after the culture period showed that C. gariepinus fed lipid from plant sources had a slightly better cholesterol level than those fed lipid of animal sources.

Efficacy of Norway Spruce Ointments and Bacterial and Fungal Alterations in the Treatment of Castration Wounds in Piglets.

This study aimed to evaluate the efficacy of Norway spruce ointments on wound healing of castration wounds in piglets. This study included 95 male pigs randomly divided into five treatment groups: Norway spruce balm (Vulpuran), Norway spruce resin (Abilar), pork lard (ointment base of Vulpuran), no treatment (negative control) and antibiotic blue spray (Cyclo spray, positive control). Wound healing parameters (such as healing time, wound size, reddening of wound edges and surrounding, swelling, secretion and wound contamination), microbiological status and the haptoglobin level as an inflammation parameter were investigated. In the Norway spruce groups, some positive effects on wound healing parameters were found. In the first 6 days of treatment, Abilar or Vulpuran showed the smallest means of wound areas, and at the end of the study (day 15 + 17), the highest rates of completely closed wounds compared to the other groups. Vulpuran treatment led to significantly lower wound secretion (p = 0.003) and wound contamination (p = 0.015) than the untreated control did. Furthermore, the microbiological status was determined using MALDI-TOF-MS and partial 16S rRNA gene sequencing at different days of treatment. A comparison of the five treatment groups on day 3 revealed that Norway spruce led to the lowest rate of wounds colonised with fungi, mainly classified into genus Candida, (Abilar 77%, Vulpuran 70%) in comparison with blue spray (89%), lard (100%) and untreated control (100%). Fungi could only be detected in one of the 13 samples treated with Vulpuran on day 8, which nearly reached significance (p = 0.055).

Effect of lipid sources on growth performance, muscle composition, haemolymph biochemical indices and digestive enzyme activities of red swamp crayfish ( Procambarus clarkii )

This study was conducted to determine the effects of different dietary lipid sources on red swamp crayfish (Procambarus clarkii). Six diets were formulated with the same lipid level (85 g/kg) to contain fish oil (FO), soybean oil (SO), corn oil (CO), palm oil (PO), lecithin oil (LO) and pork lard (PL) respectively. Each diet was fed to triplicate of 18 crayfish with an initial weight of (13.05 ± 0.60) g for 8 weeks. The results showed that crayfish fed diet SO had a significantly higher weight gain rate and specific growth rate than those fed diet CO, PO and PL, but there was no significant difference among crayfish fed diet FO, SO and LO. Crayfish fed diet PL had the highest feed conversion ratio and the lowest survival rate. Significantly increased muscle lipid contents were observed in groups PO and PL compared with other groups. Group FO had the highest values of EPA, DHA and n-3/n-6 ratio in muscle, followed by groups LO and SO. The haemolymph triacylglycerol content was the highest, whereas alkaline phosphatase activity was the lowest in crayfish fed diet PL. Moreover, a significant increase of total protein content was observed in the haemolymph of crayfish fed diet FO, SO and LO. In conclusion, crayfish fed diet FO, SO and LO showed better growth than those fed diet PL and PO without any signs of essential fatty acid deficiency.

Effect of baking powder as a substitute of pork lard on the texture of Mexican tamales

In order to encourage the efforts of nutritionists and public policies to reduce the caloric value of traditional food, and to increase the knowledge about Mexican and Latin American traditional cuisines, the aim of this study was to evaluate the effect of fat reduction and its replacement with a leavening agent on the texture properties of Mexican tamales. Through a full factorial 22 experimental design, the combined effect of pork lard and baking powder on tamales texture properties was evaluated. The levels of each factor were 0.0 and 27.3 g of pork lard and 0.0 and 0.68 g of baking powder per 100 g of tamales dough including a central experimental unit (13.65 g of pork lard and 0.34 g baking powder per 100 g of tamales dough). The decrease in pork lard causes a significant increase in tamales chewiness. However, baking powder prevents the chewiness increase caused by the decrease in tamales fat content slightly affecting their adhesiveness. At the highest level of pork lard, baking powder does not cause significant changes in tamales texture but in the absence of fat, the leavening agent causes a desirable texture, similar to the traditional texture of these food products. Fat globules, identified by light microscopy, surround the starch granules and may be the cause of the increase in tamales adhesiveness.

Chitosan preparations with improved fat‐binding capacity

AbstractChitosan is a polycationic polysaccharide with good health and nutritional benefits. This study investigated the effect of chitosan properties, such as, biopolymer structure, viscometric molar mass (Mv), and degree of deacetylation (DD), on the fat‐binding capacity between five chitosan preparations (different origins and characteristics) and three types of fat (soybean oil, margarine, and pork lard). The in vitro fat‐binding tests were performed with soybean oil under different pH to simulate the digestion process in the gastrointestinal tract, followed by tests at constant pH (duodenal pH = 6.8) with three types of fat. Shrimp shell nanochitosan had an average hydrodynamic diameter of 62 nm, while that of shrimp shell chitosan and commercial chitosans (CC1, CC2, and CC3) ranged between 1090 and 1405 nm (determined by DLS). The Mv of chitosan varied between 18 and 260 kDa, and the DD ranged from 62% to 92%. Chitosan with medium Mv and high DD presented better results of fat‐binding capacity in the duodenal pH with soybean oil. This study provides insights into the mechanisms of fat‐binding capacity and its correlation with physicochemical properties of chitosan, pH, and type of fat, allowing the production of chitosan‐based products with improved fat‐binding capacity for several applications.