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Abstract Probiotics in ale beer may be attractive to health-conscious consumers. However, beer conditions may decrease probiotic viability. Powder produced from durian (Durio zibethinus) rind, a by-product that is currently unutilized, can be used for the immobilization of probiotics. MRS medium was incubated with Lactobacillus brevis and periodically sampled to obtain the growth curve. Ale beer with free L. brevis and cells immobilized in durian rind powder was produced and separately assessed during storage at 21 °C for 24 days. The physico-chemical parameters of both beers did not differ significantly. Durian rind powder conferred protection up to 12 days of storage with the immobilized cells in the beer having a significantly higher count than the free cells, which can be due to the acid detergent fiber content (19.67%). Free and immobilized cells remained viable with counts of 4.89 and 5.00 log CFU/mL of beer, respectively, at the end of the storage period. Both treatments had approximate counts of 5 log CFU/mL after 120 min in simulated gastric and intestinal fluids. The predominant bacterial species present at the end of storage were L. brevis and L. farciminis. This study suggests that ale beer could be a potential delivery system for free and immobilized probiotic bacteria. This is one of the few studies demonstrating the use of probiotic lactic acid bacteria in beer brewing. Graphical abstract

The objective of this study was to assess the performance of fermentation media containing egg white hydrolysates (EWH) and/or dried egg white (DEW) with standard MRS media on the growth of lactic acid bacteria (LAB) Lactobacillus plantarum NRRL B-4496, L. acidophilus NRRL B-449, and L. reuteri B-14171. Four fermentation media for growing LAB were evaluated: (1) standard MRS media, (2) MRS with no nitrogen source (MRSN), (3) MRSN with EWH (MRSN-EWH), and (4) MRSN with DEW (MRSN-DEW). The fermentation media were incubated with LAB at 37 °C for 24 h and periodically sampled to obtain growth curves, pH, and titratable acidity. The results showed that EWH had higher amounts of free amino acids compared to DEW. Threonine and leucine were the predominant free amino acids found in EWH. MRSN-EWH was better at promoting the growth of L. acidophilus NRRL B-449 and L. reuteri B-14171 in terms biomass production, maximum growth rate and titratable acidity than MRS. MRS and MRSN-EWH media supported greater cell biomass yields than MRSN and MRSN-DEW for L. plantarum NRRL B-4496. This study showed that egg white hydrolysates can be used in fermentation media to enhance the growth of probiotic lactic acid bacteria.

Growth performance and immune systems of tilapias could be improved by Lactobacillus rhamnosus GG (LGG) and Jerusalem artichoke. This research aimed to determine the effects of Jerusalem artichoke on LGG viability after drying and pelleting and their subsequent exposure to simulated gastrointestinal conditions. Fresh LGG cells were added into wall material solutions, including alginate (AL), alginate + milk powder (AM), and alginate + milk powder + Jerusalem artichoke at different concentrations (AMJ). The solutions were then spray dried to obtain LGG powders. The powder with the highest cell number was then selected to mix with tilapia feed mash and pelleted using a nonthermal feed extruder to obtain pelleted feed containing LGG and Jerusalem artichoke. The LGG viability spray dried powders and pelleted feed were analyzed for their cell counts after drying and after exposure to simulated gastrointestinal conditions. The result showed that the number of viable cells in AMJ was significantly higher than AM and AL after drying. The number of viable cells under both simulated gastric and bile salt fluids was improved with the increasing of Jerusalem artichoke concentrations. The number of viable cells after pelleting process could be maintained. LGG in the pelleted feed could also survive under the simulated gastric and bile salt conditions. The study indicates that JA enhanced LGG viability after drying and exposure to simulated gastrointestinal conditions. The pelleted feed containing LGG and Jerusalem artichoke could be applied in tilapia farming, providing convenience to the farmers, and valuable effects to the fish.

Abstract Undersized crawfish have little economic value and are often discarded. Producing crawfish minced meat (CMM) from undersized crawfish and using an appropriate freezing technique may enable an economically viable market. The objective of this research was to evaluate the effect of the energy removal rate using two techniques, cryogenic freezing (CF) and air blast freezing (BF), on CMM’s quality during frozen storage. CMM was separated into two batches; one batch was cryogenically frozen with liquid nitrogen and the other batch was frozen with an air blast freezer. CMM batches were frozen and stored at − 18 °C. They were analyzed for moisture content, color, pH, and lipid oxidation during 180 days of storage. The CMM yield was 64.67% of the total crawfish weight. Cryogenic freezing achieved the highest freezing rate. Cryogenically frozen CMM showed 22% less lipid oxidation than CMM frozen by air blast freezing at 180 days of storage. This study showed that CMM could be mechanically produced from undersized crawfish and freezing techniques with high energy removal rate could better maintain quality attributes for CMM during frozen storage. Graphical abstract

Bacteriocins produced by lactic acid bacteria may reduce pathogenic loads on cantaloupe surfaces. The efficacy of these bacteriocins on reducing the pathogenic loads of Listeria was evaluated. Non-pathogenic bacteria, Listeria innocua NRRL B-33016 was used as a surrogate for L. monocytogenes. Two bacteriocins, (1) nisin and (2) pediocin, were produced from Lactococcus lactis subsp. lactis ATCC 11454 and Pediococcus acidilactici RS2, respectively. L. innocua NRRL B-33016 was inoculated on the cantaloupes surface at a concentration of 4.69 ± 0.37 log CFU/cm2, and then the melons were stored for 16 days at 4 °C. The antimicrobial activity on L. innocua of the powders was 3.34 × 107 and 1.01 × 108 international units (IU)/g, respectively. Application of nisin freeze-dried bacteriocin-containing powder (NBP), pediocin freeze-dried bacteriocin-containing powder (PBP), or the combination of pediocin-nisin freeze-dried bacteriocin-containing powder (PNBP) significantly reduced L. innocua on the cantaloupes by approximately 1.29, 1.09, and 1.68 log CFU/cm2, respectively. Compared to the controls, bacteriocin applications significantly reduced APC, yeast, and mold counts regardless of bacteriocin type. This study demonstrated that bacteriocins could reduce Listeria, aerobic bacteria, yeast, and mold counts on the cantaloupes surface; and that PNBP was more effective in reducing Listeria than NBP or PBP alone.

Probiotics are commonly added to dairy foods, but due to intolerances and allergies associated with dairy consumption there has been a growing interest in alternative delivery systems. Thus, the viability of Lactobacillus plantarum NCIMB 8826 in a non-alcoholic lactic acid fermented apple juice during 15 d of storage at 4 °C when exposed to simulated gastric and intestinal conditions was evaluated. Tests were conducted on apple juice containing free L. plantarum cells or cells that were immobilized on pectin and added to the juice. During fermentation, the viability of free cells decreased to 7.44 log CFU/mL and the immobilized cells increased to 8.05 log CFU/mL. A decline was observed in the pH and °Brix of the juices with free and immobilized cells, while the lactic acid content increased. All samples except for the juice with free cells at 0 d of storage maintained more than 107 viable CFU/mL when exposed to simulated gastric and intestinal conditions. Fermented apple juice containing immobilized cells during 15 d of refrigerated storage can be used as a functional food for consumers desiring non-dairy probiotic beverages.

The aim of this study was to evaluate the effect of chitosan application method on refrigerated catfish fillet quality. Chitosan solution was prepared by dissolving a medium molecular weight chitosan (0.5%) in 1% acetic acid solution. Chitosan solution was applied to the fillets using three techniques: (1) spraying (15 mL of chitosan solution per 100 g catfish fillets), (2) dipping for 10 min at a 1:1 ratio (w/v), and (3) vacuum tumbling for 10 min at a 1:1 ratio (w/v). After application of chitosan, the fresh catfish fillets were kept under refrigerated storage (4 °C) for 16 days. The fillets were analyzed for solution pick up, pH, aerobic plate counts (APC), lipid oxidation, total volatile nitrogen (TVB-N), color, and texture. Based on aerobic plate counts and total volatile basic nitrogen analysis, catfish fillets that were vacuum tumbled with chitosan solution had an eight-day shelf life increase and sprayed or dipped fillets had four day increases compared to untreated fillets. This study suggests that vacuum tumbling with chitosan solution can deter the proliferation of aerobic bacteria in catfish fillets under refrigerated storage.

Blueberries are a widely consumed fruit known for their high antioxidant content. Due to their short shelf life at refrigerated temperatures, they can be frozen or dried to overcome perishability limitations. Liquid nitrogen pretreatment may be able to increase the permeability of blueberries’ skin, thereby amplifying the effects of osmotic dehydration through increased transfer of moisture and solids. This study evaluated the effects of liquid nitrogen pretreatment on osmotic dehydration and the resulting physicochemical properties of cryogenically frozen blueberries. Blueberries were immersed in liquid nitrogen (− 196 °C) for 10 s and then thawed. Pretreated and un-pretreated samples were placed in a 60°Brix sucrose solution (40 °C) for 8 h, followed by cryogenic freezing. Liquid nitrogen pretreated blueberries experienced greater moisture loss and solids gain than un-pretreated samples after osmotic dehydration, while having similar anthocyanin and total phenolic contents. This study demonstrated that liquid nitrogen pretreatment facilitates water and sugar diffusion in blueberries during osmotic dehydration while maintaining nutritional quality.

The objectives of this study were to produce water-soluble chitosan (WSC) powder and to evaluate the effect of WSC on the survival of Listeria innocua inoculated onto shrimp surfaces. WSC powder was produced using a combination of enzymatic hydrolysis, ultrafiltration, and freeze drying. WSC solutions of 0.5, 1, 3, and 5 g/100 mL concentrations were prepared by dissolving the WSC powder in water. All concentrations of the WSC solutions showed anti-L. innocua activity in vitro, with the 5 g/100 mL WSC solution reducing initial L. innocua counts by 7.43 log CFU/mL. Freshly acquired shrimp were inoculated with L. innocua to an initial concentration of 7.65 log CFU/g. The inoculated shrimp samples were separately dipped in water (control) and in the WSC solutions for 1 min. After dipping in deionized water and 0.5, 1, 3, and 5 g/100 mL WSC solutions, the L. innocua counts were reduced by 1.50, 1.99, 2.25, 3.56, and 5.34 log CFU/g, respectively. For aerobic bacteria loads (8.43 log CFU/g) including L. innocua and natural shrimp microflora, dipping in deionized water and 0.5, 1, 3, and 5 g/100 mL WSC solution resulted in 0, 0.69, 3.21, 3.71, and 4.43 log CFU/g reductions, respectively. This study demonstrated that a low viscosity (0.01–0.29 Pa s) WSC solution could be used as an antimicrobial agent to reduce microbial loads on the surface of shrimp.

The objectives of this study were to evaluate the spray drying conditions to produce Lactobacillus plantarum powders and to investigate their viability at different storage conditions. L. plantarum...

Fortification of queso blanco (QB) with flaxseed oil (FO) containing omega-3 polyunsaturated fatty acids may provide a functional food with health benefits such as improved cell, brain, and retina functionality, and protection against cardiovascular and immune-inflammatory diseases. However, QB experiences a short shelf life because of the early development of yeasts and molds and addition of FO may increase susceptibility to lipid oxidation. Oregano essential oil (OEO) is known for its antimicrobial and antioxidant properties, but due to its intense flavor compounds it may not be suitable for direct incorporation into QB. Thus, incorporation of OEO into an edible film prepared with whey protein isolate (WPI) may improve the shelf life of QB. Scanning electron microscopy (SEM) micrographs revealed that FO was successfully retained by the cheese after homogenization. The thiobarbituric-acid-reactive-substances (TBARS) and yeast and mold counts (YMC) of the wrapped cheeses were analyzed during 60 d of refrigerated storage. The oxidation rate increased significantly for nonwrapped QB containing FO (QBFO) during storage, however wrapping with WPI edible films containing OEO (WOF) significantly limited lipid oxidation and prevented growth of yeasts and molds. This study demonstrated the antioxidant and antimicrobial properties of WOF for preservation of QBFO during refrigerated storage.

Rice is typically stored in the form of whole kernel (rough rice with husk) to minimize quality changes, although storage of milled rice is more convenient and economically feasible. Expenses associated with low temperature storage of rough rice have prompted the need for alternative processing and storage methods, especially in developing countries. Thus, the effects of temperature (30–60 °C) on quality characteristics of milled Catahoula rice during 31 d of storage were investigated. Additionally, the physicochemical properties and cooking quality of rice milled at different intensities (light, medium, and heavy milling) were analyzed. Storage temperature and milling intensity were found to affect the quality of stored and cooked rice, respectively. Higher levels of rice milling intensity correlated with greater water absorption, easier compression, and faster gelatinization of the cooked kernels. During the storage time, protein contents were consistent, while lipid contents slightly decreased. The milled rice experienced an increase in lightness and decrease in moisture content with increasing storage temperatures. This study revealed that by adjusting rice milling parameters and storage temperature the quality of Catahoula rice can be controlled.

A chitosan-sodium tripolyphosphate (CH-TPP) nanoparticle solution was developed and applied to shrimp through vacuum tumbling, and the quality characteristics during frozen storage were evaluated. Four solutions were prepared: (1) a 1% acetic acid (AA) solution, (2) a 0.5% chitosan (CH) solution in the 1% AA solution, (3) a 0.167% sodium tripolyphosphate (TPP) solution in the 1% AA solution, and (4) a CH-TPP solution, prepared by adding 0.167% TPP to the CH solution. Shrimp meat was separately vacuum tumbled with the solutions, cryogenically frozen, and evaluated for quality characteristics during 120 days of frozen storage (−20 °C). Shrimp meat vacuum tumbled with distilled water and shrimp meat without vacuum tumbling were used as controls. CH and CH-TPP treated shrimp had lower aerobic plate counts compared to other treatments during the entire storage time. CH and CH-TPP treated shrimp retained their color, texture, and moisture contents. CH and CH-TPP treatments generated the highest reduction in lipid oxidation compared to other treatments at 120 days of storage at −20 °C. This study showed that a CH or CH-TPP solution combined with vacuum tumbling was effective at reducing aerobic plate counts and lipid oxidation in shrimp during frozen storage while maintaining desired physicochemical properties.

Water-soluble chitosan produced using chitosanase enzyme was characterized and then applied to shrimp through vacuum tumbling. Untreated shrimp meat and shrimp meat treated with acetic acid solution and distilled water through vacuum tumbling were used as controls. All the shrimp were separately cryogenically frozen before frozen storage at −20 °C. The effect of water-soluble chitosan on the shrimp meat quality was evaluated during 120 days of frozen storage. Chitosanase enzyme shortened the polymer chain, reduced the molecular weight and particle size, and markedly improved water solubility of chitosan. Microscopy images showed that water-soluble chitosan penetrated into shrimp muscle tissue while chitosan was adhered on the surface of shrimp. At 120 days of storage, shrimp treated with water-soluble chitosan had lower aerobic plate counts, yeast and mold counts, and lipid oxidation compared to the controls. Also, there were no changes in color, texture, and moisture contents for water-soluble chitosan treated shrimp during frozen storage. Our results showed that chitosanase could process chitosan into water-soluble chitosan with a lower molecular weight and particle size. Our study also demonstrated that water-soluble chitosan could be applied to shrimp through vacuum tumbling for maintaining the quality characteristics of shrimp.

Three protective agents, maltodextrin, wheat dextrin soluble fiber, and hi-maize starch were separately incorporated into pectin-rice bran capsules prepared by ionotropic gelation and loaded with Lactobacillus plantarum. Capsules were then coated with whey protein isolate and freeze dried. Capsules that were not coated were used as controls. The viability of encapsulated cells in the freeze dried capsules was evaluated after freeze drying and at simulated gastrointestinal conditions. The whey protein isolate coating significantly enhanced viability of the encapsulated cells after the freeze drying. The freeze dried capsules with hi-maize starch (FHMC) had the highest cell viability, 8.63±0.01 and 5.63±0.02 log CFU/g for the coated and uncoated capsules, respectively. In simulated gastrointestinal conditions, only 0.89 and 2.12 log cycles were reduced, when the encapsulated cells of FHMC were exposed to fed state with a copious meal (at pH 3.0, followed by pH 7.0) and with a standard meal (at pH 2.5, followed by pH 6.5) condition, respectively. Due to the effect of pH 1.8, low numbers of viable cells were recovered from FHMC (3.27±0.13 log CFU/g) after incubating in a fasted state without meal, while there was no cell survival found in other treatments.

Abstract The objectives of this study were to develop a probiotic milk powder containing Lactobacillus plantarum NCIMB 8826 immobilized with prebiotic Hi-maize starch and to analyze cell viability after spray drying and exposure to simulated gastric and intestinal conditions. Milk powders containing free L. plantarum and cells immobilized with Hi-maize starch were assessed. Powders were evaluated during storage at 4 °C for 15 days. After spray drying, at 0 and 15 days of storage both treatments had over 8 log CFU/g of viable cells and there were higher viable counts found for immobilized cells compared to free cells after 120 min in simulated gastric fluid. At 15 days of storage, immobilized cells had higher viable counts than free cells after exposure to simulated intestinal fluid for 120 min. The combined probiotic and prebiotic milk powder had stable viable cell counts at refrigerated storage conditions and under simulated gastric and intestinal transit. Graphical abstract

Both gelatin and pectin have the ability to trap salt and facilitate its release under simulated gastric conditions. The objective of this study was to develop a pectin-gelatin gel fortified with oral rehydration solution/s (ORS) that can maintain a more rigid structure to limit salt mobility (potentially less salty taste), yet allow rapid release in simulated gastric conditions. Two gels containing both pectin and gelatin were developed: (1) low salt (LS) containing 2.6 g/L salt and 13.5 g/L sugar and (2) high salt (HS) containing 5.2 g/L salt and 27.0 g/L sugar. The ORS-fortified gels were compared with commercially available gelatin gels and a control pectin-gelatin gel without added salt or sugar. A stronger gel network (higher G′) and higher viscosity was noted for HS compared to other samples. HS had slower salt release (80.70 ± 1.92%) than LS (95.95 ± 3.82%) at 1 min in simulated gastric conditions. After 120 min, HS showed up to 99.38 ± 1.08% release of salt, while LS had 95.95 ± 3.82% release. HS had a favorable textural profile, having values more similar to the ready-to-eat commercial cup gel than did the LS formulation. The HS formulation resulted in a stable structure for ORS delivery and beneficial release properties.

Kombucha is produced with a symbiotic culture of bacteria and yeast (SCOBY). Sugared coffee has potential as a fermentation substrate for kombucha production. Objectives of this study were to: (1) produce coffee kombucha (CK) with Lactobacillus rhamnosus (LG) and Lactobacillus casei (LC) and characterize its microbial diversity, (2) evaluate the physicochemical properties and determine viability of CK inoculums under simulated gastric and intestinal conditions during refrigerated storage. Coffee was fermented for 8 days at 23 °C. LG and LC were inoculated into CK (5% v/v) and stored for 15 days at 4 °C. Acetobacteraceae were predominant for the control and Lactobacillaceae for both treatments after 15 days. CK with LG or LC stored for 15 days had 7.44 and 8.77 log CFU/mL, respectively, after exposure to simulated gastric and intestinal conditions. The DNA sequencing analysis revealed that the addition of LG and LC to the CK shifted the proportion of microbial families from Acetobacteraceae to Lactobacillaceae. This study suggests that added Lactobacilli can subsist in CK for 15 days and survived simulated gastrointestinal transit.

Three cereal-legume complementary foods (weanimix) were formulated and evaluated for their ability to enhance the survival of probiotic bacteria Lactobacillus plantarum NCIMB 8826 in simulated gastrointestinal tract conditions. The three different blends of weanimix: MCPPM (maize:cowpea:peanut:powdered milk), MCP (maize:cowpea:peanut) and MC (maize:cowpea) were used. L. plantarum was inoculated and cultured in the weanimix slurry media to immobilize the cells. L. plantarum free cells in MRS broth were used as a control. Simulated gastric fluid (SGF) of pH 2.5, 3.0 and 3.5, and bile salt (0.3 and 1 g/100 ml of ox gall) were used to simulate the gastrointestinal conditions. The three complementary blends offered a protective shield, which improved cell viability in SGF at all pH levels. L. plantarum survived well in MCPPM, MCP and MC with

Chitosan (CH) and chitosan-sodium tripolyphosphate (CH-TPP) solutions were produced with and without sonication and ultra-shearing. The CH and CH-TPP particles and solutions were evaluated for physicochemical properties, and fluorescently labeled particle penetration into shrimp muscle tissue through vacuum tumbling was observed. Two solutions were prepared: (1) a 0.5 % CH solution in 1 % acetic acid and (2) a CH-TPP solution, prepared by adding 0.167 % sodium tripolyphosphate to the CH solution, instantly forming CH-TPP nanoparticles through ionotropic gelation. Untreated shrimp meat and shrimp meat vacuum tumbled with CH, CH-TPP, acetic acid, sodium tripolyphosphate, and distilled water solutions were analyzed for aerobic plate counts for 24 days of refrigerated storage at 4 °C. Processing with sonication and ultra-shearing reduced the particle sizes of CH and CH-TPP nanoparticles and the molecular weight of CH. It was observed that after processing, fluorescently labeled CH and CH-TPP nanoparticles could penetrate inside of and attach to shrimp muscle tissues through vacuum tumbling. At 24 days of refrigerated storage, shrimp vacuum tumbled with processed CH solution had the lowest aerobic plate counts of all treatments and it was the only treatment to have unchanged microbial quality throughout the entire storage time. Vacuum tumbling with sonicated and ultra-sheared CH solution enhanced particle penetration into shrimp and inhibited microbial growth during refrigerated storage.

The aim of this study was to evaluate the effect of microencapsulation of ginger (Zingiber officinale Roscoe) extract using maltodextrin (MD) and/or gum arabic (GA) as microencapsulation agents on its 6-gingerol content, total phenolic and antioxidant activity. Four slurries containing 95 mL/100 mL of ginger extract (2 g solids/100 mL) and 5 g/100 mL of a blend of maltodextrin:gum arabic of weight ratios (4:1, 1:4, 5:0, and 0:5 g:g) were prepared and they were separately spray dried at 160 °C inlet air temperature to produce ginger extract powders. Ginger extract contained 20.6 ± 0.2 (mg/g solids) 6-gingerol, 7.7 ± 0.6 (mg/g solids) gallic acid equivalents and had an antioxidant activity of 19.9 ± 0.8 (μmol Trolox/g solids). Microencapsulation resulted in a decline in the quantity of 6-gingerol present in ginger extract regardless of the maltodextrin and gum arabic blend. Microencapsulation of ginger extract also reduced gallic acid equivalents and antioxidant activity. Ginger extract dried with maltodextrin:gum arabic (1:4 g:g) and (0:5 g:g) had larger particle size than that dried with maltodextrin:gum arabic (4:1 g:g) and (5:0 g:g). Maltodextrin:gum arabic (4:1 g:g) and (5:0 g:g) had better morphological properties than maltodextrin:gum arabic (4:1 g:g) and (5:0 g:g). Microencapsulated ginger extract powder may be used as a novel food ingredient.

Alpha-tocopherol (α-TOC) has low stability, poor water solubility, and variable bioavailability that could limit its application in food products. In this study, α-TOC was entrapped in nanofibers and films containing soluble dietary fiber (SDF) to protect the compound from undesirable conditions and maintain its bioactivity. The stability of α-TOC in soluble dietary fiber (SDF) based nanofiber (SDF-nanofibers) and film (SDF-film) was investigated after exposure to heat and UV irradiation, as well as during storage at room temperature. It was found that retention of α-TOC in SDF-nanofibers and SDF-film was higher (p

A combined pectin-rice bran delivery system for Lactobacillus plantarum NRRL-B4496 (LP) was developed. Four pectin (PE)-rice bran extract (RB) gel solutions were prepared: (1) 2.0 g/100 mL PE with 0.5 g/100 mL RB, (2) 2.0 g/100 mL PE with 1.0 g/100 mL RB, (3) 2.0 g/100 mL PE with 2.0 g/100 mL RB, and (4) 2.0 g/100 mL PE (control). L. plantarum was grown in MRS broth, centrifuged, and mixed with the gel solutions. The capsules loaded with L. plantarum (LP/PE-RB capsules) were then prepared by ionotropic gelation. PE-RB gel solutions exhibited pseudoplastic behavior. The gel solution containing 2.0 g/100 mL RB had the highest consistency and viscosity. All LP/PE-RB capsules had similar diameter size. Both the sphericity and the encapsulation efficiency of the capsules were increased with higher RB content, while the hardness and springiness were decreased. When exposed to acidic and bile salt conditions, the viability of encapsulated cells was higher than free cells. The study demonstrated that pectin-rice bran capsules could have potential as a delivery system for L. plantarum.

The effect of alpha-tocopherol (α-TOC) delivered by soluble dietary fibre-based nanofibres (α-TOC-SDNF) on the life span of nematode Caenorhabditis elegans N2 (wild type) and TK22 (mev-1 mutants) with and without heat shock was investigated. Without heat shock, the wild-type and mev-1 mutants maintained in the 100 µg/mL of α-TOC-SDNF had longer life spans than their respective blank control groups. With heat shock, the wild-type N2 in the 200 µg/mL of α-TOC-SDNF had a survival rate of 5% at day 49, while no nematodes survived in the blank control group. An increased pharyngeal pumping rate was observed in the α-TOC-SDNF treated mev-1 mutants worms compared to the blank control group. Encapsulating α-TOC in SDNF yielded protective effects and the life span and pumping rate of C. elegans was increased with α-TOC delivered by SDNF.

This study evaluated the effect of bambara groundnut supplementation on the physicochemical properties of local rice flour and baked crackers. Bulk and true density, porosity, water absorption index, oil absorption capacity, pasting properties by RVA, morphological appearance by SEM, color by calorimetry, and textural properties by TA.XT2 analysis of wheat and two formulations of rice-legume flours and crackers were studied. Moisture (10.94%) and carbohydrate (77.42%) levels were significantly greater in wheat flour than the rice-legume flours, while the reverse was true for fat and ash. Also rice-legume flours had significantly greater water and oil absorption capacity and lower water solubility compared to wheat flour. Compared to wheat crackers, rice-legume crackers had greater fat and ash, 20.51 and 3.57%, respectively, while moisture was significantly lower in the rice-legume crackers by 41 to 58%. Rice legume crackers were significantly harder and had significantly increased spread ratio. The results obtained from the development of locally grown rice and underutilized legume bambara groundnut showed great promise in physicochemical and functional properties and may be a good replacement for wheat flour to serve as a gluten-free product.

The objectives of this study were to develop and evaluate a frozen yogurt (FY) fortified with a nano-emulsion containing purple rice bran oil (NPRBO). NPRBO with fat droplets size range of 150–300 nm was mixed with the FY ingredients to produce a frozen yogurt containing NPRBO (FYNRO). Plain frozen yogurt (PFY), frozen yogurt with sodium caseinate (FYSC) and FYNRO had similar hardness. The apparent viscosity of the FYNRO mix was similar to the PFY mix with values of 0.19 and 0.17 Pa·s, respectively. The FYNRO micrograph showed a more compact and dense structure compared to FYSC and PFY. This study demonstrated that FY could be fortified with NPRBO.

Blueberries have received considerable attention due to their content of health promoting compounds such as polyphenols and anthocyanins. Thermal processing is known to cause degradation of anthocyanins and juice color. The objectives of this research were to study the effect of continuous ultrasonication processing on the microbiological, chemical and physical properties of blueberry juice (BJ). Unpasteurized BJ was pumped at 24 mL/min or 93.5 mL/min to the continuous flow cell of an ultrasonic processor, where it was sonicated at three treatment levels, 13.88 ± 2.45, 43.45 ± 4.12, and 73.60 ± 5.35 (J/mL) energy density. Sonicated and unsonicated juices were analyzed for coliforms, total aerobes, yeasts and molds. Total anthocyanin content, total phenol content, antioxidant activity, °Brix, titratable acidity, pH and color were also determined for both sonicated and unsonicated juices. Continuous flow sonication successfully reduced microbial counts. Sonication at higher intensities significantly (p

This study investigated purple rice bran fiber (PRF) as a protectant for Lactobacillus plantarum NRRL B-4496 (LP) during freezing, freeze drying and storage. PRF was enzymatically extracted from purple rice bran. L. plantarum NRRL B-4496 was grown in MRS broth, centrifuged, and immobilized on PRF suspension. LP cells immobilized on PRF (LP-PRF) and free LP cell (control) samples were frozen in either air blast (AF) or cryogenic freezing (CF) before freeze drying. Freeze-dried (FLP) samples were stored either at room temperature or at refrigerated temperature. For either freezing method, PRF protected cells had less than one log reduction of viable cells while the control had reductions greater than six logs after freeze drying. The log reductions of viable LP cells protected with PRF after freeze drying and 12 weeks storage at 4° C for AF and CF treatments were 0.7 and 1.3 log cycle, respectively. The viable LP-PRF cell count for CF was significantly lower than for AF after 12 weeks at room temperature. PRF improved LP survival in both AF and CF samples in bile. This study demonstrated that freezing methods affected LP viability during storage and that PRF could protect at both refrigerated and room temperatures.

This study investigated the effect of blueberry juice on menhaden oil lipid oxidation during microencapsulation. Oil in water emulsions containing menhaden oil with 0, 5, or 10% blueberry juice were spray dried to produce control-M, 5% BJ-M, and 10% BJ-M microencapsulated powders, respectively. All microencapsulated powders had similar encapsulation efficiencies with low surface oil content. Peroxide value (meq/kg of oil) was 4.50, 4.31, and 3.38 for control-M, 5% BJ-M and 10% BJ-M, respectively. Ten percent BJ-M had lower (P < 0.05) anisidine value, and totox values than 5% BJ-M and control-M. This indicated that 10% blueberry juice reduced lipid oxidation in menhaden oil during microencapsulation to a greater extent than the other formulations.

The potential of chitosan (CH) combined with sodium tripolyphosphate (TPP) nanoparticles as a glazing material for shrimp was investigated. Two CH–TPP nanoparticles glazing solutions were prepared: (1). A solution containing CH–TPP nanoparticles with 0.25 (g/100 mL) CH and 0.083 (g/100 mL) TPP (25CH–TPP) and (2). A solution containing CH–TPP nanoparticles with 0.5 (g/100 mL) CH and 0.167 (g/100 mL) TPP (50CH–TPP). Frozen shrimp samples were glazed with 25CH–TPP, 50CH–TPP, CH, TPP, acetic acid, and/or distilled water and then stored at −21 °C for 30 days. Glazed and non-glazed shrimp (NG) samples were analyzed for moisture content, glazing yield, weight loss, color, cutting force, thiobarbituric acid reactive substances (TBARS), yeasts, molds, coliforms and aerobic counts after 1, 3, 5, 20, and 30 d storage. Triplicate experiments were conducted and data statistically analyzed ( α = 0.05). Glazed shrimp had higher moisture than NG after 30 d storage. Among the glazes, 25CH–TPP and 50CH–TPP were the most effective in controlling lipid oxidation and reducing aerobic counts and yeasts and molds in shrimp.

Tomato is highly perishable and drying is a convenient method of extending its shelf life and minimizing postharvest loses. During drying, some nutrients may degrade and thus affect general quality characteristics of the dried tomato. The effect of pretreatment in enhancing drying and product quality of dried tomato was investigated in this study. Slices of tomato were treated by dipping in (a) A solution containing 0.5% sodium metabisulphite for 10 min and (b) 0.1% ascorbic acid + 0.1% citric acid solution for 10 min (1:1) and (c) distilled water for 10 min (control). Convection dehydration was carried out on tomato slices using an electric dehydrator at 55°C for 6 h. Pretreatment of tomato affected some quality attributes such as total solids, lycopene, dehydration ratio, rehydration ratio and colour. Pretreatment with sodium metabisulphite recorded the least lycopene degradation, highest dehydration ratio (19.40 ± 1.03) and also facilitated the drying of tomato better than the other treatments. All the pretreated dried tomato samples produced good visual and exhibited a desirable red colour (a* values ranging between 24.49 ± 0.44-28.34 ± 0.03) which is characteristic of dried tomato products. Pretreatment with sodium metabisulphite before convection drying can enhance the lycopene content which is a desirable quality attribute for dried tomato. Key words: Convection drying, dried tomato, sodium metabisulphite, pretreatment, drying rate, lycopene.

The effect of the addition of blueberry extract (BE) obtained from blueberry pomace on lipid oxidation of pollock liver oil (PO) during microencapsulation was evaluated. An emulsion containing PO and BE (EBE) was prepared and spray dried in a pilot scale spray dryer. Thiobarbituric acids (TBARS) of EBE were lower (0.41 mmol/kg oil) than that of control without BE (ENBE) (0.47 mmol/kg oil). Also, TBARS value of 0.49 mmol/kg oil for microencapsulated PO with BE (MBE) after spray drying was lower than that of microencapsulated PO without BE (MNBE) (0.57 mmol/kg oil). MBE also had a lower TBARS value than that of MNBE after 17 days of storage at 4C and room temperature. This study indicated that BE reduced lipid oxidation of PO during emulsification. It also demonstrated that BE can be successfully used to delay the lipid oxidation during spray drying and storage of PO. Practical Applications Marine fish oils are good sources of eicosapentaenoic acid and docosahexaenoic acid. Blueberry (Vaccinium spp) extract obtained from blueberry pomace contains numerous bioactive compounds such as anthocyanin and soluble dietary fiber, which makes it a potential additive for functional foods. Because of its antioxidant properties, BE may reduce the oxidation of marine fish oils during microencapsulation processes.

Chitosan’s water insolubility restricts its use in some food systems. However, when treated with enzymes, a water-soluble chitosan is developed, which overcomes insolubility. The aim of this study was to evaluate the effect of chitosan and water-soluble chitosan applications on refrigerated catfish fillet quality. Fresh catfish fillets were separately vacuum tumbled with distilled water, 1% acetic acid, chitosan (0.5% in acetic acid), and water-soluble chitosan (0.5% in distilled water). Sampling was done at 0, 5, 10, 15, and 20 days. The fillets were analyzed for lipid oxidation, aerobic plate counts, yeast and mold counts, cutting force, color, and pH. Triplicate experiments were done and the data were statistically analyzed at a significance level of 0.05. Water-soluble chitosan had 86 ± 2% water solubility compared to 1.9 ± 0.2% for chitosan. Fillets treated with water-soluble chitosan solution had lipid oxidation reduced by approximately 70% compared to untreated fillets during 20 days of refrigerated storage. Chitosan treated fillets showed the highest inhibition with aerobic plate, yeast and mold counts. Initially, fillets treated with acetic acid and chitosan solutions had a more rapid decrease in hardness than those vacuum tumbled with water-soluble chitosan and distilled water. Therefore, this study showed both the advantages and limitations of applying chitosan or water-soluble chitosan for preserving catfish fillet quality during refrigerated storage.

The effects of cryogenic and air blast freezing techniques on catfish fillet quality during frozen storage was evaluated. Fresh channel catfish fillets were cryogenically frozen by liquid carbon-dioxide using a pilot plant size cabinet type cryogenic freezer (CF) and by air blast (BF) frozen to −21 °C, separately. Freezing time (FT), freezing rate (FR), and energy removal rate (ERR) for freezing depend on the freezing techniques, which affect energy consumption and frozen seafood quality. The frozen fillets were stored at −20 °C and analyzed for weight loss, relative moisture loss, color, and lipid oxidation (Thiobarbituric acid; TBA) after 1-day, 1-month, 3-months, and 6-months of storage. Triplicate experiments were conducted and data were statistically analyzed at α = 0.05. FT for cryogenic freezing and air blast freezing were 19.3, and 55.1 min, respectively. Cryogenic freezing had higher FR (1.29 °C/min) and ERR (10.62 J/s) than BF (0.46 °C/min and 3.38 J/s, respectively). The cryogenically frozen catfish fillets had a lower freezing loss than fillets frozen by air blast freezing. TBA (mg MDA/kg sample) of the fillets frozen by CF was 0.94 which was lower than BF (1.25). The study demonstrated that catfish fillets cryogenically frozen had better quality characteristics than blast frozen catfish fillets after 6-months of storage.

Carrot juice samples treated with pulsed electric fields (PEF) of electric field intensity of 25 kV/cm and treatment time of 144.6 μs (PEF1) and 433.8 μs (PEF2) and thermal pasteurization (TP) treatment of 90C for 1 min were evaluated for physicochemical properties and microbial inactivation. The PEF1 and PEF2 treated carrot juice retained higher amounts of ascorbic acid, α-carotene, β-carotene and lutein than the TP-treated carrot juice. The PEF-treated carrot juices were not significantly (P > 0.05) different in pH and °Brix compared to the control, while the TP-treated juices were significantly different in °Brix and total acidity compared to the control. The PEF2 was comparable with the TP for inactivation of aerobic bacteria and mold in carrot juice. Practical Applications Pulsed electric field (PEF) can be used as a nonthermal pasteurization method to inactivate microorganisms and enzymes in liquid food and it preserves the physiochemical and sensory properties, and nutritional value of liquid food. Our study showed that PEF treatment was more efficient in preserving some physicochemical and quality properties of carrot juice compared to conventional heat pasteurization.

Fortification of queso blanco (QB) with flaxseed oil (FO) containing omega-3 polyunsaturated fatty acids may provide a functional food with health benefits such as improved cell, brain, and retina functionality, and protection against cardiovascular and immune-inflammatory diseases. However, QB experiences a short shelf life because of the early development of yeasts and molds and addition of FO may increase susceptibility to lipid oxidation. Oregano essential oil (OEO) is known for its antimicrobial and antioxidant properties, but due to its intense flavor compounds it may not be suitable for direct incorporation into QB. Thus, incorporation of OEO into an edible film prepared with whey protein isolate (WPI) may improve the shelf life of QB. Scanning electron microscopy (SEM) micrographs revealed that FO was successfully retained by the cheese after homogenization. The thiobarbituric-acid-reactive-substances (TBARS) and yeast and mold counts (YMC) of the wrapped cheeses were analyzed during 60 d of refrigerated storage. The oxidation rate increased significantly for nonwrapped QB containing FO (QBFO) during storage, however wrapping with WPI edible films containing OEO (WOF) significantly limited lipid oxidation and prevented growth of yeasts and molds. This study demonstrated the antioxidant and antimicrobial properties of WOF for preservation of QBFO during refrigerated storage.

Optimum extraction conditions for extraction of soluble rice bran fiber (SRBF) from defatted rice bran (DRB) were determined using response surface methodology (RSM). The three independent variables for extracting SRBF, including ratio of Ca(OH)2 solution to DRB, concentration of Ca(OH)2 and extraction temperature on the yield of SRBF were determined on the basis of single factor experiments. A Box–Behnken design (BBD) was used to investigate the effects of the three independent variables, and the BBD consisted of 15 experimental points with three replications at the center point. The experimental study examined the effect of the independent variables within the following ranges: Ca(OH)2 solution to DRB ratio range of 25:1–30:1, Ca(OH)2 concentration in the range of 2–3% and the temperature in the range of 20–100C The optimum experimental yield of SRBF (7.86 ± 0.04%) was obtained at the extraction condition of 3% Ca(OH)2 solution with a ratio of solution to DRB of 29.75:1 (mL/g) stirred for 1 h at 84C. The experimental yield percentage was in agreement with predicted yield percentage of SRBF by RSM at the optimum extraction conditions. Practical Applications The optimum soluble rice bran fiber (SRBF) yield cannot be estimated based on just the one-factor-at-a-time (single-factor) approach, because it is not only time consuming, but also the interaction between extractions condition may not be included in the determination of the yield and/or quality. A study is needed not only to determine the optimum extraction conditions to obtain a desirable yield or quality of SRBF from defatted rice bran (DRB) but also to understand the degree of interactions between extraction conditions such as temperature, time, ratio of solvent to raw material and solvent concentration.

Defatted rice bran (DRB), an excellent source of soluble rice bran fiber (SRBF), is a byproduct of rice bran oil extraction from whole rice bran. The common process for purifying SRBF extracted from DRB, dialysis and alcohol precipitation, is a complex process. Ultrafiltration technology was evaluated as an alternative process. Membranes of molecular weight cut-off (MWCO) 1, 5, and 10 kDa were used to purify the SRBF at 100 kPa. The apparent viscosity and °Brix of the SRBF solution increased after ultrafiltration, which demonstrated that the SRBF solution was concentrated during the ultrafiltration process. The apparent viscosity of the retentate collected in the ultrafiltration unit with the 1 kDa MWCO membrane had a higher ( P

The quality of biodiesel from crude pollock oil and the effect of a purification process on the physicochemical properties of pollock oil biodiesel were evaluated. Unpurified pollock oil (PO) was transesterified to biodiesel from pollock oil (BPO) using methyl alcohol (1:6 molar ratio) and NaOH (1 % w/w of the oil weight); and the resulting fatty acids methyl esters (FAME) were purified with 10 % (w/w) activated earth to yield purified biodiesel from pollock oil (PBPO). The samples were evaluated for yield, FAME composition, free fatty acids (FFA), peroxides value (PV), moisture, bulk density, cloud point, flash point, free and total glycerin, color, rheological properties, and minerals. BPO and PBPO were evaluated for the kinetics of lipid oxidation. The transesterification and purification processes had no effect on the FAME composition of PO. The yield of PBPO was significantly (P < 0.05) reduced after the transesterification and purification processes. Moreover, the transesterification process significantly (P < 0.05) reduced the FFA, moisture, bulk density, flash point, total glycerides, redness, viscosity, arsenic and silicon content in PO. Meanwhile, the purification process significantly (P < 0.05) reduced the PV, redness, and sulfur content of BPO. The flash point of BPO was significantly (P < 0.05) increased by the purification process from 79 to 84 °C. PO, BPO, and PBPO behaved as non-Newtonian and Newtonian fluids at 0 and 25 °C, respectively. BPO showed a lower oxidation rate and activation energy compared to those of PBPO. BPO and PBPO met the ASTM biodiesel standard D6751 for moisture, bulk density, cloud point, free and total glycerin, Na, P, and S. The study demonstrated that high viscosity crude pollock oil could be converted into low viscosity purified pollock oil biodiesel.

Cantaloupes are a good source of carotenoids and vitamin C. Cantaloupe fruit juice powder containing vitamin C and β-carotene can be produced by spray drying. The objective of this study was to develop cantaloupe fruit juice (CJ) powder and to evaluate its nutritional and physical properties. Fresh cantaloupe fruits purchased from a local store were diced and juiced. CJ with 10% maltodextrin (MD) added was spray dried at inlet temperatures of 170, 180 and /or 190 °C. Three spray dried cantaloupe powders, including CJ dried with MD at 170 °C (CJP1), CJ dried with MD at 180 °C (CJP2), CJ dried with MD at 190 °C (CJP3) were analyzed for moisture, water activity, vitamin C, β-carotene, dissolution, and microstructure. The actual production rate of the cantaloupe juice powders was lower than the estimated production rate. CJP1 had ( p p