Characteristics and nutritional value of biscuits fortified with debittered salmon (Salmo salar) frame hydrolysate

Effect of debittered salmon frame hydrolysate (DSFH) at various levels (0, 5, 10, 15, 20 and 25 g/100 g) on physicochemical, textural, sensory and nutritional properties of biscuits was investigated. The highest thickness was obtained for the sample with 25 g/100 g DSFH (P < 0.05). There was no difference in diameter among all the biscuit samples (P > 0.05). The samples added with DSFH had lower weight, water activity and moisture content than the control (CONT, without DSFH) (P < 0.05). DSFH at 15 g/100 g showed no detrimental effect on sensory properties of resulting biscuits (DSFH-15). The DSFH-15 biscuit showed reduction in cutting force and fracturability. Scanning electron microscopic and cross-sectional images showed that DSFH-15 biscuit had more porous structure, compared to the CONT. The biscuits fortified with 15 g/100 g DSFH had higher protein but had lower energy value, fat and carbohydrate content than the CONT.     

Total and acid-soluble fluoride content of infant cereals, beverages and biscuits from Brazil

Total fluoride (TF) and HCl 0.01 M ('gastric juice')-soluble fluoride (SF) were analysed in infant foods, beverages and calcium-rich biscuits. Samples were divided into seven categories: children cereals (A), chocolate-flavoured milk (B), soy beverages (C), filled biscuits (D), non-filled biscuits (E), wafer biscuits (F) and corn starch biscuits (G). Mean TF concentrations ± SD (amplitude, unit µg F ml^-1 or µg F g^-1) were: (A) 4.25 ± 3.04 (0.20 - 7.84, n = 6); (B) 0.34 ± 0.47 (0.05-1.27, n = 6); (C) 0.15 ± 0.07 (0.09-0.29, n = 8); (D) 8.44 ± 1.76 (7.65-10.47, n = 4); (E) 12.41 ± 1.15 (10.69-13.68, n = 4); (F) 0.35 ± 0 (0.34-0.36, n = 4) and (G) 7.77 ± 1.12 (6.86-8.68, n = 2). Five samples of cereals, one sample of chocolate-flavoured milk and 10 samples of biscuits were analysed for SF. In cereals analysed for SF, all fluoride was soluble, while for the chocolate-flavoured milk, approximately 50% of TF was soluble. Regarding the biscuits analysed for SF approximately 20% of TF was soluble. It was observed that some of the cereals and beverages, and most of the biscuits analysed, might be important contributors to total daily fluoride intake. When consumed just once per day, cereals and beverages might supply up to 25% of the maximum recommended daily fluoride intake (0.07 mg F kg^-1 body weight) for a 2-year-old child (12 kg). For the filled, non-filled and corn starch biscuits, when 3, 32 or 20 units of them, respectively, are consumed just once per day, they may supply up to 16% of the maximum recommended daily fluoride intake. However, only approximately 25% of fluoride absorption occurs from the stomach and 75% from the small intestine. Therefore, a higher fluoride bioavailability is possible.     

Quality characteristics of biscuits prepared from finger millet seed coat based composite flour

Finger millet seed coat is an edible material and contains good proportion of dietary fibre, minerals and phytochemicals. The seed coat matter (SCM) forms a by-product of millet milling, malting and decortication industries and can be utilised as composite flour in biscuit preparation. The SCM from native, malted and hydrothermally treated millet contained 9.5–12% protein, 2.6–3.7% fat and 40–48% dietary fibre, besides 3–5% polyphenols and 700–860 mg/100 g of calcium. The biscuits prepared using the composite flour were of crisp texture and exhibited breaking strength of 1480–1690 g compared to control biscuits (1560 g). The biscuits were of mild grey colour (ΔE = 40–50) and exhibited higher protein, dietary fibre and calcium contents. The sensory evaluation of the biscuits indicated that 10% of SCM from native and hydrothermally processed millet and 20% from malted millet could be used in composite biscuit flour.     

Structural and physical modifications of corn biscuits during baking process

Colour, crust browning and specific volume of batter is essential to the manufacture of biscuit of good quality, but these properties are rarely measured directly in fermenting batter due to lack of suitable instrumentation. The aim of this study was to systematically evaluate the changes in quality parameters and physical properties of corn biscuits during baking in real time and different oven temperatures using a computer vision system. Colour, crust browning and specific volume of corn biscuits were determined by an image analysis technique using a computerized vision system. Additional quality parameters evaluated were weight loss and firmness of corn biscuit samples. Baking experiments were performed at 190, 210, 230 and 250 °C under natural convection. Colour results showed that it is possible to distinguish two stages in the variation of lightness during the baking time of corn biscuit samples, independently of oven temperature. As a result of the drying effect, it was observed a weight loss and superficial dry layer formation in corn biscuit. The computer vision system can be useful to measure some quality parameters in food products because, among other advantages, it is easy to use, as well as faster and flexible.     

Acrylamide removal from heated foods

The possibility to remove acrylamide from foods by exploiting its chemical physical properties was studied. Commercial biscuits and potato chips were subjected to vacuum treatments at different combinations of pressure, temperature and time. Results showed that acrylamide removal was achieved only in samples previously hydrated at water activity values higher than 0.83, and that, a maximum of acrylamide removal was obtained between 5 and 15 min of vacuum treatment at 6.67 Pa and 60 °C. By applying these process conditions, it was possible to remove 43% and 18% acrylamide from the biscuits and the potato chips, respectively. It was hypothesised that the vacuum treatment could favour acrylamide formation by promoting the decarboxylation of the Schiff base, a key intermediate of acrylamide formation. Although further research is needed to find out for each food category the process conditions that can maximise acrylamide removal while minimising its formation as well as to evaluate the effects on the sensory properties, this technology would represent a promising and alternative strategy to mitigation interventions aimed at reducing acrylamide levels in foods.     

Characterisation of flour, starch and fibre obtained from sweet potato (kumara) tubers, and their utilisation in biscuit production

Sweet potato (kumara) tubers of differing colours (orange, red and white) were used to produce tuber flour, a purified starch fraction and an isolated fibre extract. The fractions from each tuber colour were added into a biscuit mixture, and the effects of tuber source and fraction composition were observed in relation to the physico-chemical characteristics of biscuits. Addition of sweet potato flour and fibre fractions to white wheat flour significantly reduced the pasting properties (peak and final viscosity) of the resulting gels by up to seven-fold compared with the control wheat flour gel (as determined by the Rapid Visco Analyser). The addition of sweet potato starch affected the pasting properties of wheat flour–sweet potato starch mixes to a lesser extent. Biscuit texture (force required to cause a biscuit to fracture) was significantly reduced with the incorporation of sweet potato fibre into the biscuit dough preparation, this was linked to a reduction in biscuit thickness and spread ratio. However, the addition of sweet potato flour and starch resulted in biscuits of similar firmness as the control biscuits.     

sInfluence of starch and protein molecular interactions on the in vitro digestion characteristics of biscuits partially substituted with pulse flours

Recent research has shown that pulse-derived ingredients present a technological alternative to cereals, higher protein and fibre content, and differentiated starch characteristics. In this work, the partial substitution of pulse flours with and without heat moisture treatment (HMT) was evaluated in a biscuit model. The digestion residues at 20 and 120 min that correspond to rapidly, slowly and resistant starch from the Englyst methodology were analysed by DSC, X-Ray and ATR-FTIR. The use of pulse flours in biscuits improved their thermal stability (ΔH = 3.01 and 4.99 J/g for control and Lentil + HMT), preserving a fraction of particularly ling glucans, that influenced the decreasing in the rapidly available starch from 55.26 to 24.11 % (Control and Faba bean + HMT), and enhanced its protein's digestibility from 75.26 to 87.43 % for the same sources. Among pulses, there were similarities regarding their resistance to enzymatic hydrolysis that may help select those with better organoleptic attributes.     

Evaluation of Starch Degradation and Textural Characteristics of Dietary Fiber Enriched Biscuits

Abstract

The effects of dietary fiber inclusion on biscuit texture, cooking properties, and sugar release after in vitro degradation were investigated. Inulin, β-glucan enriched fraction (BGEF), potato fiber, and a resistant starch were used. Effects of the dietary fibers on the pasting properties of flour based mixtures were investigated using a rapid visco analyzer. Results showed a reduction in visco-pasting properties (peak viscosity and final viscosity) of the flour–dietary fiber systems with increasing fiber content. Addition of dietary fiber into the biscuits affected biscuit shrinkage and height development during cooking, as well as generally reducing the resistance of biscuits to snapping during texture analysis tests. Sugar release during in vitro degradation studies showed a highly significant decline when comparing dietary fiber enriched biscuits to the control samples. This would have a beneficial effect in potentially reducing the glycaemic index and subsequent glycaemic loading of such foods.     

Reducing the acrylamide content of a semi-finished biscuit on industrial scale

The baking agent, reducing sugars and organic acids are the ingredients that most influence the acrylamide formation in sweet bakery. Various experiments focusing on these components were performed with biscuits on industrial scale. The replacement of ammonium hydrogencarbonate by sodium hydrogencarbonate reduced the acrylamide content by about 70%. The use of a sucrose solution instead of inverted sugar syrup had a similar effect. Addition of some extra tartaric acid reduced the acrylamide content by about one-third. The positive effects on the acrylamide content were still observed after a second baking process. These results show that mitigation in industry-scale based on the optimization of baking agent, reducing sugars, and organic acid is feasible and compliant to high-quality standards.