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In the first part of the experiment, we focused on the quality of Tofu. Our objective of this paper was mainly to investigate the yield of Tofu made from soybean and apricot kernels.

Tofu yield was calculated as weight of fresh Tofu per 100g total weight of detoxicated apricot (moisture 63.9%) and soybean kernels (moisture 7.8) at a ratio of 1:3. Tofu syrup was made by adding water amounting to 2.5 times the total weight of raw materials, and goes through same pressing pressure. Independent factors at four levels listed below were investigated one-by-one. Then, first order orthogonal design including A, B, C, and D factors with two middle levels in the table were conducted to investigate the main effects and any interactions.

Levels	A. CaSO4 added to syrup (w/v, %)	B. Coagulative temperature (°C)	C. Coagulating time (min)	D. Pressing temperature (°C)	E. Pressing time (min)
1	0.15	70	20	60	10
2	0.20	75	25	65	15
3	0.25	80	30	70	20
4	0.30	85	35	75	25

Individual experiments indicated that highest yield was achieved when adding CaSO₄ to syrup at 0.15%; maintaining temperature while coagulating at 80°C for 30min; and pressing coagulated Tofu base at 60°C for 10 min. Orthogonal contrast result indicated that factor A and B have highly significant interaction, and also, except D, there are significant differences with regard to A, B and C. Furthermore, highest yield (280g) could be achieved at three combinations of conditions, namely A1B1C2D2, A1B2C2D1 and A2B1C2D1.

The highest yield of Tofu achieved in this experiment fall in the yield range of conventional Tofu (13 representative soybean varieties at 229.3~551.0). Considering that detoxinated apricot kernels had much higher moisture content, the yield was acceptable.

This result implies that the novel Tofu product can produce acceptable yield.