Microencapsulation of Lactobacillus rhamnosus GG by Transglutaminase Cross‐Linked Soy Protein Isolate to Improve Survival in Simulated Gastrointestinal Conditions and Yoghurt

Microencapsulation is an effective way to improve the survival of probiotics in simulated gastrointestinal (GI) conditions and yoghurt. In this study, microencapsulation of Lactobacillus rhamnosus GG (LGG) was prepared by first cross‐linking of soy protein isolate (SPI) using transglutaminase (TGase), followed by embedding the bacteria in cross‐linked SPI, and then freeze‐drying. The survival of microencapsulated LGG was evaluated in simulated GI conditions and yoghurt. The results showed that a high microencapsulation yield of 67.4% was obtained. The diameter of the microencapsulated LGG was in the range of 52.83 to 275.16 μm. Water activity did not differ between free and microencapsulated LGG after freeze‐drying. The survival of microencapsulated LGG under simulated gastric juice (pH 2.5 and 3.6), intestinal juice (0.3% and 2% bile salt) and storage at 4 °C were significantly higher than that of free cells. The survival of LGG in TGase cross‐linked SPI microcapsules was also improved to 14.5 ± 0.5% during storage in yoghurt. The microencapsulation of probiotics by TGase‐treated SPI can be a suitable alternative to polysaccharide gelation technologies.     

Indian Meal Moth (Plodia Interpunctella)–Resistant Food Packaging Film Development Using Microencapsulated Cinnamon Oil

Insect‐resistant laminate films containing microencapsulated cinnamon oil (CO) were developed to protect food products from the Indian meal moth (Plodia interpunctella). CO microencapsulated with polyvinyl alcohol was incorporated with a printing ink and the ink mixture was applied to a low‐density polyethylene (LDPE) film as an ink coating. The coated LDPE surface was laminated with a polypropylene film. The laminate film impeded the invasion of moth larvae and repelled the larvae. The periods of time during which cinnamaldehyde level in the film remained above a minimum repelling concentration, predicted from the concentration profile, were 21, 21, and 10 d for cookies, chocolate, and caramel, respectively. Coating with microencapsulated ink did not alter the tensile or barrier properties of the laminate film. Microencapsulation effectively prevented volatilization of CO. The laminate film can be produced by modern film manufacturing lines and applied to protect food from Indian meal moth damage.     

Chromium in the gastrointestinal tract of the rat

Chromium from feed intrinsically labelled with ⁵¹Cr was either fed to laboratory rats or mixed in vitro with gastrointestinal tract contents. The solubility, protein association and molecular size were measured. Chromium from intrinsically labelled feed did not appear as inorganic chromium in the gastrointestinal tract of the rat. One-fourth to one-half of the chromium in the small intestine remained in solution after centrifugation for 10 min at 12000 × g. The chromium in solution had the same exclusion volume on gel filtration chromatography throughout the gastrointestinal tract. Any protein association was quite labile. With high-fibre feed, more chromium was not soluble and probably was not available for absorption. Chromate administered with feed formed complexes with the feed and behaved similarly to intrinsically labelled feed. Chromate fed to fasted rats associated with large, possibly protein-containing, sedimentable particles in the gastrointestinal tract of the rat.     

Effect of Microencapsulation of Dietary Oil on Postprandial Lipemia

ABSTRACT: Microencapsulation is increasingly applied to dietary oils, but only limited information is available about the effect on bioavailability. The aim of the present study was to evaluate the bioavailability of microencapsulated vegetable oil from a liquid food product in a clinical trial. Another aim was to compare the suitability of sodium octenyl succinate starch (SOSS) and oat starch aggregate (OSA) in sustained release of a vegetable oil. Twenty-four healthy young men were recruited and randomly allocated into 1 of 3 groups (A, B, C). All subjects consumed 2 liquid test meals, which differed only with respect to microencapsulation. Groups A and B consumed berry juice or fermented oat drink, respectively, containing either non-encapsulated or SOSS-encapsulated blackcurrant seed oil (BCO). Group C received sea buckthorn oil (SBO) encapsulated with SOSS or OSA. Blood samples were collected at 0,30,60,90,180,270, and 360 min after the meal, and chylomicron-rich (CM-rich) fraction was separated for subsequent triacylglycerol (TAG) analysis. Microencapsulation increased the glycemic response. SOSS-encapsulated BCO resulted in a similar CM-rich TAG response as non-encapsulated BCO, indicating that the SOSS-encapsulated oil was fully bioavailable. OSA-encapsulation had a similar bioavailability. The lipemic response of subjects who consumed the oil mixed in the fermented oat drink was higher than that of other subjects. This most likely resulted from the slightly higher fat and energy content of the fermented oat drink compared with berry juice. Contrary to expectations, the use of OSA in microencapsulation did not result in sustained release.     

Microencapsulation of Lactobacillus reuteri DSM 17938 Cells Coated in Alginate Beads with Chitosan by Spray Drying to Use as a Probiotic Cell in a Chocolate Soufflé

The main objective of this work was to obtain microencapsulated probiotic cells in order to improve their resistance to heat stress and gastrointestinal conditions. A further aim was to obtain a potentially probiotic chocolate soufflé. Lactobacillus reuteri DSM 17938 cells were microencapsulated by spray drying in alginate matrix and further coated with chitosan. Bacterial survival after exposure to different heat treatments and simulated gastrointestinal conditions were measured to test the microcapsules. They were also dyed by using a LIVE/DEAD^® BacLight? Bacterial Viability Kit and characterized by epifluorescence microscope observation. Furthermore, a potentially chocolate soufflé was prepared using microencapsulated cells. The results indicated that alginate microcapsules did not improve acid tolerance or heat resistance in “in vitro” experiments, while they were able to protect 7% of the Lactobacillus reuteri population during the baking of a chocolate soufflé, compared to a survival rate of 1% of free cells. By contrast, the cells microencapsulated with alginate coated with chitosan showed, compared to free cells, improved acid tolerance, allowing the cell population to remain constant after 3 h in simulated gastric conditions. Moreover, the heat resistance of cells in co-cross-linked microcapsules significantly improved compared to free cells, both in “in vitro” and “in food” experiments. Microencapsulation led to a survival rate of 10% after baking a chocolate soufflé. However, the final level of bacterial cells in the product was too low to consider the chocolate soufflé as a probiotic product.     

Encapsulation of lipid by alginate beads reduces bio-accessibility: An in vivoC breath test and MRI study

This paper describes an in vivo study of the use of encapsulation to alter lipid bio-accessibility in the gastro-intestinal (GI) tract. The hypothesis that encapsulation would delay the accessibility of lipid in the GI tract was tested using subjects (N = 11) who consumed either 30 g of ¹³C-labelled sunflower oil encapsulated within 70 g alginate gel particles, or unencapsulated ‘free’ sunflower oil and alginate-only particles (control). Lipid accessibility was determined by the appearance of the ¹³C label in breath carbon-dioxide (CO₂), and the particles behaviour in the GI tract was investigated using non-invasive magnetic resonance imaging (MRI).     

In vitro and in vivo antithrombotic and antioxidant properties of microencapsulated brewers’ spent grain peptides

Antioxidant and antithrombotic activities of microencapsulated brewers’ spent grain peptides (BSGH-C) after simulated gastrointestinal digestion (SGID) and the in vivo properties using a model of growing Wistar rats fed with sucrose-rich diet (SRD) were determined. Microencapsulation reduced the cleavage of peptides (66.5 vs. 39.2%), partially preserved the in vitro antioxidant activity (ABTS⁺ inhibition and FRAP) and reduced the in vitro antithrombotic activity. SRD diet produced a pro-oxidant and pro-thrombotic systemic environment in rats, which was reversed by the consumption of BSGH-C. A positive correlation between in vitro antioxidant and antithrombotic activity of BSGH-C after SGID with the respective in vivo effects observed in rats fed BSGH-C (r = 0.9997 and r = 0.9411, respectively) was established. The goodness of both, the in vitro models determining bioactive properties after SGID, and the microencapsulation protecting the peptides from gastrointestinal environment were demonstrated. Thus, it was possible to produce microcapsules with bioavailable bioactive BSG peptides.     

Disintegration of solid foods in human stomach

ABSTRACT:  Knowledge of the disintegration of solid foods in human stomach is essential to assess the bioavailability of nutrients in the gastrointestinal (GI) tract. A comprehensive review of food gastric digestion, focusing on disintegration of solid foods, is presented. Most of the research reviewed in this paper is contained in the medical, pharmaceutical, food, and nutritional literature. Stomach physiology is briefly introduced, including composition and rheological properties of gastric contents, stomach wall motility in fed/fasted states, and hydrodynamic and mechanical forces that act on the ingested food. In vivo and in vitro methods used for studying food and drug digestion in GI are summarized. Stomach emptying rate, which controls the rate of absorption of nutrients, is highly related to the disintegration of foods. This topic is highlighted with focus on the important mechanisms and the influence of chemical and physical properties of foods. Future research in this area is identified to increase our fundamental understanding of the food digestion process in the stomach as related to the food composition, material properties such as texture and microstructure, and chemical characteristics. This information is necessary to develop new guidelines for seeking innovative processing methods to manufacture foods specifically targeted for health.     

Study of the incorporation of native and microencapsulated chia seed oil on pasta properties

The present work studied the effect of the incorporation of encapsulated chia seed oil on the cooking quality of dry pasta. Pasta morphology and oil distribution in the samples were studied. No significant variations were determined in cooking parameters as optimal cooking time, cooking loss and texture of cooked pasta with the incorporation of the encapsulated oil, but significant differences were determined in uncooked pasta texture and variables that describe water interaction, such as water absorption and swelling index. In addition, the incorporation of microencapsulated oil avoided oxidative deterioration, showing a protective effect and preventing the formation of hydroperoxide radicals in pasta preparation, storage and cooking procedures (compared with free oil-containing pasta), resulting in a safer product. Storage at modified atmosphere exerts an additional protective effect on oil, enhancing the effect of the microcapsules. Microencapsulation proved to be an effective technology that preserves oil quality in ω-3 rich pasta.     

Characteristic of microencapsulated 1,3-dioleoyl-2-palmitoylglycerol and its application in infant formula powder

1,3-Dioleoyl-2-palmitoylglycerol (OPO) is used widely as a food additive. However, the structured lipid is sensitive to oxygen and light in the production process. This results in the loss of its original nutrition and production of harmful substances. In this study, the OPO was microencapsulated using whey protein isolate and maltodextrin as the wall material and monostearin as an emulsifier by spray-drying technology added to the infant formula milk, in order to improve its oxidative stability. The OPO microcapsules were released in vitro through the simulated gastrointestinal tract; sensory evaluation of microencapsulated OPO in infant formula powder and nutrition absorption of microencapsulated OPO in infant formula power by animal experiments were investigated. The results showed that OPO microcapsules have a slow-release effect; after 2 h of simulated gastric fluid digestion, only 16.1 ± 3.2% of the oil was released from microencapsulated OPO, and after another 2 h of simulated intestinal fluid digestion, there was 92.3 ± 2.8% of oil released from the microencapsulated OPO. The infant formula with microencapsulated OPO has a uniform colour and no odour. The quality of infant formula with microencapsulated OPO was obviously better than infant formula with OPO by storage test. Everted mice gut sac experiments confirmed that microencapsulation did not affect absorption of mice to OPO in infant formula and prevented the loss of calcium. The study confirmed that addition of microencapsulated OPO makes infant formula more efficient for product quality and nutrition absorption.     

Enrichment of Chicken Nuggets with Microencapsulated Omega-3 Fish Oil: Effect of Frozen Storage Time on Oxidative Stability and Sensory Quality

This work studies for the first time the elaboration of frozen chicken nuggets enriched with microcapsules of omega-3 fatty acids using fish oil. Three types of chicken nuggets were prepared: control (C), enriched in bulk fish oil (BFO), and with added microencapsulated fish oil (MFO). Effect of length of frozen storage after pre-frying and before domestic frying was studied. The pre-fried nuggets were stored during 24 h at refrigeration temperature (0–2 °C) (T0) or during 1 month (T1M) or 3 months (T3M) in a domestic freezer at ?18 °C before frying. Length of frozen storage after pre-frying and before domestic frying promoted lipid and protein oxidative reactions in omega-3-enriched nuggets. Microencapsulation showed a protective effect against lipid and protein oxidation, especially during the first month of storage. In MFO, sensory traits were not affected by enrichment. In BFO-T0, a higher juiciness and saltiness and a less intense meat flavor in comparison with C-T0 and MFO-T0 was found. Time of frozen storage did not influence the sensory quality of chicken nuggets enriched with omega-3. Microencapsulation seems to be a promising method for enrichment of pre-fried frozen meat products with fish oil, improving the oxidative shelf life and preserving the sensory quality characteristics of the enriched products.     

Effect of the insoluble dietary fibre from oil palm fat-free flour on digestibility in rats

This work shows the results of comparing the effects of the insoluble dietary fibre from oil palm fat-free flour and cellulose on the growth, weight, humidity and composition of faeces in adult rats (Sprague–Dawley). Five groups of rats were fed for 4 weeks. The control group was fed with a diet free of fibre, and the remaining four groups with diets containing 50 or 100 g of either oil palm fat-free flour or cellulose, respectively. The adaptation period was 4 days. The evolution of growth and food intake did not vary significantly p<0.05 regardless of the type of diet. On the other hand, faeces excretion increased by 3.3–4.7 g/day in the groups of rats fed with oil palm fat-free flour, while it increased by only 3.1–4 g/day in diets based on cellulose. A higher content of water was observed in the faeces of rats fed with insoluble dietetic fibre from oil palm fat-free flour. The apparent digestibility of the insoluble dietary fibre of oil palm fat-free flour was low (35%), showing resistance to fermentation. The digestibility of the protein tended to decrease more with the insoluble dietary fibre of oil palm than with the cellulose, which may be related. ©     

PRODUCTION OF A HIGH-GLUTAMINE OLIGOPEPTIDE FRACTION FROM GLUTEN BY ENZYMATIC TREATMENT AND EVALUATION OF ITS NUTRITIONAL EFFECT ON THE SMALL INTESTINE OF RATS

ABSTRACT In order to utilize peptide-bound rather than free glutamine for enteral nutrition, a method was developed for producing a high-glutamine oligopeptide mixture from gluten by treatment with protease. Commercially available gluten was hydrolyzed first with molsin and then with actinase to produce a hydrolysate. Sephadex G-15 adsorption chromatography applied to the hydrolysate afforded a nearly 50% glutamine containing oligopeptide fraction with a yield of 33% on a nitrogen basis. We evaluated this oligopeptide fraction by feeding trials with fasted and methotrexate-administrated rats. The oligopeptide fraction, when compared to a simulated free amino acid mixture, was significantly more effective in enhancing the mucosal protein content in fasted rats. Also, methotrexate-administrated rats fed the oligopeptide fraction were more resistant to methotrexate-induced enterocolitis than those fed a simulated free amino acid mixture.     

Acid, bile, and heat tolerance of free and microencapsulated probiotic bacteria

ABSTRACT:  Eight strains of probiotic bacteria, including Lactobacillus rhamnosus , Bifidobacterium longum, L. salivarius, L. plantarum , L. acidophilus , L. paracasei , B. lactis type Bl-O4, and B. lactis type Bi-07, were studied for their acid, bile, and heat tolerance. Microencapsulation in alginate matrix was used to enhance survival of the bacteria in acid and bile as well as a brief exposure to heat. Free probiotic organisms were used as a control. The acid tolerance of probiotic organisms was tested using HCl in MRS broth over a 2-h incubation period. Bile tolerance was tested using 2 types of bile salts, oxgall and taurocholic acid, over an 8-h incubation period. Heat tolerance was tested by exposing the probiotic organisms to 65 °C for up to 1 h. Results indicated microencapsulated probiotic bacteria survived better ( P < 0.05) than free probiotic bacteria in MRS containing HCl. When free probiotic bacteria were exposed to oxgall, viability was reduced by 6.51-log CFU/mL, whereas only 3.36-log CFU/mL was lost in microencapsulated strains. At 30 min of heat treatment, microencapsulated probiotic bacteria survived with an average loss of only 4.17-log CFU/mL, compared to 6.74-log CFU/mL loss with free probiotic bacteria. However, after 1 h of heating both free and microencapsulated probiotic strains showed similar losses in viability. Overall microencapsulation improved the survival of probiotic bacteria when exposed to acidic conditions, bile salts, and mild heat treatment.     

海豹油对高脂血症大鼠和正常大鼠血脂的影响

分别建立高胆固醇血症和高甘油三酯血症大鼠模型,经口给予海豹油,研究海豹油对两种模型大鼠血脂的干预作用,同时研究海豹油对正常大鼠血脂的影响。结果表明:对于高胆固醇血症大鼠,海豹油降低了大鼠血清TG、TC和LDL-C含量,高剂量组(0.67 g/kg)大鼠血清HDL-C含量显著升高(p <0.05),各剂量组大鼠血清HDL-C与TC比值均极显著升高(p <0.01);对于高甘油三酯血症大鼠,海豹油降低了大鼠血清TG和TC含量,并使血清HDL-C与TC比值极显著升高(p <0.01);对于正常饲养的大鼠,海豹油对大鼠的体重、食物利用率、脏器系数以及血清生化指标均无显著影响。综上,经口给予高胆固醇血症或高甘油三酯血症大鼠海豹油,可有效降低两种模型大鼠血清TC和TG含量,而经口给予正常饲养大鼠海豹油,不会对正常大鼠的体重、摄食、血清生化指标以及各种脏器造成影响。     

Freeze drying technique for microencapsulation of Garcinia fruit extract and its effect on bread quality

Microencapsulation is an enduring technology for protection and controlled release of food ingredients. The Garcinia cowa fruit rinds are rich source of (−)-hydroxycitric acid (HCA), which is reported to have various health benefits. But, HCA is hygroscopic in nature and thermally sensitive. Hence, G. cowa fruit extract was microencapsulated using three different wall materials such as whey protein isolate (WPI), maltodextrin (MD) and combination of whey protein isolate and maltodextrin (WPI + MD in 1:1 ratio) by freeze drying at 30% concentration. The microencapsulated powders were evaluated for their impact on bread quality and free HCA concentration. The microcapsules exhibited wider particle size range of 15–100 μm and HPLC analysis showed that all the three encapsulates yielded higher free (above 85%) and net (above 90%) HCA recovery. Moreover, bread with WPI encapsulates exhibited higher volume, softer crumb texture, desirable colour and sensory attributes and had higher free HCA concentration. This indicated that WPI has excellent encapsulation efficiency than other two wall materials during bread baking.     

Textural,Color, Hygroscopic,Lipid Oxidation,and Sensory Properties of Cookies Containing Free and Microencapsulated Chia Oil

Encapsulation of chia oil might protect omega-3 and omega-6 from lipid oxidation when producing baked foods. However, the actual gain in stability given by chia oil must be determined. In this work, chia oil or chia oil-loaded microparticles were added to a cookie formulation in order to evaluate the ability of the microcapsules in protecting chia oil from deterioration. Texture, color, water sorption isotherms, and sensorial properties were also evaluated. A hot homogenization technique was used with carnauba wax as an encapsulant, and the freeze-dried microparticles were incorporated into the cookie dough. Principal component analyses were carried out to evaluate lipid oxidation using the medium infrared spectra of the lipid fraction extracted from the baked cookies. It was found that the microencapsulated chia oil was better protected from oxidative deterioration during baking compared to the sample containing non-encapsulated chia oil. Textural analysis showed that chia oil (free and microencapsulated) acted as a coating on the wheat flour particles. Control cookies (no chia oil loaded) presented a more hydrophilic character. In the case of oil-loaded samples (free and microencapsulated), the isosteric heat of sorption behavior indicated an initial swelling step of the food polymers, resulting in the exposure of sorption sites of higher binding energies not previously available, and that this is because of the wheat particles being covered by the chia oil and the solid lipid microparticles. Furthermore, food acceptability did not change when the oil-loaded microparticles were added to the cookie formulation.     

家蚕蛹油对大鼠肝脏脂质代谢及相关酶活性的影响

以不饱和脂肪酸含量达68%的家蚕蛹油为原料,喂食正常大鼠和高脂模型大鼠,检测大鼠肝脏总胆固醇、甘油三酯、高密度脂蛋白胆固醇、丙二醛浓度及脂蛋白脂酶和肝脂酶活性,研究蚕蛹油对大鼠肝脏脂质代谢及其相关酶活性的影响。结果表明：家蚕蛹油能显著降低大鼠肝脏组织总胆固醇、甘油三酯的含量,增加高密度脂蛋白胆固醇含量,降低肝脏致动脉粥样硬化指数和脂质过氧化产物丙二醛含量;显著提高脂蛋白脂酶和肝脂酶活性。上述结果说明家蚕蛹油具有调节大鼠肝脏脂质代谢、降低血脂的功效。     

Effect of Relative Humidity on the Oxidative Stability of Microencapsulated Sea Buckthorn Seed Oil

ABSTRACT: The effect of relative humidity (RH) (20 °C: RH 11%, 54%) on oxidative stability microencapsulated sea buckthorn seed oil was studied using bulk oil as a reference. Microcapsules were prepared by spray-drying using maltodextrin-gum arabic (MD/GA) and corn starch sodium octenyl succinate derivate (HiCap) as the wall materials. The influence of the physical state of the wall material was also evaluated. Under dry conditions, the microencapsulated oils were most stable, but the oxidation of the bulk oil was accelerated. At 20 °C and at RH 11%, the peroxide value of the bulk oil exceeded 20 meq/kg within 1 wk. Microencapsulation prolonged the shelf-life of the oil from 1 wk to 2 mo at 20 °C, when the encapsulating matrix was in glassy state. In conditions in which the HiCap matrix was in a rubbery state (RH 54%, 20 °C), the oxidation proceeded very quickly, reaching a peroxide value of 20 meq/kg just after 1 wk. Caking and collapse of the microcapsule powder were observed in the rubbery state. At accelerated conditions (50 °C: RH 11%, 30%, 45%), the oxidation was noticeably fast, not only in the bulk oil but also in the MD/GA matrix, even in the glassy state. The behavior in the HiCap matrix was more complex as the amount of peroxides started to decrease in time. This was assigned to the structural collapse in HiCap microcapsules. The behavior of the microencapsulated oils under accelerated conditions did not correlate with their behavior at 20 °C.     

The effect of honey compared to sucrose, mixed sugars, and a sugar-free diet on weight gain in young rats

ABSTRACT:  To determine whether honey, sucrose, and mixed sugars as in honey have different effects on weight gain, 40 6-wk-old Sprague-Dawley rats were fed a powdered diet that was either sugar free or contained 8% sucrose, 8% mixed sugars as in honey, or 10% honey freely for 6 wk. Weight gain and food intake were assessed weekly, and at completion of the study blood samples were removed for measurement of blood sugar (HbA1c) and a fasting lipid profile. The animals were then minced and total percentage body fat and protein measured. Overall percentage weight gain was significantly lower in honey-fed rats than those fed sucrose or mixed sugars, despite a similar food intake. Weight gains were comparable for rats fed honey and a sugar free diet although food intake was significantly higher in honey-fed rats. HbA1c and triglyceride levels were significantly higher in all sugar treatments compared with rats fed a sugar free diet, but no other differences in lipid profiles were reported. No differences in percentage body fat or protein levels were reported.