Traditional Greek yogurt-based salad Tzatziki is one of the most popular ready-to-eat deli salads in Greece. The objective of this study was to estimate the microbial stability of Tzatziki, with and without chemical preservatives, using a rapid method. Determination of the microbial count was carried out using the bioluminescence method (ATP) and traditional microbiological analysis, plate-counting method (CFU) in various batches of the final product of Tzatziki. The results showed that the Tzatziki salad without preservatives initially gave higher relative light units (RLU) values (79,532) than the same salad with preservatives (43,198) because the potassium sorbate and the sodium benzoate, used the in recipe, appeared to suspend the action of microorganisms. After incubation in two different substrates, MacConkey and Sabouraud, the Tzatziki salad without preservatives gave higher RLU values (9,488 and 16,176, respectively) than the salad with preservatives (12,780 and 12,005, respectively). In the two selective substrates, differences appeared between the two methods of microbial count (RLU and CFU). While RLU values were roughly at the same level, the CFU values presented significant differences (p < 0.05). It was also shown that there was a strong correlation (R 2 = 0.93-0.95) between bacterial counts estimated by traditional CFU and ATP methods. As expected, the dominant microbial population in Tzatziki was Lactobacillus spp., originated from yogurt. Coliforms and yeasts were not able to survive in this environment. Generally, according to the results, Greek traditional Tzatziki salad was a microbial stable product and the bioluminescence method could be a rapid method to determine its microbial state. 

The present investigation was designed to characterize the phenolic profile of Lima beans (Phaseolus Lunatus) and also to evaluate the antioxidant indices: total phenolic content (TPC), total flavonoid content (TFC), ferric reducing antioxidant power (FRAP), 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and amino acid composition at different stages of simulated gastrointestinal digestion (oral, gastric, intestinal). High Performance Liquid Chromatography (HPLC-DAD) analysis revealed the presence of some phenolic compounds (gallic acid, catechin, caffeic acid, rutin, quercitrin, quercetin, kaempferol and apigenin), with a reduced amount (mg/g) after cooking: gallic acid (raw: 1.96 ± 0.02; cooked: 1.82 ± 0.01); catechin (raw: 0.83 ± 0.01; cooked: 0.73 ± 0.01); rutin (raw: 2.61 ± 0.03; cooked:1.74 ± 0.03); quercitrin (raw: 5.73 ± 0.01; cooked: 5.68 ± 0.01); apigenin (raw: 2.09 ± 0.01; cooked: 1.79 ± 0.02), with exception of quercetin (raw: 2.11 ± 0.02; cooked: 5.73 ± 0.02) and caffeic acid (raw: 2.08±0.04; cooked 2.95 ± 0.04). The results of the antioxidant indices of in vitro enzyme digested lima beans revealed higher values for cooked Lima beans compared to the raw counterpart, with a stepwise increase at the different stages of in vitro digestion, with the exception of ferric reducing antioxidant power; TPC (oral digestion: 65.44 ± 0.96; gastric digestion:134.87 ± 0.46; intestinal digestion: 517.72 ± 4.70; mg/g tannic acid equivalent), TFC (oral digestion: 199.30 ± 6.43; gastric digestion: 1065.97± 1.22; intestinal digestion: 3691.87 ± 4.2; mg/g quercetin equivalent), DPPH (oral digestion: 85800.00 ± 305.50; gastric digestion: 99066.66 ± 115.47; intestinal digestion: 211354.20 ± 360.84; µmol TE/g sample). The results also revealed a progressive increase in the antioxidant indices and amino acid composition (mg/kg) for both raw and processed lima beans at various stages of the in vitro digestion, with the intestinal phase of simulated digestion ranking higher. This implied that the Lima beans contained some essential amino acids and antioxidant molecules that would be readily available after passing through the gastrointestinal tract and could therefore be explored as functional food in the management of free radical mediated diseases.

In this study, seventeen (17) composite blends of broken rice fractions and full-fat soybean, formulated using response surface methodology and central composite design within a range of barrel temperatures (100-140oC), initial feed moisture content (15-25%) and soybean composition (8-24%), were extruded with a twin-screw extruder and the expansion and color indices were optimized. The results indicated a significant (p<0.05) effect of extrusion conditions on the responses. Fitted predictive models had coefficients of 88.9%, 95.7%, 97.3%, 95.4% and 95.2%, respectively, for expansion index, bulk density, lightness, redness and yellowness. The p-value and lack-of-fit tests of the models could well explain the observed variability and therefore could be used to establish production setting for the twin-screw extruder. The optimum extrusion conditions were found to be 130 oC (barrel temperature), 20% (feed moisture level) and 23% feed soybean composition and optimum responses in terms of bulk density, expansion index, lightness, redness and yellowness chroma indices were 0.21 g cm−3 , 128.9%, 17.1, 3.13 and 24.5, respectively. This indicates that optimum conditions can be established in twinscrew extrusion cooking of broken rice fractions and full-fat soybean composite blends that can result in product of low bulk and maximum expansion with a satisfactory light yellow product color that can be used to produce products that valorize broken rice and reduce qualitative postharvest loss.

Green tea Camellia sinensis contains polyphenol that has antidiabetic activity. Mangrove leaves also contain polyphenol which potentially gives these leave antidiabetic activity. The aim of this research was to determine the ability of herbal green tea extract from white mangrove (Avicennia marina) leaves to decrease blood glucose level of diabetic Wistar rats (Rattus novergicus). The method used was experimental and involved giving a herbal green tea extract from white mangrove leaves with concentration of 100, 200 and 300 mg/200g BW/day, and positive control, i.e. glybenclamide (0.09 mg/200 g BW/day), to diabetic rats injected with Streptozotocin (STZ) and Nicotinamide (NA). The rats were observed on day 0, 5, 10 and 15. The results showed that the herbal green tea extract from white mangrove leaves decreased the blood glucose level of diabetic rats. The effective extract dose that decreased the blood glucose level of diabetic rats was 300 mg/200 g BW, which is comparable to the effect produced by glybenclamide (antidiabetic medicine). This dose could decrease the blood glucose level of diabetic rats to reach a normal blood glucose level after 20 days.

African nutmeg, a possible local substitute for a commercial food flavourant, remains largely underutilized in Nigeria. Its application potential in cookie production was investigated in this study. African nutmeg (Monodora myristica) seed flour (ANM) was produced using a standard method. The flour was substituted for vanilla flavour (VFL) in ratio of 0, 1, 2, 3, and 3.5 g and functional properties of the flour blends (water absorption capacity (WAC), oil absorption capacity (OAC), and bulk density) were determined, using standard methods. Cookies were developed and characterized chemically, physically (colour) and organoleptically using the AOAC method, a colourimeter and sensory panellists respectively. Data were analysed using ANOVA at p<0.05. Replacement of vanilla with African nutmeg had no significant effect on bulk density (0.62 g cm−3 -0.68 g cm−3 ), but significantly affected WAC (133-142 %) and OAC (147-156 %) of flour blends. Crude protein (9.44-15.49 %), crude fat (3.17-6.50 %), total ash (2-2.73 %) and crude fibre (0.12-0.23 %) contents of the cookie increased, whilst metabolizable energy (385.33-367 kcal) decreased. There were reductions in pH (6.83-6.53) and TSS (5.80-1.20). Brown index of the snack increased with addition of nutmeg. Antioxidant indicators (flavonoids, DPPH and phenol) varied among cookie samples. Antinutrients, saponin, tannin and oxalate, were within tolerable limits. All cookie samples were judged acceptable by the panellists, with SLZ being the most acceptable. An acceptable and nutritious snack was produced at 100 % replacement. M. myristica seed could serve as substitute for vanilla in the production of cookies and other related snacks.

Drying conditions of black tea using superheated steam (SHS) were optimized based on a central composite design (CCD) of response surface methodology (RSM). The effects of independent variables (temperature and time) towards the total phenolic content (TPC), scavenging free radical ability, ferric-reducing antioxidant power assay and sensory attributes (infusion colour, aroma, flavour and astringency) were analysed using regression polynomial equations. Analysis of variance (ANOVA) showed that a quadratic model fitted the experimental design well, with a p-value less than 0.05 and a highest coefficient of 0.9474. The optimum drying conditions were achieved at 166.7oC and 21.2 minutes where the experimental values were in accordance with predicted values, with percentage errors (PE) less than 10%. Temperature (140oC – 180oC) was concluded to have the most significant effect and showed a positive direction in most responses. This effect was definitely able to support the application of a SHS dryer for the quality production (antioxidant and sensory properties) of black tea.

In this study, the retention of vitamin C in fresh broccoli stored at different temperatures (i.e. chiller, room, cooking, and roasting or baking; 5-120oC) was investigated. The thermal stability of vitamin C in broccoli was analysed at 5, 20, 45, 60, 70, 80, 110, and 120oC. The vitamin C content was measured by the indophenol titration method. Vitamin C was affected negatively at all stored temperatures. The degradation of vitamin C was modelled by first-order reaction kinetics and the reaction rate constants were observed as 9.03Ö10−8 and 5.65Ö10−3 s −1 when stored at 5oC and 120oC, respectively. The activation energy was estimated as 74.2 kJ/mol within the temperature range used in this study. The lowest decay of vitamin C was observed during the chilling condition. The data on retention of vitamin C in broccoli could be used to determine their stability, when stored as raw, and when heated at different temperatures.

In this study, the effect of processing methods on the nutritional quality and functional properties of cashew (Anacardium occidentale Linn) kernels were investigated. The kernels were soaked, autoclaved, roasted or germinated at varying time duration; raw kernel served as control. The samples were analysed for chemical, mineral bioavailability and functional properties. Data was subjected to analysis of variance and means were separated by the Duncan multiple range test. The result of chemical composition analyses revealed that raw cashew kernels contained 3.55±0.08% moisture, 21.3±0.05% protein, 45.0±0.15% fat, 2.53±0.02% fibre, 1.59±0.02% ash, 26.1±0.01% carbohydrate, 521.75 Kcal/g energy, 2210.09±0.02mg/kg calcium, 1712.54±0.03mg/kg magnesium, 60.04±0.01 mg/kg iron and 36.74±0.02mg/kg zinc. Tannin, phytate and oxalate concentrations in the raw cashew kernel were 10.14±0.03 mg/kg, 99.30±0.02mg/kg and 11.03±0.03mg/kg respectively. Increased fat, ash and fibre levels were noted for treated samples compared to raw kernels. Mineral concentrations were increased significantly by various treatments compared to raw kernel; however, germination resulted in the highest increase of mineral content. A reduction trend was observed in phytate, oxalate and tannin concentrations in the treated samples with respect to increased processing time. Consequently, various treatments influenced the bioavailability of mineral elements. Treated samples exhibited significant differences in loose and packed bulk densities, water and oil absorption capacities when compared to raw kernels. Germination shows potential to generate not only much needed nutrients in cashew for human development, but also improved bioavailability of nutrients and functionality compared to other processing methods. This approach can used in Community Nutrition and Emergency Feeding Programmes, in developing countries, where the consequence of anti-nutritional factors may worsen the incidence of malnutrition and disease.

The aim of this work was to study the effect of UV-C radiation on ultrasound assisted extraction (UAE) of cherry tomato bioactive compounds. Cherry tomatoes were exposed to two UV-C radiation doses (0.5 and 1.0 J cm−2 ) and stored at 20 ± 0.5 oC for 7 days. Next, they were lyophilized, and the bioactive compounds were extracted by UAE at 20 KHz. To evaluate the effectiveness of the extraction process of the bioactive compounds, a CCRD (central composite rotational design) was used together with RSM (response surface methodology), for extraction times from 4 to 12 minutes and concentrations (g of lyophilized product / L of ethanol) of 1:10, 1:20 and 1:30. The extracts obtained from the irradiated tomatoes presented 5.8 times more lycopene content than the controls and higher antioxidant activity was obtained for 4 and 8 min, in the concentrations 1:10 and 1:20 (m v −1 ). Through numerical model optimization, optimal extraction conditions were obtained. The results demonstrated that by previously irradiating tomatoes with UV-C light, the UAE yielded considerably higher amounts of lycopene and other bioactives. 

The present work aimed to: i) find the suitable proportion, based on sensory evaluation, of microwave-convective hot air dried jamun (Syzygium cumini L.) pulp and seed kernel powder to be mixed for the preparation of jamun powder (JP); ii) generate and model the moisture sorption isotherm (MSI) of JP; and iii) estimate net isosteric heat of sorption (qst), spreading pressure (Φ), net integral enthalpy (Qin), and net integral entropy (Sin). To formulate JP, the proportion (w/w, db) comprising 2% kernel and 98% pulp powder was the most desirable. The Peleg model was the best fit to MSI of JP. The qst decreased following linear relationship from 11.02 kJ. mol−1 at 5% equilibrium moisture content (EMC) to 0.27 kJ. mol−1 at 30% EMC. The Φ increased with increase in water activity and decreased with increase in temperature from 25 oC to 35 oC, and the values of Φ at 45 oC were even higher than at 25 oC. Net integral enthalpy (Qin) initially decreased till 6% moisture content in JP and displayed an increasing trend with further increase in moisture content. On the contrary, Sin kept on decreasing continually with increasing moisture content. The moisture zone of 7-11% was considered safe for storage of JP within the temperature range of 45-25 oC.