Comparison of different methods to quantify fat classes in bakery products

Effects of Different Dietary Crude Protein Levels on Reproductive Performance, Egg Quality and Serum Biochemical Indices of Wanxi White Geese in the Laying Period

Crude protein (CP) in diets is essential for maintaining animal health and production performance. However, the protein requirements of Wanxi white geese during the laying period are not well understood. In this study, 120 one-year-old Wanxi white geese were selected and divided into three groups based on similar body weights, namely 14% CP, 15% CP, and 16% CP, with each group consisting of 40 animals. The feed was administered for 120 days. Compared with the 14% CP group, the 15% CP group showed a significant increase in the number of courtships and matings, a reduction in nesting frequency, an enhancement in the egg fertility, and an improvement in the nutritional components, and specific gravity of eggs. Additionally, the 16% CP group promoted the secretion of serum E2, LH, P4, and GnRH while inhibiting the secretion of LEP, compared with the 14% CP group. Taken together, it can be seen that a diet containing 15% CP can enhance the reproductive performance, egg fertility, and egg quality of Wanxi white geese. This study is the first to analyze the effects of different dietary CP levels on the reproductive performance and egg specific gravity of Wanxi white geese during the laying period, providing a theoretical basis for formulating feeding standards for this breed.

Comparative physiological, biochemical and transcriptomic analyses to reveal potential regulatory mechanisms in response to starvation stress in Cipangopaludina chinensis

Cipangopaludina chinensis, as a financially significant species in China, represents a gastropod in nature which frequently encounters starvation stress owing to its limited prey options. However, the underlying response mechanisms to combat starvation have not been investigated in depth. We collected C. chinensis under several times of starvation stress (0, 7, 30, and 60 days) for nutrient, biochemical characteristics and transcriptome analyses. The results showed that prolonged starvation stress (> 30 days) caused obvious fluctuations in the nutrient composition of snails, with dramatic reductions in body weight, survival and digestive enzyme activity (amylase, protease, and lipase), and markedly enhanced the antioxidant enzyme activities of the snails. Comparative transcriptome analyses revealed 3538 differentially expressed genes (DEGs), which were significantly associated with specific starvation stress-responsive pathways, including oxidative phosphorylation and alanine, aspartate, and glutamate metabolism. Then, we identified 40 candidate genes (e.g., HACD2, Cp1, CYP1A2, and GPX1) response to starvation stress through STEM and WGCNA analyses. RT-qPCR verified the accuracy and reliability of the high-throughput sequencing results. This study provides insights into snail overwintering survival and the potential regulatory mechanisms of snail adaptation to starvation stress.

Characterization of a Fermented Beverage from Discarded Bread Flour Using Two Commercial Probiotics Starters

The aim of this study was to develop a plant-based fermented beverage from discarded bread flour and to analyze its characteristics as a novel functional product. Eight cereal-based probiotic beverages were produced by inoculating discarded bread flour with a monoculture of Lactobacillus rhamnosus or a co-culture consisting of lactic acid bacteria and Bifidobacterium. Two additional factors, namely, the addition of amylolytic enzymes and matrix desalting, were studied alongside the type of culture. The organic acid content and microbial growth were monitored during fermentation and storage (15 and 21 days). Proximal composition, gamma-aminobutyric acid, and volatile compounds were measured in the final product. Sensory analysis was only conducted on the enzymatically treated samples. The estimated shelf life of the bread beverage was 15 days. The variables studied significantly influenced the amountof organic acids and specific volatile compounds responsible for the aroma of fermented beverages. The beverage produced via co-culturing was preferred by consumers in the sensory test.

Investigation of the effect of chemical composition of surimi and gelling temperature on the odor characteristics of surimi products based on gas chromatography-mass spectrometry/olfactometry

This study investigated the effects of chemical composition of surimi (prepared by 0, 1, or 2 times of rinsing) and gelling temperature (90 °C and 100 °C) on the odor characteristics of surimi products and the relationship between the chemical composition of surimi and the aroma of surimi products. The once- and twice-rinsed surimi showed a decrease (p < 0.05) of 71.32%, 74.60%, 42.79% and 61.12% in the contents of total amino acids and total fatty acids, respectively. The surimi products prepared with un-rinsed surimi at 90 °C had the highest fish-fragrance score, while those prepared with once-rinsed surimi at 100 °C showed the strongest warmed-over flavor (WOF) and the lowest fish-fragrance score.Gly, Phe, and most of the saturated fatty acids were associated with WOF formation in surimi products, while Leu, Ile, Val, Asp, and unsaturated fatty acids were positively related to their fish-fragrance note.

Effect of the Addition of Soybean Residue (Okara) on the Physicochemical, Tribological, Instrumental, and Sensory Texture Properties of Extruded Snacks

An extrusion process was used to improve the physical and textural characteristics of an extruded snack supplemented with soybean residue (okara). An extreme vertices mixture design with a constraint for okara flour (0−50%), mung bean flour (20−70%), and rice flour (20−80%) resulted in the production of eleven formulations. The color, radial expansion index (REI), bulk density, tribological behavior, and instrumental and sensory texture of the extruded snacks were evaluated. Increasing the quantity of okara resulted in an extrudate with a darker, redder color, decreased REI, increased bulk density, and decreased crispness. The tribological pattern of the snack was determined by its dominant composition (protein, starch, or fiber) in the flour mixture, which contributed to the stability of the lubricating film under rotational shear. A principal component analysis of sensory data captured a total of 81.9% variations in the first two dimensions. Texture appeal was inversely related to tooth packing (r = −0.646, p < 0.05). The optimized formulation for texture preference had an okara content of 19%, which was 104% crispier and 168% tougher than an okara content of 40%. This by-product of soybean milk processing can thus be used to develop gluten-free snacks with desirable physical characteristics and texture.

Quality Improvement of Zhayu, a Fermented Fish Product in China: Effects of Inoculated Fermentation with Three Kinds of Lactic Acid Bacteria

To investigate the effects of inoculation fermentation on the quality of Zhayu (a traditional fermented fish product in China), different amounts of L. plantarum, P. acidilactici, and P. pentosaceus were inoculated into samples, and the safety, nutritional, textural, and flavor properties of the samples were evaluated. Fermentation with lactic acid bacteria (LAB) decreased pH values and total volatile basic nitrogen content. The addition of 10⁸~10⁹ cfu/100 g LAB significantly increased the content of crude fat and water-soluble proteins in Zhayu. The addition of L. plantarum and P. acidilactici increased the content of soluble solids in Zhayu. Moreover, fermentation with LAB made the products tender and softer, and the samples prepared with 10⁹ cfu/100 g LAB presented better overall qualities. Additionally, Zhayu fermented with L. plantarum and P. acidilactici showed the strongest sourness, while the samples prepared with P. pentosaceus showed the strongest umami taste, consistent with the highest contents of Asp (25.1 mg/100 g) and Glu (67.8 mg/100 g). The addition of LAB decreased the relative contents of aliphatic aldehydes, (Z)-3-hexen-1-ol, and 1-octen-3-ol, reducing the earthy and fishy notes. However, LAB enhanced the contents of terpenoids, acids, esters, and S-containing compounds, increasing the sour, pleasant, and unique odors of Zhayu.

Sweetpotato chip texture and fat content: Effects of enzymatic modification of cell wall polymers

Impacts of cell wall polymers on sweetpotato chip texture and fat content were investigated through enzymatic modification. Covington sweetpotato slices were treated with cellulase, hemicellulase, pectinase, pectin methyl esterase, protease, the enzyme blend Viscozyme, or no enzymes (control) at 40-45°C for 0.5-2 h. Treated slices were blanched, dried, and fried in triplicate per experimental condition. Breaking forces of 20 chips per frying replicate were measured followed by chip fat, moisture, sugar, alcohol insoluble solids, glass transition temperature, and color analyses. Untreated slices from each batch (daily check) were fried and analyzed to account for starting material variability. Viscozyme and protease-treated chips had the greatest reduction in breaking force from untreated chips (-30.9% and -23.7%, respectively), while pectin methyl esterase-treated chips had the lowest reduction in breaking force (-9.0%). Chips treated with Viscozyme for 2 h were 6.7-6.3 percentiles lower in fat than the control. Principal component analysis elucidated that chip breaking force was associated with unfried slice puncture force, alcohol insoluble solids, and chip color, and chip fat content was inversely associated with maltose content and glass transition temperature. Breaking down multiple cell wall polysaccharides or structural proteins weakened chip textures, while strengthening the pectic fraction resulted in harder chips. Chip fat reduction also occurred when multiple cell wall polysaccharides were broken down. Therefore, cell wall polymers impact sweetpotato chip texture and fat contents, and their attributes should be considered when selecting cultivars and processes for sweetpotato chips. PRACTICAL APPLICATION: Sweetpotato chips are an increasingly popular snack, but there is little understanding how cell wall polymers impact chip textures and fat contents. Raw sweetpotato slices were enzymatically treated to selectively modify cell wall polymers before frying. Chip breaking forces were lowered by protease or Viscozyme (cell wall enzyme blend) treatments, while breaking forces were increased with pectin methyl esterase. In addition, chip fat contents were reduced by the Viscozyme treatment. Since cell wall modifications could impact chip texture and fat content, cell wall polymer attributes should be considered in selection and processing of sweetpotatoes for chip manufacturing.

Diverse Aquatic Animal Matrices Play a Key Role in Survival and Potential Virulence of Non-O1/O139 Vibrio cholerae Isolates

Vibrio cholerae can cause pandemic cholera in humans. The waterborne bacterium is frequently isolated from aquatic products worldwide. However, current literature on the impact of aquatic product matrices on the survival and pathogenicity of cholerae is rare. In this study, the growth of eleven non-O1/0O139 V. cholerae isolates recovered from eight species of commonly consumed fish and shellfish was for the first time determined in the eight aquatic animal matrices, most of which highly increased the bacterial biomass when compared with routine trypsin soybean broth (TSB) medium. Secretomes of the V. cholerae isolates (draft genome size: 3,852,021–4,144,013 bp) were determined using two-dimensional gel electrophoresis (2DE-GE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) techniques. Comparative secretomic analyses revealed 74 differential extracellular proteins, including several virulence- and resistance-associated proteins secreted by the V. cholerae isolates when grown in the eight matrices. Meanwhile, a total of 8,119 intracellular proteins were identified, including 83 virulence- and 8 resistance-associated proteins, of which 61 virulence-associated proteins were absent from proteomes of these isolates when grown in the TSB medium. Additionally, comparative genomic and proteomic analyses also revealed several strain-specific proteins with unknown functions in the V. cholerae isolates. Taken, the results in this study demonstrate that distinct secretomes and proteomes induced by the aquatic animal matrices facilitate V. cholerae resistance in the edible aquatic animals and enhance the pathogenicity of the leading waterborne pathogen worldwide.

Effect of Psyllium on Physical Properties, Composition and Acceptability of Whole Grain Breads

Despite the clear nutritional advantages of wholemeal breads, their consumption is lower than recommended, mainly due to their lower organoleptic quality. This paper proposes the use of psyllium to improve the quality of these breads. For this aim, a wholemeal bread control is compared to breads with psyllium added in different amounts (1 to 10%). Mixolab was used to analyse dough behaviour. Specific volume, texture, macronutrient composition, and bread acceptability were also analysed. Increasing amounts of psyllium resulted in an increased dough hydration and stability, but a reduced kneading time. Specific volume and weight loss were not affected, despite the higher hydration level of the doughs. The addition of psyllium reduced bread hardness and increased its cohesiveness and resilience, thus lowering staling. The addition of psyllium also reduced the calorie content of the breads, due to increased moisture and fibre content. Moreover, the addition of up to 5% psyllium clearly improves the acceptability of wholemeal breads. The use of psyllium can improve the organoleptic and nutritional quality of wholemeal breads, improving their acceptability by consumers.

Particulate matters, aldehydes, and polycyclic aromatic hydrocarbons produced from deep-frying emissions: comparisons of three cooking oils with distinct fatty acid profiles

It is recognized that hazardous emissions produced from frying oils may be related to oil properties, particularly the fatty acid composition. However, investigations have been limited and partial. In this work, the emissions from deep-frying foods with three oils (palm, olive, and soybean oils) with distinct fatty acid profiles were comprehensively examined in a simulated kitchen, and the interrelationship among emitted substances, oil quality parameters, and fatty acids profiles was explored. Firstly, palm oil emitted the highest number concentration of total particle matters ((3895 ± 1796) × 103 #/cm3), mainly in the Aitken mode (20-100 nm). We observed a positive correlation between particle number concentration and levels of palmitic acid, a major saturated fatty acid (SAFA) (rs = 0.73, p < 0.05), and total polar compounds (TPC) (rs = 0.68, p < 0.05) in the fried oil, a degradation marker which was also positively correlated with that of black carbon (BC) (rs = 0.68, p < 0.05). Secondly, soybean oil emitted the highest level of gaseous aldehydes (3636 ± 607 μg/m3), including acrolein, propinoaldehyde, crotonaldehyde, hexanal, and trans-2-heptenal; the total aldehyde concentration were positively correlated with α-linolenic acid (ALA) percentage (rs = 0.78, p < 0.01), while hexanal and trans-2-heptenal were with linoleic acid (LA) (rs = 0.73 and 0.67, p < 0.05). LA and ALA were two major polyunsaturated fatty acids in non-tropical plant oils. Thirdly, palm oil emitted the most particle-bound polycyclic aromatic hydrocarbons (PAHs), and a positive association was discovered between two PAHs and SAFA percentage. Olive oil seems superior to soybean and palm oils with regards to toxic emissions during deep-frying.

Energy Density and Nutrient Contents of Selective Chinese New Year Snacks

BACKGROUND

In this study, the energy density and nutrient contents of thirty Chinese New Year (CNY) snacks commonly consumed in the Asian region during the CNY festive season were measured.

METHODS

Calorie Answer™, Gas Chromatography-Mass Spectrometry (GC-MS) and Inductively coupled plasma-mass spectrometry (ICP-MS) were the main methods applied in this study.

RESULTS

All snacks showed high energy density (kJ/100 g) and the nutrient content, including macro-and micronutrients of these snacks were remarkably different. The most abundant minerals in these snacks include sodium, magnesium, potassium, and calcium. Palmitic (C16:0), oleic (C18:1) and linoleic (C18:2) acids were the main fatty acids and trans-fat was only identified in Butter cookies.

CONCLUSIONS

This study provides a large database on macro- and micronutrient contents in CNY snacks consumed in the Asian region that has not been previously reported. Our results indicate that the snacks were generally energy-dense and nutrient-poor. This study provides necessary information to enable the reformulation of snacks with lower saturated fat and sodium content. It is also a source of information for consumers to select healthier snacks.

Comparative Proteomics and Secretomics Revealed Virulence and Antibiotic Resistance-Associated Factors in Vibrio parahaemolyticus Recovered From Commonly Consumed Aquatic Products

Vibrio parahaemolyticus is a seafoodborne pathogen that can cause severe gastroenteritis and septicemia diseases in humans and even death. The emergence of multidrug-resistant V. parahaemolyticus leads to difficulties and rising costs of medical treatment. The bacterium of environmental origins containing no major virulence genes (tdh and trh) has been reported to be associated with infectious diarrhea disease as well. Identification of risk factors in V. parahaemolyticus is imperative for assuming food safety. In this study, we obtained secretomic and proteomic profiles of V. parahaemolyticus isolated from 12 species of commonly consumed aquatic products and identified candidate protein spots by using two-dimensional gel electrophoresis and liquid chromatography tandem mass spectrometry techniques. A total of 11 common and 28 differential extracellular proteins were found from distinct secretomic profiles, including eight virulence-associated proteins: outer membrane channel TolC, maltoporin, elongation factor Tu, enolase, transaldolase, flagellin C, polar flagellin B/D, and superoxide dismutase, as well as five antimicrobial and/or heavy metal resistance-associated ABC transporter proteins. Comparison of proteomic profiles derived from the 12 V. parahaemolyticus isolates also revealed five intracellular virulence-related proteins, including aldehyde-alcohol dehydrogenase, outer membrane protein A, alkyl hydroperoxide reductase C, phosphoenolpyruvate-protein phosphotransferase, and phosphoglycerate kinase. Additionally, our data indicated that aquatic product matrices significantly altered proteomic profiles of the V. parahaemolyticus isolates with a number of differentially expressed proteins identified. The results in this study meet the increasing need for novel diagnosis candidates of the leading seafoodborne pathogen worldwide.

Effects of a daily three-meal pattern with different dietary protein contents on pig growth performance, carcass and muscle quality traits

BACKGROUND

Recent research related to phase-feeding programmes for pig nutrition do not always account for the variation among individuals, and feeds are usually formulated to optimise the performance of the whole pig population. This study aimed at measuring the effects of a daily three-meal pattern with different dietary protein contents on pig growth performance, carcass and muscle quality traits.

RESULTS

The results showed that compared with the 3C treatment, average daily gain (ADG) of pigs in the HCL treatment increased by 14.75% (P < 0.05) during period 1. The carcass weight (P = 0.006) and slaughter weight (P = 0.021) in the HCL group increased when compared with those in the 3C and LCH treatments. Moreover, the LCH feeding sequences contributed to reduce the drip loss in longissimus dorsi (LD) muscle (P < 0.05) when compared with the 3C treatment. The HCL or LCH feeding sequence contributed to increase the meat quality when compared with those receiving the 3C treatment.

CONCLUSION

Collectively, our results indicate that feeding high protein meal in the morning and a gradual reduction of the protein content in meals over the day may improve muscle quality characteristics, maximise performance, and reduce the pig feed cost. © 2017 Society of Chemical Industry.

Development and validation of methodologies for the quantification of phytosterols and phytosterol oxidation products in cooked and baked food products

Chromatography-mass spectrometry (GC-MS) methodologies for the analysis of the main phytosterols (PS) and phytosterol oxidation products (POPs) present in 19 different foodstuffs cooked or baked using margarines with or without added plant sterols are presented. Various methods for fat extraction were evaluated to allow the GC-MS analysis of large numbers of prepared vegetable, fish and meat products, egg and bakery items in a practically feasible manner. The optimized methods resulted in a good sensitivity and allowed the analysis of both PS and POPs in the broad selection of foods at a wide range of concentrations. Calibration curves for both PS and POPs showed correlation coefficients (R(2)) better than 0.99. Detection limits were below 0.24mgkg(-1) for PS and 0.02mgkg(-1) for POPs, respectively. Average recovery data were between 81% and 105.1% for PS and between 65.5 and 121.8% for POPs. Good results were obtained for within- and between-day repeatability, with most values being below 10%. Entire sample servings were analyzed, avoiding problems with inhomogeneity and making the method an exact representation of the typical use of the food by the consumer.

Comparison of two derivatization methods for the analysis of fatty acids and trans fatty acids in bakery products using gas chromatography

Two different procedures for the methylation of fatty acids (FAs) and trans fatty acids (TFAs) in food fats were compared using gas chromatography (GC-FID). The base-catalyzed followed by an acid-catalyzed method (KOCH3/HCl) and the base-catalyzed followed by (trimethylsilyl)diazomethane (TMS-DM) method were used to prepare FA methyl esters (FAMEs) from lipids extracted from food products. In general, both methods were suitable for the determination of cis/trans FAs. The correlation coefficients (r) between the methods were relatively small (ranging from 0.86 to 0.99) and had a high level of agreement for the most abundant FAs. The significant differences (P = 0.05) can be observed for unsaturated FAs (UFAs), specifically for TFAs. The results from the KOCH3/HCl method showed the lowest recovery values (%R) and higher variation (from 84% to 112%), especially for UFAs. The TMS-DM method had higher R values, less variation (from 90% to 106%), and more balance between variation and %RSD values in intraday and interday measurements (less than 4% and 6%, resp.) than the KOCH3/HCl method, except for C12:0, C14:0, and C18:0. Nevertheless, the KOCH3/HCl method required shorter time and was less expensive than the TMS-DM method which is more convenient for an accurate and thorough analysis of rich cis/trans UFA samples.