Presented by Sarita Khedu (Miss) MPhil /PhD Faculty of Science Title of Project IMPROVING THE RHEOLOGICAL PROPERTIES & BAKING QUALITIES OF FLOUR (BLANK) BY THE USE OF REGULATORS AT LMLC Presented by Sarita Khedu (Miss) MPhil /PhD Faculty of Science 4/4/2019

OVERVIEW OF THE PRESENTATION Introduction Objectives of the study Review of literature Research Methodology Statistical Design Results & Discussion Conclusions & Recommendations 4/4/2019

Main ingredient - flour (Fox & Cameron, 1995 Belitz et al., 2004). INTRODUCTION I Wheat - primary material for bread making (BRI, 1989 ; Belitz et al., 2004), Main ingredient - flour (Fox & Cameron, 1995 Belitz et al., 2004). Bread and most other baked products can be made successfully from flours having a range of qualities. Bread widely enjoyed, important part of a healthy diet & enjoyed by all age groups in Mauritius 4/4/2019

Local milling industry : LMLC INTRODUCTION II Local milling industry : LMLC Addition of regulators to milled flour To abide by the contract signed to standardize the quality of flour To give an edge to the local and international baking industry Composition of regulators Oxidising agents (ascorbic acid) Reducing agents (L-Cysteine) Enzymes (amylases) (Lesaffre, 2001) 4/4/2019

1993 INTRODUCTION III WHO banned the use of potassium bromate Resulted in a great demand on food technologists for alternatives (Cavanaugh, 2002). local bakers cut down the required dose of improvers in the process of bread making since the non-bromate improvers are very expensive Quality problems + unhappy consumers Presently LMLC adds Regulator A 4/4/2019

Objectives of the Study To study the effect of the addition of a regulator (Reg A) on the rheological properties and baking qualities of blank flour To compare the effects of the addition of two new regulators (Reg B & Reg C) with the one in use at LMLC (Reg A) all at recommended doses To study the effect of Regulator B at lower dose (Reg B1) compared to the in use regulator at recommended dose (Reg A) 4/4/2019

strengthening of gluten by ascorbic acid LITERATURE REVIEW I Bread Research Institute of Australia (1989) : Action of α-amylase on starch strengthening of gluten by ascorbic acid Confirmed by Le Saffre (2001) an increase in dough extensibility by the addition of L-Cysteine Increase in bread volume by the use of ascorbic acid (Gujral, 2002) Lopper (1998) - malted wheat flour has a higher proportion of enzymes - mainly of  and -amylase It also contains protease, glucanase and other enzymes. 4/4/2019

LITERATURE REVIEW II Increase in dough extensibility flour capacity to hydrolyze starch by α-amylase & volume by the addition of L-Cysteine (Belitz et al., 2004) Jood et al. (2003) : α-amylases give softer bread crumb & hemicellulases make dough softer as well as promote gelatinization of starch malt flour - rich source of maltose, soluble proteins, amylolitic and proteolitic enzymes, and flavour substances - promote vigorous yeast activity, accelerate dough conditioning and contribute a distinctive flavour to the baked product - malted wheat flour have pronounced effects on Falling Numbers Hruskova et al. (2003) 4/4/2019

Regulator A : In use at LMLC Regulator B & C : New LITERATURE REVIEW III Regulator A : In use at LMLC Regulator B & C : New Composition of regulators Table 1 : Composition of Regulators used Regulator A Regulator B Regulator C Ascorbic Acid L-Cysteine Fungal Hemicellulase Wheat Flour Malted Wheat Flour α-amylase Enzymes Pure α-amylase 4/4/2019

Research Methodology Treatments Parameters assessed Table 2 : Treatments used 1 Blank 2 Reg. A (at 0.01%) 3 Reg. B1 (0.1%) 4 Reg. B (0.15%) 5 Reg. C (0.1%) Parameters assessed Rheological properties by Chopin Alveograph Chemical test : Falling Number Bake trials to assess Volume & Texture 4/4/2019

Statistical Design Randomised Block Design 5 Replicates SPSS 11.0 Software Two Way ANOVA without replication Tukey Honestly Significant Difference (HSD) used to determine the best treatment Dunnets Critical d to compare treatments with the control 4/4/2019

Figure 1 – Effect of the addition of regulators on bread volume RESULTS I Bread Volume Figure 1 – Effect of the addition of regulators on bread volume 4/4/2019

Table 3 – Effect of the addition of regulators on bread crumb texture RESULTS II Texture Table 3 – Effect of the addition of regulators on bread crumb texture Treatment Result Blk Firm Regulator A Soft & Elastic Regulator B1 Regulator C Regulator B2 Very soft & elastic Desirable for white pan bread 4/4/2019

Figure 2 – Effect of the addition of regulators on Falling Number RESULTS III Falling Number 4/4/2019 Figure 2 – Effect of the addition of regulators on Falling Number

Figure 4 – Effect of the addition of regulators on P / L ratio RESULTS IV P/ L Ratio Figure 4 – Effect of the addition of regulators on P / L ratio 4/4/2019

Table 4 – Summary of results Results V Table 4 – Summary of results Rheological Tests Chemical Bake Tests Tmt P L P/L FN Bread volume Texture BLK 106 mm 71mm within range (1.3-1.5) 491 1710 cm3 Firm Reg A ↑(-) ↓(-) above range outside optimum (469) ↑( +) desirable Reg B1 ↓↓( +) ↑↑( +) within range outside optimum (339)* Reg B ↓↓↓( +) ↑↑↑( +) below range Optimum (269) not desirable Reg C outside optimum (311)* 4/4/2019

DISCUSSION I Bread Volume Increase ascorbic acid , L-Cysteine & enzymes 4/4/2019

Plate 1 – Action of ascorbic acid on gluten DISCUSSION II Action of ascorbic acid on gluten 4/4/2019 Plate 1 – Action of ascorbic acid on gluten (Lesaffre,2001)

Plate 2 - Action of L-Cysteine on gluten strands DISCUSSION III Action of L-cysteine on gluten strands 4/4/2019 (Lesaffre,2001) Plate 2 - Action of L-Cysteine on gluten strands

Plate 3 – effect of hemicellulases on pentosans DISCUSSION IV 4/4/2019 Plate 3 – effect of hemicellulases on pentosans (Lesaffre,2001)

DISCUSSION V Bread crumb texture Reg A, B1 and C - soft and elastic (desirable) Reg B - not desired by consumers since slicing problems added enzymes which are responsible The proportion of enzymes a high level of α- amylase activity, indicated by a low falling number (usually < 200) will result in a sticky bread crumb. a low α- amylase activity, indicated by a high falling number (usually > 400) yields in a dry and firm texture (Operation Manual 8600). 4/4/2019

Table 4 - Interpretation of the different Falling Numbers 4/4/2019 DISCUSSION VI Falling Number Table 4 - Interpretation of the different Falling Numbers Falling Number Indication < 200 High α - amylase activity. Sprouted damaged wheat. Bread crumb firm and sticky 200-300 Optimum α - amylase activity. Bread crumb likely to be good Above 300 Low α -amylase activity. Bread crumb is likely to be dried. And a reduced bread volume is obtained. 4/4/2019

DISCUSSION VII Three regulators used contained added α-amylase High bread volume – Reg B & C malted wheat flour Lopper (1998)- malted wheat flour consists of α and β –amylases and many other enzymes. Hruskova et al. (2003) - amylases from malted wheat flour do have a pronounced effect on Falling Numbers 4/4/2019

Plate 3 – Action of enzymes on starch DISCUSSION VIII 4/4/2019 Plate 3 – Action of enzymes on starch (Lesaffre,2001)

DISCUSSION IX Overpressure ‘P’ gives an indication of the dough to resistance to deformation (Faridi & Rasper, 1987). The ‘L’ value is usually used to determine the dough extensibility (Faridi & Rasper, 1987). Ideal P/L values - 1.3-1.5. ineffectiveness of the in-use regulator (regulator A) in giving desired P/L value is noted, which is very well outside range 4/4/2019

Conclusions & Recomendations The in use regulator, regulator A did not give good rheological properties and baking qualities. Regulator C gave best results in all the parameters assessed followed by B1 RECOMENDATIONS To improve flour quality the mill can replace Regulator A by Regulator C. Very soft and elastic structure which is highly desirable for burgers and rounders – opt for Regulator B Option between regulator B1 OR C – Financial analysis 4/4/2019