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Vine tea (Ampelopsis grossedentata) is a tea plant cultivated south of the Chinese Yangtze River. It has anti‐inflammatory properties and is used to normalize blood circulation and detoxification. The leaves of vine tea are the most abundant source of flavonoids, such as dihydromyricetin and myricetin. However, as the main bioactive flavonoid in vine tea, dihydromyricetin was the main focus of previous research. This study aimed to explore the antibacterial activities of vine tea against selected foodborne pathogens. The antimicrobial activity of vine tea extract was evaluated by the agar well diffusion method. Cell membrane integrity and bactericidal kinetics, along with physical damage to the cell membrane, were also observed. The extract was analyzed using a high‐performance liquid chromatography‐diode array detector (HPLC‐DAD), and the results were confirmed using a modified version of a previously published method that combined liquid chromatography and electrospray‐ionized quadrupole time‐of‐flight mass spectrometry (LC‐ESI‐QTOF/MS). Cell membrane integrity and bactericidal kinetics were determined by releasing intracellular material in suspension and monitoring it at 260 nm using an ultraviolet (UV) spectrophotometer. A scanning electron microscope (SEM) was used to detect morphological alterations and physical damage to the cell membrane. Six compounds were isolated successfully: (1) myricetin (C15H10O8), (2) myricetin 3‐O‐rhamnoside (C21H20O12), (3) 5,7,8,3,4‐pentahydroxyisoflavone (C15H10O7), (4) dihydroquercetin (C15H12O7), (5) 6,8‐dihydroxykaempferol (C15H10O8), and (6) ellagic acid glucoside (C20H16O13). Among these bioactive compounds, C15H10O7 was found to have vigorous antimicrobial activity against Bacillus cereus (AS11846) and Staphylococcus aureus (CMCCB26003). A dose‐dependent bactericidal kinetics with a higher degree of absorbance at optical density 260 (OD260) was observed when the bacterial suspension was incubated with C15H10O7 for 8 h. Furthermore, a scanning electron microscope study revealed physical damage to the cell membrane. In addition, the action mode of C15H10O7 was on the cell wall of the target microorganism. Together, these results suggest that C15H10O7 has vigorous antimicrobial activity and can be used as a potent antimicrobial agent in the food processing industry.

The physicochemical properties, swelling power, solubility, and digestibility of flour from four rice varieties (black, brown, white, and waxy rice flour) were analyzed. The results showed that the black and brown rice had high‐amylose percentage (21.8% and 20.5%), a relatively low percentage of starch content (68.1% and 79.1%), and lower swelling power (6.6% and 7.6%) and solubility (13.5% and 15.7%), respectively. Waxy rice flour attributed to lower gelatinization temperatures and higher enthalpy values. Meanwhile, the brown, black, and white rice showed higher gelatinization temperature and lower enthalpy value. The black and brown rice flour exhibited lower pasting and viscosity values as compared to waxy rice flour. The results showed that all rice flour had an A‐type X‐ray diffraction pattern, and after cooking all rice flour showed V‐type polymorphs except waxy rice flour. Brown and black rice flour after cooking have lower digestion rate than white rice and waxy rice flour, probably due to its lower expansion and solubility rates, and higher gelatinization temperature., Rosa Roxburghii seed oil was of high quality in terms of its high amount of unsaturated fatty acids. Heat treatment of R. roxburghii seed oil showed an increase in the relative percentage of linoleic acid and linolenic acid isomers with increasing temperature and time. The formation of linoleic acid and linolenic acid isomers followed a zero order reaction.

Pomegranate (Punica granatum) acts as a therapeutic fruit possessing different bioactive compounds. Different compartments of pomegranate (P. granatum) like seed, peel, juice and leaves are rich in potential bioactive compounds. Pomegranate contains sinapyl, coniferyl, ellagic acid, cinnamic acid, genistein, linoleic acid, anthocyanin, gallic acid, catechin, quercetin, rutin, kaempferol, cyanidin, punicalin, delphinidin, punicalagin, chlorogenic acid, coumaric acid, luteolin and pelletierine alkaloids, flavonoids, anthocyanin and caffeic acid. Pomegranate also exhibits significant anti-oxidative, anti-hypertensive, cardioprotective and anti-diabetic properties and anti-carcinogenic possessions including prevention of prostate cancer; reduction in colon inflammation, prevention of skin tumorigenesis, improvement in renal function and reduction in metastatic melanoma growth. This review summarizes the current available data on the phytochemistry, bioavailability and therapeutic importance of potential bioactive compounds of pomegranate.

Oat predominately cultivated as forage crop and is not explored for its value-added bioactive moieties. This study was aimed to characterize five selected oat (Avena sativa L.) cultivars with respect to organic sugars, antioxidant activities, pesticide residues, mycotoxin and phenolic acids as measured HPLC. Five indigenous oat cultivars (Avon, PD2LV65, S2000, SGD2011, SGD81) were profiled for seven phenolic acids (gallic acid, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, chlorogenic acid and ferulic acid). Highest concentrations of vanillic acid, gallic acid, caffeic acid, syringic acid, ferulic acid, p-coumaric acid and chlorogenic acid were detected in the SGD2011, SGD81, S2000, SGD2011, S2000, SGD2011 and PD2LV65 respectively. TPC in case of all oat cultivars ranged 50.88–101.56 mg/100 g. Among all oat cultivars, SGD-81 exhibited the highest DPPH activity, TPC, TFC and TFoC contents whereas, SGD-2011 showed the highest total anthocyanin content followed by AVON. S2000 showed the highest concentration of mycotoxin M1 (18.51 ppm), while lowest M1 content (10.51 ppm) were exhibited by SGD-81. Abamectin and permethrin pesticide residues were undetected in oat cultivars whereas, Dieldrin was only detected in SGD-81 and chloropyrifos was not detected in S2000 and SGD-81. Mandipropamid, parathion methyl, chlorthalonil, indoxacarb and lufernon were detected in the highest concentrations in SGD2011 and S2000 oat cultivars. Moreover, fructose, glucose and sucrose were found in highest amounts in S2000, PD2LV65 and SGD2011, respectively. Conclusively, it was evident from the results that SGD-81, SGD2011 and SG2000 could be utilized as source of important and promising phytochemicals of nutraceutical significance. Moreover, significant potential of these oat cultivars can be harnessed owing to value addition and exploitation in formulations of functional food ingredients and foodstuffs.

Polyphenols are natural antioxidants and play a very vital role in inhibition of oxidative stress as induced by free radicals in the body. Apple and pomegranate peels are significant agro-industria...

Cheddar is a nutritious, hard type of cheese manufactured by milk acidification followed by enzymatic gel formation. It is a dynamic cheese variety that experiences substantial changes during ripening. Freshly made Cheddar curd has bland aroma and taste which is converted to flavored and smooth textured cheese during ripening. The chemical and microbiological changes occurring are grouped into glycolysis, lipolysis and proteolysis followed by secondary reactions like metabolism of amino acids and fatty acids imperative for the production of compounds necessary for cheese flavor. The key feature of Cheddar manufacture is the conversion of lactose to lactate by mesophilic bacterial starters. The rate and extent of acidification influence the initial texture of the curd by controlling the rate of demineralization. The proteolysis is the most complex of the primary events during cheese ripening, especially in Cheddar type cheese.

The purpose of this study was to develop an in-vitro digestion protocol to evaluate the antioxidant potential of the peptides found in processed cheddar cheese using digestion enzymes. We studied first antioxidant and angiotensin converting enzyme (ACE) inhibition and antioxidant activities of processed cheddar cheese with the addition of spices e.g. cumin, clove and black pepper made from buffalo milk and ripened for 9 months. Then we conducted an in vitro digestion of processed cheddar cheese by gastric and duodenal enzymes. Freeze dried water (WSE) and ethanol soluble fractions (ESE) of processed cheddar cheese were also monitored for their ACE inhibition activity and antioxidant activities. In our preliminary experiments, different levels of spices (cumin, clove and black pepper) were tested into cheese matrix and only one level 0.2g/100g (0.2%) on the basis of cheese weight was considered good concerning sensory evaluation. Significant increase in ACE-inhibition (%) of processed Cheddar cheese as well as its WSE and ESE was obtained. Lower IC50 values were found after duodenal phase digestion compared to oral phase digestion.

Zinc deficiency is a growing issue in developing countries. Moreover, it is a well-known fact that the bakery products have very low zinc content and the further loss of zinc occurs during milling of wheat and under baking of end products, which makes it hard to produce nutritional bakery products. For this purpose, zinc sulfate has been incorporated in wheat flour at 0, 32.5, 65, and 97.5 mg/100 g to prepare cookies and determine their physicochemical and nutritional properties as well as stability under controlled storage conditions, i.e. temperature (23-25 °C) and relative humidity (45-55%). The findings exhibited that the cookies-percentage of fat and protein decreased after the addition of zinc sulfate. The fiber content of cookies was non-significantly changed, while the moisture content increased. Moreover, the diameter of cookies significantly increased from 45.65 ± 1.46 cm to 45.84 ± 1.34 cm. The thickness and spread factor of cookies were also effects ranged from 1.49 to 1.54 cm and 30.63 ± 2.98 to 29.76 ± 1.64 respectively. The results revealed that zinc sulfate was stable up to 90 days and under normal baking conditions. Based on the sensorial attributes, it was unveiled that the nutritional cookies were prepared by using 65 mg zinc sulfate with (AARI-2011) wheat flour.

Ultrasound-assisted extraction (UAE) was used to extract carotenoids from the carrot pomace. To investigate the effect of independent variables on the UAE, the response surface methodology (RSM) with central-composite design (CCD) was employed. The study was conducted with three independent variables including extraction time (min), temperature (°C), and ethanol concentration (%). The results showed that the optimal conditions for UAE were achieved with an extraction time of 17 min, temperature of 32 °C, and ethanol concentration of 51% of total carotenoids (31.82 ± 0.55), extraction time of 16 min, temperature of 29 °C, and ethanol concentration of 59% for a combination of β-carotene (14.89 ± 0.40), lutein (5.77 ± 0.19), and lycopene (2.65 ± 0.12). The non-significant (p &gt, 0.05) correlation under optimal extraction conditions between predicted and experimental values suggested that UAE is the more productive process than conventional techniques for the extraction of carotenoids from the carrot pomace.

The present study was planned to investigate the phytochemical compounds present in Aloe vera and antimicrobial and antioxidant activity of Aloe vera gel powder with different solvents. The phytochemical compounds were screened qualitatively and glycosides, flavonoids, tannins, phenols, saponins, proteins, triterpeniods gave positive results while alkaloids and phlobatannin gave negative results. The polyphenol and flavonoid contents and antioxidant activity of Aloe vera gel powder extract using three different solvents (ethanol, methanol, acetone) were analyzed. The ethanolic extract showed maximum polyphenol (28.44 ± 2.67 mg GAE/g), flavonoid (63.90± 2.39 mg CE/g) and DPPH radical scavenging activity (51.09±0.33%). Antibacterial activity of extracts was examined by agar diffusion method with four microbial species (Salmonella typhi, Escherchia coli, Bacillus subtilis and Staphylococcus aureus). Maximum antibacterial activity was observed in ethanol extract of Aloe vera gel powder. Hence, Aloe vera gel powder can be used as an antimicrobial and antioxidant agent in food preservation and to prevent diseases related to oxidative stress. Keywords: Aloe vera gel powder; Antibacterial activity; Antioxidant capacity; Phytochemicals; Solvents; Total polyphenols http://dx.doi.org/10.19045/bspab.2019.80068

The adverse health effects of dietary sodium demand the production of cheese with reduced salt content. The study was aimed to assess the effect of reducing the level of sodium chloride on the texture, flavor, and sensory qualities of Cheddar cheese. Cheddar cheese was manufactured from buffalo milk standardized at 4% fat level by adding sodium chloride at 2.5, 2.0, 1.5, 1.0, and 0.5% (wt/wt of the curd obtained). Cheese samples were ripened at 6 to 8 °C for 180 d and analyzed for chemical composition after 1 wk; for texture and proteolysis after 1, 60, 120, and 180 d; and for volatile flavor compounds and sensory quality after 180 d of ripening. Decreasing the salt level significantly reduced the salt-in-moisture and pH and increased the moisture-in-nonfat-substances and water activity. Cheese hardness, toughness, and crumbliness decreased but proteolysis increased considerably on reducing the sodium content and during cheese ripening. Lowering the salt levels appreciably enhanced the concentration of volatile compounds associated with flavor but negatively affected the sensory perception. We concluded that salt level in cheese can be successfully reduced to a great extent if proteolysis and development of off-flavors resulted by the growth of starter and nonstarter bacteria can be controlled.

The aim of the study was to evaluate the effect of feed management on conjugated linoleic acid (CLA) level in milk and subsequently on fatty acid profile of cheese. Twenty cows were divided into 2 groups, fed on grass silage and pasture feed with sunflower supplementation for 14 days. Milk samples were collected and analyzed for composition and fatty acid profile using gas chromatograph. Cheddar cheese was manufactured from both milk types and ripened for 120 days. During ripening, it was analyzed for composition and fatty acid quantification. The supplemented diet significantly increased the CLA content in milk. Similarly the cis-9, trans-11 CLA content in Cheddar cheese were more than twofold in case of supplemented diet as compared to grass silage. During ripening, CLA concentration remained stable. The sunflower supplementation showed no effect on cheese composition. Hence, supplemented pasture resulted in elevated CLA content in milk compared to grass silage.

The objective of the study was to compare the sensory profile of Cheddar cheese prepared from cow and buffalo milk using indigenous and commercial cultures. Commercially available and locally isolated, indigenous starter cultures were used to prepare cow and buffalo milk Cheddar cheese. The cheese was ripened at 4 and 12°C and analyzed for descriptive sensory profile by a panel of 10 assessors after 60 and 120 d of ripening. On evaluation, the mean scores for odor, flavor, and texture attributes obtained for buffalo milk cheese were significantly higher than those obtained for cow milk cheese. For most of the traits, cheese samples prepared from indigenous cultures and ripened at higher temperature received higher descriptive scores compared with those of commercial cultures and ripened at lower degrees. Milk sources highly significantly affected the “creamy” and “sour” traits of odor; the “creamy,” “smoky,” and “soapy” flavors; and all the texture attributes except “maturity.” Starter cultures considerably influenced the production of “acidic,” “bitter,” “sweet,” and “sour” characteristics. The use of elevated ripening temperature showed noticeable effect on all the characteristics except the “creamy” odor and flavor. Principal component analysis and hierarchical cluster analysis also showed that milk sources, starter cultures, and ripening temperatures significantly influenced the sensory characteristics.

The effect of sodium chloride on the production of organic acids during ripening of buffalo milk Cheddar cheese at elevated temperature was evaluated. Buffalo milk Cheddar cheese was produced by adding sodium chloride at the rate of 0, 1 and 2% and stored for ripening at 4C and 12C for 120 days. The cheese was evaluated for organic acids i.e., lactic, acetic, citric, pyruvic, formic, butyric and maleic and mineral contents, including sodium, calcium and potassium at 60 and 120 days of ripening. The results showed that elevated ripening temperature accelerated the production of all organic acids and significantly increased their concentrations. However, during ripening, no effect on minerals profile was observed. High level of salt decreased the production of organic acids during ripening irrespective of ripening temperatures. Hence, it was concluded that elevated ripening temperature and enhanced sodium concentrations showed considerable effect on organic acids production. PRACTICAL APPLICATIONS Worldwide, Cheddar cheese is produced from cow's milk, but buffalo milk ranks at the top in Pakistan's milk production and, being nutritionally rich, is more suitable for cheese. Moreover, cheese ripening is a lengthy process and attempts to shorten the ripening time using a range of systems have had varying degrees of success. Organic acids are the major products of glycolysis during ripening and play an integral role in cheese quality. The addition of salt affects the cheese ripening and hence influences the production of organic acids. The project was designed with greater significance to determine the effect of sodium chloride on production of organic acids during accelerated ripening of buffalo milk Cheddar cheese. Practically, the project concluded that the optimal quantity of salt addition should be 1% in cheese manufacturing and recommended the ripening at 12C for 120 days in buffalo milk Cheddar cheese for better compositional profile.

Cheddar cheese was manufactured from cow and buffalo milk using commercially available starter cultures (Lactococcus lactis ssp. Cremoris and Lactococcus lactis ssp. Lactis). Cheese was analyzed for proximate composition, pH, acidity, lactose and mineral contents and sensory perception (flavor, aroma and texture) after 2 and 4 months of ripening. All the chemical composition was significantly influenced by cow and buffalo milk. Buffalo milk cheese was found considerably superior in nutritional profile. Lactose content and pH decreased and acidity increased significantly during ripening of 120 days. On sensory evaluation, buffalo milk cheese was ranked appreciably higher for all the sensory parameters as compared to that of cow milk.

The effect of packaging materials on the physicochemical and rheological characteristics of iron-fortified wholemeal flour (WMF) during storage was determined. WMF was fortified with three fortificants, namely ferrous sulfate (30 ppm), ferrous sulfate + ethylenediamine tetraacetic acid (EDTA) (20 + 20 ppm) and elemental iron (60 ppm). Each flour was also fortified with 1.5 ppm folic acid. Moisture, flour acidity and peroxide value increased during storage, while protein and fat contents decreased. Highest conversion of Fe2+ into Fe3+was observed in flour fortified with ferrous sulfate (2.72%), followed by that fortified with ferrous sulfate + EDTA (1.49%) and elemental iron (1.06%). Water absorption and dough viscosity of iron-fortified flours increased during storage. The flour containing ferrous sulfate was most acceptable regarding sensory characteristics, followed by samples containing ferrous sulfate + EDTA. Fortified flours were more stable during storage than unfortified. Addition of EDTA increased the stability of flours and fortificants. The fortified flours stored in polypropylene bags proved more stable than those stored in the tin boxes. PRACTICAL APPLICATIONS The main role of packaging is to protect the product during handling, distribution and storage against environmental and mechanical hazards. The success of a fortification program depends on the stability of micronutrients and food to which these are added. Chemical changes during storage badly affect chapatti making and sensory properties. Exposure of the fortificant to any factor including heat, moisture, air or light, and acid or alkaline environments during processing, packaging, distribution, or storage affects its stability. Flour containing elemental iron and ferrous sulfate with EDTA remained stable up to 42 days. The unfortified flour and flour containing ferrous sulfate remained stable for 21 days in tin boxes and 28 days in the polypropylene bags. Wheat flour milling industry would be benefited from this research if government is keen to launch iron fortification program in the country to curb iron deficiency anemia among population.

4 Abstract: A study was conducted to determine the effect of citrus peel essential oils on the microbial growth and sensory characteristics of bread. Citrus peel essential oils extracted by cold expression from malta (Citrus sinensis) and mossumbi (Citrus sinensis) were applied in different forms (treatments) separately. The essential oils significantly affected sensory characteristics such as symmetry of form, character of crust , colour of crumb, colour of crust, taste, texture, aroma and grain of bread. They also inhibited and delayed the microbial growth in the bread. Maximum inhibitory effect was achieved against molds and bacteria by spraying the malta peel essential oil on bread.

Bread dough is usually fermented with yeast but in the present study sourdough lactic acid bacteria (Lactobacillus bulgaricus) alone and in combination with yeast (Saccharomyces cerevisiae) were used to determine their effect on the shelf life and sensory characteristics of bread at different intervals of storage. Lactic acid bacteria improved the sensory characteristics of bread such as volume, evenness of bake, character of crust, grain of bread, colour of bread crumb, aroma, taste and texture of bread and extended shelf life of bread by inhibiting the growth of microbes.

Xylitol is a pentahydroxy sugar-alcohol which exists in a very low quantity in fruits and vegetables (plums, strawberries, cauliflower, and pumpkin). On commercial scale, xylitol can be produced by chemical and biotechnological processes. Chemical production is costly and extensive in purification steps. However, biotechnological method utilizes agricultural and forestry wastes which offer the possibilities of economic production of xylitol by reducing required energy. The precursor xylose is produced from agricultural biomass by chemical and enzymatic hydrolysis and can be converted to xylitol primarily by yeast strain. Hydrolysis under acidic condition is the more commonly used practice influenced by various process parameters. Various fermentation process inhibitors are produced during chemical hydrolysis that reduce xylitol production, a detoxification step is, therefore, necessary. Biotechnological xylitol production is an integral process of microbial species belonging to Candida genus which is influenced by various process parameters such as pH, temperature, time, nitrogen source, and yeast extract level. Xylitol has application and potential for food and pharmaceutical industries. It is a functional sweetener as it has prebiotic effects which can reduce blood glucose, triglyceride, and cholesterol level. This review describes recent research developments related to bioproduction of xylitol from agricultural wastes, application, health, and safety issues.

Lactococcus lactis subsp. lactis is very important as starter culture of cheese and yogurt production. A variety of bacteriocins ranging the molecular weight 3 to 10 have been reported from L. lactis under different growth conditions. In our study, we have optimized the growth of L. lactis for the bacteriocin production. Growth kinetics of these bacteria was studied in accordance to time, pH and temperature. Optimum growth as well as optimum bacteriocin activity was obtained after 18 h at pH 5.0 and temperature 37°C. Bacteriocin activity was produced on optimal conditions and were further characterized and purified. Antibacterial assay of bacteriocin showed the strong growth inhibition of test bacteria. Bacteriocin activities were checked after their treatment with different enzymes, organic solvents, sodium chloride (NaCl) and detergents as well as their heat stability and effect of pH was studied. Bacteriocin activity was found to heat stability at 100°C for 30 min and activity was found stable in the 3 to 10 pH range but lost the activity after the treatment with proteinase-K and protease enzymes. Urea, ethylenediaminetetraacetic acid (EDTA) and 6% affected the bacteriocin activity. Bactericidal activity was further purified to homogeneity by ammonium sulphate precipitation and chromatographic techniques. Molecular weight was calculated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) as 4.6 kDa. Key words: Bacteriocin activity, Lactococcus lactis, growth kinetics, antibacterial assay.