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Abstract

In this study, microbiological quality of 93 ready-to-eat food products was determined by enumeration of total aerobic bacteria and members of Enterobacteriaceae. Presence of Staphylococcus aureus and Listeria monocytogenes in the products were also investigated. Aerobic colony counts were between 1.9 × 102–3.4 × 108 CFU g−1 for 84.9% and Enterobacteriaceae counts were between 2 × 102 and 6.7 × 106 CFU g−1 for 43% of the samples. S. aureus was detected in 7.5% of the samples, but L. monocytogenes was not detected in any sample. 72.9% of the Enterobacteriaceae isolates showed resistance to at least one antibiotic tested, and 5 among the S. aureus isolates were found to be resistant to penicillin G and 2 against methicillin. Four S. aureus isolates produced only Staphylococcal enterotoxin A and 1 isolate produced both Staphylococcal enterotoxin A and B. Biofilm experiments revealed biofilm formation on polystyrene for 95.8%, 87.5%, and 91.6% of Enterobacteriaceae isolates at 4 °C, 22 °C, and 37 °C, respectively, whereas all S. aureus isolates formed biofilm at all temperatures.

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Abstract

The objective of this research is to develop a dehusked coconut grading machine for coconut cultivators and entrepreneurs. The basis of design is characterized by a tapered belt conveyor and sizing board with openings of increasing aperture which run along the edge of the belt conveyor. Dehusked coconuts are fed onto the tapered belt conveyor where the gravitational force pushes the nut towards the edge until it comes in contact with sizing board. Due to the tangential force, the nut reels along the sizing board, where dehusked coconuts are graded and allowed to fall through aperture according to their sizes. Performance tests indicated that the inclination angle and velocity of the belt significantly affected contamination ratio, grading efficiency and capacity at 5% significance level. The most efficient configuration for fully husked coconut and semi husked was a belt speed of 1.3 m/s with the inclination angle of 15° and belt speed of 1.5 m/s with the inclination angle of 15° respectively. The machine is acceptable by coconut growers and entrepreneurs.

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Abstract

Effect of coating with calcium nitrate in three concentrations (0.0, 0.5, and 1.0 wt%) on chemical and mechanical properties, and impact behaviour of two apple cultivars (Golden Delicious (GD) and Red Delicious (RD)) during time (0, 2, and 4 months) was studied. Moisture content, pH, titratable acidity, °Brix, organoleptic properties, modulus of elasticity (E), yield stress, yield strain, and toughness were measured. The effect of impact loads was determined by measuring bruise volume (BV) and bruise susceptibility (BS). The results showed that pH and °Brix significantly increased, while titratable acidity, E, yield strain, toughness, and BV decreased during storage time. As Ca(NO3)2 concentration increased, titratable acidity, E, yield strain and yield stress increased and pH decreased (P < 0.05). Highest and lowest values for °Brix were observed in GD treated with 1.0% Ca(NO3)2 after four months (13.31) and GD treated with 0.5% Ca(NO3)2 at the first day (10.65), respectively. Maximum E was obtained in GD treated with 1.0% Ca(NO3)2 on the first day (2130 kPa) and this sample also showed the lowest BS after four months of storage (2.82 mL J−1), while the uncoated GD had the highest BS on the first day (7.11 mL J−1).

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Acta Alimentaria
Authors: B. Csehi, B. Salamon, T. Csurka, E. Szerdahelyi, L. Friedrich, and K. Pásztor-Huszár

Abstract

Bovine blood samples were treated with high hydrostatic pressure (HHP) to examine the changes that may occur in the blood related to its colour, microbiological characteristics, protein denaturation, and dynamic viscosity. Pressure treatments were carried out from 100 to 600 MPa in 100 MPa scale up, with 5 min holding time. The blood samples were treated with anticoagulant (EDTA) to eliminate the possible measurement distorting effects. We found that 2 log reduction in the microbial load could be achieved with a pressure treatment above 400 MPa. According to the protein denaturation measurements (DSC), blood proteins were resistant to pressure treatment, even at 300–400 MPa a substantial part of proteins remained in native state. The colour of the samples got darker with the rising pressure, however, visible colour change was observed only above 400 MPa. It can be established, that the HHP treatment was suitable to increase the microbiological stability of blood, without significantly changing its techno-functional properties.

Open access

Abstract

The main purpose of this study was to determine the chemical composition of monofloral bee-collected pollen from the coffee (Coffea robusta) plant and its pellet morphology. According to the results coffee bee pollen (CBP) has a high nutritional value. It contains a large percentage of protein, reducing sugar, and lipid. Also, vitamins (B2 and E) and minerals (K, Ca, and P) were found in CBP. In addition, the results revealed that the total polyphenols content (TPC) was 10.62 mg GAE/g dry weight (DW) and antioxidant activity (AA) of CBP was 5.52 μmol TE/g DW. Some physical properties of CBP pellet were recorded such as moisture, relative diameter, sphericity, bulk density, and colour parameters. The pollen pellet exhibits shapes of colour from light to dark yellow. These results pointed out that CBP can be used as a remarkable source of compounds with antioxidant activity and health-protective capacity for humans.

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Acta Alimentaria
Authors: D. Das, S. Tamuly, M. Das Purkayastha, B. Dutta, C. Barman, D.J. Kalita, R. Boro, and S. Agarwal

Abstract

Green tea or its concentrated extract is coveted for its health promoting catechin-like polyphenols, especially epigallocatechin-3-gallate (EGCG). However, its amicable efficacy is now being doubted considering the recent occurrence of several cases of hepato- and nephrotoxicity, after the ingestion of EGCG-fortified (≥85–90%) nutritional supplements. Therefore, the current study was carried out to ascertain the effect of green tea leaves extract (GTE), having low EGCG content (73.8%), on liver and kidney functions of male Wistar rats using various in vivo experiments and in vitro radical scavenging activity. In terms of acute toxicity, GTE was observed to be safe when delivered at a dosage of 2000 mg kg−1 body weight (BW). Oral delivery of GTE for 28 days at a concentration of 200 mg kg−1 BW/day did not trigger sub-acute toxicity to the liver and kidneys, as per serum biochemical analyses and histopathological examination. In contrast, GTE counteracted the effects of carbon tetrachloride (a potent hepato-degenerative compound) on the liver. Furthermore, increase in high-density lipoprotein―cholesterol with concomitant lowering of serum triglycerides and low-density lipoprotein―cholesterol were noticed in GTE-treated rats. These findings suggest that low EGCG containing GTE, with appreciable antioxidant activity (IC50 = 53.18–71.28 μg mL−1), can serve as a hepatoprotective, hypolipidemic, and hypocholesterolemic ingredient.

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Abstract

Cake is a popular bakery product consumed by almost everyone due to its low economic cost and shelflife, however, it is recognised unhealthy because of high fat and sugar contents. The aim of this study was to evaluate physicochemical and sensory properties of muffins baked using 100% of sugar and fat replacement as stevia sweetener (rebaudioside A and erythritol) and chia seed mucilage, respectively. The combination of sweetener with chia gel (SCC) had the highest moisture content, while the replacement of fat in muffin (CC) revealed similarity to the control in lightness and redness values. There was also no significant difference in terms of firmness when only the sweetener was replaced (SC). While the control muffin obtained the highest overall acceptability score, the lowest score was observed in CC. Thus, muffins with reduced fat and sugar contents can benefit the consumer in terms of health, but further optimisation of formulations for both replacers is needed for better sensory acceptance.

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Abstract

Seventeen samples of Calabrian ewe’s milk, ewe’s cheese (Pecorino del Poro) made with raw milk, goat’s milk, and goat’s cheese (Caprino d’Aspromonte) made with raw milk were used to obtain 124 yeast isolates. The most abundant species was Debaryomyces hansenii (61.3%), followed by Candida zeylanoides (32.3%) and Kluyveromyces marxianus (3.2%). The enzymatic profile of 25 selected yeast strains was determined. Lastly, they were studied for their interaction with eight dairy lactic acid bacteria – four coccal-shaped and four rod-shaped. The best strains may be used as adjunct cultures for cheese making.

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Acta Alimentaria
Authors: H. Soltanmoradi, M.S. Maniati, A. Davoodabadi, A. Mosapour, S. Samavarchi Tehrani, M. Pazhoohan, F. Daemi, and H. Khaleghzadeh-Ahangar

Abstract

Depression is a common psychiatric disorder that can be continuous or recurrent. It has been previously reported that intestine probiotics play an essential role in the bidirectional communication of the intestine and brain. This study aims to investigate the antidepressant effects of kefir, a probiotic supplement, and Lactobacillus rhamnosus GG and their potentials in depression-like behaviour treatment in two-week and four-week treatments. In the present study, BALB/c mice were used for this purpose. The saline- and fluoxetine-treated groups were designed as negative and positive control groups, respectively. The forced swimming and tail suspension tests have been performed to assess the level of depression-like activity. We have observed that two-week treatment reduces the duration of depression-like activities, and four-week treatment enhances the antidepressant properties. Overall, our results suggest that kefir, L. rhamnosus GG, and the investigated probiotic supplement have antidepressant-like properties.

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Abstract

Cyclodextrins are widely used in various fields including food industry. In this review, their role in high carbohydrate-containing, starchy foods are reviewed and discussed. Both the effects as functional ingredients affecting the structural properties of starch and as active ingredients slowing down starch digestion and, as a consequence, decreasing the glycaemic index of starchy foods are overviewed without considering the traditional applications as carriers and stabilisers of aroma and flavour, essential oils, polyunsaturated fatty acids, and other bioactive components to enrich foods, even if they are carbohydrate foods. The effect on starch metabolism is explained by the structural transformations caused by cyclodextrins on starch amylose and amylopectin. Several examples are shown how the technological and sensorial properties of bread, rice products, pasta, and other starchy foods are modified by cyclodextrin supplementation, and how the digestibility is changed resulting in reduced glycaemic and insulinaemic effects.

Open access