Quality Characteristics of shortbread Biscuit Fortified with Fermented Jack bean Flour

Biscuit are usually produced from wheat fl our, increasing cost and limited supply of wheat demand that attention be given to the application of indigenous grains to totally or partially replace wheat in bakery products. This study evaluated the effect of substituted fermented jack bean fl our (FJF) on wheat fl our on proximate, mineral, physical and sensory properties of shortbread biscuit (SBB). Jack beans were soaked in water (6 h), de-hulled, re-soaked (12 h), sundried (3 days), oven-dried (55 °C, 24 h), milled, sieved and packaged for further processing. Shortbread biscuits (SBB) were produced using different levels of wheat fl our substituted with FJF in 10% and 20% and using wheat fl our as control. Sensory evaluation of the biscuits was carried out using 5 point hedonic scale. The data obtained during the study was analyzed statistically using analysis of variance. Proximate composition, mineral, physical characteristics and sensory properties of the biscuit samples were determined. Moisture, crude protein, crude fi bre, fat, ash and carbohydrate of the SBB ranged from 6.85-8.77, 8.41-10.17, 1.58-2.14, 18.39-19.42, 1.81-2.11 and 59.49-61.51%, respectively. Addition of FJF signifi cantly increased the Ca (0.11 %), P (6.38 %), Mg (0.18 %), Fe (2.29 %) and Mg (2.18 %) of the SBB compared to values obtained from 100% wheat fl our. SBB with 20% FJF had the highest spread factor and spread ratio of 5.73 and 6.62, while SBB with 10% FJF had the least value. Sensory evaluation showed that SBB with 10 % FJF was preferred in terms of fl avour, mouth feel and overall acceptability. It was concluded that substitution of FJF into wheat fl our gave the biscuit with the best overall quality acceptability. Research Article Quality Characteristics of shortbread Biscuit Fortifi ed with Fermented Jack bean Flour Ogori Akama Friday1*, FF Ajayi1, OA Folorunsho2 and AF Ogori1 1Department of Home Science, Federal University Gashua, P.M.B. 1005, Yobe State 2Department of Home Science, Nasarawa State University, Keffi , Nasarawa State Dates: Received: 01 June, 2017; Accepted: 24 July, 2017; Published: 26 July, 2017 *Corresponding author: Ogori Akama Friday, Department of Home Science, Federal University Gashua, P.M.B. 1005, Yobe State, E-mail: https://www.peertechz.com


Introduction
The bakery industry is growing very fast and the products are increasingly becoming popular among all sections of people. Among ready-to-eat snacks, biscuits possess several attractive features including wider consumption base, relatively long shelf-life, more convenience and good eating quality [1,2]. They are traditionally made from soft wheat, a cereal, which is cultivated in many parts of the world, but imported by countries with unfavorable climatic conditions. Such importing countries spend a lot of foreign exchange on importation of wheat. There is a compelling need to develop an adequate substitute for wheat, as the demand and price of this product could further be increased by natural disasters such as hurricanes, which destroy wheat crops and also the fact that many farmers are beginning to switch from growing wheat to growing "more lucrative" crops (like corn and soy beans), which could be used in the production of biofuels. In the quest for a wheat substitute, flour with better nutritional quality than wheat would be highly desirable, especially in developing countries where malnutrition is prevalent [3].
Composite fl our bakery products have manifold advantages, apart from extending the availability of wheat fl ours; these are looked upon as carrier of useful functional food components and nutrients [4].
Jack bean (Canavalia ensiformis) is one of the under exploited tropical dry beans. It is usually used in Nigeria as an ornamental plants, grown near houses and allowed to trail on walls and trees [5]. It is, however, fairly widely distributed, being cultivated in Africa, Asia, the West Indies, Latin America and India. The jack bean can be grown in marginal soils and arid to semi-arid regions not suitable for common legumes such as Phaseolus and Vigna species. It has, therefore, great potential in most tropical and subtropical parts of the world [6]. The seed of jack bean, the highly produced large seeded tropical legume, contains about 300 g/kg crude proteins and 600 g/ kg carbohydrates [7]. Canavalia ensiformis ranks among the underutilized legumes that could ameliorate protein defi ciency in human nutrition, particularly in developing countries.
Processing techniques such as germination and fermentation have been found to improve the quality of cereals and legumes due to chemical changes that enhance contents of free sugars, protein and vitamins, as well as bioavailability of minerals [8,9,10], reported that germination induces an increase in free limiting amino acids with modified functional properties of seed components [11], have also reported that fermentation of grains improves amino acid composition and vitamin content, increases protein and starch availabilities and lowers levels of anti-nutrients. It is therefore expected that composite flour produced from germinated cereals and fermented legumes will have the advantage of improving overall nutrition.
As there is a growing interest in the production of baked products, biscuit are usually produced from 100% wheat fl our which do not contain the required balance essential amino acid for human. There is need to fortify wheat fl our with the readily available jack bean seed fl our for high nutrient and higher quality product. This study was undertaken to produce short-bread biscuit of acceptable quality from fermented jack bean fl our and wheat fl our blends without affecting its sensory attributes. Thus, the objective of this study was to produce shortbread biscuit fortifi ed with fermented jack bean seed fl our and to evaluate its physicochemical and sensory properties.

Materials
Jackbean (Canavalia ensiformis) seeds of white variety were purchased from retail stocker at Alamis market in Lafi a, Nasarawa State, Nigeria. Wheat fl our (Triticum aesticum), sugar, baking powder, vanilla essence, common salt, margarine, nut meg and rice fl our were purchased from a commercial stocker in Lafi a main maket, Nasarawa state, Nigeria. All laboratory reagents used for the analysis in this work were all of analytical quality.

Processing of jackbean seeds into fermented jack bean fl our
The processing of Jack bean seeds was done using spontaneous fermentation. This semi-solid state fermentation involves washing and removing stones, dirt, and other debris from the beans. The jackbean was weighed, soaked in excess cold water for six (6) hours to soften the seed coats and leach out colouring matter and substances that impact beany fl avour in the fl our, and dehulled manually and it as re-soaked in cold water for twelve (12) hours for fermentation take place and washed severally in clean water, sun dried for three (3) days and oven-dried (55 0C) for 72 hours to take care of any surface spoilage micro-organism adhesion. Then milled into fi ne fl our and stored in polythene bag.

Preparation of shortbread biscuit
Samples of shortbread biscuits were prepared by fi rst blending each of the fl our blends in table 1, with other ingredient which include caster sugar (250g), margarine (375g), baking powder (2g), table salt (5g), rice fl our (137g) vanilla essence and nut meg (1 whole seed) and then formed into barters of 4mm×5mm×2mm in shape. These were proofed for 10 mins and baked at oven temperature of 180 0 C for about 1 hour. After baking, biscuit were exposed to cool in tray for 4 hours and then packed in polythene bags and stored in dry container for nutrient analysis and sensory evaluation.

Sample analysis
Flour and biscuit: Moisture was determined by hotair oven drying at 105 0 C to constant weight [12]. Ash, protein (microKjeldahl, N × 6.25), crude fi ber and fat (Solvent extraction) were determined by the [12], methods. Calorie was calculated using Atwater factors of 4 × % Protein, 4 × % carbohydrate and 9 × % fat and then taking the sum. Magnesium and Zinc were determined by fl ame photometry using a fl ame photometer as described by the [12], methods. Phosphorous was determined by the molybdovanadate method [12]. Calcium and Iron was determined using atomic absorption spectrophotometer [12].

Determination of physical analysis of biscuit
Cookies diameter and thickness were determined using vernier callipers, while cookies weight was determined using an electronic weighing balance. Spread ratio was expressed as diameter/thickness [13].

Sensory analysis
The samples were evaluated by thirty (30) panelists. The panelist were instructed to evaluate the organoleptic quality (i.e. color, texture, fl avor, mouth feel and overall acceptability) using a fi ve-point hedonic scale where fi ve represents like extremely and one represent dislike extremely. Consumer testing was conducted at the home economics sensory analysis laboratory. The products were served to each panelist in similar sample retaining plate. The panelist were instructed to rinse their mouth with warm water which was provided to each of them before and after testing a product to avoid carry over effect.

Experimental design
The experimental design used was a completely randomized design (CRD) model with factorial experiment

Statistical analysis
Data obtained for proximate, mineral, physical properties and sensory analysis of biscuit sample was statistically analyzed using analysis of variance (ANOVA) of SPSS version 16. Least signifi cant difference (LSD) test was used to estimate the signifi cant differences among the means at 95% confi dence level.

Results and Discussion
The results obtained from the proximate analysis of wheat The crude protein content of un-defatted jack bean fl our was found to be higher than that of wheat fl our. The crude protein content of un-defatted jack bean seeds (29.24 %) was found to be comparable with that of earlier reports on the same Jack bean (29.8 %) by [16]. According to [17], higher level of protein content of seed materials of Canavalia ensiformis has nutritional signifi cance, since moderate intake of these seeds will greatly increase the total dietary protein intake of the consumers.
Fibre helps in the maintenance of human health and has been known to reduce cholesterol level in the body. The value obtained for crude fi bre of un-defatted (2.21 %) and de-fatted bean seeds (2.22 %) was close with the value obtained for raw jack bean seed 2.55 % [23], but lower than the value reported earlier on jack bean (4.71-11.4%) by [18].
The fat content value of un-defatted (1.84 %) and defatted (1.36 %) jack bean fl our were found to be lower than Cassia fl oribunda (2.1-3.1%) reported by [19], Canavalia gladiata (2.46%) [20], and Canavalia gladiata (2.8-3.8%) [21]. The ash content gives an idea of the amount of inorganic content of the sample from where the mineral contents could be obtained.
However, the value obtained for ash content of un-defatted jack bean fl our (5.24 %) was similar to the fi ndings 5.80% reported for Cajanus cajan [22].     [27], reported that using whole grain raw materials and combining wheat fl our with certain legumes and pseudocereals in biscuit production, resulted in improved nutritional and functional properties of the fi nal product ( Table 4).
The calcium content obtained for shortbread biscuit ranged Sample C (20 % fermented jackbean fl our) had higher value of spread ratio (6.62 mm) than control (6.02 mm). The value observed from this study is similar to the fi ndings of Ho and [29] who reported that the spread ratio of cookies produced from refi ned fl our substituted with blends of pitaya peel fl our has a spread ratio of (5.90-6.00 mm). According to [30], cookie spread rate appears to be controlled by dough viscosity; dough with low viscosity causes cookies to spread at fast rate and vice versa. The fermented jackbean fl our could have contributed to the modifi cation of the wheat fl our. Bulk density of the shortbread biscuit were not signifi cantly (p>0.05) different (Table 6).

Sensory evaluation of shortbread biscuit samples
The sensory scores of the shortbread was presented in     of wheat fl our with fermented jackbean seed fl our did not impair sensory quality of biscuits. Therefore, jackbean fl our has potential use in biscuit production. The present obtained results are similar to that reported by [31], who noted that partially replacing wheat fl our with cassava fl our up to 15% did not alter the composite cookies acceptability.

Conclusion
The inclusion of fermented jackbean fl our to whet fl our greatly increased the proximate, mineral, physical and sensory property of the fl our and product. Jackbean fermentation increases nutrient bioavailability of the whole food materials.
Shortbread biscuits prepared from 20 % substitution of fermented jackbean fl our was comparably with the control samples in terms of the physical characteristics. Sensory scores also showed that sample B (90% wheat fl our and 10% fermented jackbean fl our)was preferred with reference to colour, fl avor, mouth-feel and overall acceptability. Consumption of shortbread biscuit fortifi ed with fermented jackbean fl our at 10 % and 20 % levels may therefore be encouraged, thus could be used as a nutritious food for children and adolescent in developing countries.