Effects of Air Frying on French Fries: The Indication Role of Physicochemical Properties on the Formation of Maillard Hazards, and the Changes of Starch Digestibility.

This study focused on the formation of Maillard hazards in air fried fries, highlighting the correlation between the resultant physical properties of the fries and the formation of Maillard hazards. In the meantime, the effects of air frying on the in vitro starch digestibility of fries were explored. Potato strips were fried at various temperatures (180-200°C) and time (12-24 min). Results indicated that the extent of browning, hardness, and the contents of Maillard hazards (acrylamide, 5-hydroxymethylfurfural, methylglyoxal, and glyoxal) all increased steadily with air frying temperature and time. Moisture content were negatively correlated (p < 0.001) with Maillard hazards content and physicochemical properties except for L* with the correlation coefficients range from -0.53 to 0.94, and positively correlated with L* value with correlation coefficient was 0.91, hence, reducing the Maillard hazard exposure while maintaining the desired product quality can be achieved by controlling the moisture content of the air fried French fries. Compared with deep frying (180°C-6 min), air frying decreased acrylamide and 5-hydroxymethylfurfural content with the maximum reduction rate were 47.31 and 57.04%, respectively. In addition, the in vitro digestion results suggested that air frying resulted in higher levels of slowly digestible starch (48.54-58.42%) and lower levels of resistant starch (20.08-29.34%) as compared to those from deep frying (45.59 ± 4.89 and 35.22 ± 0.65%, respectively), which might contribute to more balanced blood sugar levels after consumption. Based on the above results, it was concluded that air frying can reduce the formation of food hazards and was relatively healthier.

High Hydrostatic Pressure-Based Combination Strategies for Microbial Inactivation of Food Products: The Cases of Emerging Combination Patterns.

The high demand for fresh-like characteristics of vegetables and fruits (V&F) boosts the industrial implementation of high hydrostatic pressure (HHP), due to its capability to simultaneously maintain original organoleptic characteristics and to achieve preservative effect of the food. However, there remains great challenges for assuring complete microbial inactivation only relying on individual HHP treatments, including pressure-resistant strains and regrowth of injured microbes during the storage process. Traditional HHP-assisted thermal processing may compromise the nutrition and functionalities due to accelerated chemical kinetics under high pressure conditions. This work summarizes the recent advances in HHP-based combination strategies for microbial safety, as exemplified by several emerging non-thermally combined patterns with high inactivation efficiencies. Considerations and requirements about future process design and development of HHP-based combination technologies are also given.

Bioinformatic Analysis Identified Hub Genes Associated with Heterocyclic Amines Induced Cytotoxicity of Peripheral Blood Mononuclear Cells.

Heterocyclic amines (HCAs) are a set of food contaminants that may exert a cytotoxic effect on human peripheral blood mononuclear cells (PBMC). However, the genetic mechanism underlying the cytotoxicity of HCAs on PBMC has not been investigated. In the study, bioinformatic analysis on gene dataset GSE19078 was performed. The results of weighted correlation network analysis and linear models for microarray and RNA-seq data analysis showed that four gene modules were relevant to 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) exposure while one gene module was correlated with 2-amino-3-methyl-3H-imidazo[4,5f]quinoline (IQ) exposure. Gene functional analysis showed that the five modules were annotated mainly with mRNA transcriptional regulation, mitochondrial function, RNA catabolic process, protein targeting, and immune function. Five genes, MIER1, NDUFA4, MLL3, CD53 and CSF3 were recognized as the feature genes for each hub gene network of the corresponding gene module, and the expression of feature genes was observed with a significant difference between the PhIP/IQ samples and the other samples. Our results provide novel genes and promising mechanisms for exploration on the genetic mechanism of HCAs on PBMC.

Reduction of the Heterocyclic Amines in Grilled Beef Patties through the Combination of Thermal Food Processing Techniques without Destroying the Grilling Quality Characteristics.

In order to reduce the formation of heterocyclic amines in grilled beef patties without destroying their unique quality characteristics, the effects of different thermal processes, including charcoal grilling, infrared grilling, superheated steam roasting and microwave heating, on the production of heterocyclic amines in beef patties and grilling quality characteristics were systematically analyzed. The results showed that infrared grilling can significantly (p < 0.05) reduce the content of heterocyclic amines in grilled patties, and the combination of microwave heating or superheated steam roasting with infrared grilling could further reduce the content of heterocyclic amines, with a maximum reduction ratio of 44.48%. While subtle differences may exist in infrared grilled patties with/without superheated steam roasting or microwave heating, a slight change will not affect the overall quality characteristics of grilled patties. The combined thermal processing will not visually affect the color of the grilled patties. Correlation analysis and regression analysis showed that the reduction in heterocyclic amines caused by microwave heating and superheated steam roasting are related to the moisture content and lipid oxidation of grilled patties, respectively. Using combined thermal processes to reduce the formation of heterocyclic amines is advisable.

Promotion Effect of EGCG on the Raised Expression of IL-23 through the Signaling of STAT3-BATF2-c-JUN/ATF2.

Tea polyphenol of epigallocatechin-3-gallate (EGCG) has been verified to possess multiple biological activities. Interleukin-23 (IL-23) is a heterodimeric cytokine consisting of two subunits of IL-23p19 and IL-12p40, with the functionality in regulating the production of cytokines under physiological or pathological conditions. By serendipity, the raised expression of IL-23 was observed after treating cells with EGCG, whereas the detailed mechanism remains poorly understood. This study was proposed to investigate the signaling related to EGCG-induced IL-23. The raised expression of IL-23 was confirmed primarily by intraperitoneally injecting with different concentrations of EGCG (0, 20, 50, 80 mg/kg) into BALB/c mice, and the raised expression was confirmed by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. Results from enzyme-linked immunosorbent assay (ELISA) revealed the increase of IL-23 in serum from 116.09 to 153.90 pg/mL after treating with EGCG. The same results were also observed in RAW264.7 and peritoneal macrophages after treating with EGCG (0, 1, 5, 10, 25 µM) with the increased tendency of IL-23 in cultural medium (7.98 to 25.38 pg/mL for RAW264.7; 3.64 to 260.93 pg/mL for peritoneal macrophages). After preliminary exploration of the signaling related to the increased IL-23, the classical signaling pathways and key transcription factors, such as nuclear factor kappa-B (NF-κB), mitogen-activated protein kinase (MAPK) signaling pathways, and interferon regulatory factor 5 (IRF5), were demonstrated with no relevant contribution. A further study revealed the involvement of the key transcription factor of BATF2, which could antagonistically modulate the transcription and translation of IL-23. The signaling of STAT3-BATF2-c-JUN/ATF2-IL-23 has been further verified in RAW264.7 macrophages using the STAT3 inhibitor of AG490 and the activator of Colivelin TFA. The results indicated that EGCG inhibits the phosphorylation of STAT3 to facilitate the decreased level of BATF2, which contributed to the increased level of IL-23 by the enhancing heterodimerization of c-JUN and ATF2.

Enhanced biotransformation of soybean isoflavone from glycosides to aglycones using solid-state fermentation of soybean with effective microorganisms (EM) strains.

To improve the biotransformation efficacy (BE) of glycosides to aglycones in total soybean isoflavone (SIF), Taguchi experimental design has been used to study the most significant factors on BE of glycosides to aglycones using solid-state fermentation (SSF) of soybean with effective microorganisms (EM) strains. Physicochemical properties of optimized fermented dregs have also been analyzed to evaluate their probiotics count and mainly nutritional parameters. The results showed that identified optimal fermentation conditions are 30°C, 40% water content, 5% inoculation level, 6 d culture time, and 20 mesh number. BE of aglycones reached 85.30% with dry matter recoveries of 96.34% based on optimal fermentation conditions. Total bacterial and lactic acid bacteria count reached 17.98 and 9.34 × 108 CFU/g with decreasing pH (4.21) and an increasing acidity (8.62 g/kg), respectively. This study could provide the theoretical grounds for aglycones biotransformation in large-scale production applied in food and other fields. PRACTICAL APPLICATIONS: Isoflavones widely present in soy products possessing strong antioxidant capacity and estrogen-like activity. In human intestines, aglycone isoflavones after treatment/fermented are absorbed faster than their glucosides in untreated soybeans. The majority of glucoside isoflavones in soybean during fermentation were biologically converted to bioactive aglycone isoflavones via EM strains-fermented ß-glucosidase. SSF of soybean with EM cocultures to ferment soymilk efficiently increased BE of glycosides to aglycones. Hence, EM cocultures as a new functional ingredient could improve the nutritional value of fermented soybean.

Influence of Monascus purpureus BD-M-4 on the physicochemical properties, proteolysis and volatile compounds of surface mould-ripened cheese.

The effect of adjunct culture Monascus purpureus BD-M-4 on the physicochemical, proteolytic, and lipolytic properties of surface mold-ripened cheese were evaluated. During the maturation of Monascus-fermented cheese, the total microbiota count and the content of soluble nitrogen increased steadily, whereas the total protein content showed no significant difference. Moreover, a 17-fold increase in total free amino acids was observed in Monascus-fermented cheese. The use of adjunct culture M. purpureus BD-M-4 in the production of surface-ripened cheeses did not show a significant effect on the total fat content in the ripening period, nor did it change the lipolysis of cheese during ripening. Compared to 52 volatile compounds of the control cheese, a total of 62 compounds were detected in M. purpureus-fermented cheese, including 16 acids, 16 ketones, 11 alcohols, 5 aldehydes, 11 esters, and 3 unclassified compounds.

A novel, sensitive and non-destructive method for quantitative determination of lipid in live Eriocheir sinensis using low-field 1H Nuclear magnetic resonance.

In this study, lipid content of live Eriocheir sinensis has been quickly and accurately determined by low-field 1H Nuclear magnetic resonance (LF-1H NMR). The experimental parameters of LF-1H NMR have been optimized and the validity of the established standard method has been confirmed with traditional Soxhlet extraction method. Results show that the lipid signal intensity is strongly correlated with its content and exhibits a good linear correlation (Y = 0.0376 + 4.899X, R 2 = 0.9999), thus demonstrating favorable accuracy and sensitivity for the quantitative determination of lipid content. In conclusion, the lipid content of live E. Sinensis can be directly obtained based on an established method, indicating a great application potential in food and other fields.

Preparation, characterization and in vitro release of ß-galactosidase loaded polyelectrolyte nanoparticles.

Improving encapsulation efficacy (EE) and bioavailability of ß-galactosidase (ß-gal) is always a challenge due to its fragility. In this work, ß-gal loaded ß-chitosan (CS) nanoparticles (NPs) were successfully prepared based on ionic gelation technique and electrostatic attraction for improving its EE and in vitro releasing capacity. The particle size of ß-gal loaded low and high molecular weight (LMW and HMW) ß-CS NPs reached 584.37 and 652.46nm, with Zeta-potential (ZP) of 26.37 and 16.46mV under the optimal conditions, respectively. In vitro release study conducted at pH4.5 and 7.4 showed that ß-gal loaded LMW and HMW ß-CS NPs with EE of 68.32 and 58.64% sustained the release of the ß-gal over 12h. The ß-gal incorporated into ß-CS NPs was confirmed with the results of physicochemical and structural properties of ß-gal loaded ß-CS NPs, and prepared NPs had hardly any cytotoxicity in the range of 0.1-1.0mg/mL. The results indicated that ß-gal loaded ß-CS NPs could serve as non-toxic delivery carriers for the treatment of lactose intolerance.

Structural Evolution and Toughening Mechanism of ß-Transcrystallinity of Polypropylene Induced by the Two-Dimensional Layered Interface during Uniaxial Stretching.

The structure and morphology of ß-crystals of isotactic polypropylene (iPP) are of great significance because ß-crystals can improve the toughness and ductility of iPP. Toughening of ß-spherulites, which was ascribed to phase transformation, has been extensively investigated. However, the toughening mechanism of other ß-crystals with special structures and morphologies is not clear. In this study, ß-transcrystallinity (ß-TC), which showed a greater toughening effect than that of ß-spherulite, was constructed through microlayered coextrusion. During uniaxial stretching, ß-TC preferred to transform into an α-crystal, whereas ß-spherulite preferred to transform to a smectic mesophase. The transformation degree of ß-TC was much higher than that of ß-spherulite. More importantly, the lamellar fragments from ß-TC gradually rearranged along the stretching direction, accompanied by continuous absorption of energy. The special ß-α phase transformation, high transformation rate, and rearrangement of lamellar fragments led to the highly improved toughness of the layered samples.

Effect of Monascus sp. as an adjunct starter on physicochemical properties and proteolysis in semi-hard cheeses during ripening.

Two kinds of semi-hard cheeses, with Monascus purpureus and without M. purpureus, were manufactured, and effects of M. purpureus on physicochemical properties and proteolysis were evaluated during 36 days of ripening. Addition of M. purpureus changed the microbial survival and showed no significant effect on physicochemical properties of the cheeses, including dry matter and pH. Regardless on the rind or in the core, the indices of proteolysis had no significant difference (p>0.05), whereas there were significant differences of total free amino acid (FAA) and individual FAA between cheeses; this indicated that M. purpureus had no significant effect on the primary proteolysis, but affected the content and ratio of individual FAAs during maturation. Electrophoretic analysis showed strong degradation of αs1-casein in the core and on the rind of cheeses, while ß-casein was highly degraded on the rind but less in the core. Thus, Monascus spp. might have a potential application in the manufacture of cheeses.

Shelf life and storage stability of spray-dried bovine colostrum powders under different storage conditions.

Spray dried bovine colostrum (SDBC) powders were packaged in aluminium-laminated polyethylene (ALPE) and polyethylene terephthalate (PET) pouches and then stored under different conditions (25 °C and 50 % relative humidity (RH), 4 °C and 40-70 % RH, 50 °C and 20-50 % RH). The shelf life of SDBC powder was evaluated as 425.5 and 86.5 days in ALPE and PET pouches under 25 °C and 50 % RH, respectively. The storage stability of SDBC powder in terms of quality parameters including thiobarbituric acid (TBA), hydroxymethyl furfural (HMF), colour change, moisture content and IgG concentration was studied in both packaging materials under different storage conditions. Results showed that ALPE pouches were more suitable for packaging SDBC powder than PET pouches and storage condition of 4 °C and 40-70 % RH was relative suitable for keeping quality of SDBC powder. The glass transition concept was helpful for evaluating the chemical stability of SDBC powder during storage.

Characterization and antimicrobial properties of water chestnut starch-chitosan edible films.

The characterization and antimicrobial properties of water chestnut starch-chitosan (WSC) films containing Cornus officinalis fruit extract (COE 1% w/w), glycerol monolaurate (GML 1% w/w), nisin (10,000 IU/g), pine needle essential oil (PNEO 0.35% v/v), and their combinations were evaluated. Incorporation of COE decreased pH value of the film-forming solution, the moisture content and the water absorption expansion ability (WAEA). GML-incorporated film had lower WAEA, tensile strength, elongation and puncture strength. However, films with nisin displayed good mechanical properties. All the treated films were less transparent and higher in water vapour permeability values. For film microstructure, the presence of PNEO caused discontinuities with lipid droplets or holes embedded in a continuous network and the incorporation of GML led to abaisse-like structures. The COE, GML, nisin, PNEO and their combinations incorporated in the WSC films are effective in inhibiting the growth of Escherichia coli O157:H7, Staphylococcus aureus and Listeria monocytogenes at different levels. The results showed that WSC films containing COE and GML, GML and nisin, COE and nisin were able to reduce the number of E. coli O157:H7, S. aureus and L. monocytogenes. This research has potential applications to the extension of the shelf life of food products.

7-(Hydroxy-meth-yl)-2-(1-hydr-oxy-1-methyl-ethyl)-4-meth-oxy-2,3-dihydro-5H-furo[3,2-g]chromen-5-one methanol hemisolvate.

The title compound (cimifugin), C(16)H(18)O(6)·0.5CH(3)OH, was isolated from the rhizome of Actaea asiatica Hara. The asymmetric unit contains two independent mol-ecules and a solvent methanol mol-ecule. The five-numbered ring adopts an envelope conformation in each molecule. Intra- and inter-molecular O-H⋯O hydrogen bonds stabilize the crystal structure.