ABSTRACT
The aim of this study was to analyze the impact of traditional and combined pretreatment on dehydration kinetics and quality of dried swamp cranberries. Fruits were blanched, cut, or treated by combined technique consisting of blanching and application of pulsed electric field. Afterwards, fruits were subjected for osmotic dehydration (OD; 72 hr) in 61.5% sucrose solution or in ternary solution consisting of 30% sucrose with 0.1% addition of steviol glycosides to ensure similar sweetness of both mixtures. In the case of samples treated by combined method, OD was enhanced during first 30 min by sonication. Partially dehydrated cranberries were air dried at 70 °C. The quality of dehydrated fruits was assessed by the means of phenolics content, anthocyanin content, flavonoid content, vitamin C content, water activity, and color. Blanching decreased drying time by 48% to 50% in comparison to cutting. Utilization of combined method reduced drying time of cranberries up to 55% in comparison to cut samples. Water activity of all samples was below 0.6. Blanched samples or blanched and then treated with pulsed electric field and ultrasound contained more anthocyanins and flavonoids and less sucrose than cut samples. PRACTICAL APPLICATION: According to current trends in food and beverage industry, consumers seek for products which does not contain excessive amounts of sugars, salt, or fats. Dried cranberry fruits are rich in bioactive compounds and need to be osmotically dehydrated in sugar solutions to make the taste of the final product acceptable. Osmotic dehydration is also carried out to decrease time of drying, which is one of the most energy intensive processes. Therefore, there is a need to develop a technology with potential to maintain the bioactive compounds, reduce sugar content in comparison to traditionally process fruits, and enhance the kinetics of drying.
Subject(s)
Desiccation/methods , Food Preservation/methods , Vaccinium macrocarpon/chemistry , Animals , Anthocyanins/blood , Ascorbic Acid/chemistry , Color , Flavonoids/chemistry , Food Preservation/instrumentation , Fruit/chemistry , Kinetics , Osmosis , Phenols/chemistry , Quality Control , TasteABSTRACT
To study the influence of physical activity and certain dietary habits on cardiovascular risk factors in middle age men, healthy male workers were subjected to a physical activity inquiry, dietary recall, inquiry about smoking habits and anthropometric assessment. Also, blood pressure was measured and a fasting blood sample was obtained to assess serum total and HDL cholesterol, triglycerides and blood glucose. Multiple stepwise and canonical regressions were used to analyze data. Four hundred eleven subjects aged 46.8ñ10 years were studied. Twenty four percent smoked, mean body mass index was 26.4ñ2.6, mean caloric intake was 11.7ñ3 MJ/day and mean caloric expenditure 10.6ñ1.1 MJ/day or 1.52ñ0.13 times the resting metabolic rate. Physical activity, body mass index and fiber intake appreared as independent but weak predictor of total and LDL cholesterol. Alcohol intake, age and body mass index were predictors of HDL cholesterol and blood pressure was predicted by age, fiber intake and body mass index. Canonical analysis showed that 54 percent of blood pressure variation is explained by age, body mass index and fiber intake and in 31 percent of HDL cholesterol variation is explained by alcohol intake. Physical activity has a weak influence on serum total and LDL cholesterol. Alcohol intake is the main predictor of HDL cholesterol in these workers
