Journal of Food Science and Technology

Kakade, R.; Das, H.; Ali, Shaukat

doi: 10.1007/s13197-010-0184-0pmid: 23572767

A double drum dryer working under atmospheric pressure was developed for water evaporation rate of 20 kg/h. Potato slurry of 12% solid concentration was dried to obtain potato flakes. Experiments were carried out at drum speed of 5 to 30 rpm, steam pressure 2 to7 kg/cm2 gauge (saturation temperature 120–164 °C) and liquid level 5 to 10 cm at the nip of drums. The responses obtained were, moisture content of the potato flakes: 1.18–44.15% (db), dry matter output rate: 1.33–2.87 kg dry solid/h and L value of colour: 30.9–66.4. Steam pressure and drum speed were the most influencing parameters affecting all 3 responses. Optimum combination of operating variables for obtaining potato flakes of 8% (db) moisture content, high dry solid output rate and high L value of colour was: drum speed 19.6 rpm, steam pressure 4.3 kg/cm2 gauge (saturation temperature 145 °C) and liquid level at the drum nip 6.3 cm. At this combination of independent variables, residence time of the product on drum surface would be 2 s, final moisture content of product 8% (db), product output rate 2.4 kg dry solid/h and L value of colour 53.

Xiao, W.; Han, X.; Tan, Z.; Tang, S.; Gong, Z.; Bamikole, M.; Ren, G.

doi: 10.1007/s13197-010-0192-0pmid: 23572769

The effects of Ku Ding tea (Lactuca taiwaniana Maxim) and milk powder on biochemical and immunological parameters of Sprague-Dawley rats were investigated and the possibility of use of Ku Ding tea to reduce physiological discomfort of drinking milk powder was assessed. Eighty rats were randomly assigned to four treatments: basal diet (control), basal diet plus whole milk powder (WM), basal diet plus Ku Ding tea (KD) and basal diet plus whole milk powder and Ku Ding tea (MK). Data was collected on animals’ final body weight, hematological values, blood biochemical parameters, antioxidation parameters and immune organ weight index. Results showed that final body weight of male KD was significantly lower than that of WM. White blood cell count, monocyte count and granulocyte count of KD rats were significantly lower than those of WM. Compared to the control, single milk powder supplementation numerically increased plasma malondialdehyde. The malondialdehyde in the male KD and MK rats were lower than those in WM and control, although the differences were not significant. No significant differences were found in Na+K+-adenosine triphosphatase activity, spleen and thymus index in each group. Consumption of Ku Ding tea appeared to lower lipid peroxidation that was induced by milk powder in the rats.

Ariahu, Charles; Abashi, Diana; Chinma, Chiemela

doi: 10.1007/s13197-010-0123-0pmid: 23572770

The kinetics of thermal degradation of ascorbic acid in fluted pumpkin leaves were investigated from 60 to 90°C (pH 5.0 to 6.5). Ascorbic acid degradation was modeled as a first order rate reaction with the rate constants increasing with increase in pH of the medium. The pH and temperature dependence of the rates of destruction gave highly significant correlations when analyzed by the thermal resistance and activated complex reaction rate methods. Activation energy (Ea) ranged from 41.2 to 18.2 kJ/mol while D-values ranged from 103.3 to 22.4 min. The changes in activation energy affected Ko values which ranged from 5.98 × 104 to 41.7 min-1.

Kaur, Manmeet; Oberoi, D.; Sogi, D.; Gill, Balmeet

doi: 10.1007/s13197-010-0126-xpmid: 23572771

Effect of acid modification on physico-chemical, morphological and pasting properties of banana, sweet potato, lotus stem and wheat starches were studied. Results revealed that swelling power, solubility and water binding capacity of all starches decreased by acid modification. By acid modification starch granules from different varieties tended to appear fused and less smooth than the native starch granules. The pasting properties of native starches of all different varieties have significantly decreased following acid modification. Acid modified starches showed higher syneresis as compared to native starches.

Kishore, Kundan; Pathak, K.; Shukla, Rohit; Bharali, Rinku

doi: 10.1007/s13197-010-0189-8pmid: 23572775

Physico-chemical and sensory quality of juice from purple passion fruit under different storage temperature and time were assessed. The maximum loss in fruit weight was recorded under room temperature (25 ± 1°C) followed by at 11 ± 1°C. There was an increase in juice percentage up to 9 and 13 days under room temperature and storage at 11 ± 1°C respectively. The optimum flavour in juice was up to 5 days at 25 ± 1°C and up to 21 days at 8 ± 1°C. A significant reduction in sourness was recorded on 5th day under all treatments and the scores for sourness became almost constant after 17 days. The maximum increase in the mean scores of sweetness on 5th day was observed at 25 ± 1°C followed by at 11 ± 1°C. The optimum level of juice sweetness was maintained up to 21 days at 8 ± 1°C. Total soluble solids content increased in initial stage followed by reduction. There was a reduction in the titrable acidity up to 21 days at 8 ± 1°C. A decreasing trend in the reducing and non-reducing sugar of passion fruit was observed under all the treatments. Fruits stored at 25 ± 1°C, developed off-flavour in juice after 5 days, while storage at 8 ± 1°C produced no off-flavor even up to 21 days. Fruits can be stored for 5 days only at 25 ± 1°C as the overall sensory quality of juice reduced significantly afterwards, while juice maintained the optimum overall quality up to 21 days at 8 ± 1°C.

Sujatha, T.; Narahari, D.

doi: 10.1007/s13197-010-0132-zpmid: 23572777

A study was made on 96 ‘White Leghorn’ hens on the influence of designer diets enriched with omega-3 fatty acids and antioxidants from natural sources on egg yolk composition. The birds were divided into four equal groups viz. Control (without enrichment); FSE − (150 g flaxseeds + 200 mg vitamin E + 3 g spirulina/kg diet); FOSe (20 g fish oil + 0.2 mg organic Se (Sel-Plex) + 3 g spirulina/kg diet) and FSE + FOSe (75 g flaxseed + 10 g fish oil + 100 mg vitamin E + 0.1 mg organic Se + 3 g spirulina/kg diet). All three designer diets increased (p < 0.01) the yolk carotenoid pigments and omega-3 fatty acid levels with proportionate reduction in saturated fatty acid levels and no significant change in the oleic acid levels in the yolk lipids. The three diets also reduced (p < 0.01) the yolk cholesterol levels. Boiled eggs from all four groups had comparable sensory acceptability. Dietary Se and vitamin E supplementation acted synergistically in increasing omega-3 fatty acid levels in the egg.

Kumar, S.; Balasubramanian, S.; Biswas, A.; Chatli, M.; Devatkal, S.; Sahoo, J.

doi: 10.1007/s13197-010-0193-zpmid: 23572778

The nutritional and textural properties of low fat paneer using soy protein isolate (SPI) as fat replacer was investigated. The physico-chemical and sensory characteristics of 4 types of paneer made of low-fat milk (3% milk fat (MF) and 10% solids-not-fat (SNF)) and SPI of 0 (T1), 0.1 (T2), 0.2 (T3) and 0.3% SPI (T4) were compared with high fat paneer (TC) made of high fat milk (6% MF and 9% SNF). CaCl2 (0.2%, w/v) was used as coagulant at 75 ± 1°C. Increased level of SPI in paneer increased yield, protein, ash, moisture content and decreased fat, moisture protein ratio, lactose and calorie contents. Titratable acidity and pH varied in narrow range. Instrumental firmness was higher (p ≤ 0.05) in T1-T4 than in TC. The gumminess, chewiness and firmness showed the same trend. Resilience and cohesiveness values showed no significant difference among the samples. Hunter colour L values showed a decreasing, and a and b values increasing trend with increasing levels of SPI. Sensory appearance and colour scores were lower (p ≤ 0.05) for T1-T4 than TC. More than 0.2% SPI imparted beany flavour to paneer.

Roy, A.; Moktan, B.; Sarkar, P.

doi: 10.1007/s13197-010-0185-zpmid: 23572780

Wadi is a hollow, brittle, ball- or cone-shaped popular traditional legume-based product of many countries in the Indian Subcontinent. To prepare wadi, blackgram (Phaseolus mungo L.) dhal (dehusked split seeds) was soaked, ground to a soft dough, fermented for 10 h in a closed container, moulded into balls or cones and dried for ~60 h (repeating a cycle of 8 h sun-drying at 29–33 °C and then 16 h shade-drying at 28–30 °C). This study aims at understanding the fate of some selected foodborne bacterial pathogens during a chance contamination of blackgram dough at the time of preparing wadi. Uninoculated dough, during the course of its processing to wadi, remained free from Staphylococcus aureus and Escherichia coli, but got contained by Bacillus cereus during the first 10 h of fermentation and also the next 24 h of drying wadi. B. cereus, when spiked into freshly prepared dough at a load of 5.2 log cfu/g, also diminished after 24 h of drying (detection limit (DL), 100 cfu/g). S. aureus (DL, 100 cfu/g) and E. coli (DL, 10 cfu/g) reached below the DL after 36 h of drying. After 10 h of fermentation and 36 h of drying, the moisture content decreased from initial 61.9 to 33.5%, and the pH declined from 6.0 to 4.8.