Heat–Moisture Treatment on Pinhão Starch Impacts the Properties of the Biodegradable Films

Using non-conventional starch can benefit the industry since it can present different properties. It also can lead to new properties upon physical modification, which improves its derivate film properties. Therefore, the aim of this work is to evaluate the heat–moisture treatment (HMT) on pinhão starch and its effectiveness in film properties. After isolation using water as a solvent, the pinhão starch is treated by HMT for 16 h at 110 °C. Native and HMTed starches are used to produce biodegradable films. Pinhão starch and starch films chemical and physical properties are properly characterized. The HMT causes some changes in short-range ordered structures, reduces the relative crystallinity, and shifts the pinhão starch from C-type to A-type. Also, HMT decreases the peak viscosity and the breakdown, and improves thermal stability. These starch changes upon HMT reduces water vapor permeability, increases tensile strength, and elongation at the break of pinhão starch films. Desirable changes in starch and film properties are achieved by physically modifying pinhão starch using HMT, which is a promising alternative to chemical modifications.     

Molecular structure and granule morphology of native and heat‐moisture‐treated pinhão starch

Pinhão seed is an unconventional source of starch and the pines grow up in native forests of southern Latin America. In this study, pinhão starch was adjusted at 15, 20 and 25% moisture content and heated to 100, 110 and 120 °C for 1 h. A decrease in λ max (starch/iodine complex) was observed as a result of increase in temperature and moisture content of HMT. The ratio of crystalline to amorphous phase in pinhão starch was determined via Fourier transform infra red by taking 1045/1022 band ratio. A decrease in crystallinity occurred as a result of HMT. Polarised light microscopy indicated a loss of birefringence of starch granules under 120 °C at 25% moisture content. Granule size distribution was further confirmed via scanning electron microscopy which showed the HMT effects. These results increased the understanding on molecular and structural properties of HMT pinhão starch and broadened its food and nonfood industrial applications.     

Rat bioassay of the protein nutritional quality of soy-fortified sorghum biscuits for supplementary feeding of school-age children

BACKGROUND: Protein–energy malnutrition (PEM) remains a major deficiency disease among children in developing countries. The protein nutritional quality of soy‐fortified sorghum biscuits was evaluated with respect to their potential as a protein‐rich supplementary food. Three isonitrogenous diets based on 50:50 ratio decorticated sorghum:defatted soy flour biscuits, 100% sorghum biscuits, casein, and a protein‐free diet were fed to male Sprague Dawley weanling rats. RESULTS: Protein efficiency ratio (PER) for the sorghum–soy biscuit diet was equivalent to the reference casein diet, and zero for the 100% sorghum diet. Faecal bulk for 100% sorghum diet was 1.5 times higher than sorghum–soy and casein diets. True protein digestibility of the three diets was high—88–95%—agreeing with previous rat studies with sorghum. Biological value and net protein utilization of the sorghum‐soy biscuit diet were similar to the casein diet, but lower than the 100% sorghum biscuit diet CONCLUSION: Notwithstanding limitations of rat bioassay for assessing sorghum food protein quality, the high PER of defatted soy flour‐fortified sorghum biscuits (sorghum:soy 50:50 ratio) indicates they have considerable potential as a supplementary food to young children to alleviate PEM. Copyright © 2011 Society of Chemical Industry     

Mass Production Method for Rice Protein Isolate and Nutritional Evaluation

We developed a method for mass production of rice protein isolate (RPI) and evaluated its nutritional quality in rats. To obtain thick slurry, rice flour was mixed with a 0.6% Termamyl 120L-solution (1:2, w/v) at room temperature (～23°C). The slurry was heated at 97°C for 2 hr with stirring. Gelatinization and liquefaction occurred simultaneously. RPI obtained by filtration and washing with boiling water, was more than 90% pure protein (dry matter basis). It also contained 6.4% dietary fiber, 1.3% ash, and 1.1% carbohydrate. RPI diets (40–50%) allowed the maximum growth in rats comparable to that with 25% casein diet.     

Utilization of protein concentrates from ungerminated and germinated fluted pumpkin (Telfairia occidentalis Hook) seeds in cookie formulations

Cookies (soft type biscuits) were produced from blends of wheat flour containing graded levels (0–25%) of protein concentrates prepared from ungerminated and germinated fluted pumpkin (Telfairia occidentalis Hook) seeds and evaluated for nutritional, baking and sensory properties. Protein quality was investigated using weanling albino rats fed diets that were formulated to supply 10% protein using cookie samples, with casein as a control. Cookies produced from blends containing protein concentrates from germinated seeds had higher contents of crude protein and lower levels of polyphenol and phytic acid, compared with cookies supplemented with concentrates from ungerminated seeds. The use of up to 15% concentrate from ungerminated seeds in the blends produced cookies with spread ratio, hardness, colour and flavour similar to the 100% wheat flour (control) cookies. Cookies supplemented with concentrates from germinated seeds at 15–25% levels were nutritionally comparable to diets based on casein, but at the expense of acceptability. Copyright © 2004 Society of Chemical Industry     

Isolation and Characterization of Starch from Seeds of Araucaria brasiliensis: A Novel Starch for Application in Food Industry

The pinhão seeds (Araucaria angustifolia), are composed of 34% of starch and very low fractions of protein, lipids and phenolic compounds. This composition is favorable to obtain a stable, white in color and odorless starch, useful in the food industry. The isolated starch is constituted predominantly of small‐sized round granules (10–25 μm), rather than oval ones. Compared to corn starch, pinhão starch has a lower temperature and enthalpy of gelatinization. Retrogradation occurs to a lower extent in pinhão starch, due to its lower amylose content (∼25%). The pasting profile of pinhão starch showed a higher consistency than that of corn starch, with lower temperature in the peak of maximum viscosity. The higher swelling and solubility values of pinhão starch, in conjunction with the higher storage modulus (G') suggest new different applications of this novel starch. The low protein content of the starch granule favors applications like production of glucose and fructose syrups. The simple method of extraction and the high yield of starch from pinhão seed might be attractive not only for pilot‐plant but also for commercial‐scale production.     

Physicochemical,crystallinity, pasting and thermal properties of heat‐moisture‐treated pinhão starch

The effect of heat‐moisture treatment (HMT) on the properties of pinhão starches under different moisture and heat conditions was investigated. The starches were adjusted to 15, 20 and 25% moisture levels and heated to 100, 110 and 120°C for 1 h. The X‐ray diffractograms, swelling power, solubility, gel hardness, pasting properties and thermal properties of the native and HMT pinhão starches were evaluated. Compared to native starch, there was an increase in the X‐ray intensity and gel hardness of HMT starches, with the exception of the 25% moisture‐treated and 120°C heat‐treated starch. HMT reduced the swelling power and solubility of the pinhão starches when compared to native starch. There was an increase in the pasting temperature, final viscosity and setback and a decrease in the peak viscosity and breakdown of HMT pinhão starches compared to native starch. HMT increases the gelatinisation temperature of native pinhão starch and reduces gelatinisation enthalpy.     

Nutritional assessment of cookies supplemented with defatted wheat germ

Replacement of wheat flour with defatted wheat germ (DFWG) at levels of 0–25% was investigated for its effect on functional and nutritional properties of cookies. The crude protein content of DFWG was as high as 27.8% with a highly valuable amino acid profile, rich in essential amino acids, especially lysine (2.32 g/100 g). The physicochemical and sensory evaluation of cookies, revealed that up to 15% substitution of wheat flour with DFWG produced acceptable cookies similar to the control (100% wheat flour) cookies. The protein quality of the cookies was assessed through weanling albino rats by feeding a diet of cookies for 10 days, which was formulated to supply 10% protein, with a casein diet as a control. The cookies containing 15% DFWG, were best regarding protein bioavailability in rats. The protein efficiency ratio (PER), net protein utilization (NPU), biological value (BV) and true digestibility (TD) differed significantly among diets containing cookies with 0–10% DFWG, and casein diet when fed to rats. Diets containing 15% DFWG have values, of these parameters, similar to the casein diet.     

The quality and sensory attributes of cookies supplemented with fluted pumpkin (Telfairia occidentalis Hook) seed flour

Replacing wheatflour (WHF) with defatted fluted pumpkin (Telfairia occidentalis Hook) seed flour (FPF) at levels of 0–25% was investigated for its effect on chemical, physical, sensory and nutritional properties of cookies (biscuits). Protein quality was evaluated by using weanling albino rats fed a diet of cookies, which were formulated to supply 10% protein, with a casein diet as a control. Up to 15% substitution of WHF with FPF produced acceptable cookies with spread ratio, hardness, colour and flavour similar to the control (100% WHF) cookies. Use of higher levels (20–25%), however, resulted in reduction in these quality attributes. When WHF was replaced with 15% FPF, there was an increase of 84.6% in crude protein, 62.9% in calcium, 131.0% in potassium and 61.6% in phosphorus contents of composite cookies. There were no significant (P > 0.05) differences between the values obtained for protein efficiency ratio, net protein ratio and true digestibility of cookie diets containing 15–20% FPF, and casein when fed to rats.     

Characterization of Pinhão Starch. Part I. Extraction and Properties of the Starch Granules

The starch fraction of Pinhão, the seeds of Pinheiro do Paraná (Araucaria angustifolia, Bert, O. Ktze) was easily extracted and represents 21.87% of total weight. The low content of protein, fat and ash accounts for the efficiency of the extraction and purification. Pinhão starch shows an amylose level and strong anionic characteristic similar to corn starch. The round-shaped granules are smaller than those of cassava and similarly resistent to DMSO solubilization, what suggests a very homogenous granular structure.     

The effect of formulated goats' milk on calcium bioavailability in male growing rats

BACKGROUND: There are two main proteins in milk; whey and casein. Casein contains casein phosphopeptides (CPP), which are released on digestion of the milk. These may increase calcium solubility by binding calcium in the small intestine. Thus increasing casein in the diet may help to stimulate bioavailability of calcium and increase bone density. The present study tested this hypothesis in growing male rats fed diets containing three different concentrations of casein from goat milk. RESULTS: Rats fed the diet containing no casein had significantly lower calcium absorption when compared to rats fed the diets that contained 80% and 57% of goat milk protein as casein; however, no significant difference was observed between rats fed diets with 80% and 57% casein. The varying amounts of casein had no effect on mineral uptake or retention in the femur. Biomechanical testing and mineral analysis of the femurs showed no differences between diet groups. The mechanism to explain this lack of retention remains unclear. CONCLUSION: The diets containing 80% and 57% of goat milk protein as casein delivered increased calcium absorption compared to the diet containing no casein, suggesting a minimum level of casein is needed to optimize calcium absorption from goat milk. Copyright © 2009 Society of Chemical Industry     

The effect of digesta sampling time and dietary protein source on ileal nitrogen digestibility for the growing rat

The effect of time that digesta were collected on the quantity and representativeness of ileal digesta and on the determination of apparent and true ileal nitrogen (N) digestibility for growing rats was investigated. Semi‐synthetic diets containing chromic oxide as an indigestible marker were given to 200 g live weight rats for 8 days as a single daily meal. The experimental treatments comprised six diets (lactalbumin, soy protein isolate, wheat gluten, fish, protein‐free (PF), enzymically hydrolysed casein (EHC)) and four ileal digesta sampling times (3, 4, 5 and 6 h after the start of feeding). On the eighth day the rats were fed and slaughtered according to treatment, and digesta were sampled from the terminal ileum. Endogenous ileal nitrogen excretion was determined using both the protein‐free and peptide alimentation methods. There was a significant (P = 0.027) effect of experimental diet averaged across sampling times for chromium recovery (CrRec). The CrRec was higher for the rats fed the PF diet than for the other diets. Responses to sampling time varied significantly (P < 0.05) among diets for ileal digesta weight (IDW), nitrogen/chromium (N/Cr) ratio, ileal digesta weight relative to dry matter intake (IDW/DMI), CrRec, N flow, apparent N digestibility and true N digestibility (determined using the protein‐free method). The optimal digesta sampling times for each of the diets were 3 h for PF, EHC, lactalbumin and fish and 4 h for soy protein isolate and wheat gluten. Consequently, 3 or 4 h after the start of feeding is recommended as the optimum ileal digesta sampling time for most purified protein sources when fed to the growing rat as a single daily meal. © 2002 Society of Chemical Industry     

EVALUATION OF THE NUTRITIONAL QUALITY OF NONTOXIC KERNEL FLOUR FROM JATROPHA CURCAS L. IN RATS

ABSTRACT

The origin of Jatropha curcas L. is in Central America, probably Mexico, although it is also distributed in South America, Africa and Asia. In Mexico, it grows as nontoxic and toxic J. curcas genotypes. In this work, the protein quality including protein efficiency ratio (PER), net protein ratio (NPR) and true digestibility (TD) of nontoxic genotype defatted flour was assessed using Wistar rats. The probed diets contained flour (3), flour‐lysine, 1% (4), flour‐phytase, 500 FTU (5) and two control diets: nitrogen‐free (1) and casein (2). The rats were fed for 28 days. The PER (1.37, 1.77 and 1.61) and NPR (1.80, 2.29 and 2.12) obtained values for diets (3.4 and 5) were lower than those obtained for casein (2.07 and 2.46), respectively. No statistical differences were found in TD.

PRACTICAL APPLICATIONS

Jatropha curcas defatted flour may be used in the food industry for the development of diets for human and animal consumption. Besides achieving fortification of foods that are made from wheat, which has a low protein content, with the addition of Jatropha meal, these foods will improve the protein quality of many food products.     

Hypolipidemic effect of enzymatically extracted sunflower seed protein fraction

An attempt was made to enzymatically extract the protein fraction (PF) from sunflower seeds and investigate its dietary effect on the growth, plasma and tissue lipid profiles, plasma protein content, erythrocyte membrane lipid profile and organ weights of rats. Extraction of dehulled sunflower seeds in an aqueous medium in the presence of the enzyme pectinase at 50 ± 1 °C and pH 4.5 yielded a protein fraction with low residual chlorogenic acid and fibre contents. Rats fed the sunflower seed protein fraction showed a similar body weight gain and food efficiency ratio as rats fed casein. However, the different dietary proteins had different effects on plasma total cholesterol and triglyceride contents. The rats fed the sunflower seed protein fraction showed a significant decrease in plasma cholesterol (p < 0.02) and triglyceride (p < 0.02) concentrations compared to the casein‐fed rats. The PF‐fed rats also exhibited a significant difference in erythrocyte membrane phospholipids and phosphatidylcholine/phosphatidylethanolamine ratio. Rats fed the different dietary proteins did not show much variation in plasma protein content, liver and brain lipids and organ weights. These results demonstrate the hypolipidemic action of the sunflower seed protein fraction and that it can be considered a suitable edible protein like casein. © 2000 Society of Chemical Industry     

Effects of highly purified sardine proteins on lipid peroxidation and reverse cholesterol transport in rats fed a cholesterol-rich diet

The effect of highly purified sardine proteins was compared with that of casein on serum and lipoproteins lipid peroxidation and reverse cholesterol transport. Lecithin:cholesterol acyltransferase (LCAT) activity, high density lipoproteins (HDL₂ and HDL₃) composition and serum lipid and lipoproteins peroxidation were determined in rats fed a cholesterol-rich diet. Hypercholesterolemic rats were divided into two groups fed diets enriched with cholesterol and containing 20% of highly purified sardine proteins (SPc) or casein (CASc) for 28 days. A control group was fed a standard diet (CAS). Compared with CAS and CASc, the thiobarbituric acid reactive substances (TBARS) concentrations of low density lipoprotein (LDL)–HDL₁ in SPc were 3.5- and 1.7-fold higher compared with casein diets. TBARS in HDL₂ and HDL₃ were, respectively, 2.3- and 1.6-fold lower in SPc compared with CASc. In SPc group, LCAT activity was higher compared to CASc and CAS (P < 0.05). Purified sardine proteins had no beneficial effects on LDL-cholesterol and lipid peroxidation. However, they reduced HDL oxidation and improved reverse cholesterol transport, in the hypercholesterolemic rat.     

Thermodynamic properties of moisture desorption of raw pinhão (Araucaria angustifolia seeds)

The seeds of Araucaria angustifolia, named pinhão, are consumed in the south and southeast of Brazil. They are big in size and have high nutritious value. The literature about technological aspects of pinhão is very scarce and there are no reports about moisture sorption models. In this work, moisture desorption isotherms of raw pinhão were determined at 15, 25, 30 and 40 °C. Results show that temperature has little effect on the sorption behaviour and the Chirife model was found to best represent the experimental data. The isosteric heat of sorption (differential enthalpy) was calculated through direct use of moisture desorption isotherm by applying the Clausius‐Clapeyron equation. The differential enthalpy of desorption decreased with increasing moisture content. The enthalpy–entropy compensation theory was applied to desorption isotherms and plots of differential enthalpy vs. differential entropy for pinhão provided the isokinetic temperature, indicating an enthalpy‐controlled desorption process.     

Protein conversion efficiencies of four test diets based on milk, two milk and tea treatments, and casein

Milk consumption in 80 households in western Kenya averaged .25 to 1.00 L per family per day. Most of this milk was processed into a milk and tea beverage. Polyphenols, the major determinants of tea flavor and character, form soluble complexes with casein when black tea infusions are mixed with milk. Test diets were prepared from the following treatments: a) casein reference diet; b) milk, no tea leaves; c) milk added after heat treatment; and d) traditional Kenyan-style tea (i.e., milk and tea leaves heated together). Four groups of 10 male 21-day-old Sprague Dawley weanling rats were assembled and assigned to the test diets. Weight gain and protein intake (g/g) during a 28-d test period for the four diets were 1.94, 2.99, 2.93, and 2.77. The least significant difference test showed weight gain for protein intake was greater for rats on the milk-based diet and the diet with milk added after heating than for rats on the traditionally prepared milk and tea drink. Rats did most poorly when assigned to the casein reference diet. Modification of traditional Kenyan tea preparation practices (i.e., adding milk after tea leaves have been removed) might improve the nutritional value of the most popular milk product in western Kenya.     

Effect of cellulase/glucanase/xylanase (Roxazyme G2) enzymes combination on nutrients utilisation of vegetable meal (Amaranthus cruentus) fed as sole dietary protein source in rat assay

Amaranthus cruentus vegetable meal (ACVM) had 23% crude protein. Ca, Na, K, Mg and Fe were abundant at 2.0 g kg^?1, 7.1 g kg^?1, 4.8 g kg^?1, 2.5 g kg^?1, 1109 mg kg^?1, respectively. P‐phosporous, oxalates and tannins were noticeable. Lysine, methionine and cystine were limiting. Weight gain for rats on the reference (casein) diet 2 at 6.30 g ±2.87 was highest (P < 0.05) followed by diet 6 (12% ACVM with enzyme supplementation) at 5.01 g ±2.42. Feed intakes were similar (P > 0.05) for rats on the reference diet and for rats on 10% and 12% with/without enzyme supplementation ranging from 42.90 g ± 4.52 in reference diet to 45.12 g ± 3.64. Nitrogen retention was highest for rats on reference diet but similar (P > 0.05) to rats on 12% enzyme supplemented diet at 0.53 ± 1.12 and 0.53 ± 2.10, respectively. Other investigated protein evaluation parameters revealed similar results among rats kept on reference diet and the rats on ACVM based diets with enzyme supplementations. Enzyme supplementation had a complimentary role in ACVM nutrition in rat trial.     

Effect of soy protein supplementation on the nutritive value of ‘gari’ (farina) from Manihot esculenta

The supplementary role of soy protein on cassava (Manihot esculenta) “gari” or farina was studied in 35 day-old albino rats of the Wistar strain (n=6 per group) for 10 days. Gari was supplemented with soy beans at 10 and 15% soy protein levels to produce “soy gari” and the performances of rats fed the test diets compared with those on a 10% casein diet. Protein efficiency ratio (PER), Net protein utilization (NPU), true digestibility (TD) and biological values (BV) were the parameters used to assess the nutritional performance of the diets based on weight gains and nitrogen balance. The PER for 10% casein, 10 and 15% soy protein-supplemented gari groups were 2.31, 1.85 and 1.94 respectively, while the corresponding values for NPU were 71.9, 65.8 and 64.1, respectively. The TD values for the 10% casein, 10 and 15% soy protein-fed rats were 97.2, 91.9 and 90.0, respectively, while the corresponding values for BV were 73.9, 70.9 and 71.5. The PER, NPU, TD and BV for 10% casein diet were significantly superior (P<0.05) to those of the soy gari diets which gave NPU, TD and BV values 89–97% of those of the casein diet. There were no significant differences (P>0.05) in these parameters between the 10 and 15% soy protein supplementation. Soy gari is safe to the consumer, because the procedures involved in processing soy beans and cassava ensure the elimination of toxic anti-nutritional factors known to impact negatively on nutrient availability, metabolic processes and growth. It is suggested that the consumption of soy gari at 10% soy protein supplementation be promoted in gari-eating areas, to ameliorate the endemic problems of protein deficiency disorders.     

Nutritional quality of storage proteins during germination of Indian bean (Dolichos lablab. var. lignosus) seeds

The dry Indian bean seed composed of starch is the major component (33%) and protein accounted for 25% of dry weight. The ability of germination to increase the nutritional quality of storage proteins was studied by germinating the Indian bean seeds for 0, 8, 16, 24 and 32 h and evaluated the nutritional quality through an in vitro protein digestibility (IVPD), protein efficiency ratio (PER), apparent and true digestibility. The IVPD of raw Indian bean seeds by pepsin alone was 60.12% and the digestibility by pepsin and trypsin together improved to 64.24%. The in vitro digestibility by both processes increased appreciably with germination and marked increase was noticed in the early stage of germination. The PER values followed the same pattern as the value of weight gain of rats fed with diets containing raw and germinated Indian bean. The lowest PER values were observed with raw bean diet. However, the value increased in rats fed with diets of Indian bean germinated for different intervals of time, reaching comparable PER values with the group maintained on casein diet. The true and apparent nitrogen digestibility of raw bean low being only 82 and 72%, respectively observed with casein diet. Diets with germinated bean protein showed a marked increase in both parameters, although the values were still less than that displayed by the casein fed rats. Germination is a simple biochemical enrichment tool and significantly improves palatability, digestibility and the nutritive utilisation of proteins in Indian bean seeds.